人类活动与气候变化对东江流域径流变化贡献率定量分析

摘要

Precipitation,daily temperature and evaporation data from 28 meteorological stations and 4 e-vaporation stations,and daily streamflow data from 4 hydrological stations during 1959 -2000 are ana-lyzed by using the elastic coefficient method and the W-ANN model.Besides,construction of water reser-voirs and land use changes are also considered in the analysis to investigate fractional contributions of cli-mate changes and human activities as driving factors to streamflow variations.The results indicate that:① the change point of the streamflow of the East River Basin occurred in 1972,the streamflow was larger after 1972 than before 1972;② The increased precipitation and decreased evaporation resulted in the in-crease of streamflow.The fractional contribution of climate change to the increase of the streamflow is 0.27 ~0.77;③ Human activities led to the increase of the streamflow via changes of land use.Mean-while,the construction of water reservoirs or hydraulic facilities tends to modify the annual distribution of the streamflow significantly.The fractional contribution of human activities to the increase of the stream-flow is 0.23 ~0.73 and the fractional contribution decreases from the upper to the lower East River ba-sin.This research has theoretical and practical contribution to human knowledge of the driving factors be-hind streamflow variations and also to the scientific water resources management of the East River basin.%通过弹性系数法及小波－神经网络模型对1959－2000年东江流域4个径流测站、28个降水测站、4个气温蒸发测站的径流、降水、气温、蒸发数据做系统分析与模拟，定量研究了气候变化及人类活动对东江流域径流量变化的贡献率。研究表明：①1972年是东江径流变化的变异点，1972年后东江径流较1972年前增大；②东江流域降水增加，蒸发减少，是导致东江流域径流量增加的重要原因，气候变化对东江径流增加的贡献率约为0.27－0.77；③人类活动主要通过土地利用方式的改变而改变产汇流过程，导致径流量变化，大型水库的建设是东江流域径流年内分配显著改变的重要驱动因素，人类活动对东江流域径流量变化的贡献率约为0.23～0.73，其影响从上游到下游呈减弱趋势。研究对于气候变化与人类活动影响下，东江流域水资源管理具有重要理论及现实意义。