Designation: Ecosystem research and management under livestock grazing and climate change. Climate: Mean annual precipitation 150-200mm (Fig. 2) between November and April; mean maximum summer temperature 34° C, mean minimum winter temperature 6° C. (Data available for 15-min interval meteorological measurements and daily summaries for rainfall, air and soil humidity and temperature, wind velocity and direction, from 1997 to the present.) Principal biomes: Semiarid shrub land (shrub-grass steppe), rocky and loess watersheds, ephemeral streams. Vegetation is dominated by patch-forming dwarf shrubs (Noaea mucronata, Atractylis serratuloides and Thymelea hirsuta) with species-rich annual winter vegetation in the inter shrub (dominated by Stipa capensis and other grasses) and shrub patch understory (dominated by Anagallis arvensis and other forbs). Management: Livestock grazing excluded in central watershed (20 ha) since 1987; restricted/controlled grazing by Bedouin sheep herds in surroundings; in the outer parts of the area native and exotic trees were planted in 1985-87 in contour dykes (‘shikhim’). Research: 1. Long-term experiments (up to 20 years) for monitoring changes in abundance, diversity, species composition and distribution, and development of biological soil crusts (BSC), perennial plants (dwarf shrubs) and winter annuals in relation to rainfall, soil disturbance, patch distribution, and livestock grazing. 2. Short-term experiments and surveys (1 to 5 years) for testing hypotheses about the detailed processes, mechanisms and interactions involved in the development, dynamics and stability of shrub- and BSC-dominated patches, their landscape mosaic patterns and their feed-back relationships with flows of materials through the landscape. 3. Network-related research including regional comparisons of herbaceous plant productivity in open rangeland along the Israeli North-South rainfall gradient, and global comparison of woody plant diversity effects on ecosystem functionality of most dryland regions of the world.
Purpose of Site:
Ecosystem research and management under livestock grazing and climate change; Small to large scale relationships between landscape, vegetation, hydrology, nutrient dynamics; Sustainable livestock grazing, land degradation, recovery, restoration; Temporal vegetation responses to inter-annual variation in rainfall; Patch and pattern formation by dwarf shrubs, annual herbs and biological soil crusts; Biological soil crust development, disturbance, function and species composition; Regional and global comparisons of dryland ecosystems.