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ACTA PHYTOGEOGRAPHICA SUECICA 82 EDIDIT SVENSKA VAXTGEOGRAFISKA SALLSKAPET

Risto Virtanen and Seppo Eurola

Middle oroarctic vegetation

in Finland and middle-northern

arctic vegetation on Svalbard

OPULUS PRESS AB

UPPSALA 1 997

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© R. Virtanen & S. Eurola 1 997

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DTP: Opulus Press AB Printed in Sweden, 1 997 by Fingraf, Sodertalje

Acta Phytogeogr. Suec. 82

Middle oroarctic vegetation in Finland and middle-northern arctic vegetation on Svalbard 3

Abstract. Risto Virtanen and Seppo Eurola. 1 997. Middle oroarctic vegetation in Finland and middle-northern arctic vegetation on Svalbard - Acta Phytogeogr. Suec. 82, Uppsala, 60 pp. ISBN 9 1 -72 1 0-082-6. (9 1 -72 1 0-482-5 . )

Plant communities of the middle oroarctic zone of northwestern Fennoscandia and middle-northern arctic areas of Svalbard were studied to describe the community types and their ecological relationships. The analyses were based on data sets collected both from subcontinental mountains of Finnish Lapland and from a geographically broad area of Spitsbergen, the main island of Svalbard. Plant communities were classified by a divisive clustering method (TWINSPAN) and the ecological relationships of the community clusters were examined by detrended correspondence analysis (DCA) . For northern Fennoscandia, edaphical ly differentiated series of community types from windexposed ridges to depression sites with snowbed vegetation were described. On siliceous substrates, the types in the series conformed to those described earlier. On calcareous soi l , the Dryas octopetala-Carex rupestris type occupied exposed ridges, the Cassiope tetragona-Dryas octopetala type sites with moderate snow cover, and the Salix polaris-Silene acaulis type moderate snowbed sites, while late snowbed sites harboured communities of the Saxifraga oppositifolia-Ranunculus sulphureus type. For Spitsbergen, the following three regionally distinguished series were described: ( 1 ) In the inner fjord region, wind-swept ridges were character

ized by the Saxifraga oppositifolia-Hypnum revolutum community. This community shows a gradual transition to communities rich in Dryas octopetala and mosses on sheltered slopes.

(2) At the southwestern-western coastal region, ridges were occupied by communities characterized by Racomitrium lanuginosum. These graded to moss and lichen-rich heaths, while depression sites harboured snow bed communities dominated by Sanionia.

(3) In the Dryas region, ridge heaths approached the vegetation of polar deserts. The sheltered sites were characterized by moss tundra communities and Sanionia snowbeds.

On the mountains of northern Fennoscandia, the plant communities seemed to be clearly differentiated in relation to the bedrock. On Spitsbergen, some edaphic differentiations exist among plant communities, but some of the differences obviously reflected climatic differences among the areas studied.

It was shown that the sheltered slopes and snowbed sites of Spitsbergen harbour copious moss vegetation dominated by robust (mainly pleurocarpic) mosses, whereas the corresponding habitats in northern Fennoscandia seem to consist of small bryophytes growing together with prostrate vascular plants and lichens. One reason for this may be the absence of herbivores (Norway lemming or brown lemming) feeding on mosses on Spitsbergen.

Nomenclature: Vascular plants (Lid & Lid 1 994), bryophytes (Soderstrom et al. 1 992) and lichens (Santesson 1 993 ; Andreev et al. 1 996).

Risto Virtanen and Seppo Eurola, Department of Biology, University of Oulu, P 0. Box 333, F/N-90571 Oulu, Finland.


Contents

1 Introduction

2 Material and Methods

2. 1 Sampling methods, sampled areas and their environmental characteristics

2.2 Climate

2.3 Grazer communities

2.4 Numerical analyses

3 Results: classification and ordination

3. 1 Northwestern Fennoscandia

3 . 1 . 1 Festuca ovina-Potentilla crantzii group

3 . 1 .2 Alectoria group

3. 1 .3 ]uncus trifidus-Cassiope tetragona group

3 . 1 .4 Salix herbacea group

3. 1 .5 Ranunculus glacialis group

3. 1 .6 Saxifraga oppositifolia group

3.2 Spitsbergen

3 .2. 1 Luzula confusa group

3 .2.2 Papaver dahlianum group

3 .2.3 Dryas octopetala group

3 .2.4 Alopecurus borealis-Aulacomnium turgidum group

3 .2.5 Sanionia snowbeds

3 .2.6 Wet moss snowbeds

4 Topographic patterns: series of communities in ridge-depression transects

4.1 Northwestern Fennoscandia

4.2 Spitsbergen

5 Vegetational differentiation in relation to edaphic factors

6 Abundance patterns of bryophytes in topographic and regional gradients

7 Acknowledgements

8 References

Appendices

5

6

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1 6

1 8

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47

1 Introduction

The Fennoscandian oroarctic (alpine) vegetation has been

subject of study in many classic works (Wahlenberg 1 8 1 2;

Nordhagen 1 928, 1 943; Kalliola 1 939; Gjrerevoll 1 956;

Dahl 1 957) providing a comprehensive reference to veg

etation types and their ecology . These studies mainly

concentrate on the vegetation of south-central Scandina

vian mountains and are restricted to the lower oroarctic

zone. From the middle oroarctic zone in the North, rather

tentative descriptions are available (Fries 1 9 1 3; N ordhagen

1 936, 1 955; Hedberg et al . 1 952). Most recent gradient

studies of oroarctic vegetation covering a broad geo

graphic area in northern Fennoscandia include main topo

graphic, altitudinal and regional patterns of oligotrophic

mountain heath vegetation with a large number of sam

ples (Haapasaari 1988; Oksanen & Virtanen 1995) . These

studies outline the vegetational relationships between

Fennoscandian mountain vegetation and the vegetation of

truly arctic areas. Gross climatically parallel areas for the

middle oroarctic zone (Ahti et al. 1 968) exist on Spitsbergen

where we also encounter gradients to northern arctic

tundra and polar desert zones (Elvebakk 1985) . The veg

etation of Spitsbergen has been treated in several works

since the twenties (e.g. Summerhayes & Elton 1 923,

1 928; Acock 1 940; Hadac 1 946; R(Zjnning 1 965; Eurola

1 968; Hofmann 1 968; Hartmann 1 980; see also Elvebakk

1 994). The approaches used in these studies reflect the

ideas of many phytosociological schools. Consequently,

the described vegetational noda are not always easily

comparable (Walker et al. 1 994), and it is sometimes

difficult to determine whether differences or similarities

in vegetation are real or whether they reflect methodo

logical differences between different authors. This has in

part hampered ecological comparisons between truly arc

tic vegetation and the vegetation on the mountains of

northern Fennoscandia. In the present paper, we have aimed to start by classifying plant communities based on

samples collected in a directly comparable way from

northern Fennoscandia and Spitsbergen, compare the de

scribed community types with those found in the earlier

literature, analyse the main gradients by indirect ordina

tion, and summarize the main vegetation patterns in the

form of mesoscale vegetation series. Thereafter, we dis

cuss the role of edaphic factors in differentiating commu

nities and patterns in bryophyte abundance.


2 Material and Methods

2.1 Sampling methods, sampled areas and their environmental characteristics

The material was collected during several occasions over a long period, and consequently the procedures used by us

were prone to variation in sample plot size and method of

placement of the sampling plot (Table 1 ) . One of the main

criteria was to sample the variation of vegetation along

presumed main ecological gradients (soil, topography) to

a large extent. Consequently, wind-exposed sites, late

snowbeds and various heath types were analyzed both on calcareous and more or less siliceous substrates. The

sampled sites were mostly underlain by glacial till . The

azonal vegetation on other soil-types, e.g. coastal pla

teaux with deltas, moraines or clay fields with sparse

vegetation were not sampled. A systematic sampling along

ridge-depression topographic transects was favoured when

ever possible. Species cover was estimated with the Hult

Sernander five-unit scale, with an added symbol '+' for

very low abundance, or by a direct estimation of percent

age cover. The cover was noted as an estimate of the area

of foliage projection for each species.

In northwestern Fennoscandia, the vegetation was sam

pled on subcontinental mountains of the northwestern

Enontekio community. One part of the material was sam

pled at Lake Kilpisjarvi (473 m above sea level, 69° 03' N,

20° 50' E) where mountains reach to altitudes of more

than 1 000 m above sea level. Many of the mountains are

characterized by overthrown Caledonian nappes with rela

tive altitudinal differences of more than 500 m (Fig. 1).

Fig. 1 . View over the mountains near Kilpisjarvi. Mt. Jehk:ats, alt. 950 m, with middle oroarctic heath vegetation. August 1 987. (Photo: Risto Virtanen.)



The other part of the data was sampled from mountains northeast of Kilpisjarvi, where the valley between the mountain Guonjarvam (69° 07' N, 21 o 10' E) and Duoljehuhput was one of the main sampling areas. The mountain slopes are mainly gentle, shaped by continental ice sheets, reaching altitudes of more than 900 m above sea level, while the mountain tops reach altitudes of about 1100 m. The terrains are mostly covered by soil cover, contrasting with the vast stone-block districts north of this area (the Gahpperus-GoddeniSsak area). The soil formations are often modified by cryoactivity that maintains polygonal stone rings (Ohlson 1964 ). The sites comprise both siliceous and calcareous soil substrates (Uusinoka 1980) which reflect the occurrence of bedrock both with calcium carbonate-rich caledonic dolomites and silicate-rich mountain schists.

On Spitsbergen, the study sites were more broadly distributed in three main areas. The first of the study areas was the inner fjord region of Isfjorden 08° 10' N, 15° 40' E), where most of the samples were obtained from the Adventdalen-Sassendalen area. The second area extended from the west-southwestern coastal area of Hornsund or 00' N, 15° 40' E) to the mouth oflsfjorden. The exact location of the sample sites of these two subareas is given by Eurola (1968). The third study area ranged from the Slettvika-NordenskiOlddalen area at the bottom of Van Mijenfjorden or 50' N, 16° 40' E) to Agardhdalen on the southeastern coast of Spitsbergen 08° 10' N, 18° 20' E) (Fig. 2).

In the inner fjord area, the Triassic, Jurassic and Cretaceous sediments prevail (Major & Nagy 1972). The mountains on both sides of Adventfjorden consist basically of Cretaceous sediments, overlain by lower Tertiary strata. At Sassenfjorden, the bottom part of the valley is built up of Permo-Carboniferous sediments (Winsnes et al. 1962). The coastal areas consist mostly of Hecla Hoek rocks composed of Proterozoic and older Paleozoic sediments and they were strongly faulted and metamorphozed during the Caledonian orogeny. The studied sites at Isbjornhamna are composed mostly of gametiferous mica schists

intercalated with marbles. The bottom of the Van Mijenfjorden area is composed of Tertiary deposits which are replaced by the Triassic, Jurassic and Cretaceous sediments in the Kjellstromdalen-Agardhdalen area. Considering Elvebakk's (1982) analyses, the Hecla Hoek bedrock-based substrates and those with mesozoic deposits give variable reactions from acidic to alkaline. The material from Spitsbergen was chiefly collected in areas where parent material of soils is circumneutral, and sampling sites with clearly siliceous and strongly alkaline parent material were not covered by us. This differed from the situation of northern Fennoscandia where parent material was more distinctly differentiated into siliceous and calcareous ones.

2.2 Climate

Climatological data from the studied mountain sites at northwestern Fennoscandia are scarce as there are no meteorological stations at higher altitudes. To provide some estimates for the climatic conditions in our study area in northwestern Fennoscandia, we calculated mean temperatures for locations at 880 m above sea level based on data from the weather station at Kilpisjarvi (Fig. 3). The records were available for the subalpine forest zone (altitude 480 m a.s.l., Jarvinen 1987). The transformation was performed according to recommendations of the N orwegian Meteorological Institute to use a cooling rate for periods December - February of 0.5 oC/100 m, March August 0.7°C, September - November 0.6°C. Some measurements were available for the alpine belt about 40 km west of the study sites (Mook & Vorren 1990). Mook & V orren ( 1990) gave data for the period June - October for altitudes 915 m and 1110 m measured 20 cm aboveground. The mean temperatures for the station at 915 m for the months June - October were as follows: 6.2, 6.4, 8.7, 2.7 and- 2.2°C, and for 1110 m 1.3, 1.8, 3.9,- 2.4 and - 4.8°C, respectively. These values indicated that temperatures decreased by ea. five degrees for every 200

Table 1 . Sample material from northern Fennoscandia and Spitsbergen. N = no. of samples.

Northwestern Fennoscandia Mts. at Kilpisjarvi Mt. Guonjarvam and Gahpperussak

Spit bergen SW-W coast (Hornsund) - Inner fjord area Kjellstrom-Agardhdalen area

* Data from Eurola ( 1968)

Plot size (m2)

0.25 4

25 25

N

126 81

58 56

Year of sampling

1986 1989-90

1964 *

1969


8 R. Virtanen & S. Eurola

Fig. 2. View over Mt. Friedrichfjellet, midway between Agardhdalen and Bellsunddalen. Moss-rich tundra and Bjarrnebreen. July 1 969. (Photo: Seppo Eurola. )

m increase in altitude. As the highest station was on the peak of the mountain, it might have been climatically pronouncedly extreme. Mook & Vorren (1990) also gave recorded minimum temperatures in June-August. At an altitude of 915 m, these were - 3.8,- 0.1 and - 1.5 oc, while values at 1110 m were - 6.3, - 4 .3 and - 6.5 oc, respectively.

The temperature data for Spitsbergen (Fig. 3) were obtained from the records of three meteorological stations encompassing the study areas (Steffensen 1982). Isfjord weather station was a coastal station, while Longyearbyen represented an inland station, and the data available from Hopen probably corresponded closest to conditions prevailing at the Agardhdalen region. We found published data from Hornsund for a one-year-period only 1957-1958 (Eurola 1968).

The temperature curves of northwestern Fennoscandia and Spitsbergen show that (1) winter temperature regimes are practically similar, but near-ground temperatures are probably lower in Spitsbergen due to thin snow cover (see below), (2) the calculated values for mean temperatures of the growing season in the lower part of the middle oroarctic zone of northern Fennoscandia are higher than those at


any area on Spitsbergen. In the upper altitudinal limit of the zone they are equal or even colder than in the most areas of Spitsbergen, as indicated by the data in Mook & Vorren (1990). The majority of samples of Fennoscandia are from altitudes over 900 m above sea level, and thus, the actual temperature regimes are more similar than indicated by the graphs, (3) differences between maximum and minimum temperatures are greater in Fennoscandia than on Spitsbergen, (4) the values of Hopen indicate a colder climate corresponding to northern arctic or upper oroarctic zones (Mook & Vorren 1990), and 5) night frosts in the summer are more infrequent at Spitsbergen than on the mountains of northern Fennoscandia. On Spitsbergen, some frosts of - 1.8°C were recorded only in July-August (Steffensen 1982).

Precipitation data were taken from the meteorological station reports (Steffensen 1982, Finnish Meteorological Institute) and should be considered as estimates for the actual rain fall (Fig. 3). The precipitation curves show more variation than the temperature does. In northwestern Fennoscandia ( Kilpisji:irvi area) the curve shows a relatively high amount of summer precipitation. In the inner fjord region of Spitsbergen the annual rainfall is the


1 0

5 c

0 i E � -5 ! 0 -1 0 E

� 0 E c

- 1 5

-20

70

60

50

40

2 30 E 20 E

1 0

0 c a

-,

a)

b)

a :; 0 � -, 0

• Kilplsjarvl 880 m

--+-- Longyearbyen

• lsfjord Radio

--o- Hopen

o. Hornsund

-••- Kllplsjarvl

--+-- Longyearbyen

• lsfjord Radio

--o- Hopen

----b- Hornsund

Fig. 3. Temperature (a) and precipitation (b) characteri tics of the study areas. Kilpisjarvi : the monthly mean temperatures for north we tern Fennoscandia. Calculated values for 880 m above sea level based on the data of the weather station at Kilpisjarvi ( 480 m above sea level) . The transformation as performed according to lapse rates for the periods December-February 0.5° C/ 1 00 m, MarchAugust O.r C, September-November 0.6° C. Other stations on Spitsbergen and Hopen according to Steffensen ( 1 982). The data for Homsund are from graphs in Eurola ( 1 968), based on measurements of 1 957- 1 958. The precipitation values ofHomsund are smoothed using running means of two successive month .

lowest: the annual mean precipitation in Longyearbyen is 208 mm. The coastal areas, western Isfjord and Hornsund receive about 400-450 mm. On Hopen, the annual mean is 400 mm. The inland station, Longyearbyen, shows the lowest values during the winter months. In the coastal area, the winter precipitation is relatively high. The low winter precipitation of the inner fjord region is in accordance with the typical situation in the circumpolar Arctic (Aleksandrova 1 988; Oksanen & Virtanen 1 995), while the relatively high values of the coastal areas indicate a higher degree of oceanity.

Little information is available on snow conditions

during winter. As a rule, the snow cover is thicker on mountains of northwestern Fennoscandia than on Spitsbergen. In the birch forest zone of the Kilpisjarvi area, the mean maximum snow depth is about 70 cm ( Hiltunen 1980). Above the treeline the distribution of snow is more variable and in depression sites the depth is usually 1 -2 metres or more. The soils in the snow bed sites are frozen during winter ( Hiltunen 1 980). The snow depth data from Svalbard are even more scanty than in northwestern Fennoscandia. According to the records available, the maximum averages are about 30 cm in the inner fjord region (Eurola 1 968). In depressions there can be



deep snow fields. The situation at Spitsbergen may correspond to that recorded at Barrow, northern coast of Alaska. According to Dingman et al. (1980), the temperature on the soil surface can be- 25°C in the coldest periods of the winter. The thin snow cover gives weak insulation, and thus the ground is exposed to extreme low temperatures. Permafrost is omnipresent on Spitsbergen and plays a significant role for site conditions (Eurola 1968; R�nning 1969; Stablein 1971).

2.3 Grazer communities

The middle oroarctic zone represents an ecosystem approaching the limits of closed vegetation cover that is relatively low productive with sparse annual biomass production. The plant production supports a trophic system with several grazers (Oksanen et al. 1996) of which reindeer and small mammals are the most important. In the district studied by us the reindeer population consisted of ea. 10 000 animals in the late 1980s which is about 1-4 individuals per km2 ( Kojola et al. 1993), but has decreased to ea. 6000 in the 1990s (1. Kojola, pers. comm.). Reindeer grazing is most intense in mid-summer. The key-stone small mammal of the study sites is the Norway lemming (Lemmus lemmus) showing drastic variation in densities. It may be virtually absent for periods up to 15 years, then copiously abundant during big outbreaks ( Kalela 1961). Mountain hare (Lepus

timidus), rock ptarmigan (Lagopus mutus) and arvicolids (Microtus agrestis, M. oeconomus and Clethrionomys

rufocanus) occur in the oroarctic zone ( Henttonen et al. 1977), but they fluctuate in density ( Laine & Henttonen 1983).

On Spitsbergen, the Svalbard reindeer (Rangifer

tarandus platyrhynchus) is the main grazer and totals 1 1 000 individuals (Norderhaug & Reimers 1976). The metapopulation is divided into several relatively discrete populations (Punsvik et al. 1980). In the inner Isfjorden region, the estimated density in areas close to the study plots has been 5.6 animals per km2 (Alendal & Byrkjedal 1976). A population has been observed in the ReindalenSveagruva-Agardhdalen area. On the west coast, reindeer has occurred sparsely. Another herbivore, the Svalbard ptarmigan (Lagopus mutus hyperboreus) occurs, but estimates of the population are unknown. In the Sveagruva area, an introduced muskox (Ovibos moschatus) population numbered 16 individuals in 1930 and some tens of individuals in the 1960s (pers. observ. by S.E.). This population has obviously become extinct in the late 1980s (Mehlum 1990). There are no lemmings on Spitsbergen, and small populations of Microtus epiroticus

(including M. arvalis) are only found near human settlements (Mehlum 1990).


2.4 Numerical analyses

Despite the materials containing sample plots of different sizes and the abundance values being estimated by different methods, we found it beneficial to jointly analyze the data sets in order to directly compare the vegetation units (Podani 1984: 80-83). For the numerical analyses, the cover classes were transformed to corresponding percentage classes (Oksanen 1976). Numerical analyses of the vegetation data were performed using these percentages. The TWINSPAN-clustering ( Hill 1979) was used to produce a classification for the plant communities. In the TWINSP AN run, the number of pseudospecies cut levels were set to three, with levels 0, 4, and 10. These levels produced a number of pseudospecies not exceeding the computation capacity of the TWINMAX - an enlarged programme version of TWINSPAN. On the other hand, these levels should not emphasize the influence of the dominant species, and the species occurring with low cover values should affect the classification. Thus the whole species composition, not only the dominant species, contributes to the classification. TWINSP AN divisions with eigenvalue > 0.2 were employed to produce a classification. The higher level clusters of TWINSP AN were used for arrangement of the community groups. To briefly convey an idea about the ecological characteristics of the groups, a physiognomic-site type name was also given. The subdivisions of these groups resulted in clusters that were regarded as community types or variants thereof. The community types were expected to have a characteristic species composition and to be ecologically interpretable. The variants shared much of the ecology of the main type, but the species composition and abundance relationships were likely to vary depending on local factors. We described the Fennoscandian community types as bound to the Finnish site-type system (e.g. Haapasaari 1988), while the vegetation units on Spitsbergen were called 'communities'.

Detrended correspondence analysis ( DCA) ordination (Hill & Gauch 1980) was used to reveal the major directions of variation (vegetation gradients) in the community data. Since TWINSP AN clearly divided the material into 'Spitsbergen' and 'Fennoscandia' as main groups of their own, separate ordinations were performed for northern Fennoscandia and Spitsbergen. The centroids (mean of the ordination scores for the first two DCA axes) of the TWINSPAN groups (community types) were calculated and standard deviation of the mean was calculated to indicate the dispersion of the plots. DCA scores were computed by the CANOCO 3.1 computer package (ter Braak 1988, 1990) using down-weighing of rare species and detrending by segments. Sample plots of wet and rocky habitats were omitted from the ordination, because they behaved as outliers.

3 Results: classification and ordination

In the first division of the TWINSPAN run (Fig. 4), the sample plots from northwestern Fennoscandia and Spitsbergen were practically exclusively separated from each other as only one plot from Fennoscandia was assigned to the cluster of Spitsbergen data. A more diffuse discrimination could have been expected due to the largely common species pool occupying climatically relatively similar areas, especially on geologically corresponding substrates. Nevertheless, this result indicates that communities in similar habitats are differentiated. This is partly due to differences in species composition between Fennoscandia and Spitsbergen. The differences in species composition are exemplified by the preferential species list given by TWINSP AN (Table 2). A corresponding result was also obtained in an analysis of data sets from Bear Island, Jan Mayen, Spitsbergen and the mainland ( Virtanen et al. 1997b). Due to this dichotomy, the communities of northwestern Fennoscandia and Spitsbergen are treated in separate sections.

0.502

FovPcrG AG JtCtG ShG RgG SoppG


The total material of northwestern Fennoscandia was firstly split by TW INSP AN into two large groups consisting of vegetations on wind-swept - weakly snowprotected and on sheltered slopes- snowbed sites (Fig. 4). The former group was further divided into three collective clusters, of which the first, the Festuca ovina

Potentilla crantzii group, represents eutrophic grassrich communities with indicators of calcareous soils. The vegetation within this cluster does not clearly correspond to any higher level vegetation unit described earlier, but it seems to be intermediate between the traditional unit Caricetalia curvulae (Braun-Blanquet 1926; Dahl 1957, or Juncion trifidi Nordhagen 1943) and Sesle rietalia coeruleae ( Braun- Blanquet 1926, or Kobresieto-Dryadion Nordhagen 1943). The remaining material in this branch of the dendrogram was divided into two clusters, of which the first cluster contained

LeG PdG DocG AoiAtG SaS WMS

Fig. 4. Dendrogram representing the major divisions of a TWINSP AN classification of the 303 sample plots . The eigenvalues of the divisions are indicated. The community groups of northern Fennoscandia: FovPcrG - Festuca ovina-Potentilla crantzii group, AG Alectoria group, JtCtG - ]uncus trifidus-Cassiope tetragona group, ShG - Salix herbacea group, RgG - Ranunculus glacialis group, SoppG - Saxifraga oppositifolia group. The community groups of Spitsbergen : LeG - Luzula confusa group, PdG - Papaver dahlianum group, DocG - Dryas octopetala group, AbAtG - Alopecurus borealis-Aulacomnium turgidum group, SaS - Sanionia snowbed communities, WMS - Wet moss snowbeds.



vegetation on snow-protected sites, to be called the Alectoria group. This corresponds to the traditional higher level vegetation unit Loiseleurieto-A rctostaphylion

( Kalliola 1939, Nordhagen 1943) and to the Arcto

staphylos and Cassiope tetragona- Vaccinium groups of Oksanen & Virtanen (1995). The second cluster included vegetation of snow-protected sites and corresponded to the traditional Juncion trifidi Scandinavicum

(Nordhagen 1943) and the ]uncus trifidus-Cassiope

tetragona group of Oksanen & Virtanen ( 1995). The main cluster with chionophilous-snowbed vegetation was divided into three clusters, of which one is called the Saxifraga oppositifolia group. It is a relatively heterogeneous group, not similar to any higher level vegetation unit described earlier, but it largely comprises a broad group of snow bed communities rich in calciphiles (Gjrerevo11 1956). The snow bed vegetation of siliceous substrates was subsequently divided into two main groups, called Salix herbacea and Ranunculus glacialis groups, recognized also by Oksanen & Virtanen (1995). These differ ecologically from each other in duration of snow cover. In total, the northern Fennoscandian material comprises six community groups including 30 community types or variants.

The ecological relationships of the community types were analysed by means of DCA ordination (Fig. Sa). The first DCA axis seems to be related to snow cover, as the snowbed communities (typical species: Anthelia

juratzkana, Kiaeria starkei, and Polytrichastrum sex

angulare; Fig. 5b) were placed in the left and the ridge heaths were scored in the upper right of the figure (typical species: Alectoria nigricans, Empetrum nigrum ssp. hermaphroditum and Flavocetraria nivalis) . The second

3

Fig. 5a.

2 3

DCA 1 (0.651)

4 5

axis seems to reflect mainly edaphic differentiation along gradient from heaths of siliceous substrate (typical species: Gymnomitrion corallioides) to communities with indicators of calcium carbonate (e.g. Car ex rupestris

and Dryas octopetala) but also to communities on relatively nutrient-rich sites (Anthoxanthum odoratum ssp. alpinum, Poa alpina and Viola biflora) .

Table 2. Preferential (NW Fennoscandia/Spitsbergen) and non-preferential vascular plants given by the first TWINSPAN division. Species with * are encountered exclusively either in the Fennoscandian or the Spitsbergen material.

NW Fennoscandia

Carex bigelowii*

Cassiope hypnoides*

Cassiope tetragona

Festuca ovina*

]uncus trifidus*

Salix herbacea*

Sibbaldia procumbens*

Silene acaulis

Vaccinium vitis-idaea*


Non-preferential

Bistorta vivipara

Dryas octopetala

Spitsbergen

Alopecurus borealis*

Cerastium arcticum

Draba alpina*

Draba subcapitata*

Luzula arctica*

Luzula arcuata ssp. confusa

Oxyria digyna

Papaver dahlianum*

Pedicularis hirsuta

Poa alpigena*

Poa arctica

Salix polaris

Saxifraga cernua

Saxifraga cespitosa

Saxifraga nivalis

Saxifraga oppositifolia

Stellaria longipes*

-2.0


b

.eru lie

Erne her

. Gym cor

Bet.nan

• Callap .

Ale nig•

Tha ver•

Die fus•

Cas tet. Och fri. Die elo•

Cla coc • •Cia g ra

• •Poljun

.Cet niv

•• cetcuc Bry div

Gy"!con Cas

.hyp

Cet del• Lophozi•

.ste atp

.Die sco

Cetcri

Cla :.m •

.Pol pit ·

vac vit .

Pti cil

Ple.alb .Luz con •Anamin

Con tet• .Cep sp

•sat her Ki� sta •Car big

•Sib pro

Cet ist• Bar flo

• And rup

Tri qui .

san.unc

•Jun tri

•Sal pol •Sit aca

Pol viv•

•Pol alp

•Antodo

•Poaalp

•Hyl ala

. . Fes ovi

. Viobif

•Dry oct

+6.0

Fig. 5 . Ordination diagram of axis 1 against axis 2 using Detrended Correspondence Analysis (DCA) for the TWINSPAN groups (a,

overleaf) in the Fennoscandian material. The centroids (point) are mean sample scores for the ftrst two DCA axes. Circled area indicates S.D. of the scores with respect to the axes. APsT - Antheliajuratzkana-Polytrichastrum sexangulare type, CbT - Carex bigelowii type, CbSpT - Carex bigelowii-Salix polaris type, ChJtTe/ChJtTf - Cassiope hypnoides-Juncus trifidus type, DocCrT - Dryas octopetalaCarex rupestris type, DocCtT - Dryas octopetala-Cassiope tetragona type, ECtTa/ECtTc - Empetrum-Cassiope tetragona type, ECtATb/ECtATc - Empetrum-Cassiope tetragona-Alectoria type, EFnT - Empetrum-Flavocetraria nivalis type, GymnT - Gymnomitrion type, FovDocC - Festuca ovina-Dryas octopetala community, FovDocHC - Festuca ovina-Dryas octopetala-Hylocomium community, FovPcrT - Festuca ovina-Potentilla crantzii type, FovSalpSaC - Festuca ovina-Saussurea alpina-Sanionia community, JtCtTCb -]uncus trifidus-Cassiope tetragona type, Carex bigelowii variant, JtCtTCd - ]uncus trifidus-Cassiope tetragona type, Cetrariella delisei variant, JtCtTe/JtCtTf - ]uncus trifidus-Cassiope tetragona type, typical variants, JtCtTg - ]uncus trifidus-Cassiope tetragona type, graminoid variant, JtCtTm - ]uncus trifidus-Cassiope tetragona type, mossy variant, JtCtTPh - ]uncus trifidus-Cassiope tetragona type, Polytrichum hyperboreum variant, KPC - Koenigia islandica-Phippsia algida community, ShChT - Salix herbacea-Cassiope hypnoides type, ShKiT - Salix herbacea-Kiaeria type, ShKiTCb - Salix herbacea-Kiaeria type, Carex bigelowii variant, SpSacT - Salix polarisSilene acaulis type, SoppRsT - Saxifraga oppositifolia-Ranunculus sulphureus type, TsSaT - Trisetum spicatum-Sanionia type. DCA ordination of the most common species (b) Ale nig - Alectoria nigricans, Ana rnin - Anastrophyllum minutum, And rup - Andreaea rupestris, Ant jur - Anthelia juratzkana, Ant odo - Anthoxanthum odoratum ssp. alpinum, Bar flo - Barbilophozia floerkei, Bet nan -Betula nana, Bry div - Bryocaulon divergens, Cal lap - Calamagrostis lapponica, Car big - Carex bigelowii, Car rup - Carex rupestris, Cas hyp - Cassiope hypnoides, Cep sp - Cephalozia spp. , Cet cri - Cetraria islandica ssp. crispiformis, Cet cue - Flavocetraria cucullata, Cet del - Cetrariella delisei, Cet isl - Cetraria islandica, Cet niv - Flavocetraria nivalis, Cla arb - Cladina arbuscula, Cla gra - Cladonia gracilis, Con tet - Conostomum tetragonum, Die elo - Dicranum elongatum, Die fus - Dicranum fuscescens, Die sco - Dicranum scoparium, Dry oct - Dryas octopetala, Emp her - Empetrum nigrum ssp. hermaphroditum, Fes ovi - Festuca ovina, Gym con -Gymnomitrion concinnatum, Hyl ala - Hylocomium splendens var. alaskanum, Jun tri- ]uncus trifidus, Kia sta - Kiaeria starkei, Lophozi - Lophozia spp. , Luz con - Luzula arcuata ssp. confusa, Phy cae - Phyllodoce caerulea, Ple alb - Pleurocladula albescens, Poa alp - Poa alpina, Pol alp - Polytrichastrum alpinum, Pol jun - Polytrichum juniperinum, Pol pil - Polytrichum pi life rum, Pol sex - Polytrichastrum sexangulare, Pol viv - Bistorta vivipara, Pti cil - Ptilidium ciliare, Sal her - Salix herbacea, Sal pol - Salix polaris, San unc - Sanionia uncinata, Sib pro - Sibbaldia procumbens, Sil aca - Si le ne acaulis, Ste alp - Stereocaulon alpinum, Tha ver - Thamnolia vermicularis, Tri qui - Tritomaria quinquedentata, Vac vit - Vaccinium vitis-idaea, Vio bif - Viola biflora.



FovDocC FovDoHC FovPcrT FovSalpSaC JtCtTm

Fig. 6. TWINSPAN division of the Festuca ovina-Potentilla crantzii group. FovDocC - Festuca ovina-Dryas octopetala community, FovDocHC - Festuca ovina-Dryas octopetalaHylocomium community, FovPcrT - Festuca ovina-Potentilla crantzii type, FovSalpSaC - Festuca ovina-Saussurea alpinaSanionia community, JtCtTm - June us trifidus-Cassiope tetragona type, mossy variant.

3.1.1 Festuca ovina-Potentilla crantzii group

Chionophobous-chionophilous steppe-like heath vegeta

tion on moderately calcium carbonate-rich substrate;

Appendix 1, Fig. 6

This community group consists of vegetation characterized by Festuca ovina together with a variable eo-occurrence of indicators of (at least weakly) carbonate-rich substrate (e.g. Dryas octopetala, Potentilla crantzii, Salix

reticulata, Saxifraga spp. and Viola biflora) and grasses such as Anthoxanthum odoratum ssp. alpinum and Poa

alpina. Physiognomically, the vegetation looks like grassy meadows, or maybe better, cold steppes consisting of a large number of vascular plants (more than 50 altogether). This vegetation may represent an ecological counterpart to cold steppes typical of continental mountain regions. These communities develop into arctic dwarf shrub heaths, and in this respect such relations as conveyed by Lloyd et al. (1994) in Alaska might play a certain role also in subcontinental northern Fennoscandia (see also Nordhagen 1943:183).

