海子流域土壤物理特性及其水源涵养能力分析

Analysis of Soil Physical Properties and Capacity of Water Conservation in Haizi Watershed

为了研究宁夏海子流域水源涵养林下土壤的水源涵养能力,采用野外实地采样和室内环刀法测定分析6种林分类型10块林地的土壤容重、孔隙度、田间持水量、渗透性和土壤蓄水量等指标。研究结果表明:2016年海子流域水源涵养林10块林地的表层(0~20 cm)土壤的平均容重最小,为1.35 g/cm^3,中层(20~40 cm)和下层(40~60 cm)平均容重分别为1.55 g/cm^3和1.48 g/cm^3;天然次生林地的表层土壤容重小于人工林地的;天然次林地的表层土壤总孔隙度和非毛管孔隙度较人工林地的高;阴坡植被土壤的平均土壤稳渗率大于阳坡的;人工林土壤中层的渗透性大于表层的;同种植被不同影响因素下的土壤蓄水容量不同,油松林4(3 050.56 t/hm^2)>油松林3(2 946.60 t/hm^2)>油松林2(2 903.47 t/hm^2)>油松林1(2 608.53 t/hm^2),刺槐林2(3 155.93 t/hm^2)>刺槐林1(2 660.64 t/hm^2);10块林地的平均土壤蓄水容量为2 772.16 t/hm^2,平均土壤有效蓄水容量为524.05 t/hm^2。

In order to research the soil capacity of water conservation in water conservation forests in Haizi watershed,this paper researched soil hydrology indexes on 10 woodlands of six stand types,including soil bulk density,porosity,field capacity,permeability and soil water storage capacity by using the field sampling and indoor cutting ring method. The results show that the average soil bulk density is 1.35 g/cm^3 at the layer of 0-20 cm,1.55 g/cm^3 at 20-40 cm and 1.48 g/cm^3 at 40-60 cm in 2016. Soil bulk density on natural secondary forest land is less than that on the artificial one. Soil total porosity and soil non-capillary porosity on natural secondary forest land are less than those of the artificial ones. The average soil solid permeability in shady slope is higher than that in sunny slope. The soil permeability in the middle layer is higher than that in surface on the artificial forest. Soil water storage capacity under different influencing factors of same vegetation are different,Chinese pine forest 4( 3 050.56 t/hm^2) > Chinese pine forest 3( 2 946.60 t/hm^2) > Chinese pine forest 2( 2 903.47 t/hm^2) > Chinese pine forest 1( 2 608.53 t/hm^2),Locust forest 2( 3 155.93 t/hm^2) > Locust forest 1( 2 660.64 t/hm^2). Soil water storage capacity of 10 woodland is 2 772.16 t/hm^2 while the average effective soil water storage capacity is 524.05 t/hm^2.