冀北山地不同坡位油松林土壤水文效应

Soil hydrological effects of Pinus tabulaeformis forest at different slope positions in the northern mountain of Hebei Province

对冀北山地不同坡位油松林土壤层水文效应进行初步研究,结果表明：（1）0~40cm土层内,土壤容重的变动范围在0.97~1.19g/cm3,土壤总孔隙度的变动范围在45.43%~54.50%,土壤容重随土层深度的增加而增大,总孔隙度随土层深度的增加而减小;（2）坡上样地Ⅱ和样地Ⅰ每10cm饱和持水量最大,分别为713.67t/hm2和708.56t/hm2,坡中样地Ⅲ饱和持水量最小,仅为583.00t/hm2,坡中样地Ⅲ和坡下样地Ⅳ每10cm土壤的有效持水量最大,分别为196.33t/hm2和185.00t/hm2,坡上样地Ⅱ有效持水量最小,仅为74.67t/hm2;（3）林下土壤初渗速率在76.09~20.81mm/min,稳渗速率在1.95~4.06mm/min,入渗速率与入渗时间存在明显幂函数关系。

The preliminary study on the hydrological effect in the soil layer of Pinus tabulaeformis forest at different slope positions in the northern mountain of Hebei Province was conducted.The results showed that：（1）in the soil layer of 0-40 cm,the variation range of soil bulk density was 0.97-1.19g/cm3,which increased with soil depth,and the soil total porosity was 45.43%-54.50%,which decreased with the soil depth;（2）the saturated water content per 10 cm of Plot II and Plot I at the upper slope was the maximum,with 713.67t/hm2 and 708.56t/hm2,respectively,while that of Plot III at the mid slop was the smallest,only with 583.00t/hm2.The soil effective moisture per 10 cm of Plot III at the mid slope and of Plot IV at the lower slope was the maximum,with 196.33t/hm2 and 185t/hm2,respectively;while that of the Plot II at the upper slope was the minimum,only with74.67t/hm2;（3）the soil initial infiltration rate under the forest was 76.09~20.81 mm/min,with the steady infiltration rate of 1.95~4.06 mm/min.There existed an obvious functional relationship between infiltration rate and infiltration time.