Abstract: The nutrient balance can be served as an effective indicator of the environment performance of agricultural production.To estimate environmental impacts of agriculture production in Zhejiang Province, temporal trend of nutrient input, use efficiency and surplus intensity, together with the regional difference in nutrient surplus among cities, were analyzed based on agricultural data derived from statistic yearbook from 2000 to 2014. Chemical fertilizer was the primary source of nutrient input. The nitrogen (N) input intensity basically remained stable, while the phosphorus (P) input intensity increased by20.5%.Simultaneously, the N use efficiency increased by 1.4%, while the P use efficiency decreased by 17.5%. The average use efficiencies of N and P were low and had a value of 0.36 and 0.28, respectively. Results of GIS and temporal trend analyses showed that pollution risk of P input was higher than that of N in terms of risk magnitude andinfluence sphere. Jinhua and Wenzhou suffered the most from nutrient surplus, and Huzhou was the only city exhibiting significant positive trends of both N and P surplus ratios. This work suggests that reduction in chemical fertilizer application and enhancement of nutrient use efficiency, should help reducing the risk of non-point source pollution. Reduction of P input and nutrient management in key areas such as Jinhua, Wenzhou and Huzhou should be given higher priority. This work provides more targeted evidence of agricultural non-point source pollution control in Zhejiang Province.
Key words：nutrient balance; nutrient use efficiency; agricultural non-point source pollution; spatial analysis; time-series trend analysis