中文摘要：

面对珠江水量统一调度的新要求,采用Copula函数对珠江流域内3个控制性水文站的径流量进行研究,分析其丰枯遭遇概率。结果显示：1）三大水系两两间丰枯同步的概率大于丰枯异步的概率（汛期西江和东江除外）,其中北江与东江径流量一致性较好,丰枯同步的概率最大,其中全年丰枯同步的概率高达69.88%,汛期丰枯同步的概率为63.36%;西江与东江丰枯同步的概率最小,汛期只有47.88%;西北江丰枯同步的概率居中,全年、汛期和非汛期丰枯同步的概率分别为55.10%、56.02%和50.12%。2）三大水系三维联合分布研究表明,三大水系丰枯同步的概率在全年、汛期和非汛期均较大,依次为40.16%、38.11%和36.49%,其中同丰和同枯的概率远大于同平的概率。3）利用三大水文站的联合分布,可获得各水文站不同径流量遭遇的概率,以及特定概率下各水文站径流量的可能组合,可对珠江水量统一调度提供参考。

英文摘要：

The Pearl River Basin holds an important economic, political and social status in China. The runoff of the Xijiang river,Beijiang river and Dongjiang river affects the regional flood safety and the safety of drinking water directly. Considering the critical requirement of unified schedule of the Pearl River, this paper constructed 2-dimensional and 3-dimensional joint distributions of runoff of the three river systems based on copula functions, and analyzed their wetness-dryness encountering probability. The basic conclusions are obtained as follows：1） the synchronous wetness-dryness probabilities of any two rivers are higher than the asynchronous ones（except the Xijiang and the Dongjiang in flood seasons）. The synchronous wetness-dryness probabilities of the Xijiang and Beijiang, or the Xijiang and Dongjiang are relatively small, which offers the possibility of wetness-dryness compensation between the Xijiang and the other two rivers. 2） The 3-dimensional joint distribution indicates that the synchronous wetness-dryness probabilities of the three rivers on annual scale, in flood seasons and non-flood seasons are 40.16%, 38.11% and 36.49%, respectively, with the probability of synchronous wetness and dryness much larger than that of synchronous normal ones. 3） By the joint distributions constructed above, we can get the probabilities of any runoff combinations of the three rivers, as well as diverse runoff combinations under certain probabilities. And all of those will provide important reference for unified schedule of the Pearl River.