REMOTE-SENSING OF CROP PARAMETERS WITH A POLARIZED, FREQUENCY-DOUBLEDND-YAG LASER

Polarized laser remote-sensing measurements that correlate the yield, the normalized difference vegetation index, and the leaf area index wi th the depolarized backscattered radiation from corn plots grown with eight different nitrogen fertilization dosages are presented. A polari zed Nd:YAG laser emitting at 1064 and 532 nm is used. Depolarization i ncreased significantly with increasing fertilization at the infrared w avelength, and there was a decrease in the depolarization at the green wavelength. The depolarization spectral difference index, defined as the absolute difference in the depolarization at the two wavelengths, is introduced as a parameter that is an indicator of the condition of the internal leaf structure.