干旱区地理2017，Vol.40Issue(2)：304-312,9.
半干旱草原型流域不同时间尺度降水特征分析
Precipitation characteristics at different time scales for a semi-arid steppe watershed
摘要
Abstract
Analysis of the precipitation characteristics has been paid wide attention in recent years because it is an important hydrologic factor that is intimately connected with the distribution of water resources and the human life.However,previous researches about the precipitation characteristics were most carried out in arid and semi-arid regions of northwest China,it cannot reflect the steppe watershed.Therefore,an analysis of the precipitation characteristics for a steppe watershed is necessary.By using the daily precipitation data obtained from Xilinhot meteorological station from 1960 to 2015,M-K,R/S and Morlet's wavelet methods were used to analyze the precipitation trend and abrupt change characteristic,the future trend,and the precipitation cycles at different time scales in a semi-arid steppe watershed—the Xilin River Basin,Inner Mongolia,China.The results show that the annual precipitation presented a nonsignificant decreasing trend and four abrupt changes took place in 1974,1980,1989 and 1998 during recent 56 a.There were a major cycle of 28 a,and two minor cycles of 4 a and 6a which occurred in the period from middle 1970s to the late 1990s and after the late 1990s,respectively.At the seasonal scale,the characteristic of summer precipitation was basically consistent with that of the annual precipitation,the rainfall of autumn had a large fluctuation,and the precipitation of the other two seasons both increased,especially in winter,the precipitation presented a significantly increasing trend.The precipitation in August of the flood season presented a significant decreasing trend and changed in 1998,and the first major cycle was 12 a.The precipitation in November and December of the non-flood season demonstrated a significantly increasing trend,therein,precipitation in December in 2000 showed a significant abrupt change.The first major precipitation cycles during the two months were 30 a and 9 a,respectively.The Hurst indices of the precipitation series at different time scales were all greater than 0.5,indicating that the precipitation had a persistent trend,the change of future precipitation will be consistent with that of the past.This conclusion can provide a reference for the management of water resources and ecological protection in Xilin River Basin in the future.However,the precipitation data selected in this study has some limitations.Besides,in recent years,with the process of urbanization,the transformation of basin underlying surface caused by human activity is also increasing,which also has an effect on the precipitation in this region.Therefore,the influence of human activities on the precipitation will be taken into consideration in further research.关键词
半干旱草原型流域/时间尺度/降水趋势/突变及周期Key words
semi-arid steppe watershed/time scales/precipitation trend/abrupt change and cycles分类
天文与地球科学引用本文复制引用
李玮,刘廷玺,格日乐吐,段利民,高瑞忠,Buren SCHARAW..半干旱草原型流域不同时间尺度降水特征分析[J].干旱区地理,2017,40(2):304-312,9.基金项目
国家国际科技合作专项(2015DFA00530) （2015DFA00530）
教育部创新团队发展计划(IRT13069)联合资助 （IRT13069）
