Effect on nitrogen output in farmland with different nitrogen fertilization
施用不同氮肥对坡耕地径流中N输出的影响

It was conducted to determine the effect of fertilizing to nitrogen loss by testing the nutrient loss from the farmland in natural rainfall events. The sloping field was selected to conduct the research in the northeast of Taian, Shandong Province. The results showed that the concentrations of N in the surface runoff were increased sharply, and the mass of N loss during precipitation runoff were also high. Under the same fertilizer level, CR-urea could reduce nitrogen 15 %-25 % loss availably, comparing with NH4HCO3 and usual urea. In the same time, 70% nitrogen loss was occurred in the early stage of rainfall events. Reducing the amount of nitrogen by rational fertilization in the surface of the soil was a key method to decrease the nitrogen loss.