Assessing water demand with remote sensing for two coriander varieties

Abstract

The use of remote sensing to determine water needs has been successfully applied by several authors to different crops, maintaining, as an important basis, the relationship between the normalized difference vegetation index (NDVI) and bio-physical variables, such as the fraction of coverage (f c ) and the basal crop coefficient (K cb ). Therefore, this study quantified the water needs of two varieties of coriander (UNAPAL Laurena CL and UNAPAL Precoso CP) based on the response of f c and K cb , using remote sensors and a water balance according to the FAO-56 methodology. A Campbell Scientific meteorological station, a commercial digital camera and a portable spectro radiometer were used to obtain information on the environmental conditions and the crop. By means of remote sensing associated with a water balance, it was found that the water demand was 156 mm for CL and 151 mm for CP until the foliage harvest (41 d after sowing); additionally, the initial K cb was 0.14, the mean K cb was 1.16 (approximately) and the final K cb was 0.71 (approximately).