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GRADIENT:Himalayan elevation gradient NICHE: temperature niches Richness Endemics Life forms. But first: do communities exist?. A short answer after a long debate: No. Compositional variation in nature tends to be gradual. How can we analyse species composition?. - PowerPoint PPT Presentation
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GRADIENT: Himalayan elevation gradient
NICHE: temperature niches
Richness
Endemics
Life forms
But first: do communities exist?
A short answer after a long debate: No.
Compositional variation in nature tends to be gradual.
How can we analyse species composition?
Pinus Tsuga
Site 1 3 10
Site 2 5 1
Site 3 0 2
Site 4 4 8
Site 5 3 5
....... .... ....
Within some defined environment or area we sample a number of plots and register the species present
The temperature niche
Habitat is where plant live, e.g. in oak forest, on open slopes, at
rhododendron trees, etc
Distribution range is where on a geogrphical one may find the
target species
Elevation gradient variation in temperature and correlated variables e.g. soil
MontaneMontaneConiferouConiferou
ssForestForest
DeciduousDeciduousForestForest
AlpineAlpineTundraTundra
Temperated ForestTemperated Forest Northern Coniferous Northern Coniferous ForestForest
Arctic TundraArctic Tundra
lowlow
highhigh
Elevation
Elevation
elevation
Me
an
an
nu
al T
em
pe
ratu
re
0 1000 2000 3000 4000
51
01
52
02
5
elevation
Me
an
an
nu
al T
em
pe
ratu
re
0 1000 2000 3000 4000
51
01
52
02
5
Laps rate = 0.55 oC pr 100 elevation-meter
ELEVATION GRADIENT SPCECIES OCCURE AND DISAPEAR
Low-land spMid elevation
High-land sp
M ASL
ELEVATIONE RANGEELEVATION CONVERTED TO
TEMPERATURE
EXAMPLES:RHODODENDRON IN THE HIMALAYAS
Milke Danda
1000 masl Elevation range of Rh. Arboreum 3600 masl
Concepts: realized and potential niche
Realized climate niche = the average climate conditions where the species are growing in nature
Potential climate niche = the climate conditions where the (fundamental) species are able to grow without
interference from other organisms
temperature
abundance
Elevation gradient in temperature lapse rate= decrease 0.5 degrees Celsius each 100 elevation meter
MontaneMontaneConiferouConiferou
ssForestForest
DeciduousDeciduousForestForest
AlpineAlpineTundraTundra
Subtropical ForestSubtropical Forest NorthernNorthern Arctic TundraArctic Tundra
lowlow
highhigh
Elevation
Elevation
elevationM
ean
annu
al T
empe
ratu
re
0 1000 2000 3000 4000
510
1520
25
species 100 200 300 400 500 …. 6000
sp1 0 0 1 1 0 0
sp2 1 1 1 1 1 0
sp3 0 0 0 1 1 0
sp n-1 0 0 0 0 1 0
sp n 0 0 0 0 0 0
sum of spp 1 1 2 3 3 0
INTERPOLATION : ASSUMING ALL SPECIES ARE PRESNET IN ALL 100M INTERVALS BETWEEN LOWER AND UPPER ELEVATION LIMIT
This gives total number of specie in all different elevation bands from 100 m to 6000 m a.s.l.
INTERPOLATION : ASSUMING ALL SPECIES ARE PRESNET IN ALL 100M INTERVALS BETWEEN LOWER AND UPPER ELEVATION LIMIT
This gives total number of species in all different elevation bands from 100 m to 6000 m a.s.l.
This can be done for different life forms, such as ferns,trees or total number of endemics and total number of species
Tree species richness patterns
• Unimodal relationship between tree species richness and elevation.
• Maximum tree species found between 900 and 1000 m.
