Changes in the ground vegetation composition of forest ecosystems observed in the Czech Republic ( in relation to atmospheric depositions, soil properties, temperatures and precipitation amounts )

Introduction

The aim of the elaboration is to compare nitrogen atmospheric deposition to biodiversity in eight forest plots of the intensive monitoring (level II) included to the International Cooperative Programme for Forests (Fig. 1). They are Mísečky, Želivka, Lásenice, Všeteč, Lazy, Luisino údolí, Medlovice, and Březka. Monitoring of forest plots operated by the Forestry and Game Management Research Institute has been giving the data on forest environmental properties since 1994 (Boháčová et al., 2010). The evaluation of relationships between nitrogen depositions and biodiversity are partial results of the grant Forest soil state as a determining factor of health state development, biodiversity and filling productivity and outside productivity functions of forests solved under the sponsorship of the Ministry of Agriculture of the Czech Republic (Novotný et al., 2013). Atmospheric sulphur, oxidized and reduced nitrogen depositions, meteorological characteristics and soil properties, including soil solution chemistry are related to the forest ground vegetation (herbal floor). The data incorporated in the elaboration were prepared for the last Call for Data 2013/2014 and processed with the use of measurement data, above all.

Irena Skořepová 1, Václav Buriánek 2, Jaroslav Skořepa 5, Zora Lachmanová 2, Vít Šrámek 2, Radek Novotný 2, Monika Vejpustková 2,

Kateřina Neubertová Hellebrandová 2, Iva Hůnová 3 , Miloš Zapletal 4

24rd CCE Workshop and 30th Task Force Meeting of the ICP Modelling and Mapping, 7 – 10 April 2014, Rome, Italy

1 Czech Geological Survey, 2 Forestry and Game Management Research Institute, 3 Czech Hydrometeorological Institute,

4 Centre for Environment and Land Assessment - Ekotoxa, s.r.o., 5 private person

The state of ground vegetation is assessed using semi-quantitative method of phytocenological snaps. Assessment in each plot is done since 2004, at the sub-plot of 400 m2, situated at the centre of the plot. Eight-member, modified, combined scale of abundance and dominance, by Braun-Blanquet (1965) is used. Presence of all vegetation species in herb layers (used in this evaluation) was registered, coverage or number respective was visually estimated and classified within the following scale:

r: very rare species, mostly only one or few individuals of negligible coverage+: rare species (at least two individuals in the plot) or few individuals of low coverage1: frequent species, but of low coverage, or less frequent of more dense coverage, 5 % maximally (often individual bushes or rarer grasses)2a: very frequent species (abundant) high numer of small individuals of about 5 % coverage, or lower number of bigger plants of 5 -12.5 % coverage2b: same as 2a. Coverage always 12.5-25% of total area3: species of coverage 25-50%4: species ofcoverage 50-75%5: species of coverage 75-100%These items are considered according to coverage of individual species with the average value in the given range in the elaborated graphs. Items indicating very rare and rare species are interpreted as 0.1% and 0.5% coverage, respectively.

References

Boháčová, L., Lomský, B., Šrámek, V. (eds) (2010): Monitoring zdravotního stavu lesa v České republice. Ročenka programu ICP Forests/FutMon data 2008 a 2009. Forest Condition Monitoring in the Czech Republic. Annual Report ICP Forests/FutMon Programme data 2008 and 2009. VÚLHM, 160 pp.

Braun-Blanquet, J. (1965): Plant Sociology, the Study of Plant Communities. London, Hafner. p. 439.

Chytrý, M., Kučera, T., Kočí, M., eds. (2001): Katalog biotopů České republiky. Interpretační příručka k evropským programům Natura2000 a Smaragd. AOPK, Praha ve spolupráci s PřFMU, Brno a BÚ AVČR. ISBN 80-86064-55-7, 1. vydání, Praha. 307 pp.

Clarke N, Zlindra D, Ulrich E, Mosello R, Derome J, Derome K, König N, Lövblad G, Draaijers GPJ, Hansen K, Thimonier A, Waldner P, 2010: Sampling and Analysis of Deposition. 66 pp. Part XIV. In: Manual on methods and criteria for harmonized sampling, assessment, monitoring and analysis of the effects of air pollution on forests. UNECE, ICP Forests, Hamburg. ISBN: 978-3-926301-03-1. [http://www.icp-forests.org/Manual.htm]

Draaijers, G. P. J & Erisman, J. W., Van Leeuwen, N. F. M., Römer, F. G., Te Winkel, B. H., Vermeulen, A. T., Wyers, G. P. & Hansen, K. (1995): The contribution of canopy exchange to differences observed between atmospheric deposition and throughfall fluxes. In: Studies in Environmental Sciences 64 : p. 455-456.

Draaijers G.P.J., Erisman J.W., Lövblad G., Spranger T., Vel E. (1998): Quality and uncertainty aspects of forest deposition estimation using throughfall, stemflow and precipitation measurements. TNO-Report TNO-MEP-R 98/093, TNO, The Netherlands, 73 pp.

