The Distribution of Nitrogen in Soil and Rainfall Intensity on Nitrogen Infiltration Flux Influence in Partly Saturated Soil

Combined with the transformation theory of nitrogen in soil, this paper describes the distribution of nitrate nitrogen in the soil and analyses the effect of rainfall intensity rate on infiltration and run-off experienced by a partly saturated soil slope and soil column during rainfall. Based on the rainfall and artificial rainfall experiments under the simulated rainfall and water-level-controlled field conditions and measurement, the undisturbed soil column and groove is built and the flux of nitrate nitrogen and its infiltration rate and run-off responses are simulated. The influence of the rainfall intensity and pattern of rainfall on the nitrogen infiltration of a soil is investigated and simulated. The results obtained is the proportion of the nitrate nitrogen stored in large holes and small pores lies on the structure of the soil and the water content and its infiltration flux is influenced by rainfall intensity greatly especially in partly saturated soils. And if ignoring big holes nitrate nitrogen influence, its transport flux is power function relation with water content of per area soil. The research provides references for non-point source pollution modeling, soil pollution prevention and water quality management.