Extreme Precipitation Changes and Its Effects on Fractional Vegetation Cover in the Loess Plateau
Under the background of global warming,extreme precipitation events occurred frequently in the Loess Plateau,which significantly affected the social economy and vegetation ecosystem.Studying the characteristics of extreme precipitation in the Loess Plateau and their influence on fractional vegetation cover(FVC)could provide scientific support for ecological environment protection and regional sustainable development.Based on daily precipitation data from 64 meteorological stations and MODIS NDVI data in the Loess Plateau from 2000 to 2020,trend analysis and correlation analysis were used to analyze the spatiotemporal variation characteristics of extreme precipitation and FVC in the Loess Plateau,as well as the influence of extreme precipitation on FVC was discussed.The results show that the total precipitation PRCPTOT,moderate rain day R10mm,heavy rain day R20mm,heavy precipitation day R25mm),and precipitation intensity SDII in the Loess Plateau increases significantly from 2000 to 2020(P＜0.05).The heavy rain increases mainly in the western and northern of the study area,but the southern area experiences drought.From 2000 to 2020,FVC generally shows a significant increasing trend(P＜0.05),which mainly locates in the central and eastern of the study area,accounting for 32.00％ of the total study area.Only 4.91％ of the total area shows significantly decreasing trend,which mainly distributes in the southern of the study area.From 2000 to 2020,there is positive correlation between moderate rain day R10mm,heavy rain day R20mm,heavy precipitation day R25mm,precipitation intensity SDII and FVC in the Loess Plateau,which accounts for 22.33％,48.19％,14.36％,and 24.37％ of the study area respectively,and mainly distributes in the central area.During the past 20 years,extreme precipitation and FVC increases simultaneously in the Loess Plateau,extreme precipitation shows a positive effect on vegetation ecological improvement.However,the time scale is also important for extreme precipitation research,that is,the effect of extreme precipitation on FVC may be weakened on short time scales.
Loess Plateauextreme precipitationfractional vegetation cover(FVC)climate changespatial and temporal distribution
万方数据
维普
