Abstract:

In order to explore the rule of N, P migration and transformation in paddy soil and its influence on the quality of surface water in karst hilly regions of Central Guizhou Province. The concentration of N and P in surface water of paddy field and its correlation with the contents of N and P in paddy soil were analyzed. The results showed that, the content of total nitrogen (TN), ammonium nitrogen (NH4+-N) and nitric nitrogen (NO3--N) in surface water of paddy field were 1.39-15.81 mg/L, 0.57~13.35 mg/L and 0.15-1.37 mg/L, respectively, which the concentrations of TN, NH4+-N and NO3--N were correlated with content of soil available nitrogen, in some extent. The concentration of total phosphorus (TP) was 0.046-0.324 mg/L, which the concentration of TP was significantly correlated with content of soil available phosphorus. The concentration of TN and NH4+-N in surface water of paddy field exceed the limits of the Class Ⅴ water body, the nitrogen migration caused by farmland drainage from paddy field had a significant impact on the surrounding surface water quality.