黄土高原森林枯枝落叶层保持水土的有效性

Effectiveness of forest litter to soil and water conservation

采用人工模拟与天然降水相结合的方法 ,定量研究了枯枝落叶层保持水土的有效性。研究结果表明 ,在黄土高原常见坡度 2 5°和暴雨雨强 1～ 2 mm/m in的条件下 ,该地区油松和山杨林枯枝落叶层保持水土的有效厚度为 0 .9～ 1.0 cm,低于这个数量 。

Using the method of artificial simulation combined with natural rainfall,the effectiveness of forest litter to soil and water conservation has been discussed quantitatively in the paper.The results of the study showed that the effective thickness of the litter of P.tabulaeformis and P.davidiana standing for soil and water conservation in the Loess Plateau is 0.9-1.0 cm.The benefits to water storage and sediment reduction will be decreased obviously when litter amount is lower than that thickness.So the protection of litter layer in stand is an important task for forest management in mountain regions.