Monitoring model of corn lodging based on Sentinel-1 radar image

Based on the analysis of the polarization index of the Sentine-1 radar image before and after the lodging, the lodging classification model at the regional scale is established. The polarimetric index of Sentinel-1 radar image was extracted and analyzed according to the correlation analysis between the lodging index before and after the lodging. The degree of lodging was divided by the difference of plant height before and after lodging, and finally the lodging classification model was obtained. The results of correlation analysis showed that the optimal sensitivity index of maize plant height before and after lodging was VH and VV+VH, respectively. The final lodging classification model of the total sample point of lodging degree of classification accuracy was: mild lodging 97%, moderate lodging 100%, serious lodging 83%. The results show that Synthetic Aperture Radar (SAR) can effectively evaluate the degree of maize lodging at the regional scale.