气候变化对冰川融水型河流水情的影响──以玛纳斯河为例

STUDY ON INFLUENCES OF CLIMATIC CHANGES ON MELTWATER HYDROLOGY──Taking Manas River Basin as an Example

我国西北地区的河流主要靠冰雪融水补给。８０年代新疆北部气候变化突出，分析玛纳斯河流域实测水文气象资料表明，８０年代年平均气温升高０．６℃，流域年降水量平均比５０—７０年代增加１６％，但河流水量趋于减少，年最大洪水减小１２．４％，河流径流的年内分布的不均匀性明显改变；春季水量增加，消融期提前，５月流量增大１９．５％，夏季略有减小。降水增多对河流径流影响不大，大河水文对气候变化的反应强烈，气候变化使河流水情向着不利于绿州经济与环境的方向发展。

Many rivers in the Northwest China are supplied by meltwater. Climatie change isvery outstanding in the northetn side of Tiaithan Mts.,Hydrological and metebrologicaldata of Manas River basin show that thelr runoffs in 1980s were tending to decrease al-though the annual air temperature has risen up, 0.6℃and the annual precipitation. has in-creased,12%and 29% more than 1950s and 1970s respectively. The greatest flood of Manasriver decreased 12.4%and annual distribution has changed moro greatly;water increasedmainly in Spring and Winter.and the ablation period are headed earlier;the discharge inMay inereased about 19.5% more than 1950s-1970s while it reduced a little in summer,theinerease of 10%-20% of the prccipitation cant make up runoff,the hydrological respondof meltwater in iarger river to the climatic change is more considerabie,this variation of theriver regime is disadvantageous to develop local economy and to protect environment ofoases in the arid desert zone.