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.