Microwave Remote Sensing of Soil Moisture
نویسنده
چکیده
Because of the large contrast between the dielectric constant of liquid water and that of dry soil at microwave wavelength, there is a strong dependence of the thermal emission and radar backscatter from the soil on its moisture content. This dependence provides a means for the remote sensing of the moisture content in a surface layer approximately 5 cm thick. The feasibility of these techniques has been demonstrated from field, aircraft and spacecraft platforms. The soil texture, surface roughness, and vegetative cover affect the sensitivity of the microwave response to moisture variations with vegetation being the most important. It serves as an attenuating layer which can totally obscure the surface. Research has indicated that it is possible to obtain 5 or more levels of moisture discrimination and that a mature corn crop is the limiting vegetation situation. 129 https://ntrs.nasa.gov/search.jsp?R=19850014924 2018-03-26T23:44:21+00:00Z
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