In recent years, many researchers have made progress in the use of GPR as an alternative for TDR, time domain reflectometers, for determining field-scale variations of soil water content. These early TDR sensors came about in the 1980s and utilized the influence of water on the velocity of electromagnetic waves to obtain accurate measurements of soil water content; however, assessment of an entire field remained a tedious task because of the need to install a large number of TDR sensors to adequately cover the field. To overcome these difficulties, scientists have used GPR methods to map a field's varied soil moisture, as in the case with the California vineyards.
GPR's high-resolution information can be used to improve vineyard development and management, such as to develop vineyards within uniform "blocks" of soil that have optimal properties, or to improve precision irrigation approaches, says Susan Hubbard, long-time GPR researcher.
"Soil water content information obtained from GPR data can be extremely useful for guiding many environmental, engineering, and agricultural applications, such as in wine making. This is one example of a successful GPR application, but many others can be imagined," she adds.
Hubbard recently joined a group of scientists to review the current state-of-the-art methods for determining soil wate
Contact: Sara Uttech
American Society of Agronomy