The Potential Use of Multi-Band SAR Data for Soil Moisture Retrieval over Bare Agricultural Areas: Hebei, China

Remote Sensing

Xiang Zhang²  Baozhang Chen²  Hongdong Fan⁴  Jilei Huang²  Hui Zhao¹  Nicolas Baghdadi³ 

[1] National Geomatics Center of China, BeiJing 100080, China;School of Environment Science and Spatial Informatics, China University of Mining and Technology, Xuzhou 221116, China;;School of Environment Science and Spatial Informatics, China University of Mining and Technology, Xuzhou 221116, ChinaJiangsu Key Laboratory of Resources and Environmental Information Engineering, China University of Mining and Technology, Xuzhou 221116, China;

关键词: soil moisture;    TerraSAR-X;    Radarsat-2;    SVR;    Dubois model;   

DOI  :  10.3390/rs8010007

来源: mdpi

【 摘 要 】

The potential use of TerraSAR-X and Radarsat-2 data for soil moisture retrieval over bare agricultural areas was investigated using both empirical and semi-empirical approaches. For the empirical approach, the Support Vector Regression (SVR) model was used with two cases: (1) using only one C-band or X-band image; and (2) using a pair of C-band and X-band images jointly. For the semi-empirical approach, the modified Dubois model based on C-band and X-band SAR data was developed to estimate soil moisture content. The experiments were implemented over two bare agricultural areas, and in-situ measurements were carried out to assess the methods. The results showed that the TerraSAR-X and Radarsat-2 are suitable remote sensing tools for the estimation of surface soil moisture, with an accuracy of about 3 vol % (root mean square error, RMSE) over bare agricultural areas. Compared with the results obtained by Radarsat-2 data, TerraSAR-X data gives a slight improvement in estimating soil moisture. The accuracy of the soil moisture estimation was improved further when the two bands SAR data were used (RMSE of about 2.2 vol %) instead of only one. Moreover, the modified Dubois model showed comparable accuracy to the empirical model independent of the surface roughness.

【 授权许可】

CC BY   
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