Novotný, R., Hůnová, I., Skořepová, I., Zapletal, M., Seidl, V., Buriánek, V., Fadrhonsová, V., Jurkovská, L., Neudertová Hellebrandová, K., Kurfűrst, P., Lachmanová, Z., Ostatnická, J., Schovánková, J., Schreiberová, M., Stoklasová P., Šrámek, V., Vlček, O. (2013): Stav lesních půd jako určující faktor vývoje zdravotního stavu, biodiverzity a naplňování produkčních i mimoprodukčních funkcí lesa Závěrečná zpráva grantu NAZV QI112A168, Výzkumný ústav lesního hospodářství a myslivosti, Zbraslav - Strnady. 65 pp. (Forest soil state as a determining factor of health state development, biodiversity and filling productivity and outside productivity functions of forests. Final Report of the NAZV grant, Forestry and Game Management Research Institute, Zbraslav – Strnady. 65 pp.).

Results

Most of the data were compiled for the years of the phenological survey i.e. 2005 and 2009. Atmospheric depositions of sulphur and nitrogen for the given years were calculated from the measured data on the average annual throughfall, bulk and wet depositions. In addition to the data on atmospheric depositions, some measured parameters of soil properties and the soil solution of the soil horizon to a depth of 40 cm and the upper soil horizon to a depth of 10 cm, respectively, were also calculated. The forest ground vegetation with the most abundant vegetation types is represented by the herb layer.

Methodology

Forests of the Czech Republic, characterized by selected plots according to typological classification, fall into four forest habitats. These are mostly beach wood forests characterized by the class to L5.4 of the Catalogue (Chytrý et al., 2001), which comprises mountain acidophilous spruce-beech woodland, Callamagrostio-villosae ass. (Mi), acid oak-beech woodland with Deschampsia flexuosa (Ze), fresh beech woodland with Galium odoratum (Vse), acid fir-beech woodland of Deschampsio-flexuosae-Abietinum ass. (Las). This habitat can be summarized in EUNIS classification G.1.7 as Medio-European acidophilous beech forests. Acid beech-oak woodland with Carex sp. (Bre) and fresh beech-oak forest with Luzula luzuloides and Galium odoratum characterized by classes to L 7.1 and L 6.4, respectively, can be compared with category G.1.8 Medio-European acidophilous oak forests. Other category consists of climax spruce stands with beech and maple admixture (L 9.1) and can be classified into the EUNIS system as G 3.2 Hercynian subalpine spruce forests (Lu). The transfer of typology of forests to EUNIS classes was carried out according to the above-mentioned catalogue (Chytrý et al., 2001).

Fig. 4 Critical loads and exceedances of sulphur and nitrogen for the plot Želivka in 1996, 2000, 2005 and 2009

Fig. 1 Location of forest plots included in the Call for Data 2013/2014 (blue and green background areas in the figure belong to the Nature 2000 and national protected areas, respectively, The Agency of Nature and Landscape Protection, 2013)

Fig. 3 A number of ground vegetation species in the relation to nitrogen atmospheric depositions in the forest plot Želivka in 1996-2009

The herb layer includes species sensitive to nitrogen as well as nitrophilous species. Some herbs are present only on a few less monitored plots and there is either a relatively small number of values for the evaluation or the species occur only sporadically. The maximum occurrence of herb species of vegetation (25-31) can be seen in the forest plot Všeteč with nitrogen atmospheric deposition of cca 1280 eq ha-1 per year. Forest plots Želivka and Březka also show the high occurence of vegetation species. Number of them was in the range from 22 to 26 in the period of 2005-2009 with atmospheric depositions of nitrogen in the range of approximately 980-1230 eq ha-1y-1. On the contrary the lowest number of ground vegetation species (7 species) has been observed in the plot Lásenice with nitrogen atmospheric depositions between 1170-1250 eq ha-1y-1. This site is typical by sandy loam soils and dune sands in the background. Ground vegetation species seem to be without response to atmospheric deposition (both nitrogen and sulphur).

The relationship of total nitrogen depositions and total species coverage shows vegetation coverage increases with an increase in atmospheric deposition of nitrogen (Fig. 2). Therefore, it is needed to include the influence of the site environment to dose-response relationships, as well. When we selected one site with relatively long time series of measurements such as Želivka, for example, we obtained decreases in number vegetation species in this site with an increase in nitrogen atmospheric deposition (Fig. 3). The main characteristics of the site are critical loads of sulphur and nitrogen based on environmental properties. Exceedances of critical loads should influence the composition of vegetation species. Exceedances of critical loads in the case of the forest plot Želivka are shown in the Fig. 4. For comparison the atmospheric deposition of nitrogen for the given years (2005 and 2009) was calculated from the measured data on the average annual canopy deposition of nitrogen accumulated 3 to 5 years (depending on data availability) before the examination (Fig. 5).

Conclusions

There are an insufficient number of values to evaluate the extent of atmospheric deposition of nitrogen levels exactly. Relatively short time series of measurements and uncertainties in actual total nitrogen atmospheric depositions create many obstacles in correct assessments. Biodiversity observations fall in the period of relatively small gradient in atmospheric depositions of nitrogen and sulphur. The influence of delay in atmospheric deposition effects to ground vegetation species has not been involved in the evaluation in the Call for Data 2013/2014.

