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开展此项研究是为了测定美国新墨西哥州的两个牧区短期放牧、连续放牧、禁止放牧对土壤侵蚀的影响。本文的土壤侵蚀量是用含沙量和悬移质总量来表示的.经测定.Ft.Stanton 牧区所有放牧处理小区的含沙量都大于禁止放牧区,不同放牧处理之间则没有差异。在 Ft.Sumner 牧区,提高载畜率一倍,并采用短期放牧制度时会导致非常高的含沙量。短期放牧场总的产沙量为适度连续放牧区的两倍。产沙量增加的原因是:由于植被覆盖的减少和裸地面积的增加,降低了地表糙率,破坏了土壤结皮.
The study was conducted to determine the effects of short-term grazing, continuous grazing and no grazing on soil erosion in two pastoral areas of New Mexico, USA. The soil erosion amount in this paper is expressed by sediment concentration and total amount of suspended sediment.It is determined that there is no difference between the grazing treatments in all pasture grazing areas in the Ft.Stanton pasturing area than in the no grazing area. In Ft.Sumner pastures, doubling the stocking rate and using the short-term grazing system can lead to very high levels of sediment. The total amount of sediment produced in short-term grazing land is twice that of a moderately grazing area. The reason for the increase in sediment yield is that due to the reduction of vegetation cover and the increase of bare land area, the surface roughness is reduced and the soil crust is destroyed.