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以渭河流域为研究对象,选取1961~2010年为研究期,基于21个气象站和5个水文站的月降雨、径流及蒸发等资料,综合考虑气象干旱指数(降水距平百分率、标准化降水指数和修正Palmer指数)和水文干旱指数(河道来水量距平百分率),构建了综合干旱指数CDI,采用模糊综合评价法计算得出分区长系列CDI指数,并与PDSI指数和河道来水量距平百分率指数的结果进行对比,验证综合指数的可靠性,基于综合干旱指数分析了渭河流域近50年的干旱时空变化.结果表明:渭河中游、泾河流域、渭河上游、渭河下游、北洛河流域干旱逐渐变轻;20世纪90年代干旱程度迅速加重,最严重的情况出现在1986、1995和1997年;流域各分区干旱主要集中在春、秋两季,4月和11月变干趋势显著.研究成果可为渭河流域极端干旱事件的预防提供一定的参考,也可以应用到其他流域的干旱评价之中.“,”Taking the Weihe River Basin as the research object and based on the monthly rainfall, runoff and evaporation data at 21 meteorological and 5 hydrological stations from 1961 to 2010,considered meteorological drought (precipitation anomaly percentage, standardized precipitation index and revise Palmer index) and hydrological drought index (river inflow anomaly percentage),a comprehensive drought index (CDI) is built to compute the monthly CDI with fuzzy comprehensive evaluation method; and then the reliability of CDI is verified. Based on comprehensive drought index, the trend of temporospatial variation in Weihe River Basin is analyzed. The results show that the districts of drought from heavy to light are the midstream of Weihe River, Jinghe River, the upstream of Weihe River, the downstream of Weihe River, Beiluo River. Timescale,1990s is rapidly increased and severe drought is 1986,1995 and 1997. The basin arid is mainly concentrated in the spring, autumn and April,November. The research results can provide a reference for the prevention of the extreme drought events in Weihe River.