蒙古高原生态干旱监测及时空变化OA

The Mongolian Plateau is an ecologically vulnerable region that is susceptible to increasingly severe drought threats due to intensifying global warming.To quantify the impact of drought on ecosystems,the stan-dardized ecological water deficit index(SEWDI)was calculated based on meteorological and remote sensing da-ta.This study systematically evaluated the application of the SEWDI in monitoring ecological drought on the Mongolian Plateau.It revealed the spatiotemporal evolution patterns of ecological drought from 1982 to 2022 and extracted ecological drought characteristics using run theory.The results of the study indicate that:(1)SEW-DI demonstrates stronger correlations with vegetation indices across temporal and spatial dimensions than tradi-tional drought indices,including the standardized precipitation evapotranspiration index,the standardized precipi-tation index,and the self-calibrating Palmer drought severity index.These findings suggest that SEWDI exhibits superior capability in characterizing ecological drought.(2)Over the past 40 years,ecological drought has intensi-fied significantly at a rate of-0.0168·a-1.The drying trend has been primarily concentrated in the northern re-gions,and the conditions have been more severe in Mongolia than in China's Inner Mongolia Autonomous Re-gion.The severity of drought conditions exhibited seasonal patterns,with the most pronounced exacerbation oc-curring during the summer months,followed by a notable intensification in spring and autumn.Conversely,a mar-ginal alleviation was observed during the winter season.(3)The ecological drought severity in the Mongolian Pla-teau is higher in the northern regions and lower in the southern regions.Furthermore,the duration of drought is prolonged in the northern regions and is comparatively reduced in the southern regions.The frequency is lower in the north and higher in the south,whereas the intensity is lower in the northwest and higher in the southeast.SEWDI has been shown to enhance the sensitivity and accuracy of ecological drought monitoring by integrating vegetation water demand and consumption dynamics.This integration provides a scientific basis for region-spe-cific drought resistance and ecological management strategies.