Using radar polarimetry to monitor changes in backscattering mechanisms in landslide zones for the case study of the Bureya river bank collapse

The possibilities of radar polarimetry methods for identification of landslide zones are analyzed here. The fact of transformation of the dominant scattering type by the reflecting surface was used as a key feature of the landslide zone. ALOS-2 PALSAR-2 polarimetric data were processed using the Freeman–Durden and Cloude–Pottier decompositions for the four test sites selected in the area of a landslide caused by the Bureya river bank collapse. The decomposition results are consistent with each other in general, however, some areas show significant differences due to the specifics of the basic model provisions. It is shown that before the landslide event on the landslide area there were three main mechanisms of radar signal scattering: surface, volume, and double scattering. After the collapse, this area is characterized by a single scattering from the surface with large-scale irregularities and without vegetation. So, the landslide area can be confidently recognized. The considerable potential of using the radar polarimetry method for remote diagnostics of the effects of landslide phenomena has been demonstrated.