原始红松林和次生白桦林降雨截留分配效应研究

 以小兴安岭原始红松林为研究对象,通过97场的降雨测定,对原始红松林的降雨截留分配效应进行系统研究。结果表明:原始红松林在生长季内的林冠截留量为98.68 mm,占同期降雨量的19.61%,是次生白桦林的1.3倍。与全国其他森林类型的平均林冠截留率（11.4%～36.5%）相比,原始红松林的林冠截留率处于中等水平。原始红松林在生长季内的穿透雨量和树干径流量分别为395.77和8.78mm,分别占同期降雨量的78.65%和1.74%。与次生白桦林相比,其穿透雨量减少,而树干径流量增加。统计分析表明,原始红松林的林冠截留量、林内穿透雨量和树干径流量与林外降雨量之间均呈现紧密的三次多项式函数关系（p<0.01）,而次生白桦林的林内穿透雨量与林外降雨量之间却呈现良好的直线关系（p<0.01）。最后,对影响林内穿透雨和树干径流的因子进行筛选和分析,为研究针阔混交林的降雨分配效应提供重要参考。

Rainfall redistribution in virgin Pinus koaiensis forest and secondary Betual platyphylla forest in Northeast China

The Pinus koraiensis virgin forest in Xiaoxing'an Mountains was selected to study its rainfall redistribution effect via 97 rainfall events in a growing season.The following results were concluded: 1) the canopy(interception) of the Pinus koraiensis virgin forest amounted to 98.68mm,which was 19.61 percent of the total rainfall and 1.3 times of that in secondary Betula platyphylla forest.Compared with other forest type in China the ratio of the canopy interception of Pinus koraiensis virgin forest was in a middle level.2) the throughfall and stemflow of the Pinus koraiensis virgin forest was respectively 395.77?mm and 8.78?mm,equaling to 78.65% and 1.74% percent of rainfall and the former was lower and the later higher than the secondary Betual platyphylla forest.3) the cubic regression equations describing the relation between throughfall,stemflow and canopy interception of the Pinus koraiensis virgin forest and the rainfall in open field were fitted but a linear regression equation was fitted between the throughfall of Secondary Betual platyphylla forests and the open rainfall.In this paper,the factors influencing throughfall and stemflow were analyzed and selected,thus important references were provided to study the rainfall redistribution effect of coniferous and broad-leaved mixed forest.