Capability of multi-temporal Radarsat-2 data in monitoring canola crop and its plant height

The potential capability of C-Band fully polarimetric synthetic aperture radar data for monitoring canola height was investigated in this study. Polarimetric parameters of canola fields were extracted with polarimetric decompositions method from multi-temporal Radarsat-2 images. Temporal behavior of polarimetric features with different varieties and sowing dates was presented from its sowing to its harvest. It was found that the evolution curve of Entropy and Alpha-angle parameters is highly consistent with the evolution trend of canola height over time. A second order polynomial model was applied to inverse the canola height over a farmland area of China, during the 2013 growing season. Even if the proposed method is simple, the result was encouraging with a high level of agreement (R²=0.96, RMSE=13.1cm, RE=14.3%). Therefore, it revealed a strong capability of polarimetric synthetic aperture radar data in characterizing canola plant height, especially in vegetative growth stage.