Abstract: The effects of grazing rate on the soil saturated hydraulic conductivity and its spatial variation were investigated in a grazing trial which began in 1990 at Baiyinxile Rancho,Inner Mongolia.China.The stocking rate were 0,1.33,2.67,4.0,5.33,6.67 sheep unit/ha and rotation grazing treatn1ent was conducted.The saturated hydraulic conductivity between two adjacent points,with separation distance of 2m or above in all directions are independent.The saturated hydraulic conductiviy was in-normally distributed and all data were natural logarithmically transformed be fore statistical analysis.Grazing had significant effects on soil saturaed hydraulic conductivity(p=0.003 of one way analysis of variance)and its standard deviation(p=0.004 of one way analysis of variance).The soil saturated hydraulic conductivity decreased with the increasing of stocking rate,and the two demonstrated significant regression relation.The regression equation was Y=e^{-2.72-0.0822x},where Y was saturated hydraulic conductivity in mm/second and X was stocking rate in sheep unit/ha.The stocking rate and the spatial variation of saturated hydraulic conductivity did not lead a linear relation.

Key words: Grazing, Stocking rate, Soil saturated conductivity

摘要： 本文研究放牧对土壤饱和导水率及其对饱和导水率空间变异的影响。结果表明,在2m及2m以上相邻两点之间土壤饱和导水率相互独立,在各个方向均如此。呈自然对数正态分布。放牧对饱和导水率和饱和导水率的标准差有极显著的作用,一元方差分析p=0.003和0.004。随着放牧率的增大,饱和导水率降低,与放牧率呈极显著的回归关系。回归方程为Y=e^{-2.72-0.0822x},其中Y为饱和导水率(mm/s)·x为放牧率(羊/hm²)。随着放牧率的增大,土壤饱和导水率的变异程度并未出现趋势性的变化。

关键词: 放牧, 放牧率, 土壤饱和导水率