吉林省长白山区侵蚀沟集水区林业工程治理的研究

Forest engineering on catchment area within erosion gully in Changbai Mountain region of Jilin province

采用林业工程方法治理侵蚀沟集水区,森林覆盖率可由原来的3.0%～11.7%提高到37.1%～93.5%,土壤侵蚀模数由原来的3 352～4 048 t·km-2.a-1下降到1 708～2 148 t·km-2.a-1,下降51%～72%,径流系数减少48.4%,土壤蓄水量增加2 236.1 m3·km-2,土壤湿度提高36%～48%,治理效果显著。无论平缓台地集水区或坡地集水区其影响治理效果的主要因素均为保留农田宽度,保留20 m宽度的农田治理效果最佳;当采用全部还林措施治理时灌木是主要影响因素,乔灌混交林治理效果最佳。

The forest engineering was conducted to restore catchment area within erosion gully in this paper. The restoration effect of this forest engineering was significant, such as the forest coverage increased from 3.0% - 11.7% to 37.1% - 93.5%, the soil erosion modulus decreased 51% -72%, i.e. from 3 352 -404 8 t·km^-2·a^-1to 1 708 -2 148 t ·km^-2·a^-1 , the rl.lnoff coefficient decreased 48.4%, the soil water storage in- creased to 2 236.1 m^3 ·km ^-2, and the soil humidity increased 36% - 48%. The width of farm land was the main factor influencing the restoration of catchment area wherever on mesa or on sloping field. Twenty centimeter was the optimal width for farm land. Shrub was the main factor when forest - return method was applied, and the tree - shrub mixture treatment had optimal effect.