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 isngrowing and more land is needed to produce food, fiber, and biofuels. Climate change isnadding additional uncertainty. It is expected that water scarcity will continue to intensify innarid and semiarid areas and that humid areas will increasingly experience water shortages.nThe vadose zone plays a key role in many important hydrological processes, such as infiltration,nrunoff, soil water storage, root water uptake, and groundwater recharge. In managing limitednwater resources, water managers need a suite of decision support systems and managementntools. Vadose zone soil water sensing, through in situ or remote techniques, has been provennextremely useful in this regard. A variety of in situ and remote soil water sensing techniquesnhave been developed, tested, and used with different levels of success over the past decades.nObservations using these two major types of soil water sensing methods are for differentnvolumes, and with different spatial and temporal resolutions.