Defining the sensitivity of polarimetric parameters to crop residue patterns during-harvest

The sensitivity of polarimetric parameters to different residue patterns during harvest has been investigated in the paper. Several crop residue cover types called residue patterns during harvest have been selected. They include harvested wheat fields with burned and non-burned straws, the swathed oilseed rapes with different moisture, the rape swathes aligned in different directions, the non-lodging wheat and lodging wheat before harvest. A set of polarimetric parameters include backscattering coefficients, coherence coefficients, polarimetric phase differences, and variables derived from Cloude decomposition are made use of. Sensitivity analysis was conducted on one Radarsat-2 quad-pol image and one TerraSAR-X dual-pol image acquired over a farmland of China. The results indicate that polarimetric parameters have various responses to different residue patterns. The residue amounts, direction and crop harvest state are the main factors that result in the fluctuation of polarimetric scattering characteristics. In addition, it is revealed that multi-polarimetric image with short wavelength has the potential to guide the farming behaviors during harvest.