long-term changes in mediterranean vegetation in israel and california yohay carmel faculty of...
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Long-term changes in Mediterranean vegetation in Israel and California
Yohay CarmelYohay Carmel
Faculty of Agricultural EngineeringFaculty of Agricultural Engineering
The Technion -- Israel Institute of TechnologyThe Technion -- Israel Institute of Technology
Curtis FlatherCurtis Flather, Rocky Mountain Research Center, USDA Forest Service
Denis DeanDenis Dean, Department of Forest Sciences,Colorado State University
Ronen KadmonRonen Kadmon, Department of Ecology,
The Hebrew University of Jerusalem
A Cooperative Research:A Cooperative Research:
The Israel Forest Authority (KKL)
USDA Forest Service International Programs
Earlier stages of recovery following land abandonment: dwarf shrubs, tall shrubs, and low trees in Mt. Meron
Factors that potentially Factors that potentially affect affect
current vegetation patterncurrent vegetation patternPast vegetation:Percentage cover of Trees, Shrubs, Herbaceous vegetation
•Disturbance Agents:•Grazing•Logging•Fire
Topography:• Slope• Aspect• Elevation
Soil
Map of the study area in Mt. Meron, showing the distinct plots of different grazing pressure, and the range of fire
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No grazing Low Moderate High
NoGrazing
Cattle
Goats
Change in Trees as a function of Grazing Pressure
Ch
ang
e in
tre
e co
ver
± S
EC
han
ge
in t
ree
cove
r ±
SE
Regression results Regression results for thefor the linear models linear models 11
NS - not significant * p<0.05 ** p<0.01 *** p<0.001
GROUP VARIABLE HERBACEOUS TREES
R2 = 0.54 R2 = 0.76
Constant 0.373* 1.127***
Disturbance MODCATTLE 0.066* -0.502*
HIGHCATTLE NS -0.496*
LOWGOAT NS NS
MODGOAT 0.302* -0.483*
LOGGING NS -0.357***
Regression results Regression results forfor thethe linear models linear models 22
NS - not significant * p<0.05 ** p<0.01 *** p<0.001
Group Variable Herbaceous Trees
1964 HERB64 NS -0.457**
Vegetation (HERB64)2 0.506** -0.388**
Topography ASPECT-NS 0.0015* NS
Variables ASPECT-EW -0.0015*** 0.003***
SLOPE NS 1.062**
ASPECT-NS*SLOPE -0.0034* -0.011**
Model input (1964 vegetation)Model input (1964 vegetation)
Actual 1992 vegetationActual 1992 vegetation
Predicted 1992 vegetationPredicted 1992 vegetation(Linear model)(Linear model)
MODELS AND REALIZATIONSMODELS AND REALIZATIONS
DETERMINISTIC REALIZATION
STOCHASTIC REALIZATION
WITH AUTOCOVARIATES
NO AUTOCOVARIATES
COMPLETE DATASET
SAMPLE DATASET
LOGISTIC MODEL
LINEAR MODEL
DeterministiDeterministic c
RealizationRealization
31%45%
24%
StochastiStochastic c
RealizatioRealizationn
????
??
!!
Actual and predictedproportions of 1992 vegetation
Actualvegetation
map
Deterministicrealization
Stochasticrealization
Trees 0.51 0.44 0.50
Shrubs 0.32 0.41 0.33
Herbs 0.17 0.15 0.16
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LIN/DET LOG/DET LOG/STOC
Model Area External Area
Matching the actual map on a cell by cell basis
Grazing intensitiesGrazing intensities do not changedo not change Grazing is excludedGrazing is excluded
Scenarios for 2020
Precipitation patterns in California and Israel
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JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC
Pre
cipi
tati
on in
inch
es
ISR (Mt. Meron)
North CA (Cloverdale)
Central CA (Cachuma lake)
South CA (Cuyamaca)
Best match
Worst match
Precipitation match with Mt. Meron on a monthly basis
1. Cuyamaca mountains 2. Santa Ynez Mountains 4. Sequoia National Forest 5. Sierra Foothills Research Center 6. Hastings Natural History Reservation 8. South Cow Mountain
0%
1%
2%
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4%
All Withinreserve
Northslopes
Southslopes
Fire Initialtree
cover <0.1
An
nu
al r
ate
of
chan
ge
in t
ree
co
ve
r Hastings
Meron
Change in tree cover in Meron and Hastings
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Multipleregression
Pastvegetation
Topography Grazing, fire
HastingsMeron
Weight of predictors in affecting vegetation change
Mediterranean vegetation change in long-term, landscape-scale studies
0%
1%
2%
Ave
rage
an
nual
cha
nge
Why is there such a difference between vegetation dynamics
in California and the Mediterranean basin?
1. Local ecological and
anthropogenic conditions
2. Different soils
3. Different evolutionary historyDifferent evolutionary history
A transplant experiment is currently conducted, where oaks from both countries are grown
together in both sites, in a controlled environment
Carmel, Y. and Flather, C.H. 2004. Comparing landscape scale vegetation dynamics following recent disturbance in climatically similar sites in California and the Mediterranean basin. Landscape Ecology 19:573-590.
Carmel, Y., Kadmon R. and Nirel, R. 2001. Spatio-temporal predictive models of Mediterranean vegetation dynamics. Ecological Applications, 11 (1):268-280.
Carmel, Y. and Kadmon, R. 1999. Grazing, topography, and long term vegetation changes in a Mediterranean ecosystem. Plant Ecology, 145:239-250.
Carmel, Y. and Kadmon, R. 1998. Computerized classification of Mediterranean vegetation using panchromatic aerial photographs. Journal of Vegetation Science, 9:445-454.
Grunzweig, J.M., Carmel, Y., Riov, J. and Flather, C.H. Resource storage and adaptation to drought in oak seedlings: a comparative study with Californian and Mediterranean species. Submitted to Ecology.
More information on the various topics discussed here can be found in: