基于MODIS数据的河套灌区遥感干旱监测

基于MODIS数据,以河套灌区为研究对象,计算灌区2000—2018年作物主要生育期内(5—8月)4种遥感干旱指数、温度植被干旱指数(TVDI)、植被供水指数(VSWI)、植被状态指数(VCI)、温度状态指数(TCI),并分析了4种干旱指数与0～20cm土壤相对含水量、降水量、灌区引水量相关性以及4种干旱指数之间的相互关系。结果表明:经过相关分析,TVDI与土壤相对含水量的相关性优于其他3种遥感干旱指数;在灌溉水量较多的灌区,遥感干旱指数与降雨量相关性较小而与灌区引水量呈现一定的相关关系。本研究发现TVDI在河套灌区有着良好的适用性。此外,在干旱监测中综合利用多种干旱指数进行分析对提高监测精度,科学合理地预报旱情具有重要意义。

Remote sensing drought monitoring of Hetao irrigation area based on MODIS data

Based on MODIS data, four remote sensing drought indexes(temperature vegetation drought index(TVDI), vegetation water supply index(VWSI), vegetation condition index(VCI)and temperature condition index(TCI))during the main growth period of crops(May-August)in the Hetao irrigation area from 2000 to 2018 are investigated. The relationship between the four drought indexes and their correlations with the relative water content of 0-20 cm soil, precipitation and irrigation water diversion are analyzed. The results show that: The correlation between TVDI and soil relative water content is better than the other three remote sensing drought indexes through correlation analysis; In the irrigation area with more irrigation water, the correlation between remote sensing drought index and rainfall is weak. However, there is a certain correlation between TVDI and irrigation water volume. Through the analysis, it is found that TVDI has a good applicability in Hetao irrigation area. In addition, the comprehensive use of various drought indexes in drought monitoring is of great significance to improve monitoring accuracy and predict drought scientifically and reasonably.