宁夏罗山自然保护区3种典型林分凋落物和土壤层水源涵养能力综合评估

森林凋落物层和土壤层是森林生态水文效应中的主要贡献层，对森林生态系统水土保持功能和水源涵养能力有重要影响。对比宁夏罗山自然保护区3种典型林分类型凋落物和土壤层水文效应的变化规律和水源涵养能力大小，为该地区的森林生态水文、水土保持和森林管理提供科学依据。以该自然保护区青海云杉纯林、油松纯林和青海云杉油松混交林为研究对象，运用称量、室内浸泡、环刀法和回归分析法对凋落物和土壤层的水文效应进行测定和拟合，并使用熵权法对二者的水源涵养能力进行评估。结果表明：（1）青海云杉油松混交林凋落物的总厚度和总储量显著高于青海云杉纯林和油松纯林（P<0.05），3种林分类型的半分解层的厚度和储量高于未分解层。（2）凋落物层最大持水量范围为63.29-95.08t/hm²，最大持水率范围为335.97%-353.85%，有效拦蓄量范围为34.09-63.92t/hm²，三者均为青海云杉油松混交林>云杉纯林>油松纯林。（3）3种林分类型的凋落物持水量（Q）与浸泡时间（t）呈对数函数关系，吸水速率（V）与浸泡时间（t）呈幂函数关系。（4）从3种林分类型的土壤物理性质和持水特性得出，3种林分类型的土壤层水文效应的等级排序为云杉油松混交林>油松纯林>青海云杉纯林。（5）凋落物层和土壤层的水源涵养能力大小为青海云杉油松混交林（0.43）>油松林（0.3）>青海云杉林（0.27）。综合来看，青海云杉油松混交林的凋落物层和土壤层的水源涵养能力最优，其次是纯林，说明混交林在水土保持和水源涵养方面比纯林更具优势。

Comprehensive evaluation of the water conservation capacity of litter and soil layers in three typical forest types in the Luoshan Nature Reserve, Ningxia

The litter layer and soil layer are the main contributing layers to the forest eco-hydrological effects, significantly influencing the water and soil conservation functions and water storage capacity of forest ecosystems. This study compares the variations and water conservation capacities of litter and soil layers among three typical forest stand types in the Luoshan Nature Reserve, Ningxia, China, providing a scientific basis for forest eco-hydrology, soil and water conservation, and forest management in the region. The study focuses on pure forests of Qinghai spruce, pure forests of Chinese pine, and the mixed forests of Qinghai spruce and Chinese pine. Measurement, laboratory soaking, ring knife method, and regression analysis are employed to determine and model the hydrological effects of litter and soil layers. The entropy weight method is used to assess their water storage capacities. The results indicate that:(1) the total thickness and total storage of litter in the mixed forest of Qinghai spruce and Chinese pine are significantly higher than those in the pure forests of Qinghai spruce and Chinese pine (P<0.05), and the thickness and storage of the semi-decomposed layer are higher than those of the undecomposed layer in all three forest stand types. (2) the maximum water-holding capacity of the litter layer ranges from 63.29 to 95.08t/hm², with a maximum water-holding rate ranging from 335.97% to 353.85%, and the effective water retention ranges from 34.09 to 63.92t/hm². In all three forest stand types, these values follow the order of mixed forest of Qinghai spruce and Chinese pine>pure Qinghai spruce forest>pure Chinese pine forest. (3) the litter water-holding capacity (Q) of the three forest stand types exhibits a logarithmic function relationship with soaking time (t), while the water absorption rate (V) shows a power function relationship with soaking time (t). (4) the ranking of hydrological effects of soil layers among the three forest types, based on their physical properties and water holding characteristics, is spruce and pine mixed forest>pure pine forest>pure spruce forest. The water conservation capacities of the litter layer and soil layer are in the order of spruce and pine mixed forest (0.43)>pine forest (0.3)>spruce forest (0.27). Overall, the water conservation capacity of the litter layer and soil layer is the best in the spruce and pine mixed forest, followed by the pure forests, indicating that the mixed forests have greater advantages in soil and water conservation than pure forests.