Drought and flood characteristics in the farmingpastoral ecotone of northern China based on the Standardized Precipitation Index  

作　　者：CAO Huicong YAN Dandan JU Yuelin 

机构地区：[1]Journal Department,Nanjing Forestry University,Nanjing 210037,China [2]Faculty of Humanities&Social Sciences,Nanjing Forestry University,Nanjing 210037,China [3]College of Biology and the Environment,Nanjing Forestry University,Nanjing 210037,China

出　　处：《Journal of Arid Land》2021年第12期1244-1259,共16页干旱区科学（英文版）

基　　金：This study was financially supported by the National Natural Science Foundation of China(41871097).

摘　　要：The farming-pastoral ecotone of northern China(FPENC)provides an important ecological barrier which restrains the invasion of desert into Northwest China.Studying drought and flood characteristics in the FPENC can provide scientific support and practical basis for the protection of the FPENC.Based on monthly precipitation data from 115 meteorological stations,we determined the changes in climate and the temporal and spatial variations of drought and flood occurrence in the FPENC during 1960-2020 using the Standardized Precipitation Index(SPI),Morlet wavelet transform,and inverse distance weighted interpolation method.Annual precipitation in the FPENC showed a slightly increasing trend from 1960 to 2020,with an increasing rate of about 1.15 mm/a.The interannual SPI exhibited obvious fluctuations,showing an overall non-significant upward trend(increasing rate of 0.02/a).Therefore,the study area showed a wetting trend in recent years.Drought and flood disasters mainly occurred on an interannual change cycle of 2-6 and 9-17 a,respectively.In the future,a tendency towards drought can be expected in the FPENC.The temporal and spatial distribution of drought and flood differed in the northwestern,northern,and northeastern segments of the FPENC,and most of the drought and flood disasters occurred in local areas.Severe and extreme drought disasters were concentrated in the northwestern and northeastern segments,and severe and extreme flood disasters were mainly in the northeastern segment.Drought was most frequent in the northwestern segment,the central part of the northeastern segment,and the northern part of the northern segment.Flood was most frequent in the western part of the northwestern segment,the eastern part of the northeastern segment,and the eastern and western parts of the northern segment.The accurate evaluation of the degrees of drought and flood disasters in the FPENC will provide scientific basis for the regional climate study and critical information on which to base decisions regarding environmental pro

关 键 词：farming-pastoral ecotone of northern China(FPENC) Standardized Precipitation Index(SPI) DROUGHT FLOOD Morlet wavelet transform 

分 类 号：P426.616[天文地球—大气科学及气象学]