坡度和降雨强度对坡耕地入渗的影响

Influence of Slope Gradient and Rainfall Intensity on Infiltration in Sloping Farm Land

利用人工模拟降雨对黑龙江西部半干旱区坡耕地不同坡度和不同降雨强度下的土壤水分入渗规律进行了试验研究,采用产流历时和稳定入渗速率二项指标进行分析,发现随着地面坡度的增大,产流历时提前,稳定入渗速率逐渐减小,坡面产流历时与坡度呈对数函数关系,土壤稳渗速率与坡度呈幂函数关系;随着降雨强度的增大,产流历时提前,稳定入渗速率逐渐增大;坡面产流历时与降雨强度呈指数函数关系,土壤稳定入渗速率与降雨强度也呈指数关系。

The infiltration regularity in sloping farm-land in the west semiarid region Heilongjiang province was studied by means of artificial rainfall method under different slope gradient and different rain intensity condition. Using the two indexes of runoff starting time and steady infiltration rate, the infiltration features of the soil were analyzed. The results show that runoff starting times were earlier and the steady infiltration rates decreased with the land-slopes increasing; there was a logarithm function relation between the runoff starting time and the land-slope, and a power function relation between the steady infiltration rate and the land-slope; the runoff starting times were earlier and the steady infiltration rates increased with the rain intensities increasing; there was a index function relation between the runoff starting time and the rain intensities, and the relation between the steady infiltration rate and the＇rain intensity can be also expressed in a index function.