北江流域径流量分布规律及其变异性分析

Analysis on the runaff distribution and the variability in the Beijiang River Basin

以北江流域主要控制性水文站石角站近45年（1956～2000年）径流量序列为基础，分析了北江流域径流变化的基本特征，结果表明径流年内分配不均，年际变化大，年径流量系列呈缓慢上升趋势，并存在2年左右的变化周期，1992年前后发生了一次跃变，但跃变的成因与趋势的成因不一致，趋势与人类活动有关，而跳跃主要受降雨的影响。

Based on the 45 years data of runoff series from the shijiao station that is the main controlling hydrological stationin the Beijiang River Basin, the basic characteristics of runoff variation have been analyzed. The results have shown that the runoff distribution was non-uniform intrayear and big change in years. Recorded runoff at shijiao station had a slow ascending trend, and existed a jump with about 2 years, one jump occurred around 1992, but the causes of trend and jump of runoff were not same. The jump of runoff was major influenced by the precipitation while the trend change was affected by activity of humanitiy.