This group shows affinities with the traditional association F estucetum ovinae alpicolum thoroughly described by N ordhagen (1943) from Sikilsdalen, southern Norway. The cover of lichens, in some communities those of bryophytes, are many times greater in Nordhagen's (1943) material than in ours. On the other hand, lichen cover in


Nordhagen's types, sustained by cattle grazing (the 'Festuca ovina-Potentilla crantzii sosiasjon'), are more comparable to those in our material in which the relatively heavy reindeer trampling has probably reduced the abundance of lichens. In part, this vegetation shows affinities to the Kobresieto-Dryadion (Nordhagen 1943, 1955) due to a relatively rich occurrence of calciphilous species. However, the species composition of the typical Kobresieto-Dryadion communities is somewhat different. This may reflect a situation where the Festucetum

ovinae alpicolum and the Kobresieto-Dryadion communities coexist on mountain slopes where soil properties are heterogeneous which also contributes to large vegetational heterogeneity (Nordhagen 1943: 579-580). In a broader geographical context, Nordhagen (1943) considers the association Festucetum ovinae alpicolum (as part of the Juncetum trifidi) analogous with the Caricetum

curvulae Braun-Blanquet in the Alps, but their ecological or phytosociological relationships have not yet been fully understood ( DierBen 1992).

In the DCA ordination, this group formed a relatively well separated cluster (Fig. Sa). The communities seem to be differentiated in respect to duration of snow cover and nutrient status. Consequently, the first four community clusters can be arranged in the following order with increasing snow cover: FovDocC, FovDocHC, FovPcrT, and FovSalpSaC. Apart from these, cluster JtCtTm seems to be close to the oligotrophic ]uncus trifidus-Cassiope

tetragona heaths placed in the central part of the ordination space. This community might be equally well included in the ]uncus trifidus-Cassiope tetragona group (described below).

In our material, vegetation of the Festuca ovina

Potentilla crantzii group occurs only on the eastern slopes of Mt. Saana, just below the grand vertical mountain walls at an altitude of about 900 m above sea level. Such landscape qualities obviously generate special ecological conditions. The slope is steep and chiefly south-facing, thus it receives much solar radiation. Therefore, soils are relatively dry and warm as compared to the middle oroarctic zone in general. Warmth can last overnight due to stored heat in the soil (oven effect), and warm air masses are uplifted by inversion. Soil substrates are only weakly acidic due to calcareous bedrock and steep topography. Moreover, reindeer grazing may enhance nutrient turnover, as it delays the development of dense dwarf shrub vegetation and promotes the growth of graminoids ( Kalliola 1939: 172-173; Dah1 1957: 106).

Within this community group, five clusters were produced by TWINSPAN. The composition of these clusters did not suggest that they would represent any distinct type of vegetation, rather they might be best regarded as fixed points in a vegetational continuum. Moreover, as the data of this vegetation came from one locality (slope of Mt. Saana), we refrained from describing them all as new


community types and mainly discuss their species composition and ecological characteristics.

Festuca ovina-Dryas octopetala community (FovDocC)

This community is characterized by the occurrence of indicators of calcium carbonate mixed with patchily growing Festuca ovina and Dryas octopetala. Calciphilous plants are found both among cryptogams (e.g. Cladonia

pocillum and Lescuraea saxicola) and vascular plants (e.g. Carex rupestris and Draba daurica). Most of the species have a low frequency, but as a whole , the species number of the community is high. The species richness of the community may be partly attributable to the presence of many small mosses (e.g. Bryum argenteum and Tortula

norvegica) which occupy mineral soil gaps created by small-scale disturbances. Probably, the open gaps also favour coexistence of many saxifrages.

This community resembles the ' Carex rupestris

Encalypta rhaptocarpa-sosiasjon' typical of calcareous rock ledges in Sikilsdalen, Norway (Nordhagen 1943). The Dryas octopetala-Carex rupestris type, described below, is ecologically related to this community but represents vegetation on more extremely wind-swept sites. The material in this community stems partly from similar exposed rock ledges at the basis of the vertical rock walls of Mt. Saana.

Festuca ovina-Potentilla crantzii type (FovPcrT)

This community has a fairly dense cover of Festuca ovina

giving a meadow-like appearance. The indicators of calcium carbonate are fewer than in the community FovDocC described above, but e.g. Cerastium alpinum, Dryas

octopetala, and Silene acaulis are frequently present. This community is prevalent on sheltered slopes. It resembles the 'Festuca ovina-Potentilla crantzii -sosiasjon' (Nordhagen 1943) which is regarded by Nordhagen (1943) as a secondarily arisen Festuca ovina heath, i.e. a dwarf shrub heath changed to a Festuca ovina dominated community by the grazing of horses. This corresponds to the Potentillo

Festucetum ovinae (Dahl 1957) which is sustained by grazing, while without any grazing, a shrub heath or a shrub heath with herbs would prevail.

For practical purposes (e.g. for needs of vegetation mapping) this vegetation is provisionally described as a new type to be called the Festuca ovina-Potentilla crantzii

type (FovPcrT) with the ecological characteristics of this community group.

Festuca ovina-Dryas octopetala-Hylocomium alaskanum

community (FovDocHC)

This community has a bottom layer with a relatively high total moss cover including Dicranum spp. and Hylocomium

splendens var. alaskanum. The field layer consists of a mixture of plants typical of various habitats. There are species of snow-protected sites (Phyllodoce caerulea,

Salix polaris and Viola biflora) and species typical of mesic sites (Bistorta vivipara and Carex vaginata) and species typical of dry ridges ( Vaccinium vitis-idaea). This community probably represents a transition between dwarf shrub heaths and the meadow-like heath patches characterized by Festuca ovina. Like the community above, this community resembles the 'Festuca ovina-Potentilla

crantzii -sosiasjon' (Nordhagen 1943: 200-201) and the Potentilleto-Festucetum ovinae of Dahl (1957: 106-109) . In Nordhagen's ( 1943) sample data, there is a Hylocomium

variant with a large cover of Hylocomium splendens. In our material, the cover of Hylocomium is not large, but some ecological similarity may exist between these two communities. This somewhat mixed vegetation supports the assertion above that the F estuca ovina heaths show transitions to dwarf shrub heaths without any distinct borders. Natural grazing may be one of the structuring mechanisms within these gradients (Oksanen 1990).

F estuca ovina-Saussurea alpina-Sanionia uncinata com

munity (FovSalpSaC)

This community represents the most chionophilous vegetation in this community group. The characteristic species are Sanionia uncinata and Saussurea alpina. Dwarf shrubs are missing or are very scarce. Otherwise, the field layer is relatively heterogeneous in its composition : some plots have a large cover of Viola biflora while some other plots contain Cerastium alpinum, due to variation in snowduration. V. biflora-characterized communities emerge later from snow than the ones characterized by C. alpinum.

Like the FovPcrT and FovDoc HC described above, this community resembles the 'Festuca ovina-Potentilla

crantzii sos iasjon' of Nordhagen (1943). Especially, the sample plots representing the Polytrichum juniperinum

Cetraria islandica variant (Nordhagen 1943: 200-201) seem to have a relatively similar species composition. Also some of the samples of 'arktische Festuca ovina

Wiesen' in Kalela (1939) from Kalastajansaarento at the N E coast of Fennoscandia are floristically relatively similar, suggesting an affinity to vegetation found normally in the lower oroarctic zone. In our material, the closest community type is the Trisetum spicatum-Sanionia type (see below) that occupies sites with more late-lying snow.

]uncus trifidus-Cassiope tetragona type, mossy variant

(JtCtTm)

This community is characterized by patchily occurring Cassiope tetragona and F estuca ovina. The bottom layer is rich in mosses (Dicranum scoparium and Hylocomium

splendens var. alaskanum). In the ordination, this community cluster is placed relatively close to a community belonging to the ]uncus trifidus-Cassiope tetragona group [the ]uncus trifidus-Cassiope tetragona type, graminoid variant JtCtTg (Fig. Sa)]. This variant has Polytrichum

species as most the prominent in the bottom layer, few


1 6 R. Virtanen & S. Eurola

Dicranum spp. and/or Hylocomium. These two variants can hardly be regarded as s imilar. The 'm' variant community differs from the community types in the ]uncus tri.fidus

Cassiope tetragona group (see below) by the occurrence of e.g. Saxifraga nivalis or more rarely S. cespitosa and S.

oppositifolia, indicating calcareous soil substratum. These communities most l ikely represent an intermediate vegetation between the Festuca ovina-Potentilla crantzii and the ]uncus trifidus-Cassiope tetragona heaths.

3.1.2 Alectoria group

Chionophobous vegetation rich in dwarf-shrubs. Appen

dix 2, Fig. 7

This community group includes vegetation with an abundant occurrence of chionophobous species: Alectoria

nigricans and A. ochroleuca occur constantly, along w ith other l ichens typical of wind-swept sites (e.g. Bryocaulon

divergens, Cetraria nigricans, Flavocetraria nivalis,

Sphaerophorus globosus, and Thamnolia vermicularis)

(Fig. 5b ). Otherwise, the species composition differs quite drast ically among the community clusters. One of the communities is characterized by calciphilous species, while in the other communities, species typical of siliceous substrates are prevalent. The former community resembles the associations included in the Kobresieto-Dryadion

(Nordhagen 1 943) and the latter shows affinit ies to the Loiseleurieto-Arctostaphylion ( Kalliola 1 939) and to the Loiseleurio- Vaccinietea (Daniels 1 994 ). These commu-

DocCrT ECtATb ECtATc GymnT

Fig. 7. TWINSP AN divisions of the Alectoria group. DocCrT -Dryas octopetala-Carex rupestris type, ECtA Tb/ECtAc -Empetrum- Cassiope tetragona-Alectoria type, GymnT -Gymnomitrion type.


nities differ, however, from the Loiseleurieto-Arctosta

phylion by the total absence of Arctostaphylos alpina and Loiseleuria procumbens. This is probably due to the fact that our plots lie above the al t itudinal l imit for common occurrence of these species (wide-spread in the lower oroarctic zone). The four types of this group can be described as follows:

Dryas octopetala-Carex rupestris type (DocCrT)

A dist inct community identified by TWINSP AN consists of s ix plots with calciphilous plants and a bottom layer w ith indicators of chionophobous condit ions. Dryas

octopetala dominates and another xeric calcicole species, Car ex rupestris, is common. The vegetation of this type is patchy due to frost heaving, wind abrasion and accumulat ion of weathered mater ial. Also rare species, such as Arnica angustifolia ssp. alpina, Carex glacialis and among mosses e.g. Campylophyllum halleri, Hypnum bambergeri

and Schistidium tenerum were observed. These habitats at Kilpisjarvi are typically found on the steep slopes of Mt. Saana and on wind-exposed s ites on the dolomite peak of Mt. Guonjarvam. This type appears to be restr icted to a few topographically rugged localities which are less accessible for reindeer. On these s ites, Dryas octopetala

often forms a nearly closed cover. This community corresponds to some sample plots in

Nordhagen's ( 1 936) 'artenarme Dryas-Carex rupestris

Soziation', and his (1955) Dryadetum octopetalae rich in Carex rupestris, Bringer's ( 1 96 1 ) Epibryo-Dryadetum

(Dryas-Carex rupestris-fazies). It can also be regarded as the middle oroarctic counterpart of Kalliola's ( 1 939)

'Dryas-Alectoria-Flavocetraria nivalis-Soziat ion', and Kalela's ( 1 939) ' Carex rupestris-Wiese ' . On Spitsbergen, the corresponding noda are the Rupestri-Dryadetum

( R�nning 1 965) and the Carici rupestris-Dryadetum

( Hartmann 1 980), with as characteristic species Draba

subcapitata and Schistidium apocarpum. Our data from Spitsbergen do not contain sample plots which clearly represent this type of vegetation .

Empetrum-Cassiope tetragona-Alectoria type (ECtA Tb,

ECtATc)

These two community clusters, ECtATb and ECtA Tc, show aff init ies to the Cassiope tetragona-Cetraria

n ivalis type (CtCnT), the Vaccinium-Alectoria type (V AT) and the Empetrum-Phyllodoce-Alectoria (EPAT) of Oksanen & V irtanen ( 1 995) . One of them ( ECtATb) can be regarded as an intermediate type between the Cassiope tetragona-Flavocetraria n ivalis type and the Vaccinium-Alectoria type, while the other ( ECtATc) resembles the Empetrum-Phyllodoce-Alectoria type, except for the scanty occurrence of Phyllodoce caerulea.

The three community types, CtCnT, EPAT and VAT, form a relatively d iffuse pattern of variat ion where local condit ions and stochastic processes influence the


abundance rela tionships between er icaceous plants. Vaccinium vitis-idaea seems to thrive best in contact w ith pure rock, probably because its strong vegetative reproduction makes it sensitive to cryoperturbation. Empetrum nigrum ssp. hermaphroditum reproduces also vegetat ively (Soyr inki 1939) which makes it sensitive to uprooting in s ites w ith intense cryoperturbation. Phyllodoce caerulea has only weak adventitious roots, and it is thus res is tant to cryoperturba tion (Soyr ink i 1939 ; Dahl 1957) . The same appears to apply to C.

tetragona (Warming 1908) which, moreover, is better adapte d to the m iddle arct ic and m iddle oroarctic conditions , and thus tends to replace P. caerulea, if present in the spec ies pool. It seems thus reasonable to regar d the Cassiope tetragona-Cetraria nivalis type and the Empetrum-Phyllodoce-Alectoria type as local var iants of a s ingle type; the latter variant being ma inly encountered outs ide the range of C. tetragona. The Vaccinium

Alectoria type, in turn, occurs locally and changes gradually into the other types so that it is impractical to dis tinguish it as a type of its own. We thus propose that these three vegetation noda, along w ith the clusters ECtA Tb and ECtA Tc in our material, w ill be regarded as var iants of a more inclusive community type , to be referred to as the Empetrum-Cassiope tetragona

Alectoria type ( ECtAT). Closest counterparts are de-

0.235

scr ibed from Greenland ( Cassiopetetum tetragonae;

Bocher 1933; Daniels 1982).

Gymnomitrion type (GymnT)

This community is characterized by chionophobous species that are common in the community group. However, now Gymnomitrion corallioides occupies relatively large areas in the w ind-exposed centres of elevated polygons, while the hollows are rich in Dicranum and Polytrichum

moss species. The hollows are also occupied by vascular plants demanding protection from strong abrasive w inds (e.g. Betula nana, Cassiope tetragona, Empetrum nigrum

ssp . hermaphroditum and Vaccinium vitis-idaea) . This community prevails on mountain top plateaux where soil conditions are suitable for the development of polygons. In these habitats, slow-rate cryoperturbation, relatively oceanic climate ( Haapasaari 1988) and/or reindeer trampling (Nordhagen 1943) seem to maintain frost boils colonizable for hepatics . These frost boils seem to favour especially G. corallioides. When the polygons are more intensely frost-heaved, the plant cover becomes extremely sparse. On the other hand, when they are stable, then w in d-har dy l ichens, such as A lectoria nigricans,

A. ochroleuca, and Flavocetraria nivalis, occur with a high cover ( if not decimated by reindeer). This type seems to represent a parallel type for the ECtA T that prevails on

ECtTa EFnT ECtTc JtCtTCb JtCtTe JtCtTf JtCtTg JtCtTPh

Fig. 8 . TWINSPAN divisions of the ]uncus trifidus-Cassiope tetragona group. ECtTa/ECtTc - Empetrum-Cassiope tetragona type, EFnT - Empetrum-Flavocetraria nivalis type, JtCtTCb - ]uncus trifidus-Cassiope tetragona type, Carex bigelowii variant, JtCtTe/JtCtTf - ]uncus trifidus-Cassiope tetragona type, typical variant, JtCtTg - ]uncus trifidus-Cassiope tetragona type, graminoid variant, JtCtTPh - ]uncus trifidus-Cassiope tetragona type, Polytrichum hyperboreum variant.



more stable ridge s ites. The frequent and relatively intense cryoactivity counteracts leaching and enables the occurrence of calciphilous plants, e.g. Dryas octopetala,

in the centres of polygons (see also Jonasson & SkOld 1983) .

3.1.3 ]uncus trifidus-Cassiope tetragona group

Chionophilous vegetation rich in graminoids and/or dwarf

shrubs; Appendix 3, Fig. 8

The core of the materia l in this community group cons ists of TWINSP AN clusters with vegetat ion corresponding to the tradit ional alliance Juncion trifidi scandi

navicum (Nordhagen 1943) and the ]uncus trifidus

Cassiope tetragona group in Oksanen & Virtanen ( 199S) . In the ordination space, most of the types assigned to th is group take an interme diate pos it ion between the ch ionophobous heath types (the Alectoria group) and Festuca ovina-Potentilla crantzii heaths (the Festuca

ovina-Potentilla crantzii group), while clusters EFnT and ECtTc overlap with the chionophobous heaths (Fig. Sa) . These two latter community clusters are r ich in dwarf shrubs, and they also have a species composition characterized by chionophobous species and thus resemb le the vegetation types in the Cassiope tetragona

Vaccinium group of Oksanen & Virtanen (199S). However, the group mainly represents sl ightly-moderately ch ionophilous middle oroarctic heath vegetation in accordance with the ]uncus trifidus-Cassiope tetragona

group in Oksanen & Virtanen (199S) .

Empetrum-Cassiope tetragona type (ECtTa, ECtTc)

The pair of clusters (ECtTa and ECtTc) are characterized by Cassiope tetragona occurring with a relatively high cover. The other of them (ECtTc) has Empetrum nigrum

ssp . hermaphroditum as eo-dominant, while among l ichens ch ionophobous Sphaerophorus globosus and Thamnolia vermicularis are typical . Among mosses Aulacomnium turgidum, Hylocomium splendens var. alaskanum, and Racomitrium lanuginosum are relatively constant and g ive some oceanic character . This community is chiefly encountered on westerly slopes of the mountains at Kilpisjarvi exposed to marit ime north Atlant ic winds (Fig. 9). The cryptogam layer of the other cluster (ECtTa) is r ich in l ichens, but also Hylocomium splendens

var . alaskanum is relatively abundant. Festuca ovina occurs scattered and ]uncus trifidus is totally absent. The c lusters ECtTa and ECtTc are not very close to each other in the ordination (Fig. Sa), which suggests an ecological differentiation: ECtTc takes a quite extreme position near the types of the Alectoria group. However, the community is not confmed to the most wind-exposed s ites, but rather occupies concave slopes retaining a continuous


snow cover at winter t ime . In the ordination ECtTa is placed among the luncus trifidus-Cassiope tetragona type suggesting that the dwarf shrub heaths and the vegetation of the gram ino id-rich vegetation of Juncion trifidi

scandinavicum are intermingled. The community clusters ECtTa and ECtTc do not

clearly correspond to any of the types of Oksanen & Virtanen (199S). The Cassiope tetragona-Dicranum

fuscescens association of Nordhagen (19SS) is s imilar, except in our material Diapensia lapponica is m issing, Dicranum fuscescens and Flavocetraria nivalis occur in lower and Salix herbacea in h igher abundance than in Nordhagen ' s material. The closest community types are the continental ]uncus trifidus-Cassiope tetragona type and the oceanic Salix herbacea-Empetrum type, that have less Cassiope tetragona. The occurrence of such mosses as Racomitrium lanuginosum creates affinities to the oceanic Empetrum heaths which in the middle oroarctic zone of oceanic sectors develop into a vegetation of the Salix

herbacea-Empetrum type (Oksanen & Virtanen 199S). On these grounds we suggest that these community c lusters collectively represent a new transitional subcontinental-suboceanic type, to be called the Empetrum-Cassiope

tetragona type (ECtT). Relatively s imilar counterparts are reported from West Greenland (Bocher 19S4, 1963; Daniels 1982 : heaths r ich in Cassiope tetragona).

Empetrum-Flavocetraria nivalis type (EFnT)

This community c luster represents chionophobous heath vegetation, as indicated by the occurrence of Alectoria

spec ies together with Flavocetraria nivalis. Betula nana

is creeping over ground and occurs with a relatively high cover. Th is community corresponds rather well to the Empetrum-Cetraria nivalis type of Oksanen & Virtanen (199 S). However, the occurrence of Racom itrium

lanuginosum suggests that the communit ies at Kilpisjarvi show intermediate features between the oceanic Salix

herbacea-Ochrolechia type and the subcont inental Empetrum-Cetraria nivalis type (Oksanen & Virtanen 199S).

]uncus trifidus-Cassiope tetragona type (JtCtT);

mossy, Carex bigelowii, typical (in two clusters),

graminoid, Polytrichum hyperboreum, and Cetrariella

delisei variants

The community clusters JtCtTm, JtCtTCb, JtCte, JtCtTf, JtCtTg, JtCtTPh and JtCtTCd lie in the centre of the ordination space (Fig. Sa), together, they seem to correspond to the ]uncus trifidus-Cassiope tetragona type of Oksanen & Virtanen (199S). These communities share largely the same diagnostic features: i.e. the f ie ld layer dominated by ]uncus trifidus, alone or together with Cassiope tetragona, Festuca ovina, and/or Salix herbacea.

The bottom layer is r ich in Cetraria ericetorum, C.

islandica, and/or Flavocetraria nivalis. The clusters over-


Fig. 9. Middle oroarctic Empetrum-Cassiope tetragona heath vegetation. Mt. Jehkats W-slope 900 m. In the centre Racomitrium lanuginosum fairly abundant. June 1 988. (Photo: Risto Virtanen.)

lap with each other showing some ecological variation with respect to the fust two ordinat ion axes. Cluster JtCtTg is more distant from the other clusters and are placed relatively close to eutrophic Festuca ovina

Potentilla crantzii heaths (the Festuca ovina-Potentilla

crantzii group). We are apt to retain a collective classificat ion and use the separate community clusters mainly for the ecological characterization.

]uncus trifidus-Cassiope tetragona type, Carex bigelowii

variant (JtCtTCb)

This community is characterized by patchily occurring Cassiope tetragona and ]uncus trifidus, occasionally also Empetrum, while Carex bigelowii is found more constantly with a cover of 2-3%. In the bottom layer characteristic l ichens include Cetraria ericetorum, Cladina arbus

cula (mainly C. arbuscula ssp. mitis), and Stereocaulon

spp. A typical hepatic species is Anastrophyllum minutum.

In the ordination, this community cluster is relat ively close to the Empetrum-Flavocetraria nivalis type (EFnT) and could represent an intermediate community between

the dwarf shrub heaths and the grarninoid-rich communit ies of the ]uncus trifidus-Cassiope tetragona type (Oksanen & V irtanen 1995). The intermediate community may represent a successional stage developed under influence of re indeer trampling, as suggested by a relatively high cover of Carex bigelowii as well as by rich eooccurrence of small hepatics mixed within a thinned l ichen cover. This community is referred to as the Carex

bigelowii variant of the ]uncus trifidus-Cassiope tetragona

type.

]uncus trifidus-Cassiope tetragona type, typical vari

ant (JtCtTe, JtCtTf)

These two community clusters produced by TWINSP AN are relatively s im ilar in their species compositions . Both clusters have Salix herbacea with relatively h igh cover values, with at least some Cassiope tetragona (Fig . 1 0) . One of the clusters, JtCtTe, is rich in ]uncus trifidus and the other, JtCtTf, r ich in Festuca ovina . These communit ies resemble the ]uncus trifidus-Cassiope tetragona type in Oksanen & Virtanen ( 1995). However, none of the



Fig. 1 0. ]uncus trifidus-Cassiope tetragona type heath vegetation. Mt. Guonjarvam. Alt. 960 m. July 1989. (Photo: Risto Virtanen.)

variants described there is conspicuously simi lar in species abundance re lationships. These two communities show more c learly affinities to the northern and oceanic counterpart of Juncion trifidi, i.e. the Salix herbacea

Empetrum type (Oksanen & Virtanen 1995). On the other hand, the luncus trifidus-rich community (JtCtTe) is much like the ']uncus trifidus-grashei ' described by Nordhagen (1943: 219-220) from Rastigaissa at interior Finnmark. Th is suggests that these two c lusters may represent the typical, but local ly variable, elements of ch ionophilous vegetation on subcontinental mountains of northwestern Fennoscandia.

]uncus tri.fidus-Cassiope tetragona type, graminoid

variant (JtCtTg)

This community has a relat ively sparse field layer with about equally abundant Festuca ovina and luncus trifidus.

Evergreen dwarf shrubs are only sporadical ly present. In the cryptogam layer, Polytrichaceae mosses (Polytri

chastrum alpinum and Polytrichum piliferum) are relat ively abundant. In Oksanen & Virtanen (1995), the c losest counterpart is the Festuca ovina variant of the ]uncus

trifidus-Cassiope tetragona type. However, scattered Erigeron uniflorus and Minuartia biflora indicate a cer-


tain influence of calc ium carbonate. In the ordination (Fig. 15a), this community is about intermediate between the clusters of the Festuca ovina-Potentilla crantzii group and the other clusters of this group. This community is also p laced c lose to c luster JtCtTm in the ordinat ion but has a lower cover of Cassiope tetragona. This community cluster could be regarded as a grarninoid variant of the JtCtT between the typical variants of the type and the Festuca ovina-Potentilla crantzii group.

]uncus tri.fidus-Cassiope tetragona type, Polytrichum

hyperboreum variant (JtCtT Ph)

This community is re latively open and characterized by Cassiope tetragona and ]uncus trifidus growing in spaced patches. The cryptogam layer is rich in Cetrariella delisei,

Cetraria ericetorum, and C. islandica ssp. crispiformis,

Polytrichum hyperboreum, often encrusted with Ochro

lechiafrigida (mean cover 25 %). In its species composition this community resembles fairly well the Trientalis

variant of the ]uncus trifidus-Cassiope tetragona type in Oksanen & Virtanen (1995). However, in our material Trientalis europaea is absent, and chionophobous l ichens such as Alectoria nigricans and A. ochroleuca occur w ith lower covers than in the Trientalis variant. The sample


ShKIT ShChT ShKITCb CbT ChJtT C hJtT CbSpT JtCtTCd TsSaT

Fig. 1 1 . TWINSPAN divisions of the Salix herbacea group. CbT - Carex bigelowii type, CbSpT - Carex bigelowii-Salix polaris type, ChJtTe/ChJtTf - Cassiope hypnoides-Juncus trifidus type, JtCtTCd - ]uncus trifidus-Cassiope tetragona type, Cetrariella delisei variant, ShChT - Salix herbacea-Cassiope hypnoides type, ShKiT - Salix herbacea-Kiaeria type, ShKiTCb - Salix herbacea-Kiaeria type, Carex bigelowii variant, TsSaT - Trisetum spicatum-Sanionia type.

plots assigned to this cluster were encountered on sloping sites with gravelly soil where reindeer trampling is intense. The relatively high cover of Polytrichum

hyperboreum is regarded as an indication of reindeer trampling (Oksanen & Virtanen 1995). Thus, this variant community obviously represents a trampled stage of the }uncus trifidus-Cassiope tetragona type on relatively high altitudes and on nutrient-poor hill slopes.

]uncus trifidus-Cassiope tetragona type, Cetrariella

delisei variant (JtCtT Cd)

This cluster characterized by Cassiope tetragona with Cetrariella delisei was assigned to the group of moderate snowbed communities . However, in its species composition this community resembles more closely the vegetation of the }uncus trifidus-Cassiope tetragona group than snowbeds. The high cover of Cetrariella delisei may be related to its tolerance to freezing in solid ice (Dahl 1957; Oksanen & Virtanen 1995) . Such ice formation is likely to occur in relatively level habitats, in which this community was encountered on Mt. Guonjarvarri. The formation of ice lenses may explain the sparse field layer. Cassiope

tetragona itself can elevate shoots several centimetres above the ground, and thus partially avoid freezing damage. The freezing in solid ice is probably an important ecological factor, but as yet little known (cf. Oksanen & Virtanen 1995). Due to the occurrence of Cetrariella

delisei this type is described as the Cetrariella delisei

variant of the }uncus trifidus-Cassiope tetragona type.

3.1.4 Salix herbacea group

Moderate-late snowbed vegetation; Appendix 4, Fig. 1 1

This group comprises a series of snowbed communities apparently from a wide array of ecological conditions related to the length of a snow-free period. Three of the community clusters, ShK.iT, ShChT, and ShK.iTCb, are characterized by Salix herbacea and Cassiope hypnoides,

corresponding to the traditional Cassiopeto-Salicion

herbaceae (Nordhagen 1943) and the Salix herbacea

Kiaeria group in Oksanen & Virtanen (1995). These communities seem to be differentiated regarding the length of the snow-free period and moisture conditions. One of the remaining clusters, CbT, includes snowbeds dominated by Carex bigelowii, and thus corresponds to the vegetation found in the traditional group Nardeto-Caricion

rigidae (Nordhagen 1943). Some of the communities, ChJtTe and ChJtTf, seem to change gradually towards the upper oroarctic vegetation resembling the Luzuleto

Cesietum (Dahl 1957: 169-176) or the Luzula confusa

group in Oksanen & Virtanen (1995) . The positive branch of the TWINSP AN tree includes two clusters where the communities have many indicators of nutrient-rich site conditions. The first of them, cluster TsSaT, might be best characterized as eutrophic snowbed vegetation . This vegetation shows affinity with the Ranunculeto-Oxyrion

(Nordhagen 1943) or with the Ranunculus glacialis group in Oksanen & Virtanen (1995). The second cluster, CbSpT,



resembles to a large degree the herb-rich vegetation of Carex bigelowii-Salix polaris type (Oksanen & Virtanen 1 995). The vegetation types of this group can be described as follows :

Salix herbacea-Kiaeria type (ShKiT)

This community is characterized by Salix herbacea and Kiaeria starkei occurring with high cover. Gnaphalium

supinum and Sibbaldia procumbens are regular constituents with low cover. The cryptogam layer is rich in hepatics (Barbilophozia subgenus Orthocaulis, Lophozia

spp.) and snow bed mosses (e.g. Conostomum tetragonum).

This cluster occurs at the relatively extreme end of the snow gradient (Fig. Sa). This community cluster corresponds to the 'Salix herbacea-Kiaeria starkei-Polytrichum

sexangulare-sosiasjon ' of Nordhagen ( 1 943) and the Salix

herbacea-Kiaeria starkei-sociation of Gjrerevoll ( 1 956).

This community is similar to the Salix herbacea-Kiaeria

type described in Oksanen & Virtanen ( 1 995).

Salix herbacea-Cassiope hypnoides type (ShChT)

This type differs from the Salix herbacea-Kiaeria type above by having a relatively high coverage of Cassiope

hypnoides (almost lacking in the Salix herbacea-Kiaeria

type). The bottom layer is richer in lichens (Cetraria

ericetorum, C. islandica ssp. crispiformis, and Cladonia

coccifera), while Kiaeria starkei is almost absent, and Polytrichum spp. are more common than in the Salix

herbacea-Kiaeria type. The Salix herbacea-Cassiope

hypnoides type prevails on sites with a longer snow-free period than on the sites of the Salix herbacea-Kiaeria type. The Salix herbacea-Cassiope hypnoides type corresponds well to some samples of 'moselyngsnOleier ' ( Cassiopetetum

hypnoidis) in Nordhagen ( 1 943 : 262) and the Salix herbacea

Cassiope hypnoides type in Oksanen & Virtanen ( 1 995). It also resembles the Cassiope hypnoides-Antheliajuratzkana

Gymnomitrion varians-sociation in Gjrerevoll ( 1 956), but the cover values of the small hepatics are remarkably lower than in Gjrerevoll 's material.

Salix herbacea-Kiaeria type, Carex bigelowii variant

(ShKiTCb)

This community cluster is dominated by Salix herbacea,

and also Carex bigelowii is relatively abundant, too. This differs from the Salix herbacea-Cassiope hypnoides type in having a low coverage of Cassiope hypnoides. The cryptogam layer is characterized by a thin hepatic layer (total cover 1 5-20 % ) . The typical species include Anastrophyllum minutum, Gymnomitrion apiculatum, G. concin

natum and Lophozia spp. A typical lichen is Cetrariella

delisei, but its cover is low (about 2 % ). It seems that the community is related to Salix herbacea snowbeds (association Salicetum herbaceae Gjrerevoll 1 956: 1 06, the


'mosrik Salix herbacea-sosiasjon ' Nordhagen 1 943: 266),

but no samples with a conspicuously similar community composition were found. Indeed, this may represent an intermediate community between the Salix herbacea and Carex bigelowii snowbeds. Thus, we consider the type as a Carex bigelowii variant of the Salix herbacea-Kiaeria

type, where the abundance of Carex bigelowii indicates moister site conditions than in the sites of the main type.

Carex bigelowii type (CbT)

This community is characterized by a rather uniform cover of Carex bigelowii (mean cover about 1 3 %) ; Salix

herbacea has a relatively low cover giving a more meadowlike appearance. Other characteristic species in the field layer are Bistorta vivipara and Cassiope hypnoides. In the cryptogam layer Anthelia juratzkana and Conostomum

tetragonum are frequent indicating true snowbed conditions. This type is often encountered in sites periodically irrigated by melt water of snow fields. This vegetation corresponds to the 'Carex rigida -Ass. ' (Nordhagen 1 928),

the ' Carex rigida-Wiese ' ( Kalliola 1 939) and the ' Carex

rigida-Lachenalii-sosiasjon' of Nordhagen ( 1 943 : 250-

260). In Gjrerevoll 's ( 1 956) material, the closest counterparts are found among Carex bigelowii -sociations, but none of his samples resembles ours. This type was not encountered in the data of Oksanen & Virtanen ( 1 995) . A reason may be that the Carex bigelowii snowbeds prevail on relatively level ground in mountain valley bottoms and usually they are not found in sloping ridge-depression topographic transects.

