Taking a regular bare slope with red soil as control

the reduction effects of grass planting belt onthe non-point source pollutants from red soil sloping cropland were studied by simulating the quantities ofrunoff

sediment

nitrogen

phosphorus and the erosion processes under the different rainfall intensity conditions integrated with different concentrations of nitrogen

phosphorus and other non-point source pollutantspreset by the data observed in the field.Results showed that the reduction effects on runoff and soil weremore obvious when rainfall intensity was low.The soil reduction effect was more remarkable than the runoffreduction effect under the same rainfall intensity condition.Compared with the bare red soil area

the reduction rate of the total nitrogen(TN)by the grass planting belt was decreased with increases in both rainfall intensity and the input of the TN.The reduction rate of the total phosphorus(TP)by the grass planting beltwas increased with the input increment of the TP under 20and 35mm/h rainfall intensities.When the inputconcentration of the TP was stable

the reduction rate of the TP by the grass planting belt was decreasedwith the increment of rainfall intensity.When rainfall intensity reached 50mm/h

the output of the TN inrunoff from the grass planting belt plot was more than that from the bare red soil plot.