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Jilin Province is one of China's major commodity grain production bases, application of about 2.038 million tons of fertilizer years, the average amount of chemical fertilizer to 34.9 kg / acre, higher than the national average, and the world average. Retired farmland water surface runoff import the tributaries into the main stream exacerbated watershed non-point source pollution contribution. Compared with other regions of the country, Jilin Province, there are many aspects of climate, topography and hydrology, soil type, and economic development status of its own characteristics, which determines the non-point source pollution has very distinctive features. To do this, carry out agricultural non-point source pollution is important to study. In this paper, the source area in Jilin Province, Liaohe typical watershed - Quan small watershed on Runoff different farming methods and the slope, the loss of nitrogen, phosphorus characteristics, application AnnAGNPS model simulation Quan Small Watershed nitrogen, phosphorus loss concluded as follows: (1) set of experimental cell were: 4.8 ° bare land, 5.2 ° horizontal terraced fields, 5.5 ° downslope ridge, 6.5. General planting. By analyzing the concentration of nitrogen and phosphorus in times of rainfall with surface runoff losses, the results show that nitrogen is usually the loss of soluble nitrogen; phosphorus loss in particulate form. Different farming methods, slope, nitrogen, phosphorus loss variation of 5.5 ° downslope ridge gt; to 4.8 ° bare gt; to 6.5 ° general planting gt; 5.2 ° horizontal terraced fields. Different rainfall runoff, farmland farming methods and slope, the impact of the loss of the amount of nitrogen and phosphorus. Greater rainfall runoff, nitrogen and phosphorus losses faster; steeper the slope, the higher the load of nitrogen and phosphorus pollution; farming methods more complex, the smaller of nitrogen and phosphorus pollution load. (2) will be in the river on the Liaohe River headwaters area the typical watershed - Quan small watershed through March 2009 to October, Quan Ho rainfall runoff process ammonia nitrogen, total phosphorus pollution loss characteristics and pollutant output law, its The monitoring results show that the summer of nitrogen, phosphorus loss from large in spring than fall, the amount of nitrogen and phosphorus loss increases with increasing rainfall. (3) AnnAGNPS model can simulate the rainfall conditions, nitrogen and phosphorus pollution load. Ammonia nitrogen, total phosphorus measured values ??and model simulation, the deviation of the ammonia analog value is less than the total phosphorus. To verify the feasibility of the application of the model in the source area of ??Liaohe. Based on the above research foundation, Liaohe source of agricultural non-point source pollution control program.
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