Complex Hydrological Regimes, and Processes, In the Negev Arid Area, Israel

Abstract

Spatial relationships, or connectivity, represent a basic concern in our understanding of geomorphic processes, and their effects on the degree of connectivity along hillslopes, at the interface hillslopes-channels, and along streams, will affect the spatial redistribution of water resources, sediment movement, sediment deposition and consequently the operation of biological fluxes. High values of connectivity are indicative of an efficient system; while a low connectivity would encourage infiltration losses, sediment deposition, and spatial redistribution of water resources. Many factors may affect the degree of connectivity, and the importance of a given factor may vary in a wide range of local conditions. Climatologist use aridity indices to express the relationships between climatic and environmental variables. This approach leads to the idea that average annual rainfall, up to 300 mm, controls water availability for plants, soil properties, runoff generation and soil erosion [1, 2, 3, 4]. This approach may be valid for soil covered areas, and annual crops, very sensitive to rainfall. Its validity is questionable in drier areas where most of the surface is rocky, and the limited soil patches are saline.