Arid Dune Ecosystems (eBook) von Siegmar-W. Breckle

The North-Western Negev.- Geological Background of the Nizzana Area.- Geo-Ecology of the North-Western Negev Sand Field.- Formation and Geomorphology of the North-Western Negev Sand Dunes.- The Regional Climatic Setting.- Soil Characteristicsand Pattern of the Nizzana Research Site.- Land Use and its Effect on the Mobilization and Stabilization of the North-Western Negev Sand Dunes.- Ecosystem Patterns.- The Flora of the Nizzana Research Site.- The Vegetation of the Nizzana Research Site.- A Glance on the Fauna of Nizzana.- Biological Crusts.- Land Cover in the Nizzana Sandy Arid Ecosystem. Mapping Surface Properties with Multi-Spectral Remote Sensing Data.- Ecosystem Processes.- Topoclimate and Microclimate.- Evapotranspiration, Transpiration and Dewfall.- Morphological Changes at Active Dune Crests.- Aeolian Sand Transport and Vegetation Cover.- Soil Processes and Salt Dynamics in Dune Soils.- Runoff and Erosion Processes Within a Dune System.- Effects of Surface Runoff and Subsurface Flow on the Spatial Variability of Water Resources in Longitudinal Dunes.- Atmospheric Input of Nutrient Elements and Dust into the Sand Dune Field of the North-Western Negev.- Succession Stages in the Recovery Processes of the Topsoil Crust in a Disturbed Sandy Arid Area.- Dew Formation and Activity of Biological Soil Crusts.- Nitrogen Input Pathways into Sand Dunes: Biological Fixation and Atmospheric Nitrogen Deposition.- Vascular Plant Response to Microbiotic Soil Surface Crusts.- Ion Relations of Plants and Soil Patterns.- Temporal and Spatial Variability of Plant Water Status and Leaf Gas Exchange.- Standing Biomass and its Modelling.- Effects of Shrubs on Annual Plant Populations.- Demography of Annual Plants: The Role of Habitat Heterogeneity and Competition.- Research Perspectives / Synthesis and General Conclusions.- Sensitivity of a Sandy Area to Climate Change Along a Rainfall Gradient at a Desert Fringe.- General Conclusions Sand Dune Deserts, Desertification, Rehabilitation and Conservation.

Sand dune dynamics plays a key role in many arid deserts. This volume provides a synthesis of a specific sand dune ecosystem, the Nizzana site in the Negev Desert. Describing its climate and geophysical/geochemical properties of soils, geological history, flora and fauna, and past/present land-use patterns, it elucidates ecological and geomorphological processes and their interrelations, based on long-term monitoring, in situ experiments and satellite imagery. Particular attention is drawn to the impact of the topsoil biological crust in controlling water availability at local/regional scales. The interdisciplinary approach adopted in this case study offers a good example of a highly complex and dynamic system, which could easily be applied to other sandy ecosystems.

This is a valuable source of information for soil ecologists and microbiologists, conservation biologists, desert ecologists and geographers, geomorphologists, soil scientists and climatologists, lecturers, policy makers and others interested in deserts and desertification.