In-Situ and Remote Soil Moisture Sensing Technologies for Vadose Zone Hydrology

摘要

Serious threats to water resources are increasing as the world population is growing and more land is needed to produce food, fiber, and biofuels. Climate change is adding additional uncertainty. It is expected that water scarcity will continue to intensify in arid and semiarid areas and that humid areas will increasingly experience water shortages. The vadose zone plays a key role in many important hydrological processes, such as infiltration, runoff, soil water storage, root water uptake, and groundwater recharge. In managing limited water resources, water managers need a suite of decision support systems and management tools. Vadose zone soil water sensing, through in situ or remote techniques, has been proven extremely useful in this regard. A variety of in situ and remote soil water sensing techniques have been developed, tested, and used with different levels of success over the past decades. Observations using these two major types of soil water sensing methods are for different volumes, andwith different spatial and temporal resolutions.