辽河源典型森林类型的土壤水文效应

目的]研究辽河源地区典型森林类型林下土壤的水文效应,为辽河源森林生态系统健康的监测和评价提供理论佐证。方法]选取典型森林类型,采用不同入渗模型拟合各森林类型土壤的入渗过程。结果](1)土壤容重变化范围为1.21~1.56g/cm3,油松中龄林最大,山杨成熟林最小;土壤总孔隙度变化范围为41.26%~54.38%,山杨成熟林最大,油松中龄林最小;(2)山杨成熟林土壤蓄水能力最强,为1 087.56t/hm2;油松中龄林土壤蓄水能力最小,为825.17t/hm2;(3)山杨成熟林稳渗速率最大,为1.33mm/min;(4)霍顿(Horton)入渗模型和菲利普(Philip)入渗模型能较好地反映各森林群落土壤入渗过程,但通用幂函数模型拟合结果较差。结论]不同森林类型土壤均表现出随着土层深度的增加容重逐渐增加的现象,阔叶林林下土壤蓄水能力要强于针叶林,通过比较认为可以利用霍顿(Horton)模型作为研究该区森林土壤水文功能的重要手段。

Soil Hydrological Effects of Typical Forest Types in Upper Reaches of Liaohe River

Objective] Studying the hydrological effects of understory soil of typical forest types in the upper reaches of Liaohe River, aimed to provide theoretical evidence for the monitoring and evaluation of the forest ecosystem health.Methods] The understory soils of some typical forest types were chosen to research their infiltration processes, and upon which the processes were fitted with several permeability models.Results](1) The soil bulk density ranged from about 1.21 g/cm³ to 1.56 g/cm³, the maximum value was found in the middle-aged Pinus tabuliformisforest and maturePopulus davidianaforest had the minimum bulk density. The range of the total soil porosity was 41.26%~54.38%, mature Populus davidiana forest had the maximum porosity and middle-aged Pinus tabuliformis had the minimum porosity; (2) The soil water-holding capacity of mature Populus davidiana forest was greatest with a value of 1 087.56 t/hm² and middle-aged Pinus tabulaeformis forest had the minimum value of 825.17 t/hm²; (3) The steady infiltration rate of mature Populus davidiana forest was 1.33 mm/min; (4) Both Horton infiltration model and Philip model could reflect the soil infiltration course of each forest vegetation well, while the common power functional infiltration performed poorly.Conclusion] The soils of different forest types had greater bulk density in deeper layer. The soil water storage capacity was bigger under broad-leaved forest than that under under coniferous forest. Horton model could be used as an important means to study the local hydrological function of forest soil.