Cassiope hypnoides-Juncus trifidus type (ChJtTe,

ChJtTf)

There is a pair of clusters, ChJtTe and ChJtTf, characterized by a relatively high abundance of Cassiope hypnoides,

Luzula arcuata ssp. confusa and/or ]uncus trifidus in the field layer, while the cryptogam layer is covered chiefly by Gymnomitrion spp. Among the lichens Cetrariella

delisei is relatively abundant. In our material, the samples are from relatively level plateaux with polygon fields, chiefly on Mt. Gahpperus. The polygons are more or less active which may increase the vegetational heterogeneity. Overall, these communities resemble much the Cassiope

hypnoides-Juncus trifidus type in Oksanen & Virtanen ( 1 995). The other community, ChJtTe, resembles in its species composition the 'Ranunculus glacialis-Luzula

confusa-Anthelia-Cesia-sosiasjon' of Nordhagen ( 1 943 :

27 1 -278). The abundance of R. glacialis is lower in our material than in Nordhagen 's. The other community, ChJtTf, resembles the Luzuleto-Cesietum ( Dahl 1 957),

but it has a conspicusously higher cover of Cassiope

hypnoides (almost lacking in Dahl 's material) and lesser Polytrichastrum sexangulare than is found in Dahl ' s descriptions. The variations in the abundance relationships of species may reflect a patchy plant cover typical at


altitudes of about 1 000- 1 100 metres where the middle

oroarctic zone is connected to the upper oroarctic zone.

Carex bigelowii-Salix polaris type (CbSpT)

This community is characterized by Carex bigelowii,

Festuca ovina, and Salix herbacea which are frequently mixed with indicators of calcareous substrate (e.g. Silene

acaulis and Salix polaris). The field layer includes a

conspicuously large number of arctic-alpine herbs (e.g.

Antennaria canescens, A. porsildii, Cerastium arcticum,

Erigeron uniflorus, and Ranunculus n ivalis ) . The

cryptogam layer is rich in lichens, but only Cladina

arbuscula ssp. mitis, has a relatively high cover. Cetra

riella delisei and Cladonia uncialis are characteristic

species. The cover of lichens is obviously decimated by

reindeer grazing. In the ordination (Fig. Sa), the commu

nity is close to the heath-like Salix herbacea snowbeds (ShChT, ShKiTCb) . This community has some affinity

with the Cassiope tetragona-Dryas heaths described as the Cassiopetum tetragonae dryadetosum by Nordhagen

( 1 9SS) . This community also resembles some of the

sample plots of the Polygoneto-Salicetum herbaceae

(Dahl 1 9S7 : 1 78- 1 88) . Dahl ( 1 9S7) describes this veg

etation type as eutrophic, seasonally wet and late

snowbed, frequently with signs of solifluction. This

characterization is fairly similar to the description of a

species-rich type described by Oksanen & Virtanen

( 1 99S) near the limit of continuous plant cover: The

Carex bigelowii-Salix polaris type was characterized as

'alpine garden ' owing to soil conditions enriched by

nutrient supply from (periodic) surface water flush or

groundwater. Aesthetically attractive communities can

be found at such places. The community cluster can be

regarded as a well-drained and relatively lichen-rich

(continental) variant of the Carex bigelowii-Salix pola

ris type.

Trisetum spicatum-Sanionia type (TsSaT)

This community cluster represents meadow-like snow bed

vegetation with herbs (Ranunculus acris ssp. pumila, R.

Fig. 1 2. TWINSPAN divisions of the Ranunculus glacialis group (a) APsT -Anthelia juratzkana-Polytrichastrum sexangulare type, KPC - Koenigia islandica-Phippsia algida community, and Saxifraga oppositifolia group (b) DocCtT - Dryas octopetala-Cassiope tetragona type , SpSacT - Salix polaris-Silene acaulis type, SoppRsT - Saxifraga oppositifolia-Ranunculus sulphureus type.

APsT

nivalis, and Sibbaldia procumbens) and graminoids (Car ex

lachenalii and Trisetum spicatum) . The abundance of C. lachenalii is high compared to that of C. bigelowii. In the

bottom layer Sanionia uncinata is abundant. In the ordi

nation (Fig. Sa) it has a position close to the Festuca

ovina-Potentilla crantzii heaths. As compared to Gjrere

vol l ' s ( 1 9S6) classification, this community falls between

the alliances Deschampsio-Anthoxanthion and Ranunculo

Anthoxanthion, and no similar sociation can be found in

his material. Rather, this community can be regarded as

similar to the Trisetum spicatum-Sanionia type in Oksanen

& Virtanen ( 1 99S).

3.1.5 Ranunculus glacialis group

Oligotrophic late snowbeds; Appendix 5, Fig. 12a

This group embraces a pair of community types repre

senting separate higher level vegetation units. One of the

communities, cluster APsT, is a cryptogam-dominated

snowbed which could be included in the traditional alli

ance Polytrichion norvegici (Gjrerevoll 1 9S6) or Ranun

culus glacial is group of Oksanen & Virtanen ( 1 99S). The

other community, cluster KPC, resembles the meadow

like snowbed communities in the alliance Ranunculeto

Oxyrion ofNordhagen ( 1 943) or the Oppositifolio-Oxyrion

of Gjrerevoll ( 1 9S6).

Anthelia juratzkana-Polytrichastrum sexangulare type

(APsT)

This community is dominated by cryptogams, of which

Anthelia juratzkana and Polytrichastrum sexangulare are

the most prominent species. Vascular plants include Gnaphalium supinum and Ranunculus nivalis (more rarely

R. glacialis), and e.g. Salix herbacea is absent. This

community is encountered near the latest snow fields

emerging from snow in late July or August and changes

into the less extreme snowbed communities where also

vascular plants, e .g . Oxyria digyna and Ranunculus

b)

0.3 1 6

KPC

SpSacT SoppRsT DocCtT



glacialis, become more abundant. The community cluster

resembles the association Ranunculetum glacialis in Gj rerevoll ( 1 956 : 1 36) or the Ranunculus glacialis

Gymnomitrion type of Oksanen & Virtanen ( 1 995). How

ever, this cluster represents the most extreme snowbeds

that are virtually devoid of vascular plants and is thus

described as the Anthelia juratzkana-Polytrichastrum

sexangulare type, also found at relatively high altitudes in

the oceanic sectors of northern Norway (Virtanen et al.

unpubl. data).

Koenigia islandica-Phippsia algida community (KPC)

This community cluster represents a distinct community

characterized by a hydrophilous moss Wamstorfia exan

nulata growing in mats on which e.g. Saxifraga stellaris

frequently flourishes. Anthelia juratzkana and Pleuro

cladula albescens are characteristic hepatics. This com

munity resembles Gjrerevoll ' s ( 1 956 : 356) Phippsia

algida-sociation, but the coverage of herbs in the field

layer is lower in his material. Due to scanty material (only

two sample plots in this cluster), our characterization has

to be regarded as tentative.

3.1.6 Saxifraga oppositifolia group

Moderate-late snowbeds on calcareous substrates;

Appendix 6, Fig. 1 2b

This community group represents vegetation on calcare

ous soils along a gradient from the sites with moderate

snow cover to the sites with late snow. In the TWINSP AN

analysis, three community clusters were recognized. One

of the community clusters, DocCtT, is placed relatively

close to the Dryas octopetala-Carex rupestris type (Fig.

5a). The two remaining community clusters, SpSacT and SoppRsT, are noted among the sites with late-lying snow.

In terms of species composition, these snowbed commu

nities are related to Gjrerevoll ' s ( 1 956: table 59) alliance

Oppositifolio-Oxyrion.

Dryas octopetala-Cassiope tetragona type (DocCtT)

This community is clearly dominated by Dryas octopetala

and Cassiope tetragona. In smaller amounts, but con

stantly, Salix polaris, S. reticulata, Saussurea alpina

and Thalictrum alpinum occur. Cetraria ericetorum and

C. islandica are relatively abundant while Mnium blyttii

is one example of many calciphilous mosses. This com

munity resembles the association Cassiopetum tetragonae

dryadetosum of Nordhagen ( 1 955), but in Nordhagen ' s

sample material Hylocomium splendens dominates the

ground layer (not at all in our material ) . This community

can be interpreted as a middle oroarctic counterpart of

Bringer' s ( 1 96 1 ) Tetragono-Dryadetum alectorietosum

described from northern Sweden. The counterpart de-


scribed by R�nning ( 1 965) from Spitsbergen is the

Tetragono-Dryadetum. R�nning considers this type simi

lar to Nordhagen' s Cassiopetetum tetragonae drya

detosum. In the numerical TWINSP AN classification,

the vegetation of this group of northern Fennoscandia

and Spitsbergen is well differentiated. The difference is

distinct in the cryptogam layer: on Spitsbergen, mosses

such as Aulacomnium turgidum, Hylocomium splendens

var. alaskanum, Oncophorus wahlenbergii, Sanionia

uncinata and Tomentypnum nitens are frequent and of

ten also abundant.

Salix polaris-Silene acaulis type (SpSacT)

In this community, the most abundant species are Salix

polaris and Silene acaulis. Other characteristic species

include Cerastium arcticum, Oxyria digyna and Saxifraga

cemua. In the field layer, there are small herb species that

do not typically occur in the latest snow beds (e.g. Anten

naria porsildii, Erigeron uniflorus and Gnaphalium

supinum) . The cryptogam layer is rich in moss and lichen

species, and none of the species has a dominant position.

The closest counterpart in Gjrerevoll ' s material is found

in the association Oppositifolietum. Some sample plots

from Swedish Tome Lappmark (Gjrerevoll 1 956: table

59, column 8) are rather similar, but such species as

Sauteria alpina are missing in our material. This commu

nity, overall, does not conform with the Oppositifolietum

of Gjrerevoll ( 1 956). It thus appears that this community

could then be described as a new vegetation type in order

to characterize the vegetation on moderate snowbed sites

on calcareous substrates. This type of vegetation occurs in

concave terrains in typical snow accumulation sites, but at

higher altitudes also on relatively convex mountain slopes

(e.g. on the southern slopes of Mt. Pihkahistama, northern Norway, own observations).

Saxifraga oppositifolia-Ranunculus sulphureus type

(SoppRsT)

At first sight, this vegetation may give an impression of

a barren ground devoid of any higher plants. Indeed, the

field layer is poor, but after close examination many

species can be found (Fig . 1 3) . The most characteristic

species are Equisetum variegatum, Ranunculus sulphu

reus, and Saxifraga oppositifolia. The moss cover is not

thick, but many small acrocarpic species occur and may

reach covers of a few percentages (e.g. Distichium

capillaceum, Fissidens osmundoides, Meesia uliginosa

var. arctica, Tortella fragilis and Tortula norvegica) .

Among the mosses there may be some rare species (e.g.

Tayloria froelichiana) . The calcicolous lichen Solorina

bispora is rather constant . This community is clearly

calcitrophic and usually found in terrain with calcareous

outcrops. The closest counterparts in Gjrerevoll ' s ( 1 956)

descriptions are found among the associations Oppositi

folietum and Ranunculetum nivalis. However, the units


Fig. 1 3 . A snowbed of Saxifraga oppositifolia-Ranunculus sulphureus type. Mt. Guonjarvarri . Alt. 950 m. July 1 989. (Photo: Risto Virtanen.)

of Gjrerevoll are relatively narrow. It seems that this

cluster can be described as a new type. This type, to be

called the Saxifraga oppositifolia-Ranunuculus sulphu

reus type, is relatively broad, containing both snowbeds

characterized by Ranunculus sulphureus and by Saxifraga

oppositifolia. This community type shows a transition to

the Salix polaris-Silene acaulis type without any distinct

border; it also shows a transition to the most extreme

snowbed community characterized by scattered Sagina

n ivalis and Saxifraga tenuis, or by cryptogams only.

3.2 Spitsbergen

In the Spitsbergen data, the first TWINSP AN division

allocated the material into two main groups: ( 1 ) heath-like

vegetation characterized by Dryas octopetala, Luzula

arcuata ssp. confusa and/or Salix polaris, and (2) moss

dominated tundra and snowbed vegetation (Fig. 4). The

former main group was then divided into three groups

differentiated along topographic and edaphic gradients,

and to some extent along a regional (climatic) gradient.

The divisions result in the Luzula confusa group, the

Papaver dahlianum group and the Dryas octopetala group.

The latter main group was divided into three groups: wet

moss snowbeds, snowbed communities dominated by

Sanionia (the Sanionia snowbed communities) and moss

tundra communities dominated by robust mosses other

than Sanionia. Consequently, the Spitsbergen material is

summarized in six community groups containing alto

gether 1 6 community types or variants.

The main gradient structure of the Spitsbergen mate

rial resembles that of northern Fennoscandia (Fig. 1 4) .

The first DCA axis can be related to unequal snow distri

bution, as the snowbed sites with copious moss communi

ties are placed to the left and the deflation heaths with

poor plant cover lie to the right. On Spitsbergen, the

topographic gradient is related except for differential snow

depth and permafrost, as the depth of the active layer

varies along the topography (Eurola 1 968; R0nning 1 969;

SUiblein 1 97 1 ) . This influences the temperatures in

rhizosphere and moisture conditions: on slopes the melt

water seeps to grounds irrigating the soil surface during

the vegetation period. The second gradient is not easy to

interpret. The communities at the other end of the gradient

are characterized by Cassiope tetragona, Dryas octopetala



and Bistorta vivipara. The mosses Hylocomium splendens

var. alaskanum and Tomentypnum nitens indicate nutri

ent-rich soil conditions relatively favourable conditions

of the inner fjord region. The other end of the second

gradient is occupied by communities characterized by

Cetrariella delisei and Racomitrium lanuginosum. The

community clusters with copious occurrence of R. lanu

ginosum originate from the southwestern coastal region,

and Papaver dahlianum communities prevail in climati

cally cold areas (Kjellstrom-Agardhdalen area). Conse

quently, the second gradient can be expected to reflect

both climatic and edaphic differentiation (gradient termed

'edaphic favourableness' ) . Due to regional differentiation

of the vegetation on Spitsbergen, the number of sample

plots in each of the three subareas (west-southwestern

coastal region, inner fjord region and Dryas region) are

indicated in the community descriptions. The regions are

abbreviated as C:I :D, respectively, followed by the number

of sample plots .

3.2.1 Luzula confusa group

Chionophobous-chionophilous heaths rich in bryophytes

and lichens; Appendix 7, Fig. 15a

This community group consists of three community clus

ters that are characterized by relatively high covers of

Cetrariella delisei, Luzula arcuata ssp. confusa and Salix

polaris. The moss layer is strongly fragmented with

Racomitrium canescens, R. lanuginosum, and Sanionia

uncinata as chief constituents with varying abundances in

the community types. This group of communities is diffi

cult to compare with any of the traditional alliances re

viewed by Elvebakk ( 1 994). In Eurola ( 1 968) this group

represents chiefly the 'Flechtenheide' vegetation of the

western coast (Cladina mitis region). The closest counter

parts can be found in the alliance Luzulion arcuatae

representing vegetation on moderate ridges with acidic

substrates. The clusters LcGC and LcRlC seem to repre

sent chionophobous communities, and LcSaC occupies

more sheltered sites (Fig. 1 4) .

Luzula confusa-Gymnomitrion corallioides community

(LcGC)

This community is characterized by Luzula arcuata ssp.

confusa and Salix polaris occurring with about equal

cover ( 1 1 - 1 2 %, on average). The bottom layer is chiefly

characterized by Cetrariella delisei and Sanionia unci

nata. Moreover, Gymnomitrion corallioides is relatively

abundant. The total number of species is high, but many

of them occur irregularly which may partly be due to a

mosaic vegetation structure created by polygon activity

(Fig. 1 8a). The less active polygon centres are colonized

by G. corallioides, and the interspaces have a more


4 ,3------�.-------.-------�--------.

3

+ C\1

! I 1.{) V e, 2 N } < 0

j 0 "i

2 3 4

DCA 1 (0.539)

Fig. 1 4a.

closed plant cover. In its floristic composition this com

munity seems to correspond partly to the Luzulo confusae

Salicetum polaris Hadac (Hadac 1 989). However, the

character species mentioned by Hadac ( 1 989) include

A nastrophyllum m inutum , Kiae ria glacialis and Tritomaria quinquedentata which are not characteristic

in our material. This type vegetation is wide-spread on

Spitsbergen C : I :D= 1 :4 :2 .

Luzula confusa-Racomitrium lanuginosum community

(LcRIC)

This community is characterized by patches of Raco

mitrium lanuginosum and a more uniformly developed

vegetation of Cetrariella delisei. In the field layer,

Saxifraga oppositifolia is the most prominent species,

while Cardamine bellidifolia is a characteristic subdomi

nant. In the ordination this community is placed among

chionophobous clusters with infertile soils (Fig. 1 4) . In its

species composition, this community seems to resemble

the Cetrariella delisei-Saxifraga oppositifolia tundra

(Nimis 1 985), included in snowbed communities of the

Luzulion nivalis by Elvebakk ( 1 994), but Racomitrium

lanuginosum occurs only scarcely. Elvebakk regarded it

ecologically as moderate snowbed. However, the occur

rence of Racomitrium lanuginosum suggests that this

community is chionophobous. On these grounds, this

community seems to correspond to vegetation in the Sphae

rophoro-Racomitrietum lanuginosi (Hofmann 1 968). It is

ecologically related to the R. lanuginosum dominated

communities which on Spitsbergen seem to be confined

-.] .5


..

.. Dry oct

.. Tom nit

Pol viv • • Hyl ala

.. ste riv

.. Aul tur • Alo alp

.. • Oxy dig Pol arp

.. Ste alp

.. Cer arc

.. Luz arc

.Pti cil • Die fus

•Rac can

•Cas tet

• Poa arc

• Hyp rev

L� con .. .. Pso hyp Bry sp

• Sax ces Och fri • .. Sax opp

Cet isl

GyDJ cor

Rac lan .. + Cet del

•cyanoba

+4.5

Fig. 1 4. Ordination diagram of axis 1 against axis 2 using Detrended Correspondence Analysis (DCA) for the TWINSPAN groups (a:

overleaO in the material of Spitsbergen. The centroids (points) are mean sample scores for the first two DCA axes. Circled areas indicate S.D. of the scores with respect to the axes. AtAbC - Aulacomnium turgidum-Alopecurus borealis community, AtHC - Aulacomnium turgidum-Hylocomium community, DocSaC - Dryas octopetala-Sanionia community, DocSpC - Dryas octopetala-Salix polaris community, DocTC - Dryas octopetala-Tomentypnum community, LcGC - Luzula confusa-Gymnomitrion corallioides community, LcRlC - Luzula confusa-Racomitrium lanuginosum community, LcSaC - Luzula confusa-Sanionia community, PdP - Papaver dahlianum polar desert, PdRpC - Papaver dahlianum-Racomitrium panschii community, RcOxC - Racomitrium canescens-Oxyria community, SaC - Sanionia snowbed community, SaPalpC - Sanionia-Poa alpigena community, SaShypC - Sanionia-Saxifraga hyperborea community, SoppHrC - Saxifraga oppositifolia-Hypnum revolutum community . DCA ordination of the species (only most common shown) (b) Alo alp - Alopecurus borealis, Aul tur - Aulacomnium turgidum, Bry sp - Bryum spp., Cas tet - Cassiope tetragona, Cer arc - Cerastium arcticum, Cet del - Cetrariella delisei, Cet isl - Cetraria islandica, Cyanoba - Cyanobacteria, Die fus - Dicranum fuscescens, Dry oct - Dryas octopetala, Gym cor - Gymnomitrion corallioides, Hyl ala - Hylocomium splendens var. alaskanum, Hyp rev - Hypnum revolutum, Luz arc - Luzula arctica, Luz con - Luzula arcuata ssp. confusa, Och fri - Ochrolechiafrigida, Oxy dig - Oxyria digyna, Poa alg - Poa alpigena, Poa alp - Poa alpina, Poa arc - Poa arctica, Pol alp - Polytrichastrum alpinum, Pol viv - Bistorta vivipara, Pso hyp - Psoroma hypnorum, Pti cil - Ptilidium ciliare, Rac can - Racomitrium canescens, Rac lan - Racomitrium lanuginosum, San unc - Sanionia uncinata, Sar sar - Sarmentypnum sarmentosum, Sax ces - Saxifraga cespitosa, Sax opp - Saxifraga oppositifolia, Ste alp -Stereocaulon alpinum, Ste riv - Stereocaulon rivulorum, Tom nit - Tomentypnum nitens.



le GC lcRIC

b)

Le SaC

op I 0.363

4 I I PdP

c)

� I 0.305 I

8 [I] PdRpC SoppHrC

DocTC Docsac DoeS pC

Fig. 1 5a-c. TWINSPAN division.s �f a) the L

.uzula confusa group. LcGC - Luzula confusa-Gymnomitrion corallioides community,

LcRl.C - Luzula confusa-Racomltrzum

. lanugmosum community, LcSaC - Luzula confusa-Sanionia community . b) the Papaver

dahlzanum group. PdP - Papaver dahlzanum polar desert, PdRpC - Papaver dahlianum-Racomitrium panschii community. c) Dryas octopetala group. DocSaC - Dryas octop�tala-Sanionia community, DocSpC - Dryas octopetala-Salix polaris community, DocTC _

Dryas octo?etala-Tomentypnum commumty, SoppHrC - Saxifraga oppositifolia-Hypnum revolutum community . Numbers of sample plots and e1genvalues of the divisions are indicated.

to stable bouldery sites (Hartmann 1 980) and to more

oceanic parts of SW Spitsbergen (Triloff 1 944; Kuc 1 963;

Dubiel & Olech 1 990), occurring sporadically in the inner

fjord region (Hartmann 1 980) and northern parts of

Spitsbergen (Summerhayes & Elton 1 928; Brattbakk

1 983). In our material, this community was encountered

solely in the Homsund area (C: I :D=7:0:0) which further

strengthens its affinity to the oceanic Racomitrium

lanuginosum heaths (see also Virtanen et al. 1 997b) .

Luzula confusa-Sanionia community (LcSaC)

In the field layer of this community, Luzula arcuata ssp.

confusa is the most conspicuous species, and Salix polaris

reaches a mean cover of about 1 0%. In the cryptogam

layer Cetrariella delisei is only a minor constituent, while

Sanionia uncinata has a relatively high cover. Among

other mosses, Dicranum angustum and Hylocomium

splendens var. alaskanum are common. The community

seems to be more mesic in its species composition than the

two other communities in this group, and it is also placed

close to the moss tundra communities in the ordination

(Fig. 1 4). This community has a distribution with a centre

of occurrence in the coastal areas (western Isfjorden and

Homsund). C : I :D=3 :3 :0.


3.2.2 Papaver dahlianum group

Polar deserts and associated ridge communities; Appendix

8, Fig. 15b

This community group with two community clusters repre

sents the vegetation approaching vegetation of polar deserts

(Bliss et al . 1 984; Aleksandrova 1 988). At frrst sight, the

species composition and abundance relationships of the

two clusters seem to differ clearly from the rest of the

Spitsbergen material, thus it is surprising that they do not

fall into any extreme position in the ordination, but that they

lie between the Luzula confusa group and the Dryas

octopetala group. Soil movements combined with abrasive

winds are probably responsible for the sparse vegetation,

and these sites are also exposed to the coldest winter

conditions. At certain places in winter time, reindeer is

searching for food from sites with a thin snow cover, and

therefore grazing can also have a local impact on these

communities. The two clusters in this group are differenti

ated alike with regard to soil stability (intensity and fre

quency of cryoperturbation). These two clusters are best

understood as fixed points in a continuum from more or less

barren ridges to more closed communities on hill slopes.

Papaver dahlianum polar desert (PdP)

The total vegetation cover of this community cluster is


about 1 0% on average. The plant debris consists of Draba

spp. , Luzula arcuata ssp. confusa, Papaver dahlianum,

Poa arctica, and Potentilla hyparctica. Scatteredly grow

ing Tortula ruralis is a typical moss, while this commu

nity is devoid of any robust mosses. The occurrence of

such mosses is probably prevented by a high disturbance

rate. Among lichens, Cladonia pocillum is characteristic.

This community corresponds quite well to the Papaveretum

dahliani typicum (Hofmann 1 968) or to the Papaverion

dahliani (Hadac 1 946) . It is similar to the Papaver

dahlianum polar desert described from altitudes of 400-

600 m above sea level in the Adventdalen region (Virtanen

et al . 1 997b) . The nature of this community conforms

largely to that reported from polar deserts of Devon Is

land, Arctic Canada (Bliss et al . 1 994) . The sample plots

in this cluster were encountered in the Kjellstromdalen

Agardhdalen region. C : I :D=0:0:4.

Papaver dahlianum-Racomitrium panschii community

(PdRpC)

This community has a more closed plant cover than the

Papaver dahlianum polar desert type described above.

Here, Salix polaris, Saxifraga cespitosa, and S. opposi

tifolia are somewhat more abundant, in addition Cerastium

arcticum, Festuca hyperborea, and Minuartia rubella are

frequent. Hypnum revolutum and Racomitrium species

(Racomitrium canescens and R. panschii) occur rather

regularly . Lichen cover is also better developed than in

the Papaver dahlianum polar desert: e.g. Ochrolechia

spp. have a relatively high cover. This community repre

sents vegetation on exposed ridges showing a gradual

transition to polar desert vegetation and it corresponds to

the Papaveretum dahliani salicetosum polaris (Hofmann

1 968). This is included in the alliance Caricion nardinae

comprising vegetation on exposed ridges on alkaline and

circumneutral substrates (Nordhagen 1 936; Elvebakk

1 985, 1 994). This community is confined to the Dryas

region (Slettvika-Agardhdalen), C : I :D=0:0:4.

3.2.3 Dryas octopetala group

Xeric Dryas-bryophyte heaths; Appendix 9, Fig. 15c

The three community clusters, DocTC, DocSaC and

DocSpC, assigned to this group embrace chionophobous

chionophilous vegetation characterized by Dryas octopetala

occurring with a relatively high cover of 1 5-25%. The three

clusters overlap broadly in the ordination (Fig. 1 4), while

the fourth cluster, SoppHrC, is recorded in the relatively

extreme position along the first DCA axis indicating its

chionophobous nature. In this community, D. octopetala

has a low cover. Instead, many calciphilous plants thriving

on exposed ridges, e.g. Minuartia rubella, Saxifraga

jlagellaris and Silene furcata are characteristic.

The three clusters rich in Dryas octopetala can be

related to R�nning' s ( 1 965) classification scheme of the

Dryadion . He recognizes four communities: Nardino

Dryadetum, Rupestri-Dryadetum, Polari-Dryadetum, and

Tetragono-Dryadetum, differentiated chiefly in relation

to topographic position. The Nardino-Dryadetum and

Rupestri-Dryadetum communities appear to be missing in

our data. Community clusters resembling only the

chionophilous communities, the Polari-Dryadetum and

the Tetragono-Dryadetum, can be recognized. However,

the TWINSP AN analysis produced compositionally some

what different communities as compared to the descrip

tions of R�nning ( 1 965).

Dryas octopetala- Tomentypnum community (DocTC)

This community has a well-developed moss layer with

Aulacomnium turgidum, Hylocomium splendens var.

alaskanum and Tomentypnum nitens as the main constitu

ents (Fig. 1 6) . The most prominent vascular plants are

Dryas octopetala, Luzula arcuata ssp. confusa and Salix

polaris. The community roughly corresponds to the asso

ciation Cassiopo tetragonae-Dryadetum octopetalae

(Hadac 1 946; R�nning 1 965), partly to the Tomenthyp

netum involuti (Hadac 1 946) and to the Homalothecium

nitens-Dryas type of Elvebakk ( 1 994). This community is

relatively wide-spread on Spitsbergen C: I :D=0: 3 :4.

Dryas octopetala-Sanionia community (DocSaC)

This community resembles the DocTC in its species com

position, but Sanionia uncinata dominates the bottom

layer and Tomentypnum nitens is a subdominant. As sug

gested by the abundance of S. uncinata and its position in

the ordination (Fig. 1 4) , this community seems to repre

sent an intermediate type between moss tundra communi

ties and communities of the Dryas octopetala group.

There seems to be no counterpart described earlier. This

community is largely restricted to the inner fjord region

(the Adventfjorden-Sassendalen areas). C : I :D=0:9 : 1 .

Dryas octopetala-Salix polaris community (DocSpC)

Dry as octopetala and Salix polaris characterize the field

layer. Some of the sample plots have Cassiope tetragona

with a relatively high cover. Cerastium arctic urn occurs

with a cover of 0.5 %, and Poa arctica is frequent in

small numbers. The moss carpet is fragmented and none

of the species is very constant . Sanionia uncinata and

Tomentypnum nitens are the most abundant species. On

the basis of the ordination (Fig. 1 4) , this community is

slightly more chionophobous than the Dry as octopetala

Tomentypnum and D. octopetala-Sanionia communities

described above . This community resembles the 'Salix

polaris-Dryas octopetala -Soziat ion' of Hofmann

( 1 968 :29), and partly also the Tetragono-Dryadetum

(R�nning 1 965) . It is similar to the Dryas octopetala

Salix polaris community described in Virtanen et al.



Fig. 1 6. Dryas octopetala-Tomentypnum tundra. Adventdalen, Mt. Louisfjellet. July 1 990. (Photo: Risto Virtanen.)

( 1 997b) . It may be regarded as a community occupying

slopes with thin snow cover, chiefly in the inner fjord

region of Spitsbergen. C : I :D = 0:4 :2 .

Saxifraga oppositifolia-Hypnum revolutum community

(SoppHrC)

This is the only community assigned to this group having

Dryas octopetala in low abundance and frequency. This

community resembles to a large degree the Papaver

dahlianum-Racomitrium panschii community (see above)

in its species composition. However, in comparison,

Racomitrium canescens and R. panschii are lacking, while

indicators of calcium carbonate-rich substrate are fre

quent (e .g. Distichium capillaceum, Ditrichum flexicaule

and Encalypta spp.) . The plant cover is more closed and

e.g. Saxifraga oppositifolia has a relatively high cover.

This community can be equaled with the Saxifraga

oppositifolia-Hypnum revolutum community in Virtanen

et al . ( 1 997b) occupying ridges on moderately cryoactive

sites. It is widespread on Spitsbergen (C: I :D=0:3 :2) in

transitions from closed vegetation to open screes . It

resembles the cushion plant-lichen and cushion plant-


moss communities reported from Truelove Lowland (Muc

& Bliss 1 977), the ridge communities from Bathurst Is

land (Sheard & Geale 1 983) and the Saxifraga opposi

tifolia-Luzula confusa based community type on Alexandra

Fiord uplands, Canadian High Arctic (Batten & Svoboda

1 994) .

3.2.4Alopecurus borealis-Aulacomnium turgidum group

Moss tundra vegetation; Appendix 1 1, Fig. 1 7a

This community group consists of four community clusters

representing moss-dominated tundra vegetation. The char

acteristic moss species include Aulacomnium turgidum,

Hylocomium splendens var. alaskanum, Sanionia uncinata

and Tomentypnum nitens. In the field layer such species as

Alopecurus borealis, Luzula arctica, L. arcuata ssp. confusa

and Salix polaris are characteristic. The abundance rela

tionships of mosses vary between community types. The

mosses reach a closed cover. This vegetation is showing a

transition to the Sanionia dominated snowbeds and to the

Middle oroarctic vegetation in Finland and middle-northern arctic vegetation on Svalbard 3 1

a ) b )

SaC SePal pC

SaShypC AtAbC AtHC RcOxC

Fig. 1 7a-b. TWINSPAN divisions of: a) the moss tundra communities . AtAbC - Aulacomnium turgidum-Alopecurus borealis community, AtHC - Aulacomnium turgidum-Hylocomium community, RcOxC - Racomitrium canescens-Oxyria community, SaShypC - Sanionia-Saxifraga hyperborea community ; b) the Sanionia snowbed communities. SaC - Sanionia snowbed community, SaPalpC Sanionia-Poa alpigena community.

mossy Dryas octopetala tundras (the Dryas octopetala

Sanionia community). This is visible in the ordination (Fig.

1 4), where one of the clusters, SaShypC, is close to the

Sanionia snowbed communities, and cluster RcOxC is

placed between the Dryas octopetala group and the moss

tundra communities. The boundary between Sanionia

snowbeds and moss tundra communities is diffuse. The

Luzula confusa-Sanionia community also lies close to those

in the ordination (Fig. 1 4) . The clusters SaShypC, AtAalC

and AtHC prevail in the Sveagruva-Kjellstromdalen area.

The communities dominated by Tomentypnum nitens are

central among the moss tundra communities described

earlier from Spitsbergen (Hadac 1 946; Hofrnann 1 968;

Philippi 1 973). In our material, none of the communities is

clearly dominated by T. nitens. In our plots, T. nitens

abounds in communities of the Dryas octopetala group.

This may be due to the fact that T. nitens does not thrive in

prolonged wet conditions (Hofrnann 1 968). These condi

tions favour hydrophytic mosses such as Scorpidium

revolvens. It seems better not to emphasize the presence or

absence of T. nitens in the moss tundra communities. In this

respect, the collective treatment of moss tundra communi

ties [following Eurola ( 1 968): the 'frische Moosheiden' ] is

justifiable.

Sanionia-Saxifraga hyperborea community (SaShypC)

In this community prevalent mosses include Dicranum

angustum, Polytrichastrum alpinum, especially Sanionia

uncinata, and hydrophilous Sarmentypnum sarmentosum.

In addition, characteristic bryophyte species include

Conostomum tetragonum and Gymnomitrion concinnatum.

