天山林区不同群落土壤水分入渗特性的对比分析与模拟

土壤入渗特性是影响森林生态水文过程的一个重要环节。为了比较不同群落类型土壤水分入渗特性的差异,在天山中段北坡林区利用环刀法测定天然林、人工林、林窗草地、草地、林缘灌木林、山前灌木林六种群落类型的森林土壤入渗过程,对比分析有机质含量、毛管孔隙度、容重、含水率等土壤理化性质对入渗过程的影响,用三种常用模型进行入渗过程模拟,分析比较这/min之间,稳定min之间,不同群落类型土壤平均入渗率从大到小的排序为:天然林林缘灌木林窗草地草地人工林山前灌木;(2)六种群落类型土壤入渗性能均具有初渗速率平均入渗速率稳定入渗速率的相同趋势;(3)Kostiakov模型对试验六种群落类型土壤入渗过程的拟合精度比较高,适用于描述本研究区域水源涵养林地土壤入渗特征;(4)土壤有机质含量与土壤入渗速率呈正相关,且与初始入渗率达到显著水平;土壤的含水率、土壤毛管孔隙度和土壤容重与土壤入渗能力呈现显著的负相关。通过观测与模拟不同群落类型的土壤水分运动过程,本文可为天山林区生态水文长期定位观测提供有益借鉴。

Comparative analysis and simulation of soil moisture infiltration characteristics in different communities in the forests of Tianshan Mountains, China

Soil infiltration characteristic is an important link that affects forest ecological hydrological processes. To compare differences in soil-water infiltration characteristics of different community types, the double cutting ring method was used to analyse natural forests, Artificial forest, gap grasslands, grasslands, forest edge shrubs, and piedmont shrubs on the northern slope of the Tianshan Mountains. The effects of soil physical and chemical properties, such as organic matter content, capillary porosity, bulk density, and water content, on the infiltration process were compared and analysed. Thress common models were used to simulate the infiltration process, and the suitability of these models in the area was analysed and compared. The results were as follows:(1) The initial infiltration rate of the soil in the first 60 min in the six main community types was 2.63-9.00 mm/min, and the stable infiltration rate was 0.85-5.12 mm/min. The average soil infiltration rate of the different community types ranged from high to low as follows:natural forest > forest edge shrub > gap grassland > grassland > artificial forest > piedmont shrub. (2) The soil infiltration performance of the six community types showed the same trend:initial infiltration rate > average infiltration rate > stable infiltration rate. (3) The Kostiakov model had a high fitting precision for the soil infiltration process of the six community types and was suitable for describing the soil infiltration characteristics of the water conservation forests in this study area. (4) The soil organic matter content was positively correlated with the soil infiltration rate and reached a significant level with initial infiltration rate; the soil-water content, soil capillary porosity, and soil bulk density were significantly negatively correlated with soil infiltration capacity. Observation and simulation of the soil-water movement process of different community types can provide a useful reference for the long-term observation of ecological hydrology in the forest areas of Tianshan.