Retrieval of soil moisture based on MODIS shortwave infrared spectral feature
基于MODIS短波红外光谱特征的土壤含水量反演

Soil moisture is one of the most important parameters characterizing surface dryness conditions and its retrieval by quantitative remote sensing methods has been a challenging scientific problem. In this paper, we analyze the sensitivity of shortwave infrared MODIS band 6 and band 7 to the changes of water to construct the MODIS shortwave infrared spectral feature space. According to the soil moisture variation in spectral feature space, we put forward a simple and practical MODIS shortwave infrared soil moisture index (SIMI) and validate it using ground-measured 0-10cm averaged soil moisture of Ningxia plain. The results show that the coefficient of determination (R2) of both them varies from 0.39 to 0.58, and SIMI has higher accuracy than temperature-vegetation index (TVX) for soil moisture retrieval to support the reliability of this index for regional soil moisture retrieval. However, SIMI does not eliminate the impact of mixed-pixel and still needs further improvement and perfection.