珠江入海水沙通量变化特征

Analysis on Changes of Discharge and Sediment Load to the Pearl River Estuary

入海水沙通量的近期变化是流域与海岸相互作用研究的焦点和核心内容。本文利用滑动平均法、秩次相关检验和线性回归检验等方法,对控制珠江入海水沙通量的博罗、马口和三水三个水文站1956～2000年的水文资料进行分析。结果表明:珠江入海水沙通量在年内呈季节性变化,4～9月份入海流量分配占全年的74.3～88.8%,含沙量占91.7～96%;三站含沙量在20世纪90年代之后均呈下降趋势,与同期流量比较,博罗、马口含沙量产生突变并呈减少趋势,三水站流量相对同期含沙量则产生突变并呈增加趋势。

It has received widely attention for changes of discharge and sediment load to the estuary in recent years. Based on the measured data of discharge and sediment load of 3 key hydrological stations in the last 50 years （1956 - 2000） in the Pearl River, the flux into the Pearl River esturay was analyzed by non-parameter statistical methods which included the moving average, the Spearman order correlativity and the linear regression analysis. The results were shown as follows ： it has obvious seasonality for changes of discharge and sediment load to the Pearl River estuary. The discharge of April-September to the Pearl River estuary accounts for 74. 3 - 88.8% of the total discharge of the whole year, and the sediment load of April-September accounts for 91.7 - 96% of the total sediment load of the whole year. Meanwhile, there is a decreased trend of the sediment load at Sanshui station to the estuary since 1990s. The changes of the sediment load at Boluo and Makou station had a break with obviously decreased trends compared to the discharge at the same stations respectively. However, at Sanshai station, the discharge had a break with an increased trends compared to the sediment load.