为了保障农田安全和生态型土地整治的顺利进行,以巢湖为研究对象,运用SWAT模型模拟巢湖流域2000—2010年面源污染(总氮、总磷)的空间分布,采用地理加权回归(GWR)模型评估2000—2010年实施的2 609个土地整治项目对面源污染的影响。结果 表明:(1)巢湖流域面源污染恢复与恶化情况并存,总体偏向改善。(2)2000—2005年和2005—2010年面源污染变化区域存在空间差异,与南部地形起伏度高及农业耕作区的空间布局相关。(3)2000—2010年土地整治与面源污染现状R2在0.71～0.74,呈负相关。一方面土地整治中四大工程的实施使得耕地细碎化降低,集约化农业活动也减少了化肥使用量,另一方面,土地整治实施带动了面源污染治理项目落地,使得综合治理效果显著。期望为类似区域开展以面源污染治理为重点的生态景观型土地综合整治提供参考。
In order to ensure the safety of farmland and the smooth progress of ecological land consolidation, Chaohu Lake was taken as the research object. The research used SWAT model to simulate the spatial distribution of non-point source pollution(TN and TP)from 2000 to 2010, and used Geographic Weighted Regression(GWR)model to assess the impact of 2609 land consolidation projects on the non-point source pollution. The results showed that:(1)non-point source pollution in the Chaohu Lake Basin coexisted with recovery and deterioration, and the overall pollution level had decreased;(2)there were spatial differences in the area of non-point source pollution change between 2000—2005 and 2005—2010, which was related to the high terrain in the south and the spatial layout of agricultural farming areas;(3)during the study period, the R2 of land consolidation and non-point source pollution(TN and TP)was between 0.71 and 0.74, which was negatively correlated. On the one hand, the implementation of the four major projects in land improvement has reduced the fragmentation of farmland and the intensive agricultural activities have also reduced the amount of fertilizer use. On the other hand, the implementation of land consolidation has led to the landing of non-point source pollution control projects, resulting in a remarkable effect of comprehensive management. This paper is expected to provide reference for similar areas to carry out ecological land remediation focusing on non-point source pollution control.
