以黑龙江军川农场为研究区域,应用Landsat TM卫星遥感数据计算和反演归一化植被指数和地表温度,采用条件植被温度指数(VTCI)的方法对该区域进行土壤表层水分监测。通过与同一时期的LST和NDVI模型的反演结果进行对比,结果表明:VTCI与该模型的纹理特征相似,干旱的分布规律几乎一致。应用土壤表层含水量数据对干旱监测结果进行验证,验证结果表明VTCI与土壤表层含水量有较好的线性相关性,进一步证实了VTCI是一种实时的干旱监测方法。
Landsat TM images are used to calculate and retrieve normalized difference vegetation index (NDVI) and land surface temperature (LST). Vegetation temperature condition index (VTCI) drought monitoring approach is applied to monitor droughts and to retrieve surface soil moisture in Junchuan farm of Helongjiang Province in Northeast China. Soil surface moisture retrieval methods based on NDVI - LST and VTCI models are developed and compared, and the results show that the spatial distributions of soil surface moisture are similar for the two models. The drought monitoring resuits are validated by using ground measured soil surface moisture. The results indicate that a good linear correlation between VTCI and soil moisture at surface layers (0- 10 cm and 0 - 20 cm) respectively, and further confirm that VTCI approach is a real time drought monitoring approach.