冀北山地5个海拔梯度油松林枯落物与土壤水源涵养功能研究

Study on Litter and Soil Water Conservation Function of Pinus tabulaeformis Forests at 5 Altitudinal Gradients in Mountains of Northern Hebei

为了研究冀北山地5个海拔梯度(910,1 050,1 160,1 320,1 450 m)油松(Pinus tabuliformis)纯林水源涵养功能,利用浸泡法对林分的枯落物层的持水量与拦蓄能力进行了研究,利用环刀法和双环法对土壤层蓄水能力进行了研究,结果表明:枯落物总蓄积量、最大持水量、有效拦蓄能力变化规律一样,均随海拔升高先减小后增大,最大持水率随着海拔的升高呈现增大的趋势,总蓄积量变动范围为32.14～41.97 t/hm^2,最大持水量为67.31～103.95 t/hm^2,有效拦蓄能力为48.16～84.69 t/hm^2,最大持水率范围为196.85%～253.34%,枯落物持水量、吸水速率与浸泡时间有较好的拟合关系,R>0.96。土壤容重随海拔升高先增大后减小,变化范围为0.96～1.20 g/cm^3,总孔隙度随海拔升高先减小后增大,土壤层有效持水量随海拔升高而减小,土壤入渗速率与入渗时间呈明显幂函数关系,R>0.92。

In order to study the water conservation function of Pinus tabuliformis in five elevation gradients(910 m, 1 050 m, 1 160 m, 1 320 m, 1 450 m) in the northern Hebei, the immersion method was used to control the litter layer of the stand. The water volume and capacity of the storage of litter were studied, and the water storage capacity of the soil layer was studied by the ring method and the double ring method. The results showed that the total accumulation of litter, the maximum water holding capacity and the change of the effective retention capacity were the same as the elevation the increases, and the maximum water holding rate increased with the increase of elevation, and the total volume change ranged from 32.14 t/hm^2 to 41.97 t/hm^2, the maximum water holding capacity ranged from 67.31 t/hm^2 to 103.95 t/hm^2, and the maximum water holding capacity was effectively blocked. The maximum available water holding ranged from 48.16 t/hm^2 to 84.69 t/hm^2, the maximum water holding rate ranged from 196.85% to 253.34%, the water holding capacity of litter, water absorption rate and soaking time had the better fitting relationship(R>0.96). The soil bulk density increased first and then decreased with the increase of elevation, and the range of change was 0.96~1.20 g/cm^3. The total porosity decreased first and then increased with the increase of elevation. The effective water holding capacity of soil layer decreased with the increase of elevation, and relationship between the soil infiltration rate and infiltration time could be described by the power function(R>0.92).