气候变化和人类活动对洮河输沙量变化的影响分析

根据洮河代表水文站近60年的输沙量资料,分析了洮河输沙量变化规律以及气候变化和人类活动对洮河输沙量变化的影响。结果表明:(1)洮河多年平均输沙量为2 295万t,输沙量从1990年开始呈明显递减并且有继续减少的趋势;(2)洮河各代表站输沙量均发生显著突变,突变年份发生在20世纪80年代末和90年代中上期,输沙量突变后比突变前有明显减少;(3)气候变化和人类活动共同影响下洮河输沙量呈减少趋势。总体上,气候变化对输沙量变化的影响要远小于人类活动的影响,20世纪90年代以前气候变化对输沙量的变化影响起主导作用,90年代以后人类活动的影响起主导作用。

Analysis on impacts from climate change and human activities on sediment discharge of Taohe River

Based on the sediment discharge data of recent 60 years from the representative hydrological stations along Taohe River，both the changing law of the sediment discharge from Taohe River and the impacts from the climate change and the human activities on the sediment change are analyzed herein. The result shows that：（1）the yearly mean sediement discharge of Taohe River is 22.95 million t，while the sediement discharge starts an obvious degression along with a trend of continuous decrease from 1990；（2）significnt abrupt changes of sediment discharges occur at all the representative hydrological stations along Taohe River，while the years of the abrupt change occurred at the end of the end of the 80s and the early-medium term of 90s in the last century，for which the sediement discharge after the abrupt change is obviously decreased than that befroe the abrupt change；（3）the sediement discharge from Taohe River shows a trend of decrease under the common impact from both the climate change and the human activities. Generally，the impact from the climate change on the sediment discharge is much less than that from the human activities； i.e. the dominant role was played by the impact from the climate change on the sediment discharge before the 90s of the last century and after that is played by the human activities.