The field layer is sparse: characteristic species are Phippsia

algida and Saxifraga hyperborea indicating snow bed con

ditions. In the ordination, this community is placed close

to the Sanionia snowbeds (Fig. 1 4) . This is probably an

intermediate community between the moss tundra com

munities and the Sanionia snow beds (the 'Drepanocladus

uncinatus-Schneeboden ' Hofmann 1 968; Philippi 1 973).

This community is encountered in the Slettvika-Kjellstrom

dalen area, C : I :D=0:0:6.

Aulacomnium turgidum-Alopecurus borealis commu

nity (AtAbC)

In this community, the most abundant moss is Aula

comnium turgidum. Dicranum majus, Sanionia uncinata

and Tomentypnum nitens are found less frequent. Some

hydrophilous mosses such as Sarmentypnum sarmentosum

and Scorpidium revolvens are relatively frequent. This

community is likely to show a transition to the wet snow bed

communities (see below and Fig. 1 8) and is characteristic

in the Dryas region (C: I :D=0:0:4).

A u lacomnium turgidum -Hylocomium community

(AtHC)

This community resembles the Aulacomnium turgidum

Alopecurus borealis community in its species composi-



tion. These communities are also close to each other in the

ordination (Fig. 1 4) . In this community, hydrophilous

species are almost absent, instead Hylocomium splendens

var. alaskanum and Polytrichastrum alpinum occur with a

cover of 2-3%. This community, like the Aulacomnium

turgidum-Alopecurus borealis community, do not corre

spond well to the earlier descriptions of mossy tundras,

i .e. Tomentypnum nitens dominated tundras (Hadac 1 946;

Hofmann 1 968; Philippi 1 973) or dry or moist moss

heaths (Eurola 1 968). This community resembles the

Luzula confusa-Sanionia community (LcSaC, see above),

but has a relatively high cover of Tomentypnum nitens.

Moreover, the Luzula confusa-Sanionia community has

its main distribution in the coastal areas of western Isfjorden

and Homsund, whereas this community is restricted to the

Slettvika-Kjellstromdalen area (C:I :D=O: 1 :9) .

Racomitrium canescens-Oxyria community (RcOxC)

This community is also bryophyte-dominated, and now

Racomitrium canescens is the most abundant species. In

addition, Aulacomnium turgidum, Sanionia uncinata, and

Tomentypnum nitens are relatively abundant. This type of

vegetation includes sample plots with abundant Cassiope

tetragona (mean cover 20 % ). Otherwise, the field layer is

scarce: typical species are Luzula arcuata ssp. confusa,

Oxyria digyna and Stellaria longipes. Irregularly also

Draba alpina, Pedicularis lanata ssp. dasyantha and Si le ne

furcata are found. This community cannot be equaled

with the 'Racomitrium canescens-Gesellschaft ' described

by Philippi ( 1 973) from SE Spitsbergen. The community

described by Philippi is poorer in vascular plants and

represents a community on calcium-poor, dry substrate at

relatively high altitudes. This Racomitrium canescens

Oxyria community cluster partly contains early succes

sional communities near river shores on valley bottoms

(one of the plots is situated on a glacier foreland) and

partly relatively mesic chionophilous heaths on nutrient

rich sites. In the ordination, this community lies at an

intermediate position between the Dryas octopetala and

moss tundra communities (Fig. 1 4) . It is mainly found in

the inner fjord region (C:I :D=0:6: 1 ).

3.2.5 Sanionia snowbeds

Appendix 1 1, Fig. 1 7b

There are two community clusters recognized by TWIN

SPAN that are heavily dominated by Sanionia, whereas

other mosses rarely occur with covers of over 5 %. The

field layer is scarce: prostrate plants typical of snowbed

sites are creeping on the moss mat (Fig. 1 8d). Cerastium

regelii and Poa alpigena are the most characteristic spe

cies. Both of these clusters correspond to the 'Drepanocladus

uncinatus-Schneeboden ' (Hofmann 1 968; Philippi 1 973)


and to the 'Schneebodenstellen' (Eurola 1 968). Elvebakk

( 1 994) included these vegetation units in the alliance

Drepanoclado-Poion alpinae (Hadac 1 946). Relatively simi

lar communities dominated by Sanionia are found on Bear

Island (Virtanen et al. 1 997b ) .

In the ordination (Fig. 1 4), these two communities l ie

at an extreme position along the first DCA axis. They

show regional allopatry: the first (SaC) is present mainly

at the southwest-west coast area (Homsund), while the

other (SaPalpC) prevails chiefly in the Dryas region. The

two communities can thus be suggested to represent re

gional variants of a single community type.

Sanionia snowbed community (SaC)

The mean cover of Sanionia uncinata is about 60%, often

reaching 80- 1 00 %. Aulacomnium palustre, A. turgidum

and Calliergon stramineum are often present with a cover

of a few percentages. The field layer typically includes

Cerastium arctic urn, Salix polaris, Saxifraga oppositifolia

and S. rivularis. This community prevails chiefly in the

coastal areas of the Homsund region and in the mouth of

Isfjorden (C: I :D=6:2 :0).

Sanionia-Poa alpigena snowbed community (SaPalpC)

This community is closely similar to the Sanionia snow bed

community described above. The cover of Sanionia

uncinata is slightly lower (mean 45 % ). Tomentypnum

nitens is present with a mean cover of about 4 %. The field

layer is somewhat richer in its species composition: Bistorta

vivipara, Equisetum arvense and Poa alpigena and are

typical species. The dominance of Sanionia is lower, and

a grarninoid, Poa alpigena, is distinctly more abundant. One reason for the higher abundance of Poa alpigena in

the inland may be reindeer grazing. This community

prevails in the Slettvika-Kjellstromdalen region (C: I :D

=0:0: 8) where also reindeer occur, whereas in the SW

coastal area grazing is negligible (Punsvik et al. 1 980).

3.2.6 Wet moss snowbeds

Appendix 12, Fig. 4

Scorpidium revolvens-Tomentypnum snowbed community

This community cluster distinguished by TWINSP AN is

dominated by Scorpidium revolvens and Tomentypnum

nitens. Campylium stellatum, Sanionia uncinata and

Sarmentypnum sarmentosum are also relatively abun

dant. The field layer is characterized by Bistorta vivipara,

Equisetum arvense and E. variegatum, and with some

Saxifraga hirculus and S. oppositifolia . These wet

snowbeds can be expected to show a transition to the

arctic mire vegetation (Eurola 1 97 1 ) . Such gradients

have been described in northern Spitsbergen (Reindeer

Peninsula) by Dahle ( 1 983) : Sanionia communities occur


a

b

Fig. 1 8 . Tundra vegetation NE of van Mijenfjorden, near Darnesmorena. (a) Wind-exposed Luzula confusa-Gymnomitrion tundra. Polygon centres mostly plantless. (b) Aulacomnium turgidum-Hylocomium-rich tundra, with raised polygon centres. (c; overleaf)

Alopecurus borealis-Aulacomnium-rich tundra, with reticulate frost patterns. (d; overleaf) W of Darnesmorena, topographic ridgedepression transect. Above Barren communities approaching polar desert, depression Sanionia snowbed communities and wet moss communities . July 1 969. (Photos: Seppo Eurola.)



between Dryas heaths and wet snowbeds. The Sanionia

snowbeds are more hydrophytic in nature, approaching

the wet snowbeds with the mosses Pseudocalliergon

turgescens (= Scorpidium turgescens) and Scorpidium

revolvens (= Drepanocladus revolvens) as prominent

species. The latter species is frequent and abundant also

in the wet moss snow beds in the Kjellstrom-Agardhdalen


Fig. 1 8c

d

area. The wet moss snow beds are obviously wide-spread

on Spitsbergen in the inner fjord and Dryas regions

(C : I : D=0:2 :3) . Comparable moss communities are re

ported from Bathurst Island, Arctic Canada (Miller & Alpert 1 984) and from Barrow, Alaska (Rastorfer 1 978).

4 Topographic patterns: series of communities

in ridge-depression transects

Both in northwestern Fennoscandia and on Spitsbergen,

the topographic variation and consequent uneven distri

bution of snow cover and moisture account for the pri

mary pattern of vegetational variation at a given altitude

as is generally observed in the arctic and alpine environ

ments (e.g. Vestergren 1 902; Nordhagen 1 928; Dahl 1 957;

R�nning 1 969). The topographic variation gives rise to

series of communities (= community complex) from wind

exposed ridges to depressions with more or less late-lying

snow fields. In many earlier works, the community series

have been illustrated using transect data (e.g. Dah1 1 957;

Gjrerevoll 1 956; R�nning 1 969; Brossard et al . 1 984;

Oksanen & Virtanen 1 995), which makes it possible to

characterize the small-scale variation in vegetation. In

this study, focusing on larger scale patterns, the essential

features can be idealized based on ordination and classifi

cation schemes. Moreover, field notes and comparisons

with earlier l iterature have been used to increase the

understanding of the data.


In the middle oroarctic zone of northwestern Fennoscandia,

two major series of communities are recognized along a

ridge-depression transition:

( 1 )1he series on siliceous substrate. In the DCA ordination,

this series makes a cross-section from the communities of the

Alectoria group to the latest snowbed communities of the

Ranunculus glacialis group (Fig. 5, Fig. 1 9a). On wind

exposed ridges, heaths of the Empetrum-Cassiope tetragon,a

Alectoria type or the Empetrum-Cassiope tetragona type are

found. The former type represents communities with their

main distribution on continental mountains (the Empetrum

Phyllodoce-Alectoria type and the Vaccinium-Alectoria types

in Oksanen & Virtanen 1 995), while the latter type has

affinity with the suboceanic-oceanic heaths dominated by

Empetrum nigrum ssp. hermaphroditum (Haapasaari 1 988).

The occurrence of both types in the Kilpisjarvi district is not

surprising since this district is transitional between continen

tal and oceanic climate (Hamet-Ahti 1 963). Both types are

encountered on relatively stable soil substrates where dwarf

shrubs are able to reach a relatively high cover. The top

plateaux with patterned ground are characterized by the

Gymnomitrion type. In polygonal terrain, the frost boils are

often largely devoid of higher plants and colonized by

Gymnomitrion spp. and the hollows between elevations may

harbour chionophilous or even hydrophilous plants.

When the snow cover increases, cryoactivity decreases,

as well as the impact of abrasive winds; snow cover gives

protection against drought in early spring. At these weakly

chionophobous sites, the conditions are relatively favour

able, and the vegetation occupying these sites represent

the Empetrum-Flavocetraria nivalis type, wide-spread in

the subcontinental lower oroarctic zone ( = Empetrum

Cetraria nivalis type in Haapasaari 1 988; Oksanen & Virtanen 1 995: fig. 26) . In our study area, the communi

ties characterized by Empetrum nigrum ssp. herma

phroditum reach altitudes of about 950 m, extending only

sporadically to higher elevations. In northerly exposed

slopes, Empetrum heaths are confined to markedly lower

altitudes. Thus, E. nigrum ssp. hermaphroditum might be

regarded as a thermophilic species in the middle oroarctic

zone, where the presence of Cassiope tetragona suggests

a further narrowing of the habitat range.

The Empetrum-Flavocetraria nivalis type shows a

transition to the ]uncus trifidus-Cassiope tetragona type,

which represents the core of the weakly chionophilous

vegetation of the middle oroarctic zone (e.g. Nordhagen 1 943 ; Oksanen & Virtanen 1 995). The type is broad

including a wide array of ecologically differentiated vari

ant communities. In the Kilpisjarvi district, a community

with eo-occurring Cassiope tetragona and ]uncus trifidus

in the field layer, described as the typical variant of JtCtT,

is prevalent. The mixed community probably indicates

site conditions in which various factors maintain a dy

namic equilibrium between these two species, which in

principle, occupy partially overlapping ecological niches.

Both of the species are chionophilous, but C. tetragona is

weakly calciphilous (Nordhagen 1 955) and J. trifidus

strongly acidophilous (Nordhagen 1 943; Dahl 1 957). How

ever, in the ordination (Fig. 5b), a reverse pattern is

observed: C. tetragona is noted in the acidophilous area of

the ordination space, while J. trifidus is closer to the

calciphilous communities. Some other factors may thus

underlie this pattern. First, there are differences in eco

logical amplitude with respect to snow cover: J. trifidus

tolerates relatively late-lying snow conditions well (Nord

hagen 1 943; Bocher 1 963 ; Oksanen & Virtanen 1 995),

whereas C. tetragona has the highest abundance on stable

weakly snow-protected and/or sheltered slopes at lower

parts of the middle oroarctic zone. Only at such sites,

C. tetragona can monopolize the space. In extreme cases,

the only coexisting species can be mosses such as Hylo

comium splendens var. alaskanum. C. tetragona may be

sensitive to the reindeer trampling, because its stems lie



on the surface as do the stems of Empetrum nigrum ssp.

hermaphroditum (Callaghan & Emanuelsson 1 985). In

stead, J. trifidus tolerates trampling well due to its tussock

growth form with rhizomes forming a tightly packed

network of short branches. It may be that the ordination

also reflects community differentiation imposed by graz

ing pressure.

At Kilpisjarvi, the other major element of the tradi

tional Juncion trifidi (Nordhagen 1 943), the oligotrophic

Festuca ovina heaths are missing. In our material, heaths

rich in F. ovina are found at Mt. Saana, where they occupy

relatively nutrient-rich sites (the Festuca ovina-Potentilla

crantzii group). Thus, the cooccurrence of F. ovina and J.

trifidus heaths at Kilpisjarvi cannot be used as a straight

forward indication of climatic differentiation in the same

way as in the southern part of Norway where ]uncus

trifidus heaths are considered as a more oceanic vegeta

tion than F. ovina heaths (Nordhagen 1 943) .

Into the direction of delayed snow-melt, the ]uncus

trifidus-Cassiope tetragona heath vegetation gradually

changes into heath-like snow beds of the ]uncus trifidus

Cassiope hypnoides type (Oksanen & Virtanen 1 995).

This type seems to become wide-spread at higher alti

tudes and it is not a typical member of the community

series. It is likely that intensified soil cryoactivity and

solifluction fragments ]uncus trifidus and Cassiope

tetragona clones leaving space for better disturbance

adapted species such as Luzula arcuata ssp. confusa.

This type prevails in the gradient from the middle oroarctic

zone to the upper oroarctic vegetation and it often coexists

with the Cassiope tetragona-Ranunculus glacialis type found on upper oroarctic ridges (Oksanen & Virtanen

1 995).

The persistence of snow cover up to late June or early

July, gives rise to true snowbed vegetation, which is

represented by two types: the Salix herbacea-Cassiope

hypnoides type and the Salix herbacea-Kiaeria type with

its Carex bigelowii variant. The Salix herbacea-Kiaeria

type prevails on sites with later-lying snow (Oksanen & Virtanen 1 995), while the Salix herbacea-Cassiope hyp

noides type emerges earlier from the snow and changes

directly to a heath vegetation of the ]uncus trifidus

Cassiope tetragona type and to the snow bed vegetation of

lower altitudes (the ]uncus trifidus-Deschampsiaflexuosa

type and the ]uncus trifidus-Cladina mitis type, Oksanen

& Virtanen 1 995). The snowbed vegetation characterized

by Salix herbacea is found on sites that are drained during

the growing season. On sites that are irrigated by melt

water or are otherwise moist, as in some depressions with

more or less level ground, the Carex bigelowii type (CbT)

prevails. Moreover, these Carex bigelowii snowbeds

emerge earlier from snow as they usually are situated

away from the latest snow-fields (Nordhagen 1 928). On

intermediate sites, one can encounter the Carex bigelowii

variant of the Salix herbacea-Kiaeria type.


In sites adjacent to the latest snow fields, still existing

in the turn of July-August, the abundance of cryptogams

increases and vascular plants become scattered. In our

material, the vegetation of the latest snow beds represents

the Ant he lia juratzkana-P olytric hastrum sexang ulare type

corresponding to the snowbed communities without a

field layer of Gjrerevoll ( 1 956).

Overall, the series on siliceous substrates corresponds

to the pattern introduced from subcontinental mountains

of northern Fennoscandia (Oksanen & Virtanen 1 995).

This study suggests that on level plateaux and in wide

depressions there are communities that are not members

in the mesoscale topographic ridge-depression series. The series on siliceous substrate is distinctly different from

any of the community series of Spitsbergen.

(2) The series on calcareous substrate. This parallel series

of communities along a ridge-depression transition can be

abstracted. The series lies in the middle of the second

gradient of the DCA ordination (Fig. 5, 1 9b). The ridges

are occupied by heaths of the Dryas octopetala-Carex

rupestris type which shows a transition to chionophilous

communities of the Cassiope tetragona-Dryas octopetala

type. The ridge communities and weakly chionophilous

heaths are relatively similar to vegetation encountered in

the corresponding sites of Spitsbergen. These heaths of

northwestern Fennoscandia thus represent a link to

circumpolar arctic vegetation (Gjrerevoll 1 954; Bocher

1 963 ; R�nning 1 965 ; Eurola 1 974). The Salix polaris

Silene acaulis type represents early snowbeds, and the

latest snowbeds are occupied by the vegetation of the

Saxifraga oppositifolia-Ranunculus sulphureus type. Over

all, this series is similar to the one described by Gjrerevoll

( 1 956:33) from Swedish Tome Lappmark. In the latest

snowbeds on calcareous substrates, communities domi

nated by Distichium capillaceum have been found by

Gjrerevoll ( 1 956), but such communities were not en

countered by us. The peculiar Koenigia-Phippsia com

munity is found close to melting snow-fields maintaining

continuous irrigation (Pililsson 1 994: fig . 1 :9) . The

chionophilous-snowbed communities of northern Fenno

scandia have little in common with corresponding com

munity types on Spitsbergen. Fennoscandian snowbeds

show at least physiognomic resemblance to the corre

sponding communities on Alaskan mountains (Gjrerevoll

1 980), although in Alaska the mosses appear to be rela

tively abundant as compared to hepatics (AI pert & Oechel

1 982).

A third series, encountered only on the slopes of Mt.

Saana, is clearly different from the two major ones : the

community series of the Festuca ovina-Potentilla crantzii

heaths appears in the lower part of the ordination space

(Fig. 5, 1 9c). The series is characteristic of sites with

moderately calcareous substrates on slopes with rela

tively favourable climate. On the ridges, we encounter a F estuca ovina and Dryas octopetala dominated community


that shows affinity with the Dryas octopetala-Carex

rupestris type. At the chionophilous sites, communities

belonging to the Festuca ovina-Potentilla crantzii type

are prevalent. These communities show a transition to the

early-melting snowbeds characterized as the Festuca

ovina-Saussurea alpina-Sanionia snowbed communities .

The relatively late snowbed sites harbour a vegetation of

the Trisetum spicatum-Sanionia type, also a member in

the suboceanic series of communities of Oksanen & Virtanen ( 1 995).

4.2 Spitsbergen

As in northwestern Fennoscandia, the community series

of Spitsbergen, can be abstracted along the ridge-depres

sion transitions . The gradient analysis (Fig. 1 4) suggests

that the communities of Spitsbergen do not fall into dis

tinct edaphic series, as is the case in northern Fennoscandia.

Instead, the series can be idealized for each climatically different subareas. Consequently, we distinguish three

series (Fig. 20) : ( 1 ) the inner fjord region; (2) the west

southwestern coast region; and (3) the Dryas region.

In the inner fjord region, two types of ridge heaths

prevail (Fig. 20a): ridges with often active patterned ground

are occupied by relatively open communities, character

ized by Saxifraga oppositifolia (the Saxifraga oppositifolia

Hypnum revolutum community). This vegetation extends

to mountain slopes up to the limits of more or less continu

ous plant cover (Virtanen et al . 1 997b). Corresponding

communities are reported also from the Ny Alesund area

(Brossard et al. 1 984) and from the Dryas region (this

study). The Saxifraga oppositifolia-Hypnum revolutum

community is relatively broad and contains sample plots

approaching the Potentilla pulchella community, so far

only anecdotally described (Elvebakk 1 994). On slightly

less extreme ridges with largely stable substrates, the

Dryas octopetala-Carex rupestris community prevails

(Virtanen et al. 1 997b). This community is also reported

from the Ny Alesund area (R�nning 1 965 ; Brossard et al .

1 984 ). On ridges in areas between the inner fjord region

and the western coast, the Luzula confusa-Gymnomitrion

community is encountered.

The most outspoken chionophobous communities de

scribed above show a transition to Dryas octopetala-Salix

polaris communities. The Cassiope tetragona heaths did

not form any distinct community clusters in our numerical

classification. These communities are, however, rather

regularly encountered in the inner fjord region (see also

Eurola 1 968; Virtanen et al . 1 997b) . Into the direction of

increasing snow cover, C. tetragona abruptly vanishes,

probably due to a too short snow-free period and/or too

shallow active layers (cf. Nams & Freedman 1 987). In the

depression sites, the abundance of vascular plants further

diminishes and the communities become heavily domi-

a)

Gymnomitrion type (on plateaux) Empetrum-Cassiope tetragona-Aiectoria t . (on smaller ridges)

Ridge

b)

Empetrum-Fiavocetraria nivalis t.

Juncus trifidus-Cassiope tetragona t

Salix herbacea-Kiaeria t.

Anthelia juratzkana-Poly-.

trum sexangulare t Depression

Dryas octopetala-carex rupestris type

c)

Festuca ovina-Dryas octopetala community

Fig. 1 9a-c. Generalized community series along ridge-depression topographic sequences in the middle oroarctic zone of northwestern Fennoscandia: a) siliceous substrate, b) calcareous substrate, c) eutrophic (slightly calcareous) substrate.

nated by mosses. The Dryas octopetala-Tomentypnum

community occupies sites of moderately late-lying snow

while the Dryas octopetala-Sanionia community occurs

on late-lying snow beds. The latest snowbeds of the inner

fjord region are poorly represented in our material. Some

of them are assigned to the Racomitrium canescens-Oxyria

community and some to the Sanionia-Poa alpigena

snow bed community, chiefly encountered in the Dryas

region. These moss-dominated communities occur more

sporadically in the inner fjord region (Eurola 1 968) where

frost churning often breaks the moss carpet and also

reindeer trampling may have similar effects . In wet de

pressions, snowbed communities with hydrophilous

mosses, e.g. Scorpidium revolvens, are found. These com

munities are often characterized by Dupontia .fisheri and

Eriophorum scheuchzeri.

On the west-southwestern coast of Spitsbergen (Fig .

20b ), a somewhat different series of communities is

found. A community with relatively abundant Raco-



mitrium lanuginosum, the Luzula confusa-Racomitrium

lanuginosum community, is characteristic for stable

ridges, whereas on unstable substrates the moss carpet i s

fragmented (the Luzula confusa-Gymnomitrion commu

nity, Eurola 1 968). These vegetation types grade to

lichen and moss-rich Luzula confusa-Sanionia commu

nities, while depression sites harbour the Sanionia

snowbed communities (Kuc 1 963 ; Eurola 1 968) . This

series is characteristic of southwestern Spitsbergen, but

Luzula confusa-Gymnomitrion community is widespread

and extends to Dryas region, where this type of vegeta

tion shows a transition to polar deserts. In the Ny Alesund

area, the northern part of the west coast, the typical

community series resembles more that of the inner fjord

region and the Dryas region. As shown by R�nning

( 1 969) and Brossard et al. ( 1 984), ridge communities are

characterized by Carex rupestris and Dryas octopetala ,

which show a transition to a community with tufts of

Deschampsia alpina and a cryptogam layer with dark

bryophytes .

a)

Sadfraga oppositifolia-Hyprum revolutum commt.rity

(Dryas octopetaa-CEI'ex rupestris c.) Ridge

Dryas octopetaa-Salix pdaris c.

b) Depression

Luzula coofusa-Gymnomitrion coraiUoides community

Luzula coofusa-Racomitrium laruginosum c.

Luzula coofusa-SGiliooia c.

c)

Papaver d81�arum pdEI' desert

------ Papaver d81Narum-Racomitrium panschii community

(Dryas octopetala-Tomertypm1n c.)

Auacan nium turgidllll-Hylocomium c.

SGiliona-SaiCifraga t?,tperborea c.

Fig. 20a-c. Generalized community series along ridge-depression topographic sequences on Spitsbergen: a) the inner fjord region, b) the west-southwestern coast region, c) the Dryas region.


In the Dryas region (Fig. 20c) (Summerhayes & Elton

1 928; Eurola 1 968) which largely corresponds to the north

ern arctic tundra zone (Elvebakk 1 985), the exposed ridges

are characterized by the Papaver dahlianum polar deserts

and associated less extreme Papaver dahlianum-Raco

mitrium panschii communities. With increasing snow depth

these show a transition to communities of the Dryas

octopetala group, of which the Dryas octopetala

Tomentypnum community from inner fjord region is also

found. These are accompanied by moss tundra communi

ties (theAulacomnium turgidum-Alopecurus borealis com

munity, the Aulacomnium turgidum-Hylocomium commu

nity and the Sanionia-Saxifraga hyperborea community)

which correspond to the Luzulion arcticae vegetation

(Elvebakk 1 985). The depressions are occupied by the

Sanionia-Poa alpigena snowbed communities. Similar com

munities as in our material from the Dryas region are

reported from SE Spitsbergen, e.g. on Barents Island

(Hofmann 1 968) and in northernmost Spitsbergen (Rein

deer Peninsula, Dahle 1 983).

5 V egetational differentiation in relation to edaphic factors

In northwestern Fennoscandia, a division into types on

calcareous soils and oligotrophic types on calcium-poor

soils seems to be clear along the topographic ridge-de

pression gradients. This conforms to earlier studies from

other mountains of Fennoscandia (e.g. Nordhagen 1 928;

1 943; Kalliola 1 939; Gjrerevol1 1 956), or the Alps (Gigon

1 97 1 ) and Alaska (Cooper 1 986) . Although the podzol

profile is weakly-developed in the middle oroarctic zone,

leaching is probably a process contributing to the distinct

division into siliceous and calcareous soils. Precipitation

is high; there is no permafrost layer counteracting water

percolation, and the plant cover includes edificator plants,

e .g . Betula nana, Cassiope tetragona, and Empetrum

nigrum ssp. hermaphroditum. On siliceous soil parent

material, these acidophilous plants may decrease base

exchange capacity and base saturation in the soil, and

exudate compounds promoting soil acidification (e.g.

Lundegardh 1 957; Miles 1 987). On the contrary, on cal

careous bedrock, supply of cations is continuous enough

to maintain base status and pH values close to the soil

surface. Although the edaphic gradient is mostly distinct,

there are circumstances where this distinctness becomes

weak or disappears.

( 1 ) The species composition of the Carex bigelowii-Salix

polaris type includes about equal ly both acidophilous

( Cassiope hypnoides, Luzula arcuata ssp. confusa, Salix

herbacea) and calciphilous plants (e.g. Salix polaris and

Silene acaulis) and it seems to represent intermediate

vegetation between acidophilous and calciphilous ones. It

may be that the chemical properties of the underlying soil

are intermediate, as a consequence of weak leaching.

Furthermore, melt water may provide an extra cation

addition and wash the humic acids off. One more factor

that may contribute to coexistence of edaphically differ

entiated species is reindeer grazing. Grazing can decimate

the cover of ericaceous dwarf shrubs and robust lichens

( Cladina arbuscula ssp. mitis and/or C. stellaris) (see also

Manseau et al . 1 996). Consequently, space is created for

calciphilous species that are normally excluded through

competition.

(2) On polygonal sites where soils of polygon centres

have higher concentrations of extractable plant nutrients

and higher pH values than in the surrounding stable ground

on otherwise siliceous substrates (Rintanen 1 970; Jonasson

& Skold 1 983; Jonasson 1 986). These polygonal soils

may thus provide substrate for plants growing normally

on calcareous soils. One example is the occurrence of

Dryas octopetala in heaths of the Gymnomitrion type.

Northern Fennoscandia differs from Spitsbergen in

that on Spitsbergen the whole range of communities in

cludes species that can be regarded as calciphilous in

northern Fennoscandia. Communities with solely

acidophilous species seem to be missing in our material

from Spitsbergen, and the floristic element confined to

acidic soils is rare on Spitsbergen (cf. Table 2). This

probably reflects presence of base-rich bedrock on

Spitsbergen, but some other factors, such as omnipres

ence of permafrost, a high frequency of cryoperturbation

as well as low precipitation, counteract leaching and

prevents formation of as acidic soils as on mountains of

northern Fennoscandia.

On Spitsbergen, plants possess edaphic preferences

(Elvebakk 1 982), but the relationship between climatic

conditions, soil and vegetation have not been much dis

cussed. The present analysis provides some evidence that

the relationship may vary depending on the geographic

scale. In the inner fjord region of Spitsbergen, the valleys

receive little precipitation (Hisdal 1 976). The precipitation

per evaporation ratio is low, and even arid conditions can

prevail. Under such conditions, soils especially on well

drained ridges are amphipercolative, and the upper soil tend

to become enriched by calcium carbonate and the soil will

become basic. This is supported by the soil analyses of

Federoff ( 1 966). On such ridges, the edaphic tolerances of

many common species may be exceeded, and instead a

rather specialized group of exacting calcitrophic species

can be found regularly (e.g. Potentilla pulchella). Similar

edaphic processes prevail also on the continental Rocky

Mountains (Bamberg & Major 1 968). More closed vegeta

tion prevail in the surroundings of the exposed ridges. The

soils are also more acidic (Federoff 1 966) especially

Cassiope tetragona and Hylocomium (Rszsnning 1 965 ;

Federoff 1 966). It is possible that acidification takes place.

Consequently, edaphic differentiation of vegetation exist in

the inner fjord region, but the differences may also reflect

an impact of vegetation on the soil and not only differences

in soil parent material.

In a regional scale, climatic factors can play a signifi

cant role. The vegetational series from the coastal region

(Fig. 20b) indicates the relatively acidophilous nature of

vegetation (the Luzula confusa-Racomitrum lanuginosum

community, for example), although soil substrates in

clude calcareous ones. Nevertheless, indicators of cal

cium carbonate tend to be infrequent. One reason may be,

that the precipitation is relatively high, promoting leach

ing of polyvalent cations from upper soil layer. Moreover,



the moist climate favours acidophilous moss, Racomitrium

lanuginosum and such lichens as Cetrariella delisei and

Cladina arbuscula ssp. mitis. It can be supposed that R.

lanuginosum functions to some extent l ike Sphagnum

causing considerable changes in their local environment

by absorbing available cations. Its ability to form exten

sive moss carpets is also a property that can be regarded as

a competitive mechanism that may result in the exclusion

of other mosses and vascular plants. In short, the observed

(at least weakly) acidophilous nature of vegetation on the

southwest-west coastal area of Spitsbergen results from

climatic reasons directly promoting soil leaching and

indirectly favouring acidophilous plants.

The third pattern in vegetation-soil relationships re

flects the cooling down of climate from favourable areas

a)

towards polar deserts. Along this gradient, cryoperturbation

can be expected to become more intense and the active

soil layer to become thinner (cf. SHiblein 1 97 1 ) . Moreo

ver, precipitation decreases. These factors counteract leach

ing. Plant cover is sparse and the nutrient demands can be

supposed to be more or less saturated. Cation exchange of

plants is slow and it hardly leads to excess of H+ ions and

soils do not become acidic . Therefore, it can be expected

that in the climatically colder areas soil parent material

plays a less significant role for plants, and the plants most

frequent on the cold areas can be regarded as circumneutral

(Sumrnerhayes & Elton 1 928 ; Eurola 1 968, 1 974). This is

also reflected in our data: the species composition in the

Dryas region gives impression of a higher proportion of

calciphilous or neutrophilous mosses and vascular plants.

c:::J Vascular plants

1 00

'# 80 (].) C) CO

� 0 u (].) > � 05 er:

60

40

20

1 00

0 � 80 Q) O'l CO

� 0 u Q) -� (i5 05 er:

60

40

20

GymnT ECtAT JtCtT ShKiT APsT

b)

OocCrT OocCtT SpSacT SoppRsT

c)

FovOocC FovPcrT FovSalpSaC TsSaT


� Robust mosses � Other bryophytes fl'll!l Lichens + black crust

Fig. 2 1 a-c. Relative coverages (%) of vascular plants, robust mosses, other bryophytes and lichens in generalized community series along ridge-depression topographic sequences in the middle oroarctic zone of northwestern Fennoscandia: (a) silicaceous substrate; (b) calcareous substrate; (c) eutrophic (slightly calcareous) substrate. See text for further explanation.

6 Abundance patterns of bryophytes in

topographic and regional gradients

In terms of general vegetation composition the chiono

phobous and weakly chionophilous heath vegetation of

the middle oroarctic zone in northern Fennoscandia is

composed of communities in which the ericaceous and

graminaceous plants are the two major groups of vascu

lar plants. The cryptogam layer is characterized by a

large number of bryophytes and lichens (App. 2 and 3) .

These heaths show a transition to the upper oroarctic

vegetation consisting of relatively open Luzula arcuata

ssp. confusa and Ranunculus glacialis communities (Du

Rietz 1 925 ; Oksanen & Ranta 1 992; Oksanen & Virtanen

1 995) . Communities of ridge and snowbed sites of the

middle oroarctic zone are rich in prostrate plants, small

mosses and hepatics (App. 4). The most extreme

snowbeds are characterized mainly by small mosses and

hepatics (e .g. the Anthelia juratzkana-Polytrichastrum

sexangulare type, App. 5) .

In the inner fjord region of Spitsbergen, sparsely snow

covered ridges are replaced by communities rich in grasses

and prostrate plants (the Dryas octopetala-Carex rupestris

and open Saxifraga oppositifolia-Hypnum revolutum com

munities). Dwat-f shrub communities, i .e . heaths rich iil

Cassiope tetragona are confined to narrow zones on shel

tered slopes. Lower parts of hill slopes and depressions

are occupied by the moss-rich tundra communities (e.g.

the Dryas octopetala-Tomentypnum community, App. 9).

