Estimation of crop evapotranspiration of irrigation command area using remote sensing and GIS

This paper describes the use of satellite-based remote sensing (RS) data and geographic information system (GIS) tools for estimating seasonal crop evapotranspiration in Mahi Right Bank Canal (MRBC) command area of Gujarat, India. Crop coefficients (Kc) for various major crops grown in MRBC were estimated, empirically, from the RS derived soil adjusted vegetation index (SAVI) values. A reference crop evapotranspiration (ET0) map was generated from point meteorological observations. The Kc and ET0 maps were combined to generate seasonal crop evapotranspiration (ETcrop) map which highlighted spatial variation in ETcrop ranging from more than 600 mm for healthy tobacco crops to less than 150 mm for very poor wheat crops.