Effect of horizontal stage on vertical redistribution of the soil water N and P Oil the sloping land
坡耕地反坡水平阶对土壤水N、P垂直再分配的影响

Combined field observation and laboratory experiment,the Nitrogen and Phosphorus in the soil water of horizontal stage in water source area of Songhuaba reservoir in Kunming were analyzed.The results indicated that TN,NH＋4-N,NO-3-N and TP had significant difference in the soil water of two treatments in soil layer from 20 cm to 40 cm,TN and NH＋4-N had significant difference from 40 cm to 60 cm.The four nutrient mentioned of soil water hadn＇t significant difference in two treatments,but hadn＇t significant difference from 60 cm to 100 cm.In soil layer from 20 cm to 40 cm,the correlation coefficients of TN,NH＋4-N concentration of soil water and TN content of soil were 0.94（P0.05） and 0.97（P0.01）,and the correlation coefficients of TP concentration of soil water and TP,AP content of soil were 0.90（P0.05） and 0.98（P0.01）.The correlation coefficient of TN concentration of soil water and TN content of soil was 0.92（P0.05）,and the correlation coefficient of TP concentration of soil water and AP content of soil was 0.96（P0.01） in soil layer from 40 cm to 60 cm.The correlation coefficients of NO-3-N concentration of soil water and TN,AN content of soil were 0.90（P0.05） and 0.92（P0.05）,and the correlation coefficient of TP concentration of soil water and AP content of soil was 0.93（P0.05） in soil layer from 60 cm to 80 cm.The correlation coefficient of NO-3-N concentration of soil water and AN content of soil was 0.94（P0.05） in soil layer from 80 cm to 100 cm.Results show that runoff of the sloping land could change effectively into subsurface flow by reverse-slope terrace,N and P concentration of soil water tended to increase in varying degrees in soil layer from 20 cm to 100 cm.Accumulation of N and P of soil were caused by the movement of N and P in soil layers.