基于植被供水指数的锡林浩特市干旱监测分析

Drought Monitoring Analysis in Xilinhot City Based on Vegetation Supply Water Index

以锡林浩特市为研究区域,利用MODIS遥感影像数据提取的归一化植被指数和地表温度,计算植被供水指数对2009年、2013年和2017年的旱情分布情况进行监测。结果表明:锡林浩特市植被生长季普遍发生农业干旱,程度有所不同;在空间上干旱主要分布在锡林浩特市的北部和中西部地区,东部干旱程度较轻且零星分布在各个旗县;在时间上从2009-2017年研究区干旱程度逐年减轻,重旱发生区域逐年减少,干旱治理成效较为明显;植被供水指数法与单一植被指数(归一化植被指数)的监测结果大致一致,且数据易于获取,可操作性强,有助于提高监测精度和效率,可用于该研究区以及与其地形和覆被等情况一致区域的农业干旱监测。

Taking Xilinhot city as the study area,the normalized difference vegetation index(NDVI)and land surface temperature(LST)extracted from MODIS remote sensing image data were used to calculate the vegetation supply water index(VSWI)and monitor the drought distribution in 2009,2013 and 2017.The results showed that agricultural drought generally occurred in the vegetation growing season in Xilinhot city with different degrees.Spatially,drought was mainly distributed in the north and central and western regions of Xilinhot city.In the east,the drought degree was light and scattered in each banner.In terms of time,the drought degree in the study area decreased year by year from 2009 to 2017,and the severe drought occurred in the study area decreased year by year,drought control effect was relatively obvious;the monitoring results of vegetation supply water index method and normalized difference vegetation index(NDVI)were roughly consistent,and the data were easy to obtain and had strong operability.It was helpful to improve the monitoring accuracy and efficiency,and can be used for agricultural drought monitoring in the study area and the area consistent with its topography and plant cover.