Understanding the enhanced backscatter of coastal forest plantation in L-band synthetic aperture radar images

Forests usually present medium radar backscatter in SAR images; however, they can have extremely high backscatter if ground-trunk dihedral reflection cannot be neglected. In this paper, we demonstrated the extremely enhanced backscatter in L-band ALOS PALSAR image of a coastal forest plantation in Zhangpu, China. With the revised water cloud model and field measurements, we explained the mechanisms for the enhance backscatter. It is due to the ground-trunk corner reflector because of the internal structure of the forest and strong penetration of the L-band microwaves, and the high wetness of the forest understory. The understanding presented in this paper is useful for choosing the models and information retrieval methods to monitor this kind of forest.