NATO Science Series, Applied Hydrogeophysics, pp.75-116
The vadose zone, i.e., the part of subsurface above thewater table, is home to a number of key processes that control the mass and energy exchanges between the subsurface and the atmosphere. Vadose zone hydrology provides boundary conditions for both atmospheric processes, including micro-meteorology and climatic changes, and subsurface water migration, with strong implications in water resources management. The rates, timing, and patterns of aquifer recharge are controlled by percolation through the vadose zone. Contaminants released near the ground surface can be altered, retarded or wholly removed by biological, chemical and physical processes in the vadose zone before reaching underlying aquifers. Unsaturated processes control also the availability of water for agriculture, and are the driving mechanisms in slope stability, floods and other major engineering geology problems. Fewhydrological problems of practical interest can neglect the importance of the complex, non linear dynamics of vadose zone processes. However, in practice, the impact of the vadose zone on hydrologic problems is often ignored or treated using highly simplified approximations, mainly because of limited available data in this region. A proper characterization of the vadose zone should also account for the natural variability of the soil properties at different scales.
Geosciences ; Hydrogeology ; Geophysics/Geodesy ; Soil Science & Conservation ; Environmental Physics ; Terrestrial Pollution ; Geography