Potential of ASAR/ENVISAT for the characterization of soil surface parameters over bare agricultural fields

REMOTE SENSING OF ENVIRONMENT

卷:96

Article

Holah, N ; Baghdadi, N ; Zribi, M ; Bruand, A ; King, C

关键词: soil moisture;    soil surface roughness;    ASAR images;   

DOI  :  10.1016/j.rse.2005.01.008

来源: Elsevier

【 摘 要 】

The objective of this investigation is to analyze the sensitivity of ASAR (Advanced Synthetic Aperture Radar) data to soil surface parameters (surface roughness and soil moisture) over bare fields, at various polarizations (HII, HV, and VV) and incidence angles (20'-43''). The relationships between backscattering coefficients and soil parameters were examined by means of 16 ASAR images and several field campaigns. We have found that HH and HV polarizations are more sensitive than VV polarization to Surface roughness. The results also show that the radar signal is more sensitive to surface roughness at high incidence angle (43). However, the dynamics of the radar signal as a function of soil roughness are weak for root mean square (rms) surface heights between 0.5 cm and 3.50 cm (only 3 dB for lift polarization and 43 incidence angle). The estimation of soil moisture is optimal at low and medium incidence angles (20 37). The backscattering coefficient is more sensitive to volumetric soil moisture in Fill polarization than in HV polarization, In fact. the results show that the depolarization ratio sigma(0)(HH)/sigma(0)(HV) is weakly dependent on the roughness condition, whatever the radar incidence. On the other hand, we observe a linear relationship between the ratio sigma(0)(HH)/sigma(0)(HV) and the soil moisture. The backscattering coefficient ratio between a low and it high incidence angle decreases with the rms surface height, and minimizes the effect of the soil moisture. (c) 2005 Elsevier Inc. All rights reserved.

【 授权许可】

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