森林经营方式对不同林龄落叶松林枯落物及土壤水源涵养能力的影响

Effects of Forest Management Methods on Litter and Soil Water Conservation Capacity of Larix principis-rupprechtii Plantation of Different Ages

研究森林经营方式对不同林龄落叶松林林下枯落物及土壤水源涵养能力的影响,为该研究区落叶松人工林经营与水土保持措施的制定提供理论依据。2021年8月在赤峰市旺业甸林场选取近自然经营、常规经营和未经营措施下的落叶松幼龄林、近熟林和成熟林为研究对象,采用野外调查取样与室内实验分析相结合的方法,对比分析不同经营方式下落叶松幼龄林、近熟林和成熟林林下枯落物与土壤的持水能力,并运用熵权法对落叶松林枯落物及土壤水源涵养能力进行综合评价。结果表明,9种样地类型枯落物总厚度介于2.37~5.83 cm,总蓄积量介于11.27~37.07 t/hm^(2),不同林龄落叶松林林下枯落物最大持水量和有效持水量的变化趋势由大到小顺序均为成熟林、近熟林、幼龄林;不同经营方式落叶松林林下枯落物最大持水量和有效持水量由大到小顺序均为未经营、常规经营、近自然经营;不同林龄落叶松林林下土壤总孔隙度、毛管孔隙度、饱和持水量和毛管持水量的变化规律由大到小顺序均为幼龄林、成熟林、近熟林;不同经营方式落叶松林林下土壤孔隙度及持水量的变化规律由大到小均为近自然经营、常规经营、未经营;落叶松林在未经营措施下成熟林阶段林下水源涵养能力最高,在常规经营措施下幼龄林阶段林下水源涵养能力次之,在常规经营措施下近熟林阶段林下水源涵养能力最低。

The effects of forest management methods on the understory litter and soil water conservation capacity of Larix principis-rupprechtii forests of different ages were studied to provide a theoretical basis for the formulation of Larix principis-rupprechtii plantation management and soil and water conservation measures in the study area.In August 2021,young forests,near-mature forests and mature forests of Larix principis-rupprechtii under near-natural management,conventional management and non-management measures were selected as the research objects in Wangyedian Forest Farm,Chifeng City,the method of field survey and sampling combined with indoor experimental analysis was used to compare and analyze the water holding capacity of understory litter and soil in young Larix principis-rupprechtii forest,near-mature forest and mature forest under different management methods,and the entropy weight method was used to comprehensively evaluate the litter and soil water conservation capacity of Larix principis-rupprechtii forest.The results showed that:the total thickness of litter in 9 sample plots ranged from 2.37 cm to 5.83 cm,and the total volume of litter ranged from 11.27 t/hm 2 to 37.07 t/hm^(2).The maximum and effective water holding capacity of litter under different ages of Larix principis-rupprechtii forests showed the trend of mature forest>near-mature forest>young forest.The maximum and effective water holding capacity of litter under Larix principis-rupprechtii forest under different management modes showed the order of non-management>conventional management>near natural management.Soil total porosity,capillary porosity,saturated water capacity and capillary water capacity under different ages of Larix principis-rupprechtii stands had the regularities of young forest>mature forest>near-mature forest.Soil porosity and water holding capacity of Larix principis-rupprechtii forest under different management patterns showed the change rule of near-natural management>conventional management>non-management.Under non-management measures,the understory water conservation capacity of mature forest stage of Larix principis-rupprechtii forest was the highest;under conventional management measures,the understory water conservation capacity of young forest stage was second,and the understory water conservation capacity of near-mature forest stage under conventional management measures was the lowest.