The phenology of an agricultural region as expressed by polarimetric decomposition and vegetation indices

The monitoring of vegetation biophysical characteristics in agricultural regions has traditionally been achieved using visible and infrared data. However, limitations to long-term monitoring are associated with cloud-cover. In this paper we consider the use of fully polarimetric SAR data and H-A-α decomposition to characterize the link between the different phenological stages of crops and the change in their scattering behaviour over time. The results demonstrated that the analysis of scattering mechanisms observed on fully polarimetric data can provide information regarding the peak of the growing season, the time-frame associated with harvesting and the monitoring of regrowth of crops. Additionally, changes in the roughness conditions of soils associated with harvesting, tilling and planting was observed. This suggests that polarimetric data is complementary to traditional vegetation indices derived from visible and near infrared sensors.