Fig. 7. Israel International Long-Term Ecological Research site. The Israel research project analyzes how human decisions and activities affect the distribution of resources (soil, water, and nutrients) in a rangeland ecosystem. The model depicts the social and ecological factors that affect grazing conditions in semi-arid shrub lands in South Israel. Key variables include nitrogen, sheep, and grazing management by Bedouins. Grazing affects productivity and the diversity of shrub patches and intershrub patches. The risks of desertification are increasing as the Bedouin semi-nomadic culture becomes increasingly sedentary and livestock rearing becomes less popular.