利用连续１７年的流域森林资源和水文资料，分析黑龙江省汤旺河和呼兰河流域森林对河川径流的调节效应，结果表明：（１）森林能使径流年内分配和年际变化趋于均匀，其调节径流能力与森林状况相关；（２）森林覆被率和单位面积蓄积与河川年径流量和年径流系数均呈正相关关系，森林具有增加年径流量和年径流系数的作用，但年径流量和年径流系数主要受年降雨量的影响。

The effects of forest regulating runoff in Tangwang River and Hulan River basins in Heilongjiang Province were analyzed by using 17-year series of forestry and hydrological data. The results were as follows:( 1) forest could make intra-annual distribution and inter-annual variation of runoff uniform. , and the ability of forest regulating runoff increased with the improvement of forest condition ;( 2) forest coverage and unit stock volume were positively correlated with annual runoff discharges and annual runoff coefficient, so forest could increase annual runoff discharges and runoff coefficient in the two rivers, but the influence was not significant.On the other hand , annual precipitation was the main factor which determined the annual runoff discharges and runoff coefficient.