In the west-southwestern coastal area, dwarf shrub heaths

are missing and moss and lichen-rich communities pre

vail on wind-swept and depression sites. In the Dryas

region, a large proportion of the landscape is sparsely

vegetated and ridge heaths approach polar desert vegeta

tion with scattered Papaver dahlianum (App. 8) On shel

tered sites the moss-rich communities of the Dryas

octopetala group cover a larger proportion of the terrain

and moss tundra communities become prevalent (App.

1 0) . Both in the coastal and Dryas region, and locally in

the inner fjord region, the snowbed sites are occupied by

mosses forming thick carpets, such as Sanionia (A pp. 1 1 ).

The distribution pattern of communities outlined above

suggests that the plant composition of chionophilous and

snowbed communities differ distinctly between northern

Fennoscandia and Spitsbergen. One of the main differ

ences concerns the abundance of bryophytes. This is

shown in the Figs. 14 and 1 5 where relative abundances

of:

( 1 ) robust mosses, building thick carpets by means of

vegetative growth, are loosely attached to the ground and

are susceptible to trampling or other physical disturbance

(Aulacomnium, Brachythecium turgidum, Cirriphyllum,

Hylocomium, Orthothecium chryseum, Pleurozium, Raco

mitrium, Rhytidium, Sanionia, Sphagnum and Tomen

typnum spp.) .

(2) al l other bryophytes that are different in these

characters (hepatics, e.g. Anastrophyllum, Gymnomitrion,

Lophozia spp. and small mosses, e.g. Dicranum, Disti

chium, Tortula spp.) . It seems that in northern Fenno

scandia, most of the communities are dominated by

vascular plants and by other bryophytes (the second

group above) and lichens (Fig. 2 1 ) . In contrast, on

Spitsbergen (Fig. 22), robust mosses consistently domi

nate chionophilous and snow bed sites. Furthermore, moss

dominance increases towards depression sites and from

the inner fjord region towards the coastal and Dryas

region (Fig. 22).

It has been suggested that reduced competition by

vascular plants is one of the causes for the moss abun

dance in the middle-northern arctic areas (Tallis 1 958 ;

Vitt & Pakarinen 1 977). Indeed, i t is possible that abiotic

conditions are favourable to mosses rather than to vascu

lar plants in these areas. Soils are more unstable due to

solifluction and cryoturbulence, thus roots of vascular

plants are broken, and low temperatures due to permafrost

reduce root development (Bell & Bliss 1 978). Permafrost

impedes drainage and maintains a high concentration of

mineral elements in the soil, which in turn may favour

mosses. However, a copious moss vegetation is found in

the uplands of the Faeroe Islands and Iceland where there

is no permafrost (Bocher 1 937; Bjamason 1 99 1 ) . 1t can be

readily noticed that these areas are more oceanic and

receive high precipitation which contributes to abundant

moss vegetation (Du Rietz 1 925). However, a copious

moss vegetation is not only confined to areas with high

precipitation, as such vegetation is also found in continen

tal parts of the circumpolar high arctic with remarkably

low precipitation (Vitt & Pakarinen 1 977; Sumina 1 986).

As the mountains of northern Fennoscandia receive an

amount of precipitation which is comparable to oceanic

areas (Waiter & Lieth 1 975) and the mountains are often

covered by clouds which provide further irrigation in the

form of fog, it is surprising that no similar copious moss

communities are commonly found. Actually, such veg

etation is not totally missing from Fennoscandia. In the

upper oroarctic habitats, patches of thick moss carpets

occur as isolated oases in sterile boulder fields (e.g. on the

upper slope of Skuvgilrassa in interior Finnmark, Oksanen

& Virtanen 1 99 5 ) and at the highest altitudes on



Fennoscandian mountains (Vestergren 1 902; Du Rietz

1 925). Consequently, mere physical constraints do not

seem to provide a sufficient explanation for the absence of

moss banks below the altitudinal limit of continuous

vegetation in northwestern Fennoscandia. It has been

suggested that one cause for that is the Norwegian lem

ming (Oksanen 1 988; Lundberg et al . manuscr. ) . The

Norwegian lemming is able to deplete the moss vegeta

tion quite efficiently from snowbed habitats (e.g. Kalela

1 96 1 ; Moen et al . 1 993). Depletion of moss vegetation

1 00

� 80

a; 60 > 0 (,) � 40 � � 20

1 00

80

a; 60 > 0 (,)

-� 40 -ro � 20

a)

Sopp-irC b)

LcRIC

c)

P�pC


OocSpC Doe SaC

Le SaC SaC

AtHC SaPalpC

creates space for small hepatics and mosses and prostrate

vascular plants . A reverse change in vegetation cover has

taken place as a consequence of experimental exclusion

of grazing on a snowbed (Virtanen et al . 1 997a; see also

Batzli et al . 1 980): the plant cover has shown signs of

succession towards moss dominance as in communities

encountered on lemming-free arctic islands (Virtanen et

al . 1 997b) . Thus, existence of copious moss vegetation in

conditions comparable to middle ( oro )arctic zones may

also depend on the absence of moss-eating lemmings.

c::J Vascular plants FrA Robust mosses FrA Other bryophytes FrA Lichens + black crust

Fig. 22a-c. Relative cover (%) of vascular plants, robust mosses, other bryophytes and lichens in generalized community series along ridge-depression topographic sequences on Spitsbergen: a) inner fjord region; b) coastal region; c) Dryas region. See text for further explanation.

7 Acknowledgements

We thank A. Hakala for help with the field work on Spitsbergen and L. Oksanen for reading an earlier version of the

manuscript. We also thank A. Elvebakk and an anonymous referee for comments. The study was fmancially supported by

the Research Council for Environment and Natural Resources of Finland and the University of Oulu.

8 References

Acock, A.M. 1 940. Vegetation of a calcareous inner fjord region in Spitsbergen. - J. Ecol . 28: 8 1 - 1 06.

Ahti, T., Hamet-Ahti, L. & Jalas, J . 1 968. Vegetation zones and their sections in northwestern Europe. - Ann. Bot. Fenn. 5 : 1 69-2 1 1 .

Aleksandrova, V .D. 1 988. Vegetation of the Soviet polar deserts. - Cambridge University Press, Cambridge.

Alendal, E. & Byrkjedal, I . 1 976. Population size and reproduction of the reindeer (Rangifer tarandus platyrhynchus) on Nordenskioldland, Svalbard. - Nor. Polarinst. Arbok 1 974: 1 39- 1 52.

Alpert, P. & Oechel, W.C. 1 982. Bryophyte vegetation and ecology along a topographic gradient in montane tundra in Alaska. - Hol . Ecol . 5: 99- 1 08.

Andreev, M. , Kotlov, Y. & Makarova, I . 1 996. Checklist of lichens and l ichenicolous fungi of the Russian Arctic. -Bryologist 99: 1 37- 1 69.

Bamberg, S .A. & Major, J . 1 968. Ecology of the vegetation and soils associated with calcareous parent materials in three alpine regions of Montana. - Ecol. Monogr. 38 : 1 27- 1 67.

Batten, D.S. & Svoboda, J . 1 994. Plant communities on the uplands in the vicinity of the Alexandra Fiord Lowland. In: Svoboda, J. & Freedman, B. (eds .) Ecology of a polar oasis: Alexandra Fiord, Ellesmere Island, Canada. Captus University Publ . , Toronto, pp. 97- 1 10.

Batzli, G.O., White, R.G., MacLean, S.F. , Jr. , Pitelka, F.A. & Collier, B .D. 1 980. The herbivore-based trophic system. In: Brown, J . , Miller, P.C., Tieszen, L.L. & Bunnell , F.L. (eds. ) An arctic ecosystem. The coastal tundra at Barrow, Alaska. Hutchinson & Ross Inc. , Stroudsberg, Dowden, pp. 335-4 1 0.

Bell, K.L. & B liss, L.C. 1 978. Root growth in a polar sernidesert environment. - Can. J. Bot. 56: 2470-2490.

Bjamason, A.H. 1 99 1 . Vegetation on lava fields in the Hekla area, Iceland. - Acta Phytogeogr. Suec. 77. Uppsala.

B l iss, L.C. , Henry, G.H.R. , Svoboda, J . & B liss, D.I . 1 994. Patterns of plant distribution within two polar desert landscapes. - Arct. Alp. Res. 26: 46-55.

B l iss, L.C. , Svoboda, J . & Bl iss, D.I . 1 984. Polar deserts, their plant cover and plant production in the Canadian High Arctic. - Hol. Ecol . 7 : 305-324.

Bocher, T.W. 1 933. Studies on the vegetation of the east coast of Greenland. - Medd. Gr�nl. 1 04,4: 1 -56.

Bocher, T.W. 1 937. Nogle Studier over Frer�ernes alpine Vegetation. - Bot. Tidskr. 44: 1 54-20 1 .

Bocher, T.W. 1 954. Oceanic and continental vegetation complexes in southwest Greenland. - Medd. Gr�nl. 1 48, 1 : 1 -336.

Bocher, T.W. 1 963. Phytogeography of Middle West Greenland. - Medd. Gr�nl. 1 48,3 : 1 -289.

Brattbakk, I . 1 983. Lavrik morenevegetasjon pa Br�ggerhalv�ya, Svalbard. - Kungl. Nor. Vidensk. Sellsk. Mus., Rapp. Bot. Ser. 1 983(7): 1 1 - 1 6.

Braun-Blanquet, J. 1 926. Vegetations-Entwicklung und Bodenbildung in der alpinen Stufe der Zentral-Alpen (in collaboration with Hans Jenny). - Denkschr. Schw. Naturf. Ges. B 58 Part 2: 1 83-349.

Bringer, K. -G. 1 96 1 . Den lagalpina Dryas-hedens differentiering och standortsekologi inom Tornetrask -ornradet. 1-II. - Sven. Bot. Tidskr. 55: 349-375, 55 1 -584.

Brossard, T., Deruelle, S . , Nirnis, P.L. & Petit, P. 1 984. An interdisciplinary approach to vegetation mapping on lichendominated systems in high-arctic environment, Ny Alesund (Svalbard). - Phytocoenologia 1 2 : 433-453.

Cal laghan, T.V. & Emanuelsson, U. 1 985. Population structure and processes of tundra plants and vegetation. - In: White, J . (ed.) The population structure of vegetation. Dr. W. Junk Publ . , Dordrecht, pp. 399-439.

Cooper, D.J. 1 986. Arctic-alpine tundra vegetation of the Arrigetch Creek V alley, Brooks Range, Alaska. - Phytocoenologia 14 : 467-555.

Dahl, E. 1 957. Mountain vegetation in South Norway and its relation to the environment. - Skr. Nor. Vidensk. Akad. Oslo. I . Mat.-Naturvidensk. kl. 1 956(3) : 1 -374.

Dahl, E. 1 987. Alpine-subalpine plant communities of South Scandinavia. - Phytocoenologia 1 5 : 455-484.

Dahle, 0. 1 983. Sn�leiepreget vegetasjon pa Reinsdyrflya, Svalbard. - Kungl. Nor. Vidensk. Sellsk. Mus., Rapp. Bot. Ser. 1 983(7): 1 7-32.

Daniels, F.J .A. 1 982. Vegetation of the Angmagssalik District, Southeast Greenland. IV. Shrub, dwarf shrub and terricolous l ichens. - Medd. Gr�nl. B iosci. 1 0: 1 -78.



Daniels, F.J.A. 1 994. Vegetation classification in Greenland. J. Veg. Sci. 5: 78 1 -790.

de Molenaar, J .G. 1 976. Vegetation of the Angmagssalik District, Southeast Greenland II. Herb and snow-bed vegetation. - Medd. Grj�jnl. 1 98,2: 1 -265 .

DierBen, K. 1 992. Zur Synsystematik nordeuropaischer V egetationstypen. 1 . Alpine Vegetation und floristisch verwandte Vegetationseinheiten tieferer Lagen sowie der Arktis. -Ber. Reinhold-Ttixen-Ges. 4: 1 9 1 -226.

Dingman, S.L. , Barry, R.G., Weller, G., Benson, C., LeDrew, E.F. & Goodwin, C.W. 1 980. C limate, snow cover, microclimate, and hydrology. - In: Brown, J . , Miller, P.C. , Tieszen, L.L. & Bunnell, F.L. (eds.) An Arctic ecosystem. The coastal tundra at Barrow, Alaska. Hutchinson and Ross Inc. , Stroudsberg, Dowden, pp. 30-65 .

Dubiel, E. & Olech, M. 1 990. Plant communities of NW Sorkapp Land (Spitsbergen). - Zeszyty Naukowe Uniwersytetu Jagiellonskiego, Prace Botaniczce 2 1 : 35-74.

Du Rietz, G.E. 1 925 . Die regionale Gliederung der skandinavischen Vegetation. - Sv. Vaxtsoc. Sa.J.lsk. Handl. 8: 1 -60.

Elvebakk, A. 1 982. Geological preferences among Svalbard plants. - Inter-Nord 1 6 : 1 1 -30.

Elvebakk, A. 1 985. Higher phytosociological syntaxa on Svalbard and their use in subdivision of the Arctic. - Nord. J. Bot. 5 : 273-284.

Elvebakk, A. 1 994. A survey of plant associations and alliances from Svalbard. - J. Veg. Sci. 5: 79 1 -802.

Eurola, S . 1 968. Ober die Fjeldheidevegetation in den Gebieten von Isfjorden und Hornsund in Westspitsbergen. - Aquilo Ser. Bot. 7 : 1 -56.

Eurola, S . 1 97 1 . The middle arctic mire vegetation in Spitsbergen. - Acta Agr. Fenn. 1 23: 87- 1 07 .

Eurola, S . 1 974. The plant ecology of northern Kiolen, arctic or alpine? - Aquilo Ser. Bot. 1 3 : 1 0-22.

Federoff, N. 1 966. Les sols du Spitsberg accidental, X. -Spitsberg 1 964: 1 1 1 -228.

Fries, T.C.E. 1 9 1 3 . Botanische Untersuchungen im nordlichsten Schweden: ein Beitrag zur Kenntnis der alpinen und subalpinen Vegetation in Tome Lappmark. - Vetensk. Prakt. Unders. Lappl. anordn. Luossav.-Kiirunav. AB, Alrnquist & Wiksells, Uppsala.

Gigon, A. 1 97 1 . Vergleich alpiner Rasen auf Silikat- und auf Karbonatboden. - V eroff. Geobot. Inst. ETH, Stift. Rtibel 48: 1 - 1 59.

Gjrerevoll , 0. 1 954. Kobresieto-Dryadion in Alaska. - Nytt Mag. Bot. 3 : 5 1 -54.

Gjrerevoll, 0. 1 956. The plant communities of the Scandinavian alpine snowbeds. - K. Nor. Vidensk. Selsk. Skr. 1 956( 1 ) : 1 -405 .

Gjrerevoll , 0. 1 980. A comparison between the alpine plant communities of Alaska and Scandinavia. - Acta Phytogeogr. Suec. 68: 83-88.

Haapasaari, M. 1 988. The oligotrophic heath vegetation of northern Fennoscandia and its zonation. - Acta Bot. Fenn. 1 35 : 1 -2 1 9 + App. : Tables 1 -23.

Hadac, E. 1 946. The plant communities of Sassen Quarter, Vestspitsbergen. - Stud. Bot. Cech. 7: 1 27- 1 64.

Hadac, E. 1 989. Notes on plant communities of Spitsbergen. Folia Geobot. Phytotaxon. 24: 1 3 1 - 1 69.


Hamet-Ahti, L. 1 963 . Zonation of the mountain birch forests in northernmost Fennoscandia. - Ann. Bot. Soc. V anamo 34: 1 - 1 27.

Hartmann, H. 1 980. Beitrag zur Kenntnis der Pflanzengesellschaften Spitsbergens. - Phytocoenologia 8 : 65- 147.

Hedberg, 0., Martensson, 0. & Rudberg, S . 1 952. Botanical investigations in the Pa.J.tsa region of northernmost Sweden. - Bot. Not . (supplement) 3(2): 1 -209.

Henttonen, H., Kaikusalo, A. , Tast, J. & Viitala, J . 1 977. Interspecific competition between small rodents in subarctic and boreal ecosystems. - Oikos 29: 58 1 -590.

Hill, M.O. 1 979. TWINSPAN - A FORTRAN programme for arranging rnultivariate data in an ordered two-way table by classification of individuals and attributes. - Cornell University, lthaca.

Hill , M.O. & Gauch, H.G. 1 980. Detrended correspondence analysis: improved ordination technique. - Vegetatio 42: 47-58.

Hiltunen, R. 1 980. Temperature and snow conditions on snowbeds and wind-exposed places on Pikku-Malla, NW Finnish Lapland ( in Finnish). - Luonnon Tutkija 84: 1 1 -14.

Hisdal , V. 1 976. Geography of Svalbard. Polarhandbok Nr. 2 . - Norsk Polarinstitutt, Oslo.

Hofmann, W. 1 968. Geobotanische Untersuchungen in StidostSpitsbergen 1 960. - Erg. Stauferland-Expedition 1 959/ 1 960 8: 1 -83.

Jarvinen, A. 1 987. Basic climatological data on the Kilpisjarvi area, NW Finnish Lapland. - Kilpisjarvi Notes 1 0: 1 - 1 6 .

Jonasson, S. 1 986. Influence of frost heaving on soil chemistry and on the distribution of plant growth forms. - Geogr. Ann. 68A: 1 85- 1 95 .

Jonasson, S . & Skold, S .E. 1 983. 1nfluences of frost-heaving on vegetation and nutrient regime of polygon-patterned ground. - Vegetatio 53: 97- 1 1 2.

Kalela, A. 1 939. Uber Wiesen und wiesenartige Pflanzengesellschaften auf der Fisherhalbinsel in Petsamo Lappland. - Acta For. Fenn. 48 : 1 -523.

Kalela, 0. 1 96 1 . Seasonal change of habitat in the Norwegian Lemming, Lemmus lemmus (L.). - Ann. Acad. Scient. Fenn. Ser. A IV Bioi. 55 : 1 -72.

Kalliola, R . 1 939. Pflanzensoziologische Untersuchungen in der alpinen Stufe Finnisch-Lapplands. - Ann. Bot. Soc . Zool.Bot. Fenn. Vanamo 1 3 : 1 -328.

Kojola, 1 . , Aikio, P. & Helle, T. 1 993. 1nfluences of natural food resources on reindeer husbandry in northern Lapland (in Finnish). - Res. Inst. Nor. Finl . , Res. Rep. 1 1 6: 1 -39.

Kuc, M. 1 963. Flora of mosses and their distribution on the north coast of Hornsund (S.W. Svalbard). - Fragm. Flor. Geobot. 9: 29 1 -375 .

Laine, K. & Henttonen, H. 1 983. The role of plant production in microtine cycles in northern Fennoscandia. - Oikos 40: 407-4 1 8 .

Lid, J. & Lid, D.T. 1 994. Norsk Flora. 6. ed. (edited by R. Elven). - Det Norske Sarnlaget, Oslo.

Lloyd, A.H. , Armburster, W.S. & Edwards, M .E. 1 994. Ecology of a steppe tundra gradient in interior Alaska. - J. Veg. Sci . 5: 897-9 1 2.

Lundberg, P.A., Virtanen, R.J. , Oksanen, L. & Moen, J. Plant community structure on Arctic islands: absence of herbivores


favours moss dominance. Manuscript. Lundegardh, H. 1 957. Klima und Boden, 5 . Auflage. - VEB,

Gustav Fischer Verlag, Jena. Major, H. & Nagy, J . 1 972. Geology of the Adventdalen map

area. - Nor. Polarinst. Skr. 1 38 : 1 -58. Manseau, M. , Huot, J . & Crete, M. 1 996. Effects of summer

grazing by caribou on composition and productivity of vegetation: community and landscape level. - J. Ecol. 84: 503-5 1 3 .

Mehlum, F. 1 990. Birds and mammals of Svalbard. - Nor. Polarinstitutt, Polarhandbok No. 5, Oslo.

Miles, J . 1 987. Soil variation caused by plants: a mechanism of floristic change in grassland? - In: van Andel, J., Bakker, J.P. & Snaydon, R.W. (eds.) Disturbance in grasslands. Dr .W. Junk Publishers, Dordrecht, Boston, Lancaster, pp. 37-49.

Miller, N .G. & Alpert, P. 1 984. Plant associations and edaphic features of a high arctic mesotopographic setting. - Arct. Alp. Res. 1 6: 1 1 -24.

Moen, J . , Lundberg, P.A. & Oksanen, L. 1 993. Lemming grazing on snow-bed vegetation during a population peak, Northem Norway. - Arct. Alp. Res. 25 : 1 30- 1 35 .

Mook, R. & V orren, K.-D. 1 990. Temperaturklimaet ved grensen mel lom fjellvegetasjons-beltene. - Polarflokken 1 4: 55-1 07 .

Muc, M. & B liss, L.C. 1 977. Plant communities of Truelove Lowland. - In: B liss, L.C. (ed.) Truelove Lowland, Devon Island, Canada: A High Arctic Ecosystem. University of Alberta Press, Edmonton, pp. 1 43- 1 54.

Nams, M. & Freedman, B . 1 987. Ecology of heath communities dominated by Cassiope tetragona at Alexandra Fiord, Ellesmere Island, Canada. - Hol. Ecol . 1 0: 22-32.

Nimis, P.L. 1 985. Structure and floristic composition of a high arctic tundra: Ny Alesund (Svalbard Archipelago). lnterNord 17 : 47-58.

Norderhaug, M. & Reimers, E. 1 976. Reinstarnmen pa Svalbard. - Forskningsnytt 2 1 : 26-3 1 .

Nordhagen, R . 1 928. Die Vegetation und Flora des Sylenegebietes. I . Die Vegetation. - Skr. Nor. Vidensk. Akad. Oslo. I. Mat. Naturvidensk. kl . 1 927( 1 ) : I-IX + 1 -6 1 2 .

Nordhagen, R. 1 936. Versuch einer neuen Einteilung der subalpinen-alpinen Vegetation Norwegens. - Bergens M us. Arbok 1 936 Naturvidensk. rekke 7: 1 -88 .

Nordhagen, R . 1 943. Siki lsdalen og Norges fjellbeiter. En plantesosiologisk monografi. - Bergens M us. Skr. 22: I-XVI + 1 -607.

Nordhagen, R. 1 955. Kobresieto-Dryadion in northern Scandinavia. - Sven. Bot. Tidskr. 49: 63-87.

Ohlson, B. 1 964. Frostaktivitiit, Verwitterung und Bodenbildung in den Fjeldgegenden vom Enontekio, Finnisch-Lappland. - Fennia 89: 145- 1 65 .

0kland, RH. 1 990. Vegetation ecology: theory, methods and applications with reference to Fennoscandia. - Sommerfeltia (supplement) 1 : 1 -233.

Oksanen, L. 1 976. On the use of the Scandinavian type class system in cover estimation. - Ann. Bot. Fenn. 1 3 : 1 49- 1 53 .

Oksanen, L. 1 988. Ecosystem organization: mutualism and cybernetics or plain Darwinian struggle for existence? - Am. Nat. 1 3 1 : 424-444.

Oksanen, L. 1 990. Predation, herbivory and plant strategies

along gradients of primary productivity. - In: Tilman, D. & Grace, J .B . (eds .) Perspectives to plant competition, Academic Press, London, pp. 445-474.

Oksanen, L. , Oksanen, T., Ekerholm, P., Moen, J . , Lundberg, P., Schneider, M. & Aunapuu, M. 1 996. Structure and dynamics of arctic-subarctic grazing webs in relation to primary productivity. - In: Polis, G.A. & Winemiller, K. (eds .) Food webs: integration of patterns and dynamics, Chapman and Hal l , New York, pp. 23 1 -242.

Oksanen, L. & Ranta, E. 1 992. Plant strategies along vegetational gradients on the mountains of lddonjarga - a test of two theories. - J. Veg. Sci. 3: 1 75- 1 86.

Oksanen, L. & Virtanen, R. 1 995. Topographic, altitudinal and regional patterns in continental and suboceanic heath vegetation of northern Fennoscandia. - Acta Bot. Fenn. 1 53 : 1 -80.

Pahlsson, L. ( ed. ) 1 994. Vegetationstyper i Norden. -TemaNord 1 994: 665.

Phil lipi, G. 1 973. Moosflora und Moosvegetation des FreemanSund-Gebietes (Siidost-Spitzbergen). Franz Steiner Verlag GmbH, Wiesbaden.

Podani, J . 1 984. Spatial processes in the analysis of vegetation: theory and review. - Acta Bot. Hung. 30: 75- 1 1 8 .

Punsvik, T., Syvertsen, A. & Staaland, H. 1 980. Reindeer grazing in Adventdalen, Svalbard. - In: Reimers, E., Gaare, E. & Skjenneberg, S. (eds .) Proceedings of the 2nd International Reindeer/Caribou Symposium, R�ros, Norway, 1 979. Direktoratet for vilt og ferskvannsfisk, Trondheim, pp. 1 1 5-1 23 .

Rastorfer, J .R . 1 978. Composition and bryomass of the moss layers of two wet-tundra-meadow communities near Barrow, Alaska. - In: Tieszen, L.L. (ed.) Vegetation and production ecology of an A1askan Arctic tundra, Ecological Studies 29, Springer Verlag. New York-Heidelberg-Berlin, pp. 1 69- 1 83 .

Rintanen, T. 1 970. On the vegetation and ecology of frost ground sites in eastern Finnish Lap land. - Ann. Bot. Fenn. 7 : 1 -24.

R�nning, 0.1. 1 965 . Studies in Dryadion of Svalbard. - Nor. Polarinst. Skr. 1 34: 1 -52.

R�nning, 0.1. 1 969. Features of the ecology of some Arctic Svalbard (Spitsbergen) plant communities. - Arct. Alp. Res. 1 : 29-44.

Santesson, R. 1 993. The lichens and lichenicolous fungi of Sweden and Norway. - SBT-Forlaget, Lund.

Sheard, J.W. & Geale, D.W. 1 983. Vegetation studies at Polar Bear Pass, N.W.T. I . Classification of plant communities. Can. J. Bot. 6 1 : 1 6 1 8- 1 636.

Soderstrom, L. , Hedenas, L. & Hallingback, T. 1 992. Checklista over Sveriges mossor. - Myrinia 2: 1 3-56.

Soyrinki, N. 1 939. Studien iiber die generative und vegetative Vehrmehrung der Samenpflanzen in der alpinen Vegetation Petsamo-Lapplands. II. Speziel ler Teil . - Ann. Bot. Soc. 'Vanamo' 14 : 1 -404.

Stablein, G. 1 97 1 . Der polare Permafrost und die Auftauschicht in Svalbard. - Polarforschung 4 1 : 1 1 2- 1 20.

Steffensen, E. 1 982. The climate at Norwegian Arctic Stations. - Klima 5: 1 -44.

Sumina, 0.1. 1 986. A supplement to the flora and vegetation of the Kotelny Island and B unge Land (Novosiberian Islands)



(in Russian). - Botaniceski j Zumal 7 1 : 903-9 1 1 . Summerhayes, V.S. & Elton, C.S. 1 923. Contribution to the

ecology of Spitsbergen and Bear Island. - J. Ecol. 1 1 : 2 1 4-286.

Summerhayes, V.S. & Elton, C.S. 1 928. Further contributions to the ecology of Spitsbergen. - J. Ecol. 1 6: 1 93-268.

Tallis, J .H . 1 958 . Studies in the biology and ecology of Rhacomitrium lanuginosum Brid. - J. Ecol. 46: 27 1 -288.

ter Braak:, C. J . F. 1 988 . CANOCO - a FORTRAN program for canonical community ordination by partial detrended canonical correspondence analysis, principal components analysis and redundancy analysis. -Technical Report LW A-88-02: 1 -95. Ministerie van Landbouw en Visserij , Directoraat-Generaal Landbouw en Voedselvoorziening. Wageningen.

ter Braak:, C. J . F. 1 990. Update notes: CANOCO version 3 . 1 . Agricultural Mathematics Group, Wageningen.

Triloff, E.G. 1 944. Verbereitung und Okologie der Gef<isspflanzen im Gebiete des Homsundes, ein Beitrag zur Vegetationskunde Spitzbergens. - Bot. Jahrb. Syst., Pflanzengesch. Pflanzengeogr. 73: 259-360.

Uusinoka, R. 1 980. The bedrock and its influence on the land forms of the Kilpisjiirvi area, NW Finland (in Finnish). Luonnon Tutkija 84: 2-6.


Vestergren, T. 1 902. Om den olikformiga snobeUickningens inflytande pa vegetationen i Sarjekfjallen. - Bot. Not. 1 902: 24 1 -268.

Virtanen, R.J., Henttonen, H. & Laine, K. 1 997a. Lemming grazing and structure of snowbed plant community - a longterm experiment at Kilpisjiirvi, Finnish Lapland. - Oikos.

Virtanen, R.J., Lundberg, P., Moen, J. & Oksanen, L. 1 997b. Topographical and altitudinal patterns in plant communities on European arctic islands. - Polar Bioi . 1 7 : 95- 1 1 3 .

Vitt, D.H. & Pak:arinen, P. 1 977. The bryophyte vegetation, production, and organic components of Truelove Lowland. - In: Bliss, L.C. (ed.) Truelove Lowland, Devon Island, Canada: A High Arctic Ecosystem. University of Alberta Press, Edmonton, pp. 225-244.

Wahlenberg, G. 1 8 1 2 . Flora lapponica. - Berolini. Walker, M.A. , Daniels, F.J .A. & van der Maarel, E. 1 994.

Circumpolar arctic vegetation: introduction and perspectives. - J. Veg. Sci. 5 : 758-764.

Waiter, H. & Lieth, H. 1 975. Klimadiagrarnrn-Weltatlas. -Gustav Fischer Verlag, Jena.

Warming, E. 1 908. The structure and biology of arctic flowering plants. I. Ericinae. - Medd. Gronl . 34: 1 -7 1 .

Winsnes, T.S. , Heintz, A . & Heintz, N . 1 962. Aspects of the geology of Svalbard. - Nor. Polarinst. Skr. 87: 1 -34.


Appendix 1 . Mean percentage cover of plants in community types of the Festuca ovina-Potentilla crantzii group. l - Festuca ovina-Dryas octopetala community, 2 - Festuca ovina-Potentilla crantzii type, 3 - Festuca ovina-Dryas octopetala-Hylocomium community, 4 -Festuca ovina-Saussurea alpina-Sanionia community, 5 - ]uncus trifidus-Cassiope tetragona type, mossy variant. The frequencies of the taxa are indicated as follows: bold, f >66.7, underlined, 33.3<f:;66.7, normal text, f�33 .3 .

A lchemilla sp.

Antennaria alpina

Antennaria canescens

Anthoxanthum odoratum

A rabis alpina

Bartsia alpina

Bistorta vivipara

Calamagrostis lapponica

Carex bigelowii

Carex rupestris

Carex vaginata

Cassiope tetragona

Cerastium alpinum

Draba daurica

Dryas octopetala

Empetrum nigrum ssp. hermaphr.

Euphrasia frigida

Festuca ovina

Hieracium alpinum

Linnaea borealis

Luzula multiflora ssp. frigida

Luzula spicata

Oxyria digyna

Phyllodoce caerulea

Poa alpina

Potentilla crantzii

Rhodiola rosea

Salix hastata

Salix polaris

Salix reticulata

Saussurea alpina

Saxifraga cernua

Saxifraga cespitosa

Saxifraga nivalis


Selaginella selaginoides

Silene acaulis

Solidago virgaurea

Thalictrum alpinum

Trisetum spicatum

Vaccinium uliginosum

Vaccinium vitis-idaea

Viola biflora

0.9

0.3

0. 1

0. 1

0.4

0. 1

li

1 .0

2 .8

0. 1

0. 1

1 . 8

0.4

2

0.3

1 .8

0.5

4.6 0.5

1 9.7 3.9

0.9

0.4 0.3

15.4 30.0 0.3 0.5

0.3

0.3

2.3

lA 0.0

1 .8

1 .0

0. 1

lA 0.4

0.4

0.3

2.8

1 . 1

1 .9

0. 1

l.J. 2.6

1 .8

0.5

0.3

1 . 8

0.3

2.5

0.3

0.8

0.3

3.5

2.3

2.0

0.3

0.3

4.0 2.5

3

0.2

0.2

0.2

6.6

4

2.9

6.0

1 .3 2.9

4.5 1 2.0

5

0.3

2.8

3.0 0.3

6.4 0.4 0.3

0.4 0.4 15.5 0.6 1 1 .7

9.3 5.8

24.8 1 2.0 1 1 .1 0.3

1 0.3 0.4 4.4

0.2

0.4

9.3

u 0.2

2.,_Q 9.3 3 .2

0.4

0.4

0.2

1 .5

.Ll

4.7

9.1

2.9

3.4

0.4

3.8 0.3

0.3

0.6

0.3

6.7

0.3

8 .8

6.4 23.8 2.8

Additional species, occurring only in one cluster with a low frequency.

Andreaea rupestris

Bartramia ithyphylla

Dicranoweisia crispula

Dicranum fuscescens

Dicranum scoparium

Distichium capillaceum

Hylocomium splendens var. a/ask.

Mnium blyttii

Pleurozium schreberi

Pohlia cruda

Pohlia spp.

Polytrichastrum alpinum

Polytrichumjuniperinum

Rhytidium rugosum

Sanionia uncinata

Schistidium sp.

