枯季利用西江上游龙滩水库调节控制梧州流量以满足珠江河口压咸补淡的要求,是近年来保障河口地区供水安全的重要工程措施.文中将龙滩水库泄流过程与区间流域的自然径流过程作为整体统一考虑,利用数字流域模型建立龙滩-梧州区间无控开放性流域的降雨径流模拟分析系统;通过数值试验,分析了区间流域径流过程影响下梧州流量对龙滩泄流的响应关系.结果表明,龙滩泄流量是枯季梧州流量的主要组成部分,梧州流量与龙滩泄流量具有很好的线性关系,在枯水年和偏枯水年,龙滩最小压咸泄流量分别需要600m³/s和800m³/s;梧州流量对龙滩泄流的响应过程与龙滩泄流量及其变化有关,泄流量越大,变化越迅速,梧州流量的响应时间越短.

In recent years,the upstream Longtan Reservoir in Xijiang watershed is used to regulate the downstream Wuzhou flow in dry season for the purpose of saltwater suppression.This method has proved to be an important engineering measure to ensure the fresh water supply in the Pearl River Estuary area in dry season.In this paper,the reservoir discharge and the interval watershed runoff process between Longtan and Wuzhou are considered together as a whole and the rainfall-runoff of the non-controlled interval basin is modeled by using the digital watershed mo-del.Then,numerical experiments are carried out to analyze the response of Wuzhou flow rate to Longtan discharge affected by the watershed runoff process.The results show that（1） as a major component of Wuzhou flow in dry season,Longtan reservior discharge is linear to Wuzhou flow rate;（2） the lowest discharges for saltwater suppre-ssion are respectively 600 m³/s and 800 m³/s in dry years and bias-special dry years;（3） the flow response patterns of Wuzhou flow rate are related to the upstream discharge scale as well as to its changes over time;and（4） large discharge with rapid change may result in short response time.