The nutritious balance method and theory by Truog were used to estimate the main source of agri-cultural non-point source pollution

i.e.

the total excessive nitrogen

and outline the changing trend on the relation of rural resident′s consumption level to agricultural excessive nitrogen pollution in Jiangsu Province by compiling Jiangsu Province′s agricultural production data in 1990-2007. Based on the stationarity test analysis of time series data

the simulating model projected that the correlation of excessive nitrogen emission to per capita consumption was well fitted by a cub-regression curve.Results indicated that:(1)Nitrogen in Jiangsu Province′s agricultural production has been excessive since 1990. In 2007

the total excessive nitro-gen reached as high as 1.487 million tons

8.38 times of that in 1990. Per capita living consumption of rural residents increased from 787yuan in 1990 to 4792 yuan in 2007

with an average annual increase rate of 11.6% over the 17 years. (2)The study supported the evidence that the environmental Kuznets curve(EKC) was a possibility rather than a necessity

which had various forms

different turning points

and different time spans to the turning point appearance in different countries and regions. (3)The simulated correlation curve did not fully meet the standards of the EKC

or rather it showed N curve characteristics. In the end

we proposed that the governments should actively provide farmers with the guidance on the rational applica-tion of fertilizer

improvement of fertilizer use efficiency

and controlling agricultural non-point source pollu-tion through the development of efficient ecological agriculture and recycling agriculture.