Response of microwave scattering from crop (wheat) and crop covered soil moisture for remote sensing

Abstract

The present study investigates the potential use of active microwave observations at 9.5 GHz frequency of X-band to monitor soil moisture and vegetation leaf area index (LAI) over a wheat cover for remote sensing. Using an X-band (9.5 GHz) scatterometer, measurements have been made out for different growth stage of crop (wheat). The leaf area index (LAI) is an important parameter for understanding the crop characteristics. Here an attempt has been made to highlight the effect of crop (wheat) LAI and crop covered soil moisture (<i>m</i>_g) on microwave scattering. Using simple scattering model, an empirical relation has been developed for observing the LAI and <i>m</i>_g<i> </i>effect on scattering coefficient. The angular and

polarization dependence of scattering coefficient on crop LAI and crop covered soil moisture has been investigated, which indicates that, when incidence angle is less than 30°, the crop (wheat) covered soil moisture is well observed, whereas when the incidence angle is greater than 30°, crop effect is more dominant at 9.5 GHz<i>. </i>The VV-polarization is more sensitive to sense the crop effect than HH-polarization. This type of study is helpful to make the algorithm for air- or space-borne data to access the crop parameters and crop covered soil moisture. All the data can also be used as reference data for space-borne sensors.