基于微波遥感技术的干旱监测指数及其应用研究——以三江源区为例

以三江源区为研究区,基于AMSR-E的亮度温度数据获得了微波极化差异指数(MPDI)、比值干旱指数(DI)和多时相微波干旱指数(PI),并分别对这3种指数进行了干旱监测有效性检验。为了获得研究区全区监测效果更好的干旱指数,对MPDI、DI和PI指数进行融合,最终获得的综合微波干旱指数(SDI)与土壤湿度数据和降水数据都存在很好的相关性,对比单个指数时监测干旱的有效性也得到了提高。最后,应用SDI指数对三江源区21世纪以来的干旱情况进行了监测研究。结果表明:基于AMSR-E的综合微波干旱指数(SDI)能有效的对干旱进行监测,充分发挥了被动微波遥感数据的优势,具有一定的应用价值,为后续利用多源的多传感器的微波遥感数据监测干旱的相关研究奠定了基础。

Drought Index and Its Application Based on Microwave Remote Sensing Technology:A Case Study in the Three-River Headwaters Region

The study area is located in the three-river headwaters region in China.The MPDI, PI and DI were extracted from the AMSR-E data, and the data of soil moisture content and precipitation were used to analyze the validation of the three indices in drought monitoring.In order to obtain a better drought monitoring in the study area, in this study a new microwave drought index, the synthesis drought index (SDI), was proposed by integrating the MP-DI,PI and DI.There were the good correlations between the SDI and the data of soil moisture content and precipitation, and the effect of drought monitoring was improved by comparing the single indices.Furthermore, the conditions and spatiotemporal change of drought since the 21st century were analyzed using the SDI,and a high accuracy was achieved.The results revealed that the SDI was a very reliable index in monitoring drought, its application prospect for the study area was wide, and a foundation was laid for further studying the drought monitoring with multiple sensors.