Anastrophyllum minutum

Barbilophozia floe rkei

Barbilophozia hatcheri

Gymnomitrion concinnatum

Tritomaria quinquedentata

Alectoria ochroleuca

Cetraria ericetorum

Cetraria islandica

Cladina arbuscula s p. mitis

Cladina rangiferina

Cladonia chlorophaea

Cladonia gracilis

Cladonia pocillum

Cladonia pyxidata

Cladonia uncia/is

Flavocetraria cucullata

Flavocetraria nivalis

Peltigera malacea

Stereocaulon alpinum

Thamnolia vermicularis

Total

0.3

0. 1

0. 1

0.2

0.6

0. 1

0.4

0. 1

0.3

0. 1

0.3

0.3

0. 1

l.J. 0.3

0.5

0. 1

0. 1

0.4

0. 1

0.6

1 . 1

0. 1

0. 1

0.3

2

0.3

0.3

3

0.2

u

4

0.4

5

0.9 0.3

0.8 1 1 .2 0.3

2.0 26.6 .!L2. 13.2

0.3

7.2

1 . 8

0.3

1 .3 0.3

0.5

0.3

0.3

1 .3

0.2 0.4 0.3

0.2

1 .5

0.2

0.2

0.2

0.8

0.2

0.2

1 .0 0.2

0.2

0.4

1 .3

6.8

1 .3 0.4

1 .3

0.3

0.3

0.9

2.2

0.3

2.5

0.9

0.3

5.1

0.6

0.6

0.3

0.3

0.3

0.6

0.9 0.6

0.3

0.3

0.3

90.7 1 87.0 1 80.3 1 29.9 1 34. 1

1 : Antennaria dioica ( 1 .9), Campanula rotundifolia (0.4), Deschampsiaflexuosa ( 1 .8), Geranium sylvaticum (0. 1 ), Juniperus communis (3.5), Lychnis alpina (0. 1 ),

Minuartia biflora (0. 1 ), Veronica fruticans (0.4), Abietinella abietina (0. 1 ), Bryum argenteum (0. 1 ), Lescurea saxicola (0. 1 ), Pseudoleskeella tectorum (0. 1 ),

Saelania glaucescens (0. 1 ), Tortula norvegica (0. 1 ), Preissia quadrata (0. 1 ), Ptilidium ciliare (0. 1 ), A lectoria nigricans (0.9), Bryocaulon divergens (0. 1 ),

Hypogymnia physodes (0. 1 ) , Ochrolechiafrigida (2. 1 ), Sphaerophorus globosus (0. 1 )

2 : Equisetum variegatum (0.3), Erigeron uniflorus (0.3), Solorina crocea (0.3)

3 : A rctostaphylos alpina (3 .0), Astragalus alpinus (3.0), Nephroma expallidum (0.2)

4 : Cladonia ecmocyna (0.4)

5: }uncus trifidus (2.2), Salix herbacea ( 1 7.8) , Cladina stellaris (0.3), Solorina saccata (0.3)



Appendix 2. Mean percentage cover of plants in community types of the Alectoria group. 1 - Dryas octopetala-Carex rupestris type, 2,3 - Empetrum-Cassiope tetragona-Alectoria type, 4 - Gymnomitrion type. For frequencies, see Appendix 1 .

2 3 4 2 3 4

Betula nana 4.0 6.4 Gymnomitrion concinnatum 5.5 0.7

Calamagrostis lapponica <0. 1 0.2 Gymnomitrion corallioides 0.2 2.4 22.0 Carex rupestris 5.9 Hepaticae indet. 0.2 0.5

Cassiope tetragona .LQ 22.5 .LQ 0.7 Lophozia spp. 0.5 0.7

Dryas octopetala 32.4 0.4 Ptilidium ciliare 0.2 0.7

Empetrum nigrum ssp. hermaphr. 1 . 1 8.8 7.9 Tetralophozia setiformis 0. 1 3.0 <0. 1

Festuca ovina 9.7 <0. 1 0.2

Hieracium alpinum s. !at. 0.2 A lectoria nigricans 1 .5 0.6 1.7 1 .3 Huperzia se/ago 0. 1 <0. 1 A tectoria ochroleuca 0.6 0.3 0.6 1 .3 Luzula arcuata ssp. confusa 0. 1 .LQ 0.9 Bryocaulon divergens 0.8 0.7 2.3 Luzula spicata 0. 1 Q,1 Cetraria aculeata 0. 1 Q,1 Salix herbacea 0.9 1 .4 Cetraria ericetorum 1.4 0. 1 0.6 1 .3 Salix polaris 1 .2 L8 Cetraria islandica 0.2 u Saxifraga oppositifolia OA Cetraria islandica ssp. crispiformis 0.2 0.4

Silene acaulis 0� <0. 1 Cetraria nigricans Q,1 0.3 0.5 0.5

Vaccinium vitis-idaea 1 .8 0.4 3.6 Cetrariella delisei <0. 1 Q,1 Cladina arbuscula ssp. mitis 0.5 0.6 0.5

Dicranum elongatum 0.5 2.8 Cladina rangiferina 0.2 0.5 Q,1 0.2

Die ranum fuscescens 0. 1 1 .3 li Cladina stygia 0.3 0.4

Dicranum scoparium 0.2 <0. 1 2.9 Cladonia amaurocraea <0. 1 0. 1 Q,1 Dicranum sp. 0,1 0.4 Cladonia cervicornis <0. 1 0.2

Ditrichum jlexicaule 0,1 Cladonia chlorophaea 0.2 0.7

Pogonatum dentatum 0.2 Q,1 Cladonia coccifera <0. 1 Q,1 0.3 0.9 Pogonatum urnigerum Q,1 Cladonia gracilis 0.3 0.2 1.1 Pohlia spp. 0,2 0.3 Q,1 0.7 Cladonia pocillum 0.5

Polytrichastrum alpinum 0. 1 Q,1 Cladonia uncia/is 0. 1 Q,1 0.9 Polytrichastrum sexangulare Q,1 Crustaceous black 5.5 Polytrichum hyperboreum Q,1 Crustaceous lichens 2.J. Polytrichum juniperinum <0. 1 0.6 0.5 Flavocetraria cucullata 1.0 0.3 1 .2 1 . 1 Polytrichum piliferum 0.2 0.5 2.0 Flavocetraria nivalis 3.7 1 0.0 10.3 1 .3 Polytrichum sp. 0.2 0.4 Ochrolechia frigida 2.9 3.0 8.0 5.9 Racomitrium lanuginosum 0.5 2.6 <0. 1 0.7 Pertusaria sp. 1 .3 Rhytidium rugosum O,Q Psoroma hypnorum 0. 1 0.2

Tortella fragilis 0,1 Solorina crocea Q,1 0.5

Sphaerophorus fragilis 0. 1 0 .2

Anastrophyllum minutum Q,1 0.2 0.5 Sphaerophorus globosus 1 .0 0.5 1 .5 3.4 Barbilophozia spp. 0. 1 0.7 Stereocaulon alpinum 0.3 <0. 1 0.2

Cephalozia sp. 0. 1 <0. 1 0.2 Thamnolia vermicularis 0.3 0.3 1.3 Diplophyllum taxifolium 0. 1 <0. 1 0.2

Gymnomitrion apiculatum 0.5 0.2 0.2 Total 85.6 60.5 53 .7 92.5


1 : Antennaria alpina (0.2), Carex glacialis (0.3), Cerastium alpinum (0.2), Festuca vivipara (0.2), Juniperus communis (4.4), Salix hastata ( 1 .3), Saxifraga nivalis

(0.3), Vaccinium uliginosum (0.2), Aulacomnium turgidum (0. 1 ), Bartramia ithyphylla (0.2), Cnestrum schisti (0.2), Distichium capillaceum (<0. 1 ), Encalypta

alpina (0.2), Hylocomium splendens var. alaskanum (0.2), Hypnum bambergeri (0.2), Hypnum revolutum (0. 1 ), Mnium marginatum (0.2), Plagiobryum zieri (0.2),

Plagiothecium sp. (0.2), Pleurozium schreberi (0.2), Racomitrium canescens (0.2), Saelania glaucescens (0.2), Timmia austriaca (0.2), Tortella tortuosa ( <0. 1 ), Barbilophozia hatcheri (0.2), Cladonia pyxidata (0.3), Peltigera apthosa (0.2), Solorina saccata (0.2)

2 : Pedicularis lapponica ( <0. 1 ), Phyllodoce caerulea ( <0. 1 ), Bistorta vivipara ( <0. 1 ), Pohlia nutans ( <0. 1 )

4 : A rctostaphylos alpina (0.4), Trisetum spicatum (0.2), Dicranoweisia crispula (0.4), Hypogymnia bitteri (0.7), Parmelia omphalodes (0.2), Stereocaulon sp. (0.2)



Appendix 3. Mean percentage cover of plants in community types of the ]uncus trifidus-Cassiope tetragona group. 1 ,3 - Empetrum-Cassiope tetragona type, 2 - Empetrum-Flavocetraria nivalis type, 4-8 - ]uncus trifidus-Cassiope tetragona type, 4 - Carex bigelowii variant, 5,6 - typical variants, 7 - graminoid variant, 8 - Polytrichum hyperboreum variant. For frequencies, see Appendix 1 .

2 4 6 7

Antennaria alpina . 0.2 M Antennaria canescens 0. 1 0.7

Anthoxanthum odoratum u Betula nana 2 1.7 u 0.2 0.3

Bistorta vivipara 0.4 0.4 0.6 Q2 M 0. 1

Calamagrostis lapponica 1 . 1 0.3 u M 0.3 0.3

Carex bigelowii 0.4 3.9 2.2 7.9 M 2.5 0.6 b.Q Carex vaginata 0. 1 <0. 1 0.2

Cassiope hypnoides 0.2 0.3 0.4 .LQ Cassiope tetragona 2 1 .4 7.2 1 8.2 1.4,2 0.2 0.9 <0. 1 6.6

Empetrum nigrum sp. hermaphroditum 0. 1 6.6 42.0 1 1 .7 1 . 1 0.5

Festuca ovina 3.1 0.4 0.5 L2 7.0 1 1.2 6.9 0.2

Gnaphalium supinum 0.2 Hierochloe alpina 0. 1 <0. 1 <0. 1 0.2 .LQ 0.3 <0. 1

Huperzia se/ago Q2 0.3 <0. 1

}uncus trifidus <0. 1 u lU 2 1 .3 0.3 9.8 6.0

Luzula arcuata ssp. confusa 0.3 M 1.1 M M Luzula spicata 0.4 <0. 1

Pedicularis Lapponica 0.2 0.4

Phyllodoce caerulea 0.9 1 .5 0.2 0.3 ,(U Salix herbacea 5.5 kQ .LQ L2 16.2 1 5.8 3.0 2.5

Sibbaldia procumbens 0.2 0.3 <0. 1

Solidago virgaurea 0.2 !U 0.3

Trisetum spicatum 0. 1 .u <0. 1

Vaccinium vitis-idaea 7.2 7.2 3.2 3.8 1 .9 3.1 1 . 1 1 .0

Andreaea rupestris .l.2 .LQ <0. 1 0.2 0.2 M 0.3

Aulacomnium turgidum 0. 1 Q2 Conostomum tetragonum 0.3 0.3 0.2 0.3 M <0. 1

Dicranoweisia crispula 1 . 1 0.2 0.2

Dicranum elongatum 0.2 0.3 1.1 u Dicranum juscescens 0. 1 M 0.3 1 6.5 8.9 u 0.3 <0. 1

Dicranum majus 0. 1 0.2 0.3

Dicranum scoparium 1 . 1 2.3 !1.2 1 . 1 0.5

Dicranum sp. lA 2.8 0.2 2.2 0.3

Hylocomium splendens var. alaskanum 5.9 0.2 1 .0 0.4 0. 1

Kiaeria starkei 0.9 2.8 0.3 M <0. 1

Pogonatum dentatum 1 . 1 0.2 <0. 1

Pohlia spp. !U M 0.2 0.4 M M M <0. 1

Polytrichastrum alpinum !U 1 .5 fU 4.5 <0. 1

Polytrichum commune 0.2 0.2 0.2

Polytrichum hyperboreum 0. 1 4.6

Polytrichum juniperinum !U M !!.2 0.8 kQ 4.8 <0. 1 <0. 1

Polytrichum piliferum 2. 1 3.9 <0. 1 � 0.3 5.0 0.5

Polytrichum sp. u 0.2 0.2 0.2

Racomitrium Lanuginosum 0.3 4.7 4.1 0.4 0.3 0.3

Sanionia uncinata 0.5 0.2

Anastrophyllum minutum 2.4 M 0.4 2.1 1 .3 M Anthelia juratzkana 0. 1 0.3 0.2

Barbilophozia jloerkei 0. 1 <0. 1 u <0. 1

Barbilophozia hatcheri 0.4 !U 0.3

Barbilophozia kunzeana 0. 1 0.3 0.2 0.3

Barbilophozia quadriloba 0.3 M 0.2 0.2

Barbilophozia sp. 0. 1 0.2 0.2 0.4 0.3

Blepharostoma trichophyllum 0.3 0.2 0.2 0.2 0.6 Cephalozia spp. Q2 0.2 0.9 <0. 1

Diplophyllum taxifolium 2.2 0.3 0.3

Gymnomitrion concinnatum 0.3 2.8 2.2 0. 1



App. 3, continued.

Gymnomitrion corallioides

Lophozia spp.

Ptilidium ciliare

Tritomaria quinquedentata

Alectoria nigricans

Alectoria ochroleuca

Bryocaulon divergens

Cetraria ericetorum

Cetraria islandica

Cetraria islandica ssp. crispiformis

Cetraria nigricans

Cetrariella delisei

Cladina arbuscula ssp. mitis

Cladina rangiferina

Cladina stygia

Cladonia amaurocraea

Cladonia bellidiflora

Cladonia coccifera

Cladonia crispata

Cladonia gracilis

Cladonia macrophylla

Cladonia merochlorophaea

Cladonia pyxidata

Cladonia squamosa

Cladonia subfurcata

Cladonia sulphurina

Cladonia uncialis

Flavocetraria cucullata

Flavocetraria nivalis

Melanelia hepatizon

Nephroma arcticum

Ochrolechia frigida

Pertusaria spp.

Solorina crocea

Sphaerophorus globosus


Stereocaulon paschale

Stereocaulon spp.


Total

2

0.4 .L1 (12_ 0.5 0.4

0. 1 0.3 u 0.9

0.3 0.8 <0. 1

0. 1 0.8 0.2

0.3 Q2 <0. 1

1 .6 1 .7 2. 1

0.4 <0. 1

Q2 Q2 0.9 0.2

0.4 0.4

1.9 .u 0.7

.3.,2 0.2 0.3

M 0.3

0.8 0.3 0.2

0.9 Q]_ 0.4

1 .9

2.0 1 .2 0.9

0.4 0.2

0. 1 0.2

0.3 <0. 1

0.3 0.2

0.4 0.2

0. 1

1 . 1 1.0 0.8

1 .6 1 .2 4.4

0.4 3.4 0.5

Q...2 Q2 0. 1 0.2

1 .0 .L.Q 0. 1 lA 1 . 1 1,2 0.4 1 .1 0.9

0. 1 0.3 0.4

4.5 <0. 1

0.3 Q2 0.4 Q2 0.5

1 1 3.9 1 1 9.6 1 08.7

Additional species, occurring only in one or two clusters with a low frequency.

4 6 7 8

0.2

0.4 0.9 2.2 0.3 <0. 1

.L.2 13.9 0.3

0.2 0.2 0.3

0.2 0.3 M 0.4 0.2

0.2

2.3 12.6 3. 1 M 5.2

0.2

1 .9 0.9 1.& :i,2 M 0.2 0.2

0.2 0.2 0.6 M 3.8

2.1 1 . 1 0.6 u 0.4

0.3

0.2 0.2

0.4 M <0. 1 <0. 1

0.2 (12_ <0. 1 !U 1 .0 1 . 1 1 .3 0.4 0.3

0.4 0.3

2.3 2.2 0.6 0.3 0.3

Q2 0.3

0.2 0.3 0.3

0.2 0.2 <0. 1

0.2 0.3

0.2 M 0.3 0.2

0.2 0.2 !U 0.8 1 . 1 0.9 0.4 QJ. 1 .0 0.3 0.6 0.3 <0. 1

0.4 Q2 0.3 0.7

0.4 0.2 0.6 M M 1.& 2.5

1 .3 3.9 5.3 M 25.4

0.2 0.3

0.2 0.3

0.8 0.2 0.3 <0. 1

4.7 ti 0.4 <0. 1

0.2 0.3

1 .5 0.3 <0. 1

0.8 M 0.3 !U

1 22.7 1 1 5 .3 98.4 50.6 73.9

I : Cardamine bellidifolia (0. 1 ), Dryas octopetala (0. 1 ), Festuca vi vi para (0. 1 ), Linnaea borealis ( 1 .9), Oxyria digyna (0. 1 ), Salix hastata ( 1 .9), Salix polaris (0.9), Saussurea

alpina (0.3), Saxifraga tenuis (0.3), Vaccinium myrtillus (0. 1 ), Viola biflora (0.4), Bartramia ithyphylla (0.4), Pogonatum umigerum ( 1 .8), Polytrichastrum sexangulare (0. 1 ),

Scapania sp. (0. 1 ), Sphagnum girgensohnii (7 . 1 ), Cladina stellaris ( 1 .9), Cladonia ecmocyna (0. 1 ), Cladonia pocillum (0.3), Peltigera scab rosa (0. 1 )

2 : Rubus chamaemorus (0.2), Racomitrium microcarpon (0.2), Scapania sp. (0.2), Cladoniafimbriata (0.2), Nephroma expallidum (0.2), Peltigera apthosa (0.2)

3: Dryas octopetala (0.9), Linnaea borealis (0.2), Vaccinium uliginosum ( 1 . 1 ), Pleurozium schreberi (0.2), Sphagnum girgensohnii (3.0), Cetraria aculeata ( <0. 1 ), Nephroma

expallidum ( <0. 1 ), Peltigera apthosa (0.2), Psoroma hypnorum ( <0. 1 )

4 : Festuca vivipara (0.2), Oxyria digyna (0.4), Pleurozium schreberi (0.3), Rubus chamaemorus (0.2), Salix polaris (5 .8), Trientalis europaea (0.2)

5 : Pyrola minor (0.2), Trientalis europaea (0.2), Vaccinium myrtillus (0.2), Polytrichastrum sexangulare (0.2), Racomitrium microcarpon (0.2), Peltigera scabrosa (0.2)

6: Cardamine bellidifolia (0.3), Lycopodium clavatum (0.3), Ceratodon purpureus (0.3)

7: Agrostis mertensii (0.3), Erigeron uniflorus ( <0. 1 ), Minuartia biflora ( <0. 1 ), Silene acaulis (0.8), Cladonia deformis ( <0. 1 ), Cladoniafimbriata ( <0. 1 ), Peltigera rufescens

( <0. 1 ), Psoroma hypnorum ( <0. 1 )

8 : Silene acaulis (0.6), Vaccinium uliginosum ( <0. 1 ), Cetraria aculeata ( <0. 1 ), Cladonia deform is ( <0. 1 ), Cladonia fimbriata ( <0. 1 ), crustaceous black (4.3)


Middle oroarctic vegetation in Finland and middle-northern arctic vegetation on Svalbard 5 1

Appendix 4. Mean percentage cover of plants in community types of the Salix herbacea group. 1 - Salix herbacea-Kiaeria type, 2 - Salix herbacea-Cassiope hypnoides type, 3 - Salix herbacea-Kiaeria type, Carex bigelowii variant, 4 - Carex bigelowii type, 5,6 - Cassiope hypnoides-Juncus trifidus type, 7 - Carex bigelowii-Salix polaris type, 8 - ]uncus trifidus-Cassiope tetragona type, Cetrariella delisei variant, 9 - Trisetum spicatum-Sanionia type. For frequencies, see Appendix 1 .

Agrosris mertensii

Antennaria alpina

Anthoxanthum odoratum

Bistorta vivipara

Cardamine bellidifolia

Carex bigelowii

Carex lachenalii

Cassiope hypnoides

Cassiope tetragona

Deschampsia flexuosa

Diphasiastrum alpinum

Erigeron uniflorus

Festuca ovina

Gnaphalium supinum

Hieracium sp.

Huperzia selago

}uncus biglumis

}uncus trifidus


Luzula spicata

Oxyria digyna

Phyllodoce caerulea

Poa alpina

Potentilla crantzii

Ranunculus acris

Ranunculus glacialis

Ranunculus nivalis

Rhodiola rosea

Salix herbacea

Salix polaris

Salix sp. Saussurea alpina

Sibbaldia procumbens

Silene acaulis

Taraxacum sp.

Trisetum spicatum

Vaccinium vitis-idaea

Vahlodea atropurpurea

Veronica alpina

Viola bijlora

Andreaea rupestris

Bryum sp.

Conostomum tetragonum


Die ranum fuscescens

Dicranum scoparium

Hylocomium splendens var. alaskanum

Kiaeria starkei

Mnium blyttii

Oligotrichum hercynicum

Pogonatum dentatum

Pogonatum urnigerum

Pohlia cruda

Pohlia spp.


Polytrichastrum sexangulare

Polytrichum commune

Polytrichum hyperboreum

Polytrichum juniperinum

Polytrichum piliferurn

Polytrichum sp.

2.2

1 .2

6.5

1 .2

1 .8

<0. 1

<0. 1

<0. 1

28.0

1 2. 1

Q.j_ <0. 1

<0. 1

3.3

26.2

<0. 1

0.7

0.3

4.2

2

0. 1

1 8.2

7.8

0. 1

0.9

0. 1

0.3

0.3

0. 1

0. 1

0. 1

13.8

0. 1

1 .5

0.3

0.9

1 .9

0. 1

0. 1

0.8

1 .8

u 1 .8

0.3

5.4

4.6

0.6

0.9

22.9

<0. 1

0.5

<0. 1

0.6

0.9

1 .0

<0. 1

<0. 1

29.2

0.3

7.3

0.3

<0. 1

1 . 1

0.3

0.3

<0. 1

ti

4

1 . 1

0.4

13.4

8.4

0.4

<0. 1

1 .8

0. 1

<0. 1

0. 1

0.5

0.3

1 .0

0. 1

0. 1

2.8

l . l

0.3

0.3

0.4

2.0

0. 1

u <0. 1

0.4

0.3

2. 1

0. 1

0.7

0.3

<0. 1

<0. 1

0.5

<0. 1

0.3

<0. 1

5 .2

0.3

1 .8

0.2

<0. 1

0.4

6.,2 2.3

0.3

<0. 1

0.3

<0. 1

<0. 1

0.9

0.4

<0. 1

<0. 1

0.5

<0. 1

<0. 1

<0. 1

<0. 1

<0. 1

<0. 1

0.2

<0. 1

<0. 1

0.4

0. 1

0.2

0.5

0.2

6

0.2

D <0. 1

19.5

0.2

<0. 1

<0. 1

7.1

<0. 1

<0. 1

1 .9

<0. 1

0.2

<0. 1

1 .0

0.5

1 .0

<0. 1

7

0.5

!U <0. 1

1 .8

8.5

!U 6.6

!U 0. 1

<0. 1

<0. 1

4.2

!U <0. 1

!U <0. 1

0.7

0.4

0.2

<0. 1

<0. 1

<0. 1

<0. 1

!U

<0. 1

0.3

8.2

0.4

<0. 1

0.3

0.7

<0. 1

0. 1

<0. 1

0.2

M <0. 1

0.2

<0. 1

<0. 1

0.3

<0. 1

0.2

0.2

<0. 1

0.5

2.4

0.3

8

0. 1

0.5

2.0

27.5

0.5

0. 1

5 .0

1 .0

0.5

1 .0

2.5

0.5

1 .5

0. 1

2.6

0.3

0.5

0. 1

0. 1

0. 1

0.6

9

0.3

<0. 1

7.4

<0. 1

2.0

9.2

2.0

0.2

4.8

0. 1

0.3

<0. 1

1.1 0.3

3.7

2.2

0.3

2.0

0.6

<0. I 1 .4

!U 0.2

1 . 1

<0. 1

0. 1

0.3

0.5

0.4

1 .0

u 0.6

<0. 1

M

0.3

1 .8

0.8

3 .3

0 .7



App. 4, continued.

Racomitrium microcarpon

Sanionia uncinata

Anastrophyllum minutum

Anthelia juratzknna

Barbilophozia floerkei

Barbilophozia hatcheri

Blepharostoma trichophyllum

Cephalozia spp.

Cephaloziella sp.

Diplophyllum taxifolium

Gymnomitrion apiculatum

Gymnomitrion concinnatum

Lophozia sudetica

Lophozia wentzelii

Lophozia spp.

Marsupella brevissima

Marsupella condensata

Pleurocladula albescens

Ptilidium ciliare

Tritomaria quinquedencata

Cetraria ericetorum

Cetraria islandica


Cetrariella delisei

Cladina arbuscula ssp. mitis

Cladonia bellidifolia

Cladonia coccifera

C/adonia ecmocyna

Cladonia gracilis


Cladonia pocillum

Cladonia pyxidata

Cladonia subfurcata

Cladonia uncia/is

Crustaceous black Crustaceous lichens

Ochrolechia frigida

Pertusaria dactylina

Solorina crocea


Stereocaulon pp.

Total

0.8

0.9

J.,2 8.9

2 3 4

Q,2 0.3 0.3

u J.,2 0.4

!1..8 4.6

0. 1

0. 1 0.3

0.3 0.3

Q,2 0. 1 {U

0.3 0.3

2.0 Q,2 3.5

0.2

0.3

5.5 2.3 J.&

0.5 0.9

0. 1 0.3

0.3 <0. 1

0.3 12 {U 0. 1

0.8 2.6 0.3 0.3 0.5 2.3

0.7 0.8 0.9

0.4 0.6

1 .0 0.8

0.3 0.3 Q2 0.5 1 .0 M

0.3

0.3

Q,1 <0. 1 0.9 M

0.6

0.2

ll Q,1 0.3

QJ. 0.3 Q,2 Q,1 M

1 34.7 9 1 .3 1 06.0

Additional species, occurring only in one or two clusters with a low frequency.

6 7

<0. 1 <0. 1

<0. 1 M

M 4.9 <0. 1

<0. 1 <0. 1

<0. 1

Q.j_ 0.2 <0. 1

0.4 1 . 1 0. 1 <0. 1

<0. 1 0.3 <0. 1

0. 1 <0. 1

0. 1 <0. 1

5.5 25.0 1 1 .1 0.4

0.3 u 2.0 <0. 1

0.2

Q,2 0.2

0. 1 2.2 0.6 <0. 1

0.5 !1..8 1 .0 1 .9

0.3 <0. 1

0.4 0.2

u D 2.7

<0. 1 u 0.3

0.7 Q,2 .u Q,2 4.3 1 .0 8.2 3.2

1 .5 2.0 <0. 1 1 2.8

0.2 <0. 1 <0. 1

0.5 0.4 !1..8 0.2

<0. 1 Q2 0.7 0.3 <0. 1 M

<0. 1 <0. 1

<0. 1 0.3 0.2 <0. 1 <0. 1

0.3 0.3 0.2 0.2 0.2 0.8 1 . 1

2.5 2..8 2J1 fL:1 1 .7 .u u

3.4 3.6 13.2 1 1.9

<0. 1 <0. 1 0. 1

0.3 QJ. Q,1 0.2 QJ. 0.3

M 0.2 0.2 <0. 1

74.6 76.6 95.6 86.4

I : Luzula multiflora ssp. frigida (0.3), Poa alpigena ( <0. 1 ), Diphysciumfoliosum (0.2), Moerchia blyttii ( <0. 1 )

8 9

15.3

0. 1 {U 0.3

0. 1 2.& QJ.

0.2

0.3

0. 1

0.5 <0. 1

0.3

0.5

2.5 u

20.0 <0. 1

1 .6 .L.Q

0.3 QJ. 0.3 0.2 0.3 QJ.

0.3

0.3 0. 1

0.3

<0. 1

0.3 0.6

16.5 D <0. 1

QJ. 0. 1 0.8

92. 1 87.0

2: Calamagrostis Lapponica (0.9), Carex vaginata (0. 1 ), Vaccinium myrtillus (0. 1 ), Dicranum elongatum (2.7), C/adonia crispata (0. 1 ), Cladonia turgida (0. 1 ), Peltigera

scabrosa (0.2), Stereocaulon paschale (0.9)

3: Calamagrostis lapponica (0.3), Diphysciumfoliosum (0. 1 ), Melanelia hepatizon ( 1 .8), Peltigera scabrosa (0.3)

4: Antennaria canescens (0. 1 ), Diapensia lapponica (0. 1 ), Racomitrium lanuginosum (0. 1 ), Sphagnum fimbriatum (0. 1 ), Thamnolia vermicularis (0. 1 )

5 : Erigeron humilis (0. 1 ) , Pohlia drummondii ( <0. 1 ) , Cladonia cervicornis ( <0. 1 ), Cladonia deformis (0. 1 ), Flavocetraria nivalis ( <0. 1 )

6 : Racomitrium lanuginosum ( 1 .0), Sphagnum fimbriatum (0. 1 ) , Cladonia cervicornis (0. 1 ) , Flavocetraria nivalis ( <0. 1 )

7 : Antennaria canescens (<0. 1 ), Antennaria porsildii (<0. 1 ), Cerastium arcticum (<0. 1 ), Erigeron humilis (<0. 1 ), Minuartia biflora (<0. 1 ), Poa alpigena (<0. 1 ), Thalictrum

alpinum ( <0. 1 ), Bartramia ithyphylla ( <0. 1 ), Distichium capillaceum ( <0. 1 ), Pohlia drummondii ( <0. 1 ), Cladina rangiferina ( <0. 1 ), Cladonia deformis ( <0. 1 ), Cladonia

fimbriata (<0. 1 ), Flavocetraria cucullata (0. 1 ), Melanelia hepatizon (<0. 1 ), Nephroma expallidum (<0. 1 )

8 : Antennaria lanata (0.5), Cerastium arctic urn (0.5), Empetrum nigrum ssp. hermaphroditum (0. 1 ) , Thamnolia vermicularis (0. 1 )

9: Carex vaginata (0. 1 ), Cerastium cerastoides ( <0. 1 ), Erigeron humilis (0. 1 ), Minuartia biflora (0. 1 ), Aulacomnium turgidum (0.3), Bartramia ithyphylla (0.3), Hylocomiastrum

pyrenaicum (0.3), Nephroma expallidum (0.6), Peltigera leucophlebia (0.6), Peltigera malacea (0.3), Peltigera rufescens ( <0. 1 )



Appendix 5. Mean percentage cover of plants in community types of the Ranunculus glacialis group. 1 - Anthelia-Polytrichastrum sexangulare type, 2 - Koenigia islandica-Phippsia algida community. For frequencies, see Appendix 1 .

2 2

Cardamine bellidifolia !U Philonotis sp. 2.5

Carex bigelowii 0. 1 0. 1 Pohlia drummondii QJ. Carex lachenalii !U 0. 1 Pohlia spp. .Q2 1 .8

Cassiope hypnoides 1 .4 Polytrichastrum alpinum 0.2 0.3

Cerastium arcticum <0. 1 Polytrichastrum sexangulare 7.9

Cerastium cerastoides 1 .8 Sanionia nivalis 4.0

Epilobium anagallidifolium <0. 1 1 .0 Tortula norvegica <0. 1

Equisetum arvense 4.0 Warnstorfia exannulata 10. 1

Gnaphalium supinum 1 .2

}uncus biglumis 0.4 Anthelia juratzkana 18.5 9.0

Koenigia islandica 5.1 Barbilophozia jloerkei 0. 1

Luzula arcuata ssp. confusa Q2 Cephalozia sp. 0.2 1 .5

Oxyria digyna 0. 1 Gymnomitrion apiculatum <0. 1

Phippsia algida 0. 1 Gymnomitrion concinnatum 9.:1 Phleum alpinum 1 .0 Gymnomitrion corallioides 6.2

Poa alpina !U. 0. 1 Lophozia sp. 1 . 1

Ranunculus acris 0. 1 Marsupella brevissima 0. 1

Ranunculus glacialis 0.3 Pleurocladula albescens .Q2 0.8

Ranunculus nivalis 0.4 Preissia quadrata <0. 1

Ranunculus pygmaeus <0. 1

Sagina nivalis <0. 1 Cetraria ericetorum <0. 1

Sali.x herbacea 1 .5 Cetraria islandica 0.9

Sali.x polaris 0.3 Cetraria islandica ssp. crispiformis 0.2

Saxifraga cernua 0. 1 Cetrariella delisei Q,2 0. 1

Saxifraga oppositifolia <0. 1 Cladina arbuscula ssp. mitis 0.4

Saxifraga stellaris 3.0 Cladonia coccifera 0.3

Saxifraga tenuis <0. 1 Cladonia ecmocyna <0. 1

Sibbaldia procumbens 2.,Q Cladonia gracilis !U Silene acaulis <0. 1 Cladonia pocillum 0. 1

Trisetum spicatum 0.3 Cladonia pyxidata 0. 1

Cladonia uncialis 0. 1

Andreaea rupestris Q,2 Crustaceous black 14.0

Bartramia ithyphylla <0. 1 0.5 Crustacous lichens 0. 1

Brachythecium sp. <0. 1 Ochrolechia frigida 0.4

Bryum sp. 8.5 Pertusaria sp. 0.4

Conostomum tetragonum 0.3 0. 1 Solorina crocea !U. Dicranoweisia crispula <0. 1 Stereocaulon rivulorum 0. 1

Kiaeria starkei 4,.0 Stereocaulon sp. M Oncophorus wahlenbergii 1 .5

Total 9 1 .7 59.3



Appendix 6. Mean percentage cover of plants in community types of the Saxifraga oppositifolia group. 1 - Salix polaris-Silene acaulis type, 2 - Saxifraga oppositifolia-Ranunculus sulphureus type, 3 - Dryas octopetala-Cassiope tetragona type. For frequencies, see Appendix 1 .

