干旱严重指数(DSI)在内蒙古地区的适用性分析

Applicability Analysis of Drought Severity Index(DSI)in Inner Mongolia

利用MODIS遥感产品计算内蒙古地区2000-2019年植被生长季的干旱严重指数(DSI),并结合气象干旱综合指数(MCI)、植被状态指数(VCI)等干旱指数和典型干旱过程,对DSI在内蒙古地区的适用性进行分析。研究表明,DSI与MCI、VCI的平均相关系数为0.509和0.839,分别通过0.05和0.01的显著性检验,具有较好的一致性。与MCI相比,DSI具有更高的空间分辨率,能反映不同植被类型抗旱能力的差异和区域植被改善后抗旱能力的增强。与VCI相比,DSI受高植被覆盖区归一化植被指数(NDVI)饱和现象的影响更小,并在干旱缓解期的灵敏性更高。DSI在内蒙古地区的适用性较好,可在干旱监测研究与业务中进行尝试和使用。

The DSI(Drought Severity Index)during vegetation growing season in Inner Mongolia from 2000 to 2019 is calculated using MODIS products,and the applicability of DSI in Inner Mongolia is analyzed based on typical drought events and drought indexes such as MCI(Meteorological drought Composite Index)and VCI(Vegetation Condition Index).The results show that the average correlation coefficients of DSI with MCI and VCI are 0.509 and 0.839,passing the significance test of 0.05 and 0.01,respectively,with high consistency.Compared with MCI,DSI has a higher spatial resolution and can reflect the difference in drought resistance of different vegetation types,as well as the enhancement of drought resistance ability after the improvement of regional vegetation.Compared with VCI,DSI is less affected by NDVI saturation in high vegetation coverage areas,and has higher sensitivity in drought relief periods.DSI is suitable for drought monitoring in Inner Mongolia,and can be used in drought monitoring researches and operations.