Elevation
Sp
ecie
s r
ich
ne
ss
0 1000 2000 3000 4000
05
01
00
15
02
00
Elevation
Spe
cies
ric
hnes
s
Mountain BiomesMountain Biomes
“Islands” = isolation= speciation, polyploidy => endemics
“Islands” = isolation= speciation, polyploidy => endemics
Internpolated species richness in the Himalayas
eleva
spp
no
0 1000 2000 3000 4000 5000 6000
02
00
40
06
00
80
01
00
01
20
0
Interpolated species richness in the Himalayas
eleva
spp
no
0 1000 2000 3000 4000 5000 6000
02
00
40
06
00
80
01
00
01
20
0
Plateau
MASL
1500 200 m asl
Is Gamma diversity able to predict the pattern of
Alpha diversity along an elevation range?
Ole R. Vetaas, M. Panthi, & K. Shrestha, IE Maaren
Centre for Development Studies, University of Bergen, Nygaardsgt. 5, N-5015 Bergen, NORWAY.
Central Department of Botany, Tribhuvan University, P.B. 5927 Kathmandu, Nepal.
Elevation Gradient
ConiferousConiferousForestForest
DeciduousDeciduousForestForest
Ice & rockIce & rockAlpineAlpine
TundraTundra
TROPICAL TROPICAL FORESTFOREST
EVERGREENEVERGREENOAK-RHODODENDRON-ForestOAK-RHODODENDRON-Forest
MontaneMontaneBETULABETULA
&…… &……
elevation gradient
ConiferousConiferousForestForest
DeciduousDeciduousForestForest
Ice & rockIce & rockAlpineAlpine
TundraTundra
TROPICAL TROPICAL FORESTFOREST
EVERGREENEVERGREENOAK-RHODODENDRON-ForestOAK-RHODODENDRON-Forest
MontaneMontaneBETULABETULA
&…… &……
2000 m asl
4000 m asl
elevation gradient
ConiferousConiferousForestForest
DeciduousDeciduousForestForest
Ice & rockIce & rockAlpineAlpine
TundraTundra
TROPICAL TROPICAL FORESTFOREST
EVERGREENEVERGREENOAK-RHODODENDRON-ForestOAK-RHODODENDRON-Forest
MontaneMontaneBETULABETULA
&…… &……
Rh. arboreum spp. arboreum
Rh. arboreum spp. cinnamomeum
elevation gradient
ConiferousConiferousForestForest
DeciduousDeciduousForestForest
Ice & rockIce & rockAlpineAlpine
TundraTundra
TROPICAL TROPICAL FORESTFOREST
EVERGREENEVERGREENOAK-RHODODENDRON-ForestOAK-RHODODENDRON-Forest
MontaneMontaneBETULABETULA
&…… &……
Area: Manag 3200 – 4000 maslSampling: 5 plots (10m x10m) in each 100m elevation on N- and S- aspects of the valley
elevation gradient
ConiferousConiferousForestForest
DeciduousDeciduousForestForest
Ice & rockIce & rockAlpineAlpine
TundraTundra
TROPICAL TROPICAL FORESTFOREST
EVERGREENEVERGREENOAK-RHODODENDRON-ForestOAK-RHODODENDRON-Forest
MontaneMontaneBETULABETULA
&…… &……
BETULA
Dry inner valleys
ANNAPURNA RANGE
MONSOON
Dry south-exposed slopes
Alpine shrub at 3800+ masl
Diversity concepts
• Two of late R.H. Whittakers diversity concepts
• Alpha diversity number of species in community, i.e. # species per area
• (point-alpha)
• Gamma diversity not well-defined concept, high alpha and high beta produce high gamma.
• Gamma diversity?
• Lomolino defined Gamma diversity as total number of species in certain elevations zone in a mountain range.
• Similar to the concept of Species pool, which is indicating the potential number of species that could be found in a given area.
Interpolated species richness in the Himalayas
eleva
sppn
o
0 1000 2000 3000 4000 5000 6000
020
040
060
080
010
0012
00
MASL
We used data on elevation ranges in the Enumeration of flowering plants in Nepal (Hara et al., 1978;Hara & Williams,1979; Hara et al., 1982) to describe the pattern of species richness along the elevation gradient.
