论文部分内容阅读
选取三峡库区典型流域,利用已校准的连续非点源污染模型AnnAGNPS,评价作物种植、化肥施用水平和3组农业管理措施(保护性耕作措施,CTP;保护性工程措施,CRP;退耕还林措施,CCFP)对农业非点源污染(NSP)输出的削减效果.模拟结果表明:作物种植类型对泥沙削减的效果差异不显著,对磷输出削减的效果差异显著;化肥施用量对总氮和总磷输出影响极显著;CTP可以显著削减泥沙输出,增加养分输出;CRP能削减泥沙输出,对养分输出削减的效果不显著;CCFP对泥沙和养分输出削减效果均显著,坡度>10°农田实施CCFP后,流域泥沙输出<5t.hm-2,氮、磷等养分输出量可降低至容许范围.
The typical watersheds in the Three Gorges Reservoir Area were selected to evaluate the effects of crop cultivation, chemical fertilizer application and three sets of agricultural management measures (conservation tillage measures, CTP; protective engineering measures, CRP) on the basis of AnnAGNPS, a calibrated continuous non-point source pollution model (CCFP) on agricultural non-point source pollution (NSP) output.The simulation results show that: the effect of crop planting type on sediment reduction is not significant, and the effect of reducing phosphorus output is significant; CTP can significantly reduce sediment output and increase nutrient output; CRP can reduce sediment output, which has no significant effect on nutrient output reduction; CCFP has significant effects on reducing sediment and nutrient output, with a slope> After the implementation of CCFP at 10 ° of farmland, the sediment output of the watershed is less than 5t.hm-2. The output of nutrients such as nitrogen and phosphorus can be reduced to the allowable range.