摘要
利用黄河源区的4个水文站及13个气象站的日系列资料,基于改进的加里宁基流分割法,分析了1956—2000年以来黄河源区基流和以水文站为节点控制的各个子流域的基流变化及其影响因素.结果表明:黄河源区基流比例较大,多年平均基流指数为0.652;黄河沿以上流域基流指数为0.556,黄河沿-吉迈区间基流指数为0.588,吉迈-玛曲区间基流指数为0.649,玛曲-唐乃亥区间基流指数高达0.704.从绝对量来看,黄河源区多年平均基流量为132.46×108m3;子流域中,玛多以上流域基流量最小,为3.92×108m3,吉迈-玛曲区间基流量最大,为68.82×108m3.对于整个研究区,年降水量决定年基流量,气温影响基流,气温升高,基流减少.不同子流域的基流对气候变化响应不同,玛曲以上各个子流域基流随气温升高而减少,而在玛曲-唐乃亥区间年气温对年基流量无明显影响.黄河源区年代尺度基流指数和降水量成反比关系.
The purpose of this study is to identify and assess the change of baseflow and climatic impacting factors in the source regions of the Yellow River, based on the analyses of long hydrological time series （1956--2000） from four subbasins of the source regions of the Yellow River and the whole source regions of the Yellow River. Kalinin baseflow separation technique has been improved based on the characteristics of climate and streamflow of the study regions, then applied to estimate baseflow. Statistical method is adopted in order to investigate the effect of climate factors on baseflow. Annual mean baseflow in the source regions of the Yellow River is 13. 246 billion m3, accounting for more than 60% of the total runoff of the area interested. Annual baseflow is in direct proportion to annual precipitation. The sharp rise in tem perature in the 1990s decreased baseflow significantly. The impacts of climate factors on baseflow are different in different subcatchment. In subba sin above Huangheyan Hydrologic Station, which is relative cold and arid with annul mean temperature of --3.84 ℃ and the water area accounted for 7.95% of the subbasin, both temperature and precipitation nearly had no direct impacts on baseflow on annual time scale. The increasing temperature thaws frozen soil more rapid, thus lowers the groundwater table and lake water level, hence decreases water supply of baseflow from groundwater and lake water. In subbasin between Huangheyan and Jimai Hydrologic Station baseflow is influenced both by precipitation and temperature but the response rate of baseflow to precipitation is more rapid than temperature. In subbasin between Jimai and Maqu Hydrologic Stations precipitation and temperature area two key factors impacting baseflow, but the effect of precipitation is more pronounced than temperature, while in suhbasin between Maqu and Tangnag Hydrologic Station precipitation is the only climate factor affecting baseflow in short term. The factors inducing serious decrease of haseflow in the 1990s are also investigated into.
出处
《冰川冻土》
CSCD
北大核心
2006年第2期141-148,共8页
Journal of Glaciology and Geocryology
基金
国家重点基础研究发展规划项目(G1999043601)资助
关键词
黄河源区
基流
降水
气温
source regions of Yellow River
baseflow
precipitation
temperature
