957c27fcae6f46261af2a8364fe3d666.ppt
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Long-term changes in Mediterranean vegetation in Israel and California Yohay Carmel Faculty of Agricultural Engineering The Technion -- Israel Institute of Technology
A Cooperative Research: USDA Forest Service International Programs The Israel Forest Authority (KKL) Curtis Flather, Ronen Kadmon, Rocky Mountain Research Center, USDA Forest Service Department of Ecology, The Hebrew University of Jerusalem Denis Dean, Department of Forest Sciences, Colorado State University
Adult oaks (Quercus calliprinos) in Mt. Meron
Herbaceous vegetation in the front, recovering trees in the back, Mt. Meron
Earlier stages of recovery following land abandonment: dwarf shrubs, tall shrubs, and low trees in Mt. Meron
30 years after abandonment of pastoral cultivation in Mt. Meron
Mt. Meron 1945
Mt. Meron 1964
Mt. Meron 1992
Vegetation maps of Mt. Meron, Israel Herbaceous Vegetation Shrubs Trees
Factors that potentially affect current vegetation pattern Past vegetation: Topography: Percentage cover of Trees, Shrubs, Herbaceous vegetation • Slope • Aspect • Elevation • Disturbance Agents: • Grazing • Logging • Fire Soil
Map of the study area in Mt. Meron, showing the distinct plots of different grazing pressure, and the range of fire
Change in tree cover ± SE Change in Trees as a function of Grazing Pressure
Regression results for the linear models 1 NS - not significant * p<0. 05 ** p<0. 01 *** p<0. 001
Regression results for the linear models 2 NS - not significant * p<0. 05 ** p<0. 01 *** p<0. 001
Weight of predictors in affecting vegetation change in Mt. Meron
Model input (1964 vegetation) Actual 1992 vegetation Predicted 1992 vegetation (Linear model)
MODELS AND REALIZATIONS LINEAR MODEL LOGISTIC MODEL SAMPLE DATASET COMPLETE DATASET STOCHASTIC REALIZATION WITH AUTOCOVARIATES DETERMINISTIC REALIZATION NO AUTOCOVARIATES
Deterministic Realization Stochastic Realization ? ! ? ?
Stochastic realization Deterministic realization
Actual and predicted proportions of 1992 vegetation
Matching the actual map on a cell by cell basis
Scenarios for 2020 Grazing intensities do not change Grazing is excluded
Mediterranean type ecosystems
Guess if this photo was taken in Israel or in California
Oak woodland, chaparral, and grasses, in Carmel Valley, California
Precipitation patterns in California and Israel
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 Best match Worst match
Hastings Nature Reserve, Carmel Valley, California
A small part of 1939 photo Grassland Chaparral Trees
Same area in 1956
Same area in 1971
Same area in 1995
Vegetation maps of Hastings, California
Vegetation maps of Mt. Meron, Israel Herbaceous Vegetation Shrubs Trees
Change in tree cover in Meron and Hastings
Weight of predictors in affecting vegetation change
Average annual change Mediterranean vegetation change in long-term, landscape-scale studies
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 history
A transplant experiment is currently conducted, where oaks from both countries are grown together in both sites, in a controlled environment
More information on the various topics discussed here can be found in: 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.