Study on the retrieval of soil moisture by active and passive microwave remote sensing

摘要

In this paper, a active and passive microwave sensing combing algorithm is proposed, which merges L-band radiometer data and L-band radar data to obtain high-resolution soil-moisture in the premise that the soil roughness effect is not considered. The algorithm uses single-frequency single-incident angle measurements, considering effect of vegetation index (VI), establishs the relationship between volumetric soil-moisture and copolarized radar backscatter at L-band. The experiment exploits fine-scale spatial(10m) remote sensing data set by ALOS-PALSAR and coarse-scale radiometer soil-moisture to produce a high-resolution optimal soil-moisture estimate at 30m in the Heihe River Basin A'Rou. Then the capability of the algorithm is demonstrated by using measured data at high-resolution. The results show an improvement in root-mean-square error of 0.055cm3/cm3 and R2 is 0.7855. It indicates that the algorithm can obtain high accuracy of soil moisture estimate, and it is suitable for plain with homogeneous surface roughness.