Submitted to: Encyclopedia of Soil Science
Publication Type: Book / Chapter
Publication Acceptance Date: June 8, 2001
Publication Date: N/A
Interpretive Summary: Methods for measuring soil water content were summarized and compared for specific types of hydrologic and agricultural applications. The key techniques used today are significantly different than those employed even ten years ago. New methods that utilize electrical properties of the soil, including remote sensing, were described. These results will be of value to oa wide range of users. Individual farmers could use certain sensors for irrigation management and yield estimation. Management agencies could benefit from a combination of ground-based networks and remote sensing techniques.
Technical Abstract: Soil water content is a basic hydrologic state variable. It is used in applications that range in scale from irrigation management to flood forecasting. Soil water content has also increased in importance in weather forecasting and climate modeling as these disciplines have begun to recognize its importance in large-scale water cycles. As important as soil water is in human activities and food supply, it has not been as widely observed and monitored as other variables such as precipitation and temperature. This is due to inadequate instrumentation as well as the numerous scales of variability that effect this state variable. Techniques for measuring soil water content are described and compared for different applications.