Study On The Influence Of Grassland Soil Nutrien Migration On The Water Quality Of Kherlen River In Different Rainfall Intensities

Kherlen River region is located in the core area of Hulun Buir Grassland and itis an important part.Otherwise, it played a ignored role to protect birds migration,proliferation and vegetation ecological environment security in the north of China.In recent years, grassland soil erosion is becoming more and more serious, thedeterioration of ecological environment is significant, and the rainfall and grazingintensity as the main cause of soil erosion of grassland has been widely concerned byscholars. In this paper, we chose the domestic part of Kherlen River region tostudy.Through the simulation experiment and field experiment in different grazingintensity of rainfall and grassland, studied the erosion of soil and nutrient.Accordingto the test data,analyzed the rainfall, nutrient loss, soil erosion.The results of the study showed that:The grassland runoff process in three grazing intensity of Kherlen River regionwas increased first and then reach to steady.Rainfall runoff was decreased withgrazing intensity increased.Under the same grazing intensity,there was significantpositive linear correlation between the increasing rainfall runoff and the increasingslope.The amount of runoff was: heavy grazing＞light grazing＞No grazing. Therunoff coefficient rule of three kinds of grazing grassland showed that heavy grazing＞light grazing＞No grazing.Sediment and nutrient content in runoff was decreasedwith the runoff time increased gradually and then reached to steady.Under the samegrazing intensity grassland, three kinds of rainfall intensity situation was65mm/h＞45mm/h＞20mm/h in soil erosion and nutrient loss.The amount of runoff, sedimentcontent and nutrient content were in accordance with all relevant binomial in thethree grazing systems of grassland.Three soil water content showed the surface wasmaintained at0.1g/cm3early, but the lower layer was different largely.The shallow infiltration depth was10cm in three kinds of grazing grassland of, the deepest was15cm. The soil moisture content was decreased with the increase of soil depth. It isthe largest that soil water accumulation increased under the20mm/h rain strong inthree kinds of grazing grassland, higher than those of45mm/h and65mm/h.Thecumulative increase of soil moisture in No grazing grassland was greater than theother pastures.