2 3 2

Arabis alpina 0.3 <0. 1 Mnium blyttii <0. 1 0.3 0.3

Bistorta vivipara 0.5 1 .3 Platydictya jungermannioides <0. 1 <0. 1

Cardamine bellidifolia <0. 1 <0. 1 Pogonatum umigerum <0. 1 <0. 1

Carex bigelowii Q,2 0.3 <0. 1 Pohlia cruda 0.2 <0. 1 0.2

Carex lachenalii 1 . 1 Pohlia spp. tU <0. 1 <0. 1

Cassiope hypnoides 2.6 M 0.3 Polytrichastrum alpinum <0. 1 0.2

Cassiope tetragona M 0.7 1 1 .7 Polytrichastrum sexangulare 0. 1 0.8

Cerastium arcticum 0.2 0.2 <0. 1 Polytrichum juniperinum <0. 1 <0. 1 <0. 1

Draba fladnizensis <0. 1 <0. 1 0.2 Sanionia uncinata !U <0. 1 <0. 1

Dryas ocropetala 0.2 3.2 36.7 Tayloria froelichiana <0. 1

Equisetum variegatum Q,2 Timmia austriaca 0.6

Erigeron humilis <0. 1 0.2 Tortella fragilis !U 3.3 0.3

Erigeron uniflorus 0.3 <0. 1 <0. 1 Tortula norvegica 0.2

Festuca ovina 0.4 0.3 0.4

Huperzia se/ago !U <0. 1 Anastrophyllum minutum 0.7 <0. 1 0.2

Luzula arcuata ssp. confusa 0.3 !U Anthelia juratzkana 1 .3 0.6 <0. 1

Luzula spicata <0. 1 <0. 1 <0. 1 Barbilophozia hatcheri 0.2 <0. 1

Oxyria digyna 0.3 <0. 1 Barbilophozia kunzeana 0.3 <0. 1

Poa alpigena <0. 1 <0. 1 Blepharostoma trichophyllum tU 0.2 0.2

Poa alpina 0.5 0.3 Preissia quadrata 0.3 0.2 <0. 1

Poa arctica M Scapania sp. <0. 1 <0. 1

Ranunculus nivalis 0. 1 <0. 1 Tritomaria quinquedentata 0.4 <0. 1

Ranunculus pygmaeus <0. 1 <0. 1

Ranunculus sulphureus � Cetraria ericetorum 0.2 4.7

Sagina nivalis <0. 1 <0. 1 Cetraria islandica 0. 1 <0. 1

Salix polaris 8.0 1 .4 .L.Q Cetraria islandica ssp. crispiformis Q,2 0.2 3 .3

Salix reticulata 0.3 Q,2 0.5 Cetrariella delisei u 0.6 2. 1

Saussurea alpina <0. 1 0.3 Cladina arbuscula ssp. mitis 0.8 .L.Q 1 .4

Saxifraga oppositifolia <0. 1 2.8 0.3 Cladonia coccifera ll <0. 1

Saxifraga tenuis 0.3 ll Cladonia gracilis ll <0. 1 0.2

Sibbaldia procumbens 0.3 1 .3 Cladonia pocillum tU 0.3 Q2 Silene acaulis 3.4 2.8 <0. 1 Cladonia symphycarpa Q2 Taraxacum sp. <0. 1 <0. 1 Cladonia uncialis <0. 1 <0. 1

Thalictrum alpinum <0. 1 0.3 Crustaceous black 2.& 29.8 5.3

Veronica alpina <0. 1 <0. 1 Crustaceous lichens <0. 1 1.& Ochrolechia frigida 2.8 2.6 1 . 1

Bryum p. 0.6 Q,2 Peltigera leucophlebia <0. 1 <0. 1

Dicranum scoparium 0.2 <0. 1 1 .7 Psoroma hypnorum <0. 1 <0. 1

Dicranum sp. 0.6 <0. 1 Solorina bispora <0. 1 0.2

Distichium capillaceum 0.5 2.6 0.3 Stereocaulon alpinum <0. 1 Q2 Encalypta alpina <0. 1 <0. 1 <0. 1 Stereocaulon botryosum <0. 1 <0. 1

Fissidens osmundoides <0. 1 0.4 Stereocaulon sp. ll <0. 1

Meesia uliginosa 0.2 <0. 1

Total 39.9 69.7 77.9


I : Cerastium cerastoides ( <0. 1 ), Draba daurica (0.2), Equisetum arvense (0. 1 ), Minuartia biflora ( <0. 1 ), Phyllodoce caerulea ( <0. 1 ), Potentilla crantzii (0.2), Saxifraga

cespitosa (0.2), Saxifraga nivalis (0.2), Trisetum spica rum (0. 1 ), Bartramia ithyphylla (0.2), Conostomum tetragonum ( <0. 1 ), Cyrtomnium hymenophylloides ( <0. 1 ),

Distichium inclinatum (0.4), Hylocomium splendens var. alaskanum (0. 1 ), Kiaeria starkei ( <0. 1 ), Barbilophoziafloerkei (0.2), Cephalozia sp. ( <0. 1 ), Marsupella brevissima

(0. 1 ), Odontoschisma macounii ( <0. 1 ), Cladonia pyxidata (0.2), Cladonia turgida ( <0. 1 )

2 : Antennaria porsildii (0.2), Gnaphalium supinum ( <0. 1 ) , Minuartia stricta ( <0. 1 ), Dicranoweisia crispula (<0. 1 ) , Loeskypnum badium (0.4), Mnium thomsonii (<0. 1 ),

Peltigera rufescens (0. 1 ), Psora decipiens ( <0. 1 ), Stereocaulon rivulorum ( <0. 1 )

3 : Anthoxanthum odoratum ( <0. 1 ) , Carex atrofusca ( <0. I ), Dicranum elongatum (0.7), Tritomaria scitula ( <0. 1 )



Appendix 7 . Mean percentage cover of plants in community types of the Luzula confusa group. 1 - Luzula confusa-Gymnomitrion corallioides community, 2 - Luzula confusa-Racomitrium lanuginosum community, 3 - Luzula confusa-Sanionia community. For frequencies, see Appendix 1 .

2 2 3

Alopecurus borealis <0. 1 <0. 1 Polytrichastrum alpinum 6.8 <0. 1 <0. 1

Bistorta vivipara 0.2 <0. 1 1 .0 Polytrichum juniperinum <0. 1 0.3 Cardamine bellidifolia <0. 1 3.2 Polytrichum pi life rum QJ_ Cerastium arcticum 0.4 Polytrichum strictum 0.8 <0. 1

Cochlearia groenlandica QJ_ Racomitrium canescens u 4.3 Draba alpina <0. 1 0.3 Racomitrium lanuginosum Qj_ l..U <0. 1

Draba oxycarpa <0. 1 <0. 1 Sanionia uncinata 5.9 8.4 24.2

Draba subcapitata <0. 1 <0. 1 Timmia austriaca <0. 1 <0. 1 0.7

Dryas octopetala 0.2 0.8 Tortula ruralis 1 .5 Ll Luzula arctica 0.3 Luzula arcuata ssp. confusa 1 1 .6 1 .2 1 1 .4 Anastrophyllum minutum <0. 1 <0. 1

Oxyria digyna 0.2 0.2 <0. 1 Cephaloziella arctica <0. 1 0.3

Pedicularis hirsuta QJ_ QJ_ Gymnomitrion concinnatum 2.9 <0. 1

Poa alpina <0. 1 0.5 Gymnomitrion corallioides 12.8 <0. 1

Poa arctica <0. 1 <0. 1 Ptilidium ciliare 4.3 Qj_ <0. 1

Potentilla hyparctica <0. 1 <0. 1 Tritomaria scitula 0.6 2.5

Ranunculus pygmaeus <0. 1 <0. 1

Salix polaris 1 1 . 1 5.9 9.3 Bryocaulon divergens <0. 1 <0. 1

Saxifraga cernua <0. 1 0.2 Cetraria aculeata 0.2 <0. 1 <0. 1

Saxifraga cespitosa <0. 1 0.2 0.8 Cetraria islandica !U 1J. Saxifraga hieracifolia <0. 1 <0. 1 Cetrariella delisei 10. 1 25.7 Q2 Saxifraga nivalis <0. 1 <0. 1 0.2 Cladina arbuscula ssp. mitis 0.2 2.6 QJ_ Saxifraga oppositifolia Ll 9.6 2.0 Cladonia amaurocraea <0. 1 QJ_ Silene acaulis 0.2 <0. 1 Cladonia cltlorophaea <0. 1 0.5

Stellaria Longipes coli . <0. 1 <0. 1 Cladonia coccifera QJ_ <0. 1 0.4

Cladonia ecmocyna <0. 1 <0. 1

Andreaea rupestris <0. 1 <0. 1 Cladonia gracilis 0.2 QJ_ 0.6

Aulacomnium palustre <0. 1 <0. 1 Cladonia pocillum <0. 1 0.5

Aulacomnium turgidum u 0.2 0.3 Cladonia pyxidata <0. 1 <0. 1

Barbula sp. <0. 1 0.4 Flavocetraria cucullata 0.3 0.2

Bryum sp. 1 .5 <0. 1 0.2 Flavocetraria nivalis 0.2 .L.1 Ceratodon purpureus 2.9 <0. 1 Ochrolechia frigida 7.9 5.4 1 .0

Conostomum tetragonum M <0. 1 Peltigera leucophlebia <0. 1 <0. 1

Dicranum angustum 1 .6 QJ_ 5.4 Peltigera rufescens Q2 0.4

Dicranum elongatum Q2 Psoroma hypnorum 3.,6 0.6 1 .8

Dicranum fuscescens 2. 1 1 .5 <0. 1 Rinodina turfacea 0.2 1 .7

Dicranum scoparium <0. 1 <0. 1 Solorina crocea <0. 1 <0. 1

Dicranum spadiceum <0. 1 0.3 0.2 Sphaerophorus globosus <0. 1 0.2

Distichium capillaceum 0.3 0.3 Stereocaulon alpinum 1 .4 2.2 u Hylocomium splendens var. alaskanum 4.2 Stereocaulon rivulorum 1 .4 0. 1 0.2

Hypnum revolutum 1 .4 1 .7 Stereocaulon saxatile 2 . 1 1 .7

Oncophorus wahlenbergii <0. 1 <0. 1 <0. 1 Stereocaulon vesuvianum 0.5 <0. 1

Pohlia cruda <0. 1 <0. 1 Stereocaulon sp. 0. 1 0.2

Thamnolia vermicularis QJ_ 0. 1 0.2

Total 1 1 6.2 90.6 89. 1


1 : Cassiope tetragona ( 10.7), Drabajladnizensis (<0. 1 ), Empetrum nigrum ssp. hermaphroditum (0. 1 ), Festuca brachyphylla (<0. 1 ), Huperzia selago (<0. 1 ), Minuartia

rubella (<0. 1 ), Pedicularis lanata ssp. dasyantha (<0. 1 ), Phippsia algida (<0. 1 ), Poa alpigena (0.3), Saxifraga hyperborea (<0. 1 ), Trisetum spicatum (<0. 1 ), B1yum

pallescens ( <0. 1 ), Kiaeria glacialis ( <0. 1 ), Polytrichum hyperboreum ( <0. 1 ), Odontoschisma macounii ( <0. 1 ), Scapania tundrae ( <0. 1 ), Tritomaria quinquedentala ( <0. 1 ),

Cetraria islandica ssp. crispiformis ( <0. 1 ), Cladonia cervicomis ( <0. 1 ), Cladonia macrophylla ( <0. 1 ), Cladonia macroceras ( <0. 1 ), Nephroma expallidum ( <0. 1 ), Peltigera

apthosa ( <0. 1 ), Stereocaulon glareosum (0.4)

2: Draba corymbosa ( <0. 1 ), Papaver dahlianum ( <0. 1 ), Ranunculus nivalis (0. 1 ), Cratoneuron sp. (0.6), Dicranum majus (0. 1 ), Alectoria nigricans ( <0. 1 ), Collema tenax

( <0. J ), Peltigera malacea ( <0. 1 ), Physconia muscigena (0. 1 )

3 : A renaria pseudofrigida ( <0. 1 ), Carex rupestris (3.3), Cerastium regelii ( <0. 1 ), Draba nivalis ( <0. 1 ), Equisetum arvense ( <0. 1 ), Hierochloe alpina (0.7), Minuartia bijlora

( <0. 1 ), Bartramia ithyphylla ( <0. 1 ), Brachythecium turgidum ( <0. 1 ), Climacium dendroides (0.2), Encalypta alpina ( <0. 1 ), Encalypta rhaptocarpa ( <0. 1 ), Hypnum vaucheri

(<O. l ), Schistidium apocarpum (<0. 1 ), Timmia norvegica (<0. 1 ), Tomentypnum nitens (<0. 1 ), Alectoria ochroleuca (<0. 1 )



Appendix 8. Mean percentage cover of plants in communities of the Papaver dahlianum group. 1 - Papaver dahlianum polar desert, 2 - Papaver dahlianum-Racomitrium panschii community. For frequencies, see Appendix 1 .

Alopecurus borealis

Bistorta vivipara

Cerastium arcticum

Draba alpina

Draba arctica

Draba corymbosa

Draba nivalis

Draba norvegica

Draba oxycarpa

Draba subcapitata

Dryas octopetala

Festuca hyperborea

Festuca rubra ssp. arctica

Luzula arctica


Minuartia bijlora

Minuartia rubella

Oxyria digyna

Papaver dahlianum

Pedicularis hirsuta

Phippsia algida

Poa arctica

Potentilla hyparctica

Potentilla pulchella

Sagina nivalis

Salix polaris

Saxifraga cemua

Saxifraga cespitosa

Saxifraga flagellaris

Saxifraga nivalis


Silene acaulis

Silene furcata

Stellaria longipes col i .

Bartramia ithyphylla

Ceratodon purpureus

Conostomum tetragonum

Cratoneuron sp.



0.2

Q,l

<0. 1

0.3

1 .6

0. 1

<0. 1

0.7

<0. 1

1 .6

0.2

Q,l

Q,l <0. 1

<0. 1

<0. 1

Q,l Q,l

2

<0. 1

<0. 1

0.2

<0. 1

<0. 1

<0. 1

<0. 1

<0. 1

Q,l 0.2

<0. 1

!U <0. 1

2.9

<0. 1

Q,l 0.2

0.3

Q2

0.4

<0. 1

<0. 1

0.2

4.4

<0. 1

0.7

<0. 1

0. 1

0.6

Q2 <0. 1

<0. 1

<0. 1

<0. 1

Dicranum spadiceum

Encalypta sp.

Hypnum revolutum

Hypnum vaucheri


Polytrichum hyperboreum

Polytrichum pi life rum

Polytrichum sp.

Racomitrium canescens

Racomitrium lanuginosum

Racomitrium panschii

Sanionia uncinata

Schistidium sp.

Tortula ruralis

Gymnomitrion corallioides

Alectoria nigricans

Caloplaca sp.

Cetraria aculeata


Cetrariella delisei

Cetrariella fastigiata

Cladonia coccifera

Cladonia chlorophaea


Cladonia pocillum

Cladonia sp.

Lecidea sp.

Nephroma expallidum

Ochrolechia frigida

Peltigera rufescens

Physconia muscigena

Psoroma hypnorum

Rinodina turfacea

Sphaerophorus globosus


Stereocaulon rivulorum

Stereocaulon sp.


Total

<0. 1

!U

<0. 1

<0. 1

<0. 1

Q,l

<0. 1

<0. 1

0.6

Q,l

<0. 1

<0. 1

<0. 1

0.2

<0. 1

Q,l <0. 1

0.3

<0. 1

Q,l 0.4

<0. 1

<0. 1

QJ. <0. 1

<0. 1

<0. 1

9.4

2

<0. 1

<0. 1

2.9

<0. 1

<0. 1

<0. 1

<0. 1

Q,2 <0. 1

4.9

<0. 1

!U. <0. 1

0.6

<0. 1

<0. 1

� 0.3

0.7

<0. 1

10.4

<0. 1

<0. 1

2&

0.4

<0. 1

<0. 1

0.2

36.7


Appendix 9. Mean percentage cover of plants in communities of the Dryas octopetala group. 1 - Dryas octopetala-Tomentypnum community, 2 - Dryas octopetala-Sanionia community, 3 - Dryas octopetala-Salix polaris community, 4 - Saxifraga oppositifoliaHypnum revolutum community. For frequencies, see Appendix 1 .

2 4 2 3 4

Alopecurus borealis 0.2 <0. 1 <0. 1 Dicranum elongatum <0. 1 <0. 1 Bistorta vivipara 4.6 4.5 1 .0 1 .2 Dicranum fuscescens 0. 1 0.8 Cardamine bellidifolia <0. 1 <0. 1 Dicranum spadiceum u <0. 1 Carex rupestris 0.3 <0. 1 Distichium capillaceum <0. 1 <0. 1 <0. 1 1.2 Cassiope tetragona 10. 1 0.2 1 1 .7 Distichium inclinatum <0. 1 <0. 1 Cerastium arcticurn 0.2 <0. 1 0.5 0.2 Ditrichurn jlexicaule Q,1 0.2 Cerastium regelii <0. 1 <0. 1 0. 1 Hylocorniurn splendens var. alaskanum 16.8 u <0. 1

Hypnum revolutum M <0. 1 b2 � Draba alpina Q,1 {ll Q,1 0.2 Polytrichastrum alpinum <0. 1 Q,1 0.2 <0. 1 Draba norvegica <0. 1 <0. 1 <0. 1 Polytrichum juniperinurn 0.5 Qd Draba subcapicata 0.2 <0. 1 <0. 1 {ll Polytrichum piliferurn 0.2 <0. 1 Dryas octopetala 16.9 23.1 15.3 1 .6 Racornitrium canescens 0.8 2.5

Equisetum scirpoides 4.5 Sanionia uncinata 0.2 29.9 5 .0 u Festuca rubra ssp. arctica <0. 1 l.J. 0.5 <0. 1 Schistidium apocarpurn 0.3 <0. 1 Festuca vivipara <0. 1 <0. 1 0. 1 Timmia austriaca Q,1 Q,1 }uncus biglumis <0. 1 <0. 1 <0. 1 Tomentypnum nitens 10.8 7.0 10.8 Luzula arctica 1 .0 {ll 0.2 <0. 1 Tortula ruralis <0. 1 M <0. 1 Luzula arcuata ssp. confusa 9.4 1 .3 0.3 2.5 Minuartia rossii <0. 1 <0. 1 Gymnornitrion corallioides u Minuartia rubella <0. 1 0.2

Oxyria digyna Qd <0.1 <0. 1 <0. 1 Buellia papillata <0. 1 2.2 Papaver dahlianum <0. 1 {ll <0. 1 {ll Cetraria aculeata <0. 1 <0. 1 Pedicularis hirsuta 0.3 0.2 <0. 1 Q,1 Cetraria islandica <0. 1 {ll Pedicularis lanata ssp. dasyantha <0. 1 gu <0. 1 Cetraria islandica ssp. crispiformis <0. 1 <0. 1 Poa alpigena Q2 0. 1 Cetrariella delisei 0. 1 <0. 1 Poa alpina 0.2 <0. 1 Cladonia chlorophaea Q,1 Poa arctica 0.3 Qd 1 . 1 0.2 Cladonia gracilis 0. 1 <0. 1 <0. 1 Potentilla hyparctica <0. 1 <0. 1 Cladonia pocilllurn Q,1 <0. 1 Sagina nivalis Q,1 <0. 1 Cladonia pyxidata <0. 1 <0. 1 <0. 1 Salix polaris 1 1 .4 1 2.8 10.5 5.3 Flavocetraria nivalis <0. 1 <0. 1 Saxifraga cemua <0. 1 <0. 1 0. 1 Q,1 Lecidea sp. <0. 1 1 .7 0.7 Saxifraga cespitosa <0. 1 <0. 1 <0. 1 0. 1 Nephroma expallidum 0.2 0.2 Saxifraga jlagellaris <0. 1 Q,1 Ochrolechia frigida 7.9 7.4 1 .7 8.7

Saxifraga nivalis <0. 1 <0. 1 <0. 1 <0. 1 Peltigera leucophlebia Qd <0. 1 Q2 Saxifraga oppositifolia 0. 1 1 .8 1 . 1 6.9 Peltigera rufescens ll 0.2 ll Silene acaulis <0. 1 0. 1 Physconia muscigena <0. 1 <0. 1 <0. 1 Si le ne furcata {ll Psororna hypnorum 2.7 l . l Silene uralensis <0. 1 <0. 1 Rin.odina turfacea Qd <0. 1 Stellaria longipes coli . 0.3 ll Q,1 <0. 1 Solorina crocea <0. 1 <0. 1

Sphaerophorus globosus <0. 1 <0. 1 Aulacomnium turgidum 5.9 0.4 (U Stereocaulon alpinum 0.8 <0. 1 2.5 Bartrarnia ithyphylla 0.2 <0. 1 Stereocaulon rivulorurn <0. 1 lJ2 u Qd Brachytheciurn turgidum <0. 1 <0. 1 Stereocaulon saxatile <0. 1 <0. 1 Bryurn pallescens <0. 1 0.2 Stereocaulon sp. 3. 1 <0. 1 Bryum spp. < 0. 1 <0. 1 <0. 1 <0. 1 Thamnolia verrnicularis 0.2 {ll 0. 1 {ll Cratoneuron sp. <0. 1 5 .7 Cyanobacteria 2.3 13.6 Dicranum angusturn 0. 1 3.3

Total 1 22.5 1 1 4.8 75.2 60.6


1 : Saxifraga foliolosa (< 0. 1 ), Ceratodon purpureus (<0. 1 ), Dicranurn rnajus ( 1 .4), Kiaeria glacialis (<0. 1 ), Oncophorus virens (<0. 1 ), Oncophorus wahlenbergii (<0. 1 ),

Polytrichastrurn sexangulare ( <0. 1 ), Polytrichum strictum ( <0. 1 ), Racomitrium ericoides (0. 1 ), Racornitrium panschii (0.2), Racornitriurn sudeticum ( <0. 1 ), Blepharostoma

trichophyllurn (0.2), Gyrnnornitrion concinnaturn (<0. 1 ), Odontoschisma macounii (0.7), Ptilidiurn ciliare (0.8), Tritomaria scitula (<0. 1 ), Alectoria nigricans (<0. 1 ),

A rctocetraria nigricascens ( <0. 1 ), Cladonia amaurocraea ( <0. 1 ), Cladonia macrophylla ( <0. 1 ), Cladonia rnacroceras ( <0. 1 ), Peltigera malacea ( <0. 1 ), Solorina octospora

(<0. 1 )

2 : Draba corymbosa ( <0. 1 ) , Equisetum variegatum (0.2), Phippsia algida ( <0. 1 ) , Trisetum spicatum ( <0. 1 ) , Encalypta rhaptocarpa ( <0. 1 ), Timmia norvegica ( <0. 1 ),

Cephaloziella arctica ( <0. 1 ), Tetralophozia setiformis ( 1 . 1 ), Cladonia coccifera ( <0. 1 ), Peltigera apthosa ( <0. 1 )

3 : Polemonium boreale ( <0. 1 ) , Saxifraga hieracifolia ( <0. 1 ) , Abietinella abietina ( <0. 1 ), Fulgensia bracteata ( <0. 1 ) , Peltigera canina ( <0. 1 ) , Solorina bispora ( <0. 1 )

4 : Festuca brachyphylla (<0. 1 ), Festuca hyperborea (<0. 1 ), Min.uartia bijlora (<0. 1 ), Potentilla pulchella (<0. 1 ), Campylium stellatum (0. 1 ), Encalypta alpina (<0. 1 ),

Encalypta streptocarpa (<0. 1 ) , Stereocaulon glareosum (0. 1 )


58 R. Virtanen & S . Eurola

Appendix 1 0. Mean percentage cover of plants in the moss tundra communities. 1 - Sanionia-Saxifraga hyperborea community, 2 -Aulacomnium turgidum-Alopecurus borealis community, 3 - Aulacomnium turgidum-Hylocomium community, 4 - Racomitrium canescens-Oxyria community. For frequencies, see Appendix 1 .

2 4 2 3 4

Alopecurus borealis 0.3 10.3 8.8 2.3 Polytrichum pi life rum lU <0. 1 Bistorta vivipara <0. 1 1 .4 1 .3 2.5 Polytrichum strictum 0.5 0.2 0.2 Cardamine bellidifolia <0. 1 <0. 1 lU Racomitrium canescens <0. 1 1 . 1 17.3

Cassiope tetragona 20.2 Racomitrium ericoides <0. 1 <0. 1 Cerastium arcticum <0. 1 <0. 1 lU Racomitrium lanuginosum 0.3 <0. 1 Cerastium regelii lU Sanionia uncinata 35.2 6.3 16.6 10.1

Draba micropetala <0. 1 <0. 1 Sarmentypnum sarmentosum 6.8 8.3 4.0 Equisetum arvense <0. 1 1 .3 <0. 1 Scorpidium revolvens 6.3 <0. 1 Equisetum variegatum <0. 1 <0. 1 Timmia austriaca <0. 1 <0. 1 .L.Q Luzula arctica 0.4 0.3 0.7 lU Tomentypnum nitens 4.1 0.7 8.0

Luzula arcuata ssp. confusa 2.4 3.8 7.4 10.6

Oxyria digyna M <0. 1 0.7 Anastrophyllum minutum <0. 1 0.5 lU Pedicularis hirsuta lU 0.3 <0. 1 Anthelia juratzkana lU Poa alpigena 0.5 il 1 .7 Blepharostoma trichophyllum 0.9 3 . 1 5.2

Poa alpina <0. 1 <0. 1 Cephaloziella arctica <0. 1 2.5 .u <0. 1 Poa arctica <0. 1 1 .3 0.3 0.3 Cephalozia sp. 0.8 0.7 Potentilla hyparctica <0. 1 <0. 1 Gymnomitrion concinnatum J..Q,_8_ Ranunculus pygmaeus 0.2 Gymnomitrion cora/lioides 1 .3 0.2 0.6 0.4 Ranunculus sulphureus <0. 1 0.3 lU <0. 1 Lophozia wenzelii 0.3 <0. 1 <0. 1 Sagina nivalis <0. 1 <0. 1 Marsupella boeckii 0.2 6.3 <0. 1 Salix polaris 2.3 15.0 25.5 13.2 Odontoschisma macounii lU <0. 1 0.5 <0. 1 Saxifraga cernua <0. 1 lU <0. 1 <0. 1 Ptilidium ciliare <0. 1 0.3 <0. 1 .L2 Saxifraga cespitosa <0. 1 lU <0. 1 Tritomaria quinquedentata 1 . 1 0.7 <0. 1 Saxifraga foliolosa lU 0.2 0. 1 Tritomaria scitula 0.8 lU Saxifraga hieracifolia lU Saxifraga hirculus <0. 1 <0. 1 Candelariella sp. <0. 1 <0. 1 Saxifraga hyperborea 0.2 <0. 1 Cetraria islandica <0. 1 lU Saxifraga nivalis <0. 1 lU <0. 1 Cetraria islandica ssp. crispiformis <0. 1 <0. 1 Saxifraga oppositifolia 1 .0 <0. 1 <0. 1 Cetraria nigricans <0. 1 <0. 1 Stellaria longipes coli . 0.2 0.3 0.3 Cetrariella delisei <0. 1 <0. 1 <0. 1 <0. 1

Cladonia amaurocraea <0. 1 lU Aulacomnium turgidum 0.5 1 7.8 2 1 .8 13.7 Cladonia chlorophaea 0.2 <0. 1 0.2 <0. 1 Bartramia ithyphylla <0. 1 lU lU Cladonia coccifera 0. 1 lU <0. 1 Bryum cryophilum 0. 1 Cladonia gracilis 0.2 <0. 1 <0. 1 0.4

Bryum spp. <0. 1 3.8 Cladonia macrophylla <0. 1 <0. 1 lU Calliergon stramineum <0. 1 .u Cladonia pocillum lU <0. 1 0.2 Conostomum tetragonum 0.2 1 .4 0.2 <0. 1 Cladonia pyxidata <0. 1 <0. 1 Cratoneuron sp. <0. 1 <0. 1 0. 1 Nephroma expallidum 0.2 0.7 Dicranum angustum lL.8. 7.5 .8.3. 2d Ochrolechia frig ida 2.8 0.3 1 .5 2.0 Dicranum elongatum <0. 1 2.2 0.8 Peltigera apthosa <0. 1 Q2 <0. 1 Dicranum fuscescens 0.8 M 2.4 Peltigera canina 0.2 Q,2 0.3 Dicranum majus <0. 1 1 2.6 <0. 1 Q,2 Peltigera leucophlebia 0.3 0.7 Qj_ Dicranum spadiceurn <0. 1 0.4 Q,2 Peltigera rufescens <0. 1 0.6 <0. 1 lU Distichium capillaceurn <0. 1 <0. 1 Psoroma hypnorum <0. 1 0.2 0.4 Q,2 Ditrichum flexicaule 3 . 1 <0. 1 Rinodina turfacea lU Hylocomium splendens var. alaskanum lU 7.2 3.7 Solorina crocea <0. 1 lU <0. 1 Kiaeria glacialis 0.7 0. 1 Stereocaulon alpinum 0.3 0.6 2 . 1 Meesia uliginosa 0.5 <0. 1 Stereocaulon glareosum 0.5 <0. 1 Oncophorus virens lU <0. 1 <0. 1 Stereocaulon rivulorum 0.8 <0. 1 3.7 Oncophorus wahlenbergii 0.2 <0. 1 0.4 Stereocaulon saxatile <0. 1 0.4 Pohlia nutans <0. 1 <0. 1 Stereocaulon vesuvianum 0.5 <0. 1 Pohlia spp. 0.2 <0. 1 Stereocaulon sp. <0. 1 1 .4 1 .0 Polytrichastrum alpinum 1 0. 1 D_ M Thamnolia vermicularis lU lU <0. 1 Polytrichurn juniperinum 0.6 0.3 0.3

Total 1 0 1 .3 1 30. 1 1 34.6 144.3

Additional species, occurring only in one or two clusters with a low frequency. I : Campylium stellatum ( <0. 1 ) , Dicranoweisia crispula ( <0. 1 ), Loeskypnum badium ( <0. 1 ), Polytrichastrum sexangulare ( <0. 1 ), Lophozia opacifolia ( <0. 1 ), Scapania tundrae ( <0. 1 ), Cladonia bellidijlora ( <0. 1 ), Cladonia cervicornis ( <0. 1 ), Cladonia macroceras ( <0. 1 ), Cladina arbuscula ssp. mitis ( <0. 1 ), Physconia muscigena ( <0. 1 )

2 : Draba corymbosa ( <0. 1 ), Equisetum scirpoides (0.3), Aulacomnium palustre ( <0. 1 ), Cirriphyllum cirrosum ( <0. 1 ) , Cynodontium strumiferum ( <0. 1 ) , Hypnum vaucheri (<0. 1 ), Meesia triquetra (<0. 1 ), Orthothecium chryseum (<0. 1 ), Philonotis fontana (<0. 1 ), Platydictya jungermannioides (<0. 1 ), Tortula ruralis (<0. 1 ), Tetralophozia setiformis (2.5), Collema tenax (2.5)

3: Drabajladnizensis ( <0. 1 ), ]uncus biglumis (0. 1 ) , Koenigia islandica (0. 1 ), Papaver dahlianum ( <0. 1 ), Saxifraga jlagellaris ( <0. 1 ), Hypnum recurvatum ( <0. 1 ), Hypnum revolutum (0.6), /sopterygiopsis pulchella (<0. 1 ), Kiaeria starkei (<0. 1 ), Polytrichum hyperboreum (0. 1 ), Caloplaca sp. (<0. 1 ), Cetraria aculeata (<0. 1 ), Collema limosum ( <0. 1 ), Sphaerophorus globosus ( <0. 1 ), Stereocaulon tomentosum ( <0. 1 ) 4 : Draba alpina ( <0. 1 ), Draba norvegica ( <0. 1 ), Draba oxycarpa ( <0. 1 ), Draba subcapitata ( <0. 1 ), Dryas octopetala (0.4), Huperzia se/ago ( <0. 1 ), Pedicularis lanata ssp. dasyantha (<0. 1 ), Silenefurcata (<0. 1 ), Pogonatum dentatum (2. 1 ), Scapania irriqua (<0. 1 ), Alectoria nigricans (<0. 1 ), Buellia papillata (<0. 1 ), Peltigera malacea (<0. 1 )



Appendix 1 1 . Mean percentage cover of plants in the Sanionia snow bed communities. 1 - Sanionia snowbed, 2 - Sanionia-Poa alpigena snowbed. For frequencies, see Appendix 1 .