GAMMA diversity~ species pool
Interpolated species richness in the Himalayas
eleva
spp
no
0 1000 2000 3000 4000 5000 6000
02
00
40
06
00
80
01
00
01
20
0
Plateau
MASL
LOCATION OF THE PLOTS
Alpha diversity number of species per 100 square metre
• Species richness was recorded from
350 10m x 10m plots: 2000 - 4000 m asl
Average species richness (alpha diversity)
for each 100 m elevation zone
Sources: Vetaas, Maaren, KB Shrestah, M Panthi, and
Ohasi H. (The Flora of eastern Himalaya)
Species pool for each 100m elevation interval = Gamma diversity
Elevation
Tota
l nu
mb
er
of
spe
cie
s a
t e
ach
10
0m
ele
vatio
n r
an
ge
2000 2500 3000 3500 4000
95
01
00
01
05
011
00
115
01
20
0
Average alpha diversity in 100 square metre plots for each 100m elevation interval
Elevation
Me
an
nu
mb
er
of
spe
cie
s p
r 1
00
m-2
2000 2500 3000 3500 4000
10
20
30
40
41% Deviance explained
38% Deviance explained
Gamma diversity at each 100m elevation range
Alp
ha
div
ers
ity a
t e
ach
10
0m
ele
vatio
n r
an
ge
950 1000 1050 1100 1150 1200
10
20
30
40
Gamma diversity at each 100m elevation range
Alp
ha
div
ers
ity a
t e
ach
10
0m
ele
vatio
n r
an
ge
10.5 11.0 11.5 12.0 12.5 13.0
2.5
3.0
3.5
• There is a significant drop in richness from the evergreen oak forest and deciduous forest at 2500 m asl to the marginal boreal zone with dominance of coniferous trees.
• This appear both in gamma level and alpha level
• Thus the gamma level can predict the alpha level, at least the pattern of change
The plateau ?
• Gamma diversity also indicate a plateau
• This is found in alpha level
• But
• Tree species gamma does not predict this
• Herbaceous species gamma does!
Tree species richness patterns
• Unimodal relationship between tree species richness and elevation.
• Maximum tree species found between 900 and 1000 m.
• No plateau in
3000 – 4000 m asl.
Dispersal of herbaceous species
Elevation
Sp
ecie
s r
ich
ne
ss
0 1000 2000 3000 4000
05
01
00
15
02
00
Elevation
Spe
cies
ric
hnes
s
Elevation
Tota
l nu
mb
er
of
he
rba
ceo
us
spe
cie
s a
t e
ach
10
0m
ele
vatio
n r
an
ge
2000 2500 3000 3500 4000
95
01
00
01
05
011
00
115
01
20
0
Herbaceous gamma explain 22 % of the deviance in total Alpha
Herbaceous Gamma diversity at each 100m elevation range
Me
an
alp
ha
div
ers
ity a
t e
ach
10
0m
ele
vatio
n r
an
ge
950 1000 1050
10
20
30
40
What cause these patterns?
• Drop in richness
• Increased change in temperature
Laps rate break!
Temperature decreases at a fasterrate above 3000 m
U-valley with glaciers
elevation
Me
an
an
nu
al T
em
pe
ratu
re
0 1000 2000 3000 4000
51
01
52
02
5
9 of 12 points are colder than laps rate estimate
Dry south-exposed slopes
PLATEAUGeology : U-valleyDomestic animals seed dispersal
CONCLUSIONS
• Gamma diversity estimates are useful to detect pattern and deduce hypothesis that can be tested by field sampling
• Example here:• The drop in richness form evergreen forest to
‘boreal’ sub-alpine coniferous forest• Plateau in richness in the coniferous dominated
U-valley of the arid central Himalayas.
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