Table 1 presents the main characteristics of examined forest plots such as soil types and textures, background rocks, the main tree species and their average annual growth. The soil texture responds to the soil layer of 40 centimetres from the top. Annual growth of trees presents wood increments (in dry mass) calculated on the base of tree height and thickness measurements (thickness of trees must be higher than 7 centimetres). Tree growth monitoring has been realized in five years intervals since 1999 (Mísečky, Želivka, Březka, Lazy) or 2004 (Všeteč, Lásenice, Luisino údolí, Medlovice).

Site Name TreesAnnual average

growthin kg ha-1 a-1

 Background rocks Soil type 

Soil texture  

2015 Mísečky Beech, spruce 1693.43 Biotic slate Podzols Sandy loam

2161 Želivka Spruce 3776.31 Paragneiss Cambisols Loam

2102 BřezkaOak and other deciduous

5254.66Biotic granodiorite

with amphibolCambisols Loam

2103 Všeteč Beech 9506.05 Biotic paragneiss Cambisols Sandy loam

2163 Lásenice Spruce, beech, fir 6818.22 Dune sands Podzols Loamy sand

2251 Luisino údoli Spruce 3716.73 Gneiss-migmatite Podzols Sandy loam

2361 MedloviceBeech, oak, pine, larch

6542.20Claystone to

sandstone glauconic rocks

Cambisols Sandy loam

2521 Lazy Spruce 4034.95Coarse-grained biotitic granite

Podzols Sandy loam

Table 1: Site characteristics of forest plots

Most of the data was acquired on a monthly basis by a uniform methodology (Clarke et al., 2010). The data on precipitation amounts, temperature and radiation were taken from continuous measurements. Their daily data were used and processed by the MetHyd model. Soil properties such as the texture and basic chemical compositions were measured in 2006. Soil characteristics represent the soil layer of 40 centimetres measured from the top. The data on slopes, aspects and altitudes were taken from the geographical map. Information on the values of “TempC” and “Theta” represent the annual averages of daily measurements in the period of 2005 – 2010. Parameters such as concentrations of nitrogen, base cations, pH and alkality in the soil solution are observed in samples collected under the soil organic layer in the given year. Values of C pool, CNrat, bsat and Qle evaluate the top soil layer up to depth of 10 cm.

y = 0,0541x - 47,184R² = 0,5644

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BIODIVINDEX

N dep eq ha-1 a-1

% of coverage

Data on deposition measurements used for the elaboration were assessed on the base of bulk and throughfall samples and their analyses. Throughfall and bulk depositions have measured since 1996 (1997) in four plots (Mísečky, Želivka, Medlovice and Lazy). The forest plot Březka has provided deposition data from 2000. Another forest plots have begun to monitor in 2003 or latter (Luisino údolí in 2004). Stemflow samples have been collected from the plots of deciduous forests - in Medlovice, Všeteč, and Mísečky. Procedures for measurements in the forest plots are comparable with other deposition measurements within ICP Forests and UN-ECE programmes. Total depositions for the forest ecosystem were calculated according to the methodology published in Draaijers et al. (1995, 1998). Total depositions of reduced nitrogen forms contain modelled dry depositions of gaseous form of ammonia (Zapletal, 2013: In Novotný et al., 2013).

Biodiversity observations in forest plots were realised in 2005 and 2009 in most cases. Some of phytocenological snaps from localities have been carried out earlier. For example, four sets of forest vegetation species snaps are available in the experimental plot Medlovice (1998, 2001, 2005, and 2009). Similarly, biodiversity data were compiled for the years 1996, 2000, 2005 and 2009 in the forest plot Želivka. Percentages of ground vegetation species coverage in the forest plots only represent herbs (herb forest layer).

Fig. 2 Relationships between nitrogen atmospheric depositions and total coverage by ground vegetation species in the herb layer of forests (the item BIODIVINDEX in the table “DRpoint”)

1996

The coverage of some vegetation types of the herb layer dramatically decreases with increasing atmospheric deposition of nitrogen with use of accumulated nitrogen depositions ( from 3 – 5 years before). The largest coverage of blueberries (Vaccinium myrtillus) and young shoots of European beech (Fagus sylvatica juv) occurs when the atmospheric deposition is in the range from approximately 9 to 13.5 kg N ha-1 per year-1. For common bent grass (Agrostis capillaris) and young spruce ash trees (Fraxinus excelsior juv.) the maximum coverage is bound to lower levels of atmospheric deposition equal to approximately 8.5 kg N ha-1 per year-1. There are an insufficient number of values to evaluate the extent of atmospheric deposition of nitrogen levels correctly.

Fig. 5 Relationship between atmospheric deposition of nitrogen and percentage cover of the herb layer of vegetation types Vaccinium myrtillus, Fagus sylvatica juv., Agrostis capillaris and Fraxinus excelsior juv.