2

Alopecurus borealis 0.5 0.4 Dicranum majus <0. 1

Bistorta vivipara 1 .2 Dicranum spadiceum <0. 1

Cardamine bellidifolia <0. 1 Ditrichum jlexicaule <0. 1

Cardamine pratensis ssp. polemonioides <0. 1 Hylocomium splendens var. alask.anum 0.6 3 .8

Cerastium arcticum 1 . 1 0.6 Hypnum bambergeri <0. 1

Cerastium regelii 0.2 0.2 Oncophorus wahlenbergii 0.3

Cochlearia groenlandica 0.2 <0. 1 Philonotis tomentella 1 .3

Deschampsia alpina <0. 1 Pohlia cruda <0. 1

Draba alpina <0. 1 Pohlia spp. 0.8 <0. 1

Draba corymbosa <0. 1 Polytrichastrum alpinum 0.2 4.5

Draba Lactea <0. 1 Polytrichastrum sexangulare 0.7

Draba subcapitata <0. 1 Polytrichum juniperinum 0.4

Dupontia fisheri u Polytrichum strictum <0. 1

Equisetum arvense bQ Racomitrium canescens <0. 1 <0. 1

Equisetum variegatum 0.2 Racomitrium Lanuginosum <0. 1

Luzula arctica <0. 1 Sanionia uncinata 58.1 45.4

Luzula arcuata ssp. confusa u 2.0 Sarmentypnum sarmentosum <0. 1

Minuartia bijlora <0. 1 Timmia austriaca 0.6 <0. 1

Oxyria digyna 0.3 Q,2 Tomentypnum nitens <0. 1 4.2

Pedicularis hirsuta <0. 1 Tortula ruralis 0.3

Phippsia algida <0. 1 <0. 1

Poa abbreviata <0. 1 Cephaloziella arctica 2.5 <0. 1

Poa alpigena <0. 1 1 0. 1 Gymnomitrion corallioides 0.8

Poa alpina 0.2 <0. 1 Hepaticae spp. 5 .0

Poa arctica 0.6 Marsupella sp. 0.3

Ranunculus pygmaeus <0. 1 0.3 Ptilidium ciliare 0.8

Ranunculus sulphureus 0.3 0.3 Tritomaria quinquedentata <0. 1

Sagina nivalis <0. 1

Salix polaris 2.9 2,.2 Cetraria islandica 1 .9

Saxifraga cemua 0.4 Q2 Cctrariclla dclisei LQ <0. 1

Saxifraga cespitosa !U !U Cladina arbuscula ssp. mitis <0. 1

Saxifraga foliolosa <0. 1 <0. 1 Cladonia amaurocraea <0. 1

Saxifraga hieracifolia <0. 1 Cladonia chlorophaea <0. 1 0. 1

Saxifraga hirculus <0. 1 Cladonia gracilis 0.2 <0. 1

Saxifraga hyperborea 0. 1 !U Cladonia pocillum <0. 1 <0. 1

Saxifraga nivalis <0. 1 !U Cladonia sp. <0. 1

Saxifraga oppositifolia .L1 0.3 Flavocetraria cucullata <0. 1

Saxifraga rivularis 0.3 <0. 1 Flavocetraria nivalis <0. 1

Silene acaulis <0. 1 Lecidea sp. <0. 1

Stellaria longipes coi l . 0. 1 0.2 Ochrolechia frigida <0. 1 0.3

Trisetum spicatum <0. 1 Peltigera apthosa <0. 1

Peltigera canina 0.4

Aulacomnium pa/ustre 5 .7 0. 1 Peltigera leucophlebia 0. 1

Aulacomnium turgidum 3.0 2.8 Peltigera rufescens 0.7 <0. 1

Bartramia ithyphylla 0.2 Psoroma hypnorum <0. 1

Brachythecium turgidum 0.2 Rinodina turfacea <0. 1

Bryum cryophilum <0. 1 0.4 Stereocaulon alpinum u Bryum sp. <0. 1 0.5 Stereocaulon glareosum <0. 1

Calliergon stramineum 6.3 0.5 Stereocaulon rivulorum <0. 1 0.3

Campylium stellatum <0. 1 Stereocaulon tomentosum 1 .3

Ceratodon purpureus 2.5 Stereocaulon sp. <0. 1 0.7

Cratoneuron sp. <0. 1 <0. 1 Thamnolia vermicularis <0. 1 <0. 1

Dicranum angustum 5.0

Dicranum fuscescens <0. 1 Total 1 03. 1 1 03.8



Appendix 1 2. Mean percentage cover of plants in wet snowbed communities. The Scorpidium revolvens-Tomentypnum community. For frequencies, see Appendix 1 .

Alopecurus borealis 0.8 Campylium stellatum 1 .8

Bistorta vivipara 8.0 Cinclidium arcticum 0.2

Calamagrostis stricta 0.8 Distichium capillaceum � Carex bigelowii 0.5 Ditrichum flexicaule <0. 1

Cerastium arcticum <0. 1 Fissidens osmundoides <0. 1

Cerastium regelii 0.2 Hygrohypnum luridum 0.8

Deschampsia alpina 0.2 Hylocomium alaskanum <0. 1

Draba alpina <0. 1 Meesia uliginosa <0. 1

Dupontia fisheri 0.2 Orthothecium chryseum lU Equisetum arvense 3.0 Sanionia uncinata 8.5

Equisetum variegatum 7.1 Sarmentypnum sarmentosum 5.0

Oxyria digyna 0.7 Scorpidium revolvens 28.4

Pedicularis hirsuta <0. 1 Tayloria Ungulata <0. 1

Phippsia algida <0. 1 Timmia austriaca <0. 1

Poa alpigena kQ Tomentypnum nitens 17.3

Poa alpina !U Tortella fragilis 0.5

Poa arctica 0.3 Tortula ruralis <0. 1

Ranunculus nivalis gu Ranunculus sulphureus 0.3 An thelia juratzkana 0.5

Salix polaris 2.4 Lophozia sudetica <0. 1

Saxifraga cemua Q2 Saxifraga foliolosa <0. 1 Cetrariella delisei <0. 1

Saxifraga hieracifolia <0. 1 Cladonia pocillum <0. 1

Saxifraga hirculus Q,2 Cladonia sp. <0. 1

Saxifraga hyperborea <0. 1 Crustaceous black 1 0. 1

Saxifraga nivalis <0. 1 Crustaceous bchens M Saxifraga oppositifolia .LQ Flavocetraria nivalis <0. 1

Silene acaulis 0.3 Peltigera apthosa <0. 1

Taraxacum sp. <0. 1 Peltigera leucophlebia <0. 1

Peltigera rufescens <0. 1

Aulacomnium turgidum Q2 Solorina bispora <0. 1

Brachythecium turgidum <0. 1 Stereocaulon alpinum <0. 1

Bryum pallescens 1 .7 Stereocaulon sp. � Bryum sp. 7.5

Calliergon orbiculari·cordatum <0. 1 Total 1 1 8.7


Svenska Viixtgeografiska Sallskapet 6 1

SVENSKA V AxTGEOGRAFISKA SALLSKAPET SOCIETAS PHYTOGEOGRAPHICA SUECANA

Adress: Viixtbiologiska Institutionen, Villavagen 14, S- 752 36 Uppsala, Sweden

Sallskapet har till andama.I att vacka och underha.Ila intresse for vaxtgeografien i vidstrackaste mening, att framja utforskande av flora och vegetation i Sverige och andra lander och att havda geobotanikens praktiska och vetenskapliga betydelse.

Sallskapet anordnar sammankomster och exkursioner samt utger tva publikationsserier. Medlemskap kan erha.Ilas efter anmalan hos sekreteraren. Foreningar, bibliotek, laroanstalter och andra institutioner kan inga som abonnenter.

Sallskapet utger arligen Acta Phytogeographica Suecica. Medlemmar och abonnenter erhiller arets Acta mot postfOrskott pa arsavgiften jamte porto och expeditionskostnader.

Vissa ar utges extra band av Acta, som erha.Ils mot en til laggsavgift.

Sallskapet har tidigare utgivit den ickeperiodiska serien Studies in Plant Ecology (vols. 1 - 1 9 Vaxtekologiska studier). Den kan fOrvarvas efter bestillning hos OPULUS PRESS AB, Box 25 1 37, 750 25 Uppsala, Sweden.

The object of the Society is to promote investigations in flora and vegetation, their history and their ecological background. Through publication of monographs, and other activities, the society tries to stimulate geobotanical research and its application to practical and scientific problems.

Individual members and subscribers (societies, institutes, libraries, etc. ) receive Acta Phytogeographica Suecica on payment of the annual membership fee. There are additional fees in years when more than one volume is issued. For membership please, apply to the Secretary.

The Society also issues Studies in Plant Ecology (vols. 1 - 1 9 Vaxtekologiska studier), which appears irregularly and can be ordered through OPULUS PRESS AB, Box 25 1 37, 750 25 Uppsala, Sweden or by standing order.

ACTA PHYTOGEOGRAPHICA SUECICA

1 . E. Almquist. 1 929. Upplands vegetation och flora. (Veg-etation and flora of Uppland. ) Out of print.

2. S. Thunmark. 1 93 1 . Der See Fiolen und seine Vegetation. ISBN 9 1 -72 1 0-002-8. Price: 240 SEK.

3. G. E. Du Rietz. 1 93 1 . Life-forms of terrestrial flowering plants. I. ISBN 9 1 -72 1 0-003-6. Price: 1 60 SEK.

4. B. Lindquist. 1 932. Om den vildvaxande skogsalmens raser och deras utbredning i Nordvasteuropa. (Summary: The races of spontaneous Ulmus glabra Huds. and their distribution in NW Europe. ) Out of print.

5 . H. Osvald. 1 933. Vegetation of the Pacific coast bogs of North America. ISBN 9 1 -72 1 0-005-2. Price: 1 60 SEK.

6. G. Samuelsson. 1 934. Die Verbreitung der hoheren Wasserpflanzen in Nordeuropa. 1 934. Out of print.

7. G. Degelius. 1 935. Das ozeanische Element der Strauch und Laubflechtenflora von Skandinavien. Out of print.

8. R. Semander. 1 936. Granskar och Fiby urskog. En studie over stormluckomas och marbuskamas betydelse i den svenska granskogens regeneration. (Summary: The primitive forests of Granskar and Fiby. A study of the part played by storm-gaps and dwarf trees in the regeneration of the Swedish spruce forest .) ISBN 9 1 -72 1 0-008-7. Price: 240 SEK.

9. R. Stemer. 1 938. Flora der Insel bland. Die Areale der Gefasspflanzen Glands nebst Bemerkungen zu ihrerOekologie und Soziologie. ISBN 9 1 -72 1 0-009-5. Out of print.

1 0. B. Lindquist. 1 938 . Dalby Soderskog. En skansk lOvskog i fomtid och nutid. (Zusarnmenfassung: Ein Laubwald in Schonen in der Vergangenheit und Gegenwart.) ISBN 9 1 -72 1 0-0 1 0-9. Price: 240 SEK.

1 1 . N. Stalberg. 1 939. Lake Vattem. Outlines of its natural history, especially its vegetation. ISBN 9 1 -72 1 0-0 1 1 -7 . Price: 1 60 SEK.

1 2. G. E. Du Rietz, A. G. Hannerz, G. Lohammar, R. Santesson & M. Warn. 1 939. Zur Kenntnis der Vegetation des Sees Talcem. ISBN 9 1 -72 1 0-01 2-5 . Price: 1 60 SEK.

1 3 . Vaxtgeografiska studier tillagnade Carl Skottsberg pa sextioarsdagen 1 1 1 2 1940. (Geobotanical studies dedicated to C. Skottsberg.) 1 940. ISBN 9 1 -72 1 0-0 1 3-3 . Price: 290 SEK.

14. N. Hylander. 194 l . De svenska formema av Menthagentilis L. coli. (Zusammenfassung: Die schwedischen Formen der Mentha gentilis L. sensu coli.) ISBN 9 1 -72 1 0-0 1 4- 1 . Price: 160 SEK.

15 . T. E. Hasselrot. 194 1 . Till kannedom om nagra nordiska umbilicariaceers utbredning. (Zusammenfassung: Zur Kenntnis der Verbreitung einiger Umbilicariaceen in Fennoscandia.) ISBN 9 1 -7210-015-X. Price: 240 SEK.

16. G. Samuelsson. 1943 . Die Verbreitung der AlchemillaArten aus der Vulgaris-Gruppe in Nordeuropa. ISBN 9 1 -7210-016-8. Price: 160 SEK.

1 7 . Th. Arwidsson. 1943. Studien i.iber die Gefasspflanzen in den Hochgebirgen der Pite Lappmark. ISBN 9 1 -72 1 0-0 1 7-6. Price: 240 SEK.

1 8 . N. Dahlbeck. 1 945. Strandwiesen am si.idostlichen Oresund. (Summary: Salt marshes on the S. E. coast of Oresund.) ISBN 9 1 -72 1 0-0 1 8-4. Price: 1 60 SEK.

1 9. E. von Krusenstjema. 1 945 . Bladmossvegetation och bladmossflora i Uppsalatrakten. (Summary: Moss flora and moss vegetation in the neighbourhood of Uppsala.) ISBN 9 1 -72 1 0-0 1 9-2. Price: 290 SEK.


62 Svenska Viixtgeografiska Siillskapet

20. N. Albertson. 1 946. 6sterplana bed. Ett alvaromrade pa Kinnekulle. (Zusarnmenfassung: 6sterplana bed. Ein Alvargebiet auf dem Kinnekulle.) ISBN 9 1 -72 1 0-020-6. Price: 240 SEK.

2 1 . H. SjOrs. 1 948. Myrvegetation i Bergslagen. (Summary: Mire vegetation in Bergslagen, Sweden.) ISBN 9 1 -72 1 0-02 1 -4. Price: 290 SEK.

22. S. Ahlner. 1 948. Utbredningstyper bland nordiska barrtradslavar. (Zusammenfassung: Verbreitungstypen unter fennoskandischen N adelbaumflechten.) ISBN 9 1 -72 1 0-022-2. Price: 240 SEK.

23. E. Julin. 1 948. Vessers udde, mark och vegetation i en igenvaxande lOvang vid B jarka-Saby. (Zusarnrnenfassung: Vessers udde. Boden und Vegetation in einer verwachsenden Laubwiese bei Bj arka-Saby in 6stergotland, Si.idschweden.) ISBN 9 1 -72 1 0-023-0. Price: 240 SEK.

24. M. Fries. 1 949. Den nordiska utbredningen av Lactuca alpina, Aconitum septentrionale, Ranunculus platanifolius och Polygonatum verticillatum. (Zusarnrnenfassung: Die nordische Verbreitung von Lactuca alpina.) ISBN 9 1 -72 1 0-24-9. Price: 1 60 SEK.

25 . 0. Gjterevoll. 1 949. Sn�leievegetasjonen i Oviksfjellene. (Summary: The snow-bed vegetation of Mts Oviksfjallen, Jamtland, Sweden.) ISBN 9 1 -72 1 0-025-7. Price: 1 60 SEK.

26. H. Osvald. 1 949. Notes on the vegetation of British and Irish mosses. ISBN 9 1 -72 1 0-026-5. Price: 1 60 SEK.

27. S. Selander. 1 950. Floristic phytogeography of southwestem Lule Lappmark (Swedish Lapland). I . 1 950. ISBN 9 1 -72 1 0-027-3. Price: 240 SEK.

28. S. Selander. 1 950. Floristic phytogeography of southwestem Lule Lappmark (Swedish Lapland). I I . Karlvaxtfloran i sydvastra Lule Lappmark. (Summary: Vascular flora.) ISBN 9 1 -72 1 0-028- 1 . Price: 1 60 SEK.

29. M. Fries. 1 95 1 . Pollenanalytiska vittnesbord om senkvartar vegetationsutveckling, sarskilt skogshistoria, i nordvastra Gotaland. (Zusarnmenfassung: Pollenanalytische Zeugnisse der spatquartaren V egetationsentwicklung, hauptsachlich der Waldgeschichte, im nordwestl ichen Gotaland, Si.idschweden.) ISBN 9 1 -72 1 0-029-X. Price: 240 SEK.

30. M. w�m. 1 952. Rocky-shore algae in the Oregrund Archipelago. ISBN 9 1 -72 1 0-030-3. Price: 290 SEK.

3 1 . 0. Rune. 1 953. Plant life on serpentines and related rocks in the North of Sweden. 1 953 . ISBN 9 1 -72 1 0-03 1 - 1 . Price: 240 SEK.

32. P. Kaaret. 1 953. Wasservegetation der Seen Orlangen und Trehomingen. ISBN 9 1 -72 1 0-032-X. Price: 1 60 SEK.

33. T. E. Hasselrot. 1 953. Nordliga lavar i Syd- och Mellansverige. (Nordliche Flechten in Si.id- und Mittelschweden.) ISBN 9 1 -72 1 0-033-8. Price: 240 SEK.

34. H. SjOrs. 1 954. S latterangar i Grangarde Finnrnark. (Summary: Meadows in Grangarde Finnrnark, SW Dalama, Sweden.) ISBN 9 1 -721 0-034-6. Price: 1 60 SEK.

35 . S. Kilander. 1 955. Karlvaxtemas ovre granser pa fjall i sydvastra Jamtland sarnt angransande delar av Harjedalen och Norge. (Summary: Upper limits of vascular plants on mountains in southwestern Jamtland and adjacent parts of Harjedalen (Sweden) and Norway.) ISBN 9 1 -72 1 0-035-4. Price: 240 SEK.

36. N. Quennerstedt. 1 955 . Diatomeema i Langans sjovegetation. (Summary: Diatoms in the lake vegetation of


the Langan drainage area, Jamtland, Sweden.) ISBN 9 1 -72 1 0-036-2. Price: 240 SEK.

37. M.-B. Florin. 1 957. Plankton of fresh and brackish waters in the Sodertalje area. ISBN 9 1 -72 1 0-037-0. Price : 1 60 SEK.

38. M.-B. Florin. 1 957. Insjostudier i Mellansverige. Mik:rovegetation och pollenregn i vikar av Ostersjobackenet och insjoar fran preboreal tid till nutid. (Summary: Lake studies in Central Sweden. Microvegetation and pol len rain in inlets of the Baltic basin and in lakes from Preboreal time to the present day.) 1 957. ISBN 9 1 -72 1 0-038-9. Price: 1 60 SEK.

39. M. Fries. 1 958. Vegetationsutveckling och odlingshistoria i V arnhemstrakten. En pollenanalytisk undersokning i Vastergotland. (Zusammenfassung: Vegetationsentwicklung und Siedlungsgeschichte im Gebiet von V arnhem. Eine pollenanalytische Untersuchung aus Vastergotland (Si.idschweden) . ) ISBN 9 1 -72 1 0-039-7 . Price: 1 60 SEK.

40. B. Pettersson. 1 958. Dynarnik och konstans i Gotlands flora och vegetation. (Zusarnrnenfassung: Dynarnik und Konstanz in der Flora und Vegetation von Gotland, Schweden.) ISBN 9 1 -72 1 0-040-0. Price: 400 SEK.

4 1 . E. Uggla. 1 958. Skogsbrandfalt i Muddus nationalpark. (Summary: Forest fue areas in Muddus National Park, northern Sweden.) ISBN 9 1 -72 1 0-04 1 -9. Price: 1 60 SEK.

42. K. Thomasson. 1 959. Nahuel Huapi. Plankton of some lakes in an Argentina National Park, with notes on terrestrial vegetation. ISBN 9 1 -72 1 0-042-7. Price: 1 60 SEK.

43. V. Gillner. 1 960. Vegetations- und Standortsuntersuchungen in den Strandwiesen der schwedischen Westktiste. ISBN 9 1 -72 1 0-043-5 . Price: 240 SEK.

44. E. Sjogren. 1 96 1 . Epiphytische Moosvegetation in Laubwaldem der Insel Oland, Schweden. (Summary: Epiphytic moss communities in deciduous woods on the island of Gland, Sweden.) ISBN 9 1 72 1 0-044-3 (ISBN 9 1 -72 1 0-444-9). Price: 1 60 SEK.

45 . G. Wistrand. 1 962. Studier i Pite Lappmarks karl vaxtflora, med sarskild hansyn till skogslandet och de isolerade fjallen. (Zusarnrnenfassung: Studien i.iber die Gefasspflanzenflora der Pite Lappmark mit besonderer Beri.icksichtigung des W aldlandes und der isolierten niederen Fjelde.) ISBN 9 1 -72 1 0-045- 1 (ISBN 9 1 -72 1 0-445-7). Price: 240 SEK.

46. R. lvarsson. 1 962. Lovvegetation i Mollosunds socken. (Zusarnmenfassung: Die Laubvegetation im Kirchspiel Mollosund, Bohuslan, Schweden.) ISBN 9 1 -72 1 0-046-X (ISBN 9 1 -72 1 0-446-5). Price: 1 60 SEK.

47. K. Thomasson. 1 963. Araucanian Lakes. Plankton studies in North Patagonia, with notes on terrestrial vegetation. ISBN 9 1 -72 1 0-047-8. Price: 240 SEK.

48. E. Sjogren . 1 964. Epilitische und epigaische Moosvegetation in Laubwaldem der Insel Gland, Schweden. (Summary: Epilithic and epigeic moss vegetation in deciduous woods on the island of Gland, Sweden.) ISBN 9 1 -72 1 0-048-6 (ISBN 9 1 -72 1 0-448- 1 ) . Price: 240 SEK.

49. 0. Hedberg. 1 964. Features of afroalpine plant ecology. (Resume fran�ais.) ISBN 9 1 -72 1 0-049-4 (ISBN 9 1 -72 1 0-449-X). Price: 240 SEK.

50. The Plant Cover of Sweden. A study dedicated to G. Einar Du Rietz on his 70th birthday by his pupils. 1 965 . ISBN 9 1 -72 1 0-050-8. Price: 4 1 1 2 SEK.

5 1 . T. Flensburg. 1 967. Desmids and other benthic algae of Lake Kavsjon and Store Mosse. SW Sweden. ISBN 9 1 -72 1 0-05 1 -6 (ISBN 9 1 -72 1 0-45 1 - 1 ). Price: 240 SEK.

52. E. Skye. 1 968. Lichens and air pollution. A study of cryptogamic epiphytes and environment in the Stockholm region. ISBN 9 1 -72 1 0-052-4 (ISBN 9 1 -72 1 0-452-X). Price: 240 SEK.

53. J. Lundqvist. 1 968. Plant cover and environment of steep hil lsides in Pite Lappmark. (Resume: La couverture vegetale et ! 'habitat des flancs escarpes des collines de Pite Lappmark. ) ISBN 9 1 -72 1 0-053-2 (ISBN 9 1 -72 1 0-453-8). Price: 240 SEK.

54. Conservation of Vegetation in Africa South of the Sahara. Proceedings of a symposium held at the 6th Plenary meeting ofthe AETFAT, Uppsala Sept. l 2- 1 6, 1 966. 1 968. ISBN 9 1 -72 1 0-054-0 (ISBN 9 1 -72 1 0-454-6). Price: 290 SEK.

55. L. -K. Konigsson. 1 968. The Holocene history of the Great Alvar of bland. ISBN 9 1 -72 1 0-055-9 (ISBN 9 1 -72 1 0-455-4). Price: 290 SEK.

56. H. P. Hallberg. 1 97 1 . Vegetation auf den Schalenablagerungen in Bohuslan, Schweden. (Summary: Vegetation on shell deposits in Bohuslan, Sweden.) ISBN 9 1 -72 1 0-056-7 (ISBN 9 1 -72 1 0-456-2). Price: 240 SEK.

57. S. Fransson. 1 972. Myrvegetation i sydvastra Varmland. (Summary: Mire vegetation in southwestern Vlirmland, Sweden.) ISBN 9 1 -72 1 0-057-5 (ISBN 9 1 -72 1 0-457-0). Price: 240 SEK.

58 . G. Wallin. 1 973 . Lovskogsvegetation i Sjuharadsbygden. (Summary: Deciduous woodlands in Sjuharadsbygden, Vastergotland, southwestern Sweden.) ISBN 9 1 -72 1 0-058-3 (ISBN 9 1 -72 1 0-458-9). Price: 240 SEK.

59. D. Johansson. 1 974. Ecology of vascular epiphytes in West African rain forest. (Resume: Ecologie des epiphytes vasculaires dans la foret dense humide d' Afrique occidentale.) ISBN 9 1 -72 1 0059- 1 (ISBN 9 1 -72 1 0-459-7). Price: 290 SEK.

60. H. Olsson. 1 974. Studies on South Swedish sand vegetation. ISBN 9 1 -72 1 0-060-5 (ISBN 9 1 -72 1 0-460-0). Price: 240 SEK.

6 1 . H. Hyttebom. 1 975. Deciduous woodland at Andersby, eastern Sweden. Above-ground tree and shrub production. ISBN 9 1 -72 1 0-06 1 -3 (ISBN 9 1 -72 1 0-46 1 -9). Price: 240 SEK.

62. H. Persson. 1 975. Deciduous woodland at Andersby, eastem Sweden. Field-layer and below-ground production. ISBN 9 1 -72 1 0-062- 1 (ISBN 9 1 -72 1 0-462-7) . Price: 1 60 SEK.

63. S. Brakenhielm. 1 977. Vegetation dynamics of afforested farmland in a district of south-eastern Sweden. ISBN 9 1 -72 1 0-063-X (ISBN 9 1 -72 1 0-463-5). Price: 240 SEK.

64. M. Y Ammar. 1 978. Vegetation and local environment on shore ridges at Vickleby, bland, Sweden. An analysis. ISBN 9 1 -72 1 0-064-8 (ISBN 9 1 -72 1 0-464-3) . Price: 240 SEK.

65. L. Kullman. 1 979. Change and stability in the altitude of the birch tree-limit in the southern Swedish Scandes 1 9 1 5-1 975. ISBN 9 1 -72 1 0-065-6 (ISBN 9 1 -72 1 0-465- 1 ) . Price: 240 SEK.

66. E. Waldemarson Jensen. 1 979. Successions in relationship to lagoon development in the Laitaure delta, North Sweden. ISBN 9 1 -72 1 0-066-4 (ISBN 9 1 -72 1 0-466-X). Price:

240 SEK.

Svenska Viixtgeografiska Siillskapet 63

67. S. Tuhkanen. 1 980. Climatic parameters and indices in plant geography. ISBN 9 1 -72 1 0-067-2 (ISBN 9 1 -72 1 0-467-8). Price: 240 SEK.

68. Studies in plant ecology dedicated to Hugo Sjors. E. Sjogren (ed.) 1 980. ISBN 9 1 -72 1 0-068-0 (ISBN 9 1 -72 1 0-468-6). Price: 290 SEK.

69. C. Nilsson . 1 98 1 . Dynamics of the shore vegetation of a North Swedish hydro-electric reservoir during a 5-year period. ISBN 9 1 -72 1 0-069-9 (ISBN 9 1 -72 1 0-469-4 ). Price: 240 SEK.

70. K. Warenberg. 1 982. Reindeer forage plants in the early grazing season. Growth and nutritional content in relation to climatic conditions. ISBN 9 1 -72 1 0-070-2 (ISBN 9 1 -72 1 0-470-8). Price: 240 SEK.

7 1 . C. Johansson. 1 982. Attached algal vegetation in running waters of Jamtland, Sweden. ISBN 9 1 72 1 0-07 1 -0 (ISBN 9 1 -72 1 0-47 1 -6). Price: 240 SEK.

72. E. Rosen. 1 982. Vegetation development and sheep grazing in limestone grasslands of South bland, Sweden. ISBN 9 1 -72 1 0-072-9 (ISBN 9 1 -72 1 0-472-4). Price: 290 SEK.

73. Zhang Liquan. 1 983. Vegetation ecology and population biology of Fritillaria meleagris L. at the Kungsangen Nature Reserve, eastern Sweden. ISBN 9 1 -72 1 0-073-7 (ISBN 9 1 -72 1 0-473-2). Price: 240 SEK.

74. I. Backeus. 1 985. Aboveground production and growth dynamics of vascular bog plants in central Sweden. ISBN 9 1 -72 1 0-074-5 (ISBN 9 1 -72 1 0-474-0). Price: 240 SEK.

75. E. Gunnlaugsd6ttir. 1 985. Composition and dynamical status of heathland communities in Iceland in relation to recovery measures. ISBN 9 1 -72 1 0-075-3 (ISBN 9 1 -72 1 0-475-9). Price: 240 SEK.

76. Plant cover on the limestone Alvar on bland. EcologySociology-Taxonomy. E. Sjogren (ed.) 1 988. ISBN 9 1 -72 1 0-076- 1 (ISBN 9 1 -72 1 0-476-7). Price: 320 SEK.

77. A. H. Bjamason. 1 99 1 . Vegetation on lava fields in the Hekla area, Iceland. ISBN 9 1 -72 1 0-077-X (ISBN 9 1 -72 1 0-477-6). Price: 290 SEK.

78. I. Wallentinus & P. Snoeijs (eds.). 1 992. Algological studies of Nordic coastal waters - A festschrift to Prof. Mats Wrem on his 80th birthday-. ISBN 9 1 -72 1 0-078-8 (ISBN 9 1 -72 1 0-478-3 ) . Price: 290 SEK.

79. Tamrat Bekele. 1 993. Vegetation ecology ofremnant Afromontane forests on the Central Plateau of Shewa, Ethiopia. ISBN 9 1 -72 1 0-079-6 (ISBN 9 1 -72 1 0-479- 1 ) . Price: 290 SEK.

80. M. Diekmann. 1 994. Deciduous forest vegetation in Boreonemoral Scandinavia. ISBN 9 1 -72 1 0-080-X (ISBN 9 1 -72 1 0-480-5). Price: 290 SEK.

8 1 . Plant root systems and natural vegetation. 1 996. H . Persson & I .O. Baitulin (eds .) ISBN 9 1 -72 1 0-08 1 -8 (ISBN 9 1 -72 1 0-08 1 -3) . Price: 290 SEK.

82. Middle oroarctic vegetation in Finland and middle-northem arctic vegetation on Svalbard 1 996. R. Virtanen & S. Eurola (eds.) ISBN 9 1 -72 1 0-082-6. (9 1 -72 1 0-482-5). Price: 290 SEK.

A limited number of cloth-bound copies of Acta 44, 45, 46, 48, 49, 5 1 , 52, 53, 56, 57, 6 1 , 63, 66, 67, 68, 69, 70, 7 1 , 72, 73, 74, 75, 76, 77, 78, 79, 80 and 81 is available at an additional cost of 75 SEK per volume. (Use ISBN n°S. within brackets to order.)


64 Svenska Viixtgeografiska Siillskapet

STUDIES IN PLANT ECOLOGY (VOL. 1 - 1 9)

1 . S. Brakenhielm & T Ingelog. 1 972. Vegetationen i Kungshamn-Morga naturreservat med forslag till skotselplan. (Summary: Vegetation and proposed management in the Kungshamn-Morga Nature Reserve south of Uppsala.) ISBN 9 1 -72 1 0-80 1 -0. Price: 1 1 2 SEK.

2. T. Ingelog & M. Risling. 1 973. Kronparken vid Uppsala, historik och bestandsanalys av en 300-ang tallskog. (Summary : Kronparken, history and analysis of a 300-year old pinewood near Uppsala, Sweden.) ISBN 9 1 -72 1 0-802-9. Price: 1 1 2 SEK.

3. H. Sjiirs et al. 1 973. Skyddsvarda myrar i Kopparbergs Hin. [Summary: Mires considered for protection in Kopparberg County (Prov. Dalama, Central Sweden.)] ISBN 9 1 -72 1 0-803-7. Price: 1 1 2 SEK.

4. L. Karlsson. 1 973. Autecology of cliff and scree plants in Sarek National Park, northern Sweden 1 973 . ISBN 9 1 -72 1 0-804-5. Price: 1 60 SEK.

5. B. Klasvik. 1 974. Computerized analysis of stream algae. ISBN 9 1 -72 1 0-805-3. Price: 1 1 2 SEK.

6. Y. Dahlstrom-Ekbohm. 1 975 . Svensk miljovards- och omgivningshygienlitteratur 1 952- 1 972. Bibliografi och analys. ISBN 9 1 -72 1 0-806- 1 . Price: 1 1 2 SEK.

7. L. Rodenborg. 1 976. Bodennutzung, Pflanzenwelt und ihre Verlinderungen in einem alten Weidegebiet auf Mittel-Oland, Schweden. ISBN 9 1 -72 1 0-807-X. Price: 1 1 2 SEK.

8. H. Sjors & Ch. Nilsson. 1 976. Vattenutbyggnadens effekter pa levande natur. En faktaredovisning overvagande fran Umealven. (Summary: B ioeffects of hydroelectric development. A case study based mainly on observations along the Ume River, northern Sweden.) ISBN 9 1 -72 1 0-808-8. Price: 1 60 SEK.

9. J. Lundqvist & G. Wistrand. 1 976. Strandflora inom ovre och mellersta Skelleftealvens vattensystem. Med en sammanfattning betraffande botaniska skyddsvarden. (Summary: Riverside vascular flora in the upper and middle catchment area of the River Skelleftealven, northern Sweden. ) ISBN 9 1 -72 1 0-809-6. Price: 1 1 2 SEK.

1 0. A. Mii.ller-Haeckel. 1 976. Migrationsperiodik einzelliger Algen in Fliessgewassern. ISBN 9 1 -72 1 0-8 1 0-X. Price: 1 1 2 SEK.

1 1 . A. Sjodin . 1 980. Index to distribution maps of bryophytes 1 887- 1 975. 1 . Musci. (hard-bound) . ISBN 9 1 -72 1 0-8 1 1 -8 . Price: 1 60 SEK.

1 2. A. S}Odin. 1 980. Index to distribution maps of bryophytes 1 887- 1 975. II. Hepaticae. (hard-bound) . ISBN 9 1 -72 1 0-8 1 2-6. Price: 1 1 2 SEK.

1 3 . 0. Eriksson, T Palo & L. Soderstrom. 1 98 1 . Renbetning vintertid. Undersokningar rorande svensk tarnrens naringsekologi under snoperioden. ISBN 9 1 -72 1 0-8 1 3 -4. Price: 1 1 2 SEK.

1 4. G. Wistrand. 1 98 1 . Bidrag till Pite lappmarks vaxtgeografi. ISBN 9 1 -72 1 0-8 14-2. Price: 1 1 2 SEK.

1 5 . T. Karlsson. 1 982. Euphrasia rostkoviana i Sverige. ISBN 9 1 -72 1 0-8 1 5-0. Price: 1 60 SEK.

1 6. Theory and Models in Vegetation Science: Abstracts. ISBN 9 1 -72 1 0-8 1 6-9. 1 985. Price: 1 60 SEK.

1 7 . /. Backeus. 1 988. Mires in the Thaba-Putsoa Range of the Maloti, Lesotho. ISBN 9 1 -72 1 0-8 1 7-7. Price: 1 60 SEK.

1 8 . Forests of the world - diversity and dynamics (Abstracts) 1 989. (Ed. E. Sjogren) ISBN 9 1 -72 1 0-8 1 8-5 . Price: 290 SEK.

1 9. E. Sjogren. 1 994. Changes in the epilithic and epiphytic moss cover in two deciduous forest areas on the island of bland (Sweden) . - A comparison between 1 958- 1 962 and 1988- 1 990. ISBN 9 1 -72 1 0-8 1 9-3. Price: 200 SEK.

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Middle oroarctic vegetation in Finland and middle-northern ...565361/FULLTEXT01.pdf · Middle oroarctic vegetation in Finland and middle-northern arctic vegetation on Svalbard 7 The