黑龙江省东部森林中雪的水文效益的初步研究

A PRELIMINARY STUDY ON HYDROLOGICAL EFFECTS OF SNOW IN THE FOREST OF EAST HEILONGJIANG

为了定量研究雪的水文过程．采用冬季野外直接观测法，研究森林对降雪、截雪、积雪、融雪的影响及森林融雪径流的特点。结果表明，森林的截雪率与林冠郁闭度关系密切．针叶林的截雪率是落叶林的２～３倍；人工红松林内积雪厚度最小，融雪持续的时间最长，而落叶杂木林内积雪厚度最大、融雪持续的时间较短，针阔混交林则介于二者之间；天然次生林的融雪径流占年径流量的２１．７％，河道径流主要以降雨径流补给为主、占年轻流量的７０％以上，森林融雪径流的大小主要取决于林内积雪量的大小；融雪径流一般从４月初开始到５月底结束，在４月下旬达到最高峰；降雪有助于森林养分的积累。

The hydrological effects of snow in different forest types in east of Heilongji-ang were studied. especially the influence of forest on snow. snowinterceptionsnowaccumulation, snowmelt and snowmelt runoff. The results showed that therelationship between snowinterception and capnopy density closed even more. The rate of snowinterception through coniferous forests was about two-three times more than that through deciduious broadleaved forests. Snowcover in the korean pine plantation was low but duration of snowmelt was long. In the deciduious broadleaved forest. snow cover was high, but duration of snow melt was short.That of the mixed coniferous and deciduous forest was in the middle. The snowmelt runoff in the natural secondary forest was 21. 7% of the annual runoff.Streamflow that was mainly supplied by rainfall was more than 70% of the annualrunoff. Snowmelt runoff in a forest region most depended on snow-accumulation in a forest. The duration of snowmelt runoff that began in the early of April and ended in the end of May and reached the peak in the end of April was about two months. Snow was favourabe to the accumalation of forest nutrient.