土壤水分遥感监测及关键技术

Key Technology of Soil Moisture Monitoring by Remote Sensing

用遥感技术进行土壤水分监测已有超过30 a的历史,国内外学者在此领域也进行了不少的探索和研究。通过分析各种遥感土壤水分监测方法的特点,将其归纳为光学遥感和微波遥感2大类,其中,光学遥感又分为土壤热惯量法、温度植被指数法和蒸散法。根据国内外的研究现状,对应用遥感方法估算区域土壤水分的关键技术进行了深入的分析,其主要包括数据源的选取、参数反演、模型选择和精度验证4个方面。结果表明,长期以来由于这些关键技术没有得到很好的解决,极大地制约了基于遥感方法估算区域土壤水分的发展。通过对关键技术的分析,将有助于高精度遥感土壤水分监测模型的建立。

It has a long history over 30 years since soil moisture has been monitored by remote sensing and many researchers in this area have been engaged over the world. In this paper, the main methods of soil moisture monitoring by remote sensing were divided into optical remote sensing and microwave remote sensing two categories, and the optical remote sensing could be further divided into soil thermal inertia, NDVI-Ts and evapotranspiration. In this paper, key technologies were analyzed, which played an important role in the accuracy of soil moisture estimation using remote sensing data. Investigation on the key technologies which impacts the regional soil moisture estimated by using remote sensing data would help the establishment of high accuracy soil moisture model. Based on analysis of the major methods in this area, this paper points out that these key technologies mainly include： the selection of the source data, the inversion accuracy of land surface parameters, the selection of the soil moisture models, and the validation method.