[Simulation and Motivation Analysis of Agricultural Nitrogen Non-point Source Pollution in North Intensive Farming...

Understanding the patterns and drivers of agricultural non-point source pollution is crucial for regional ecological governance. Here, we focused on simulating non-point source nitrogen pollution in agricultural areas of the north intensive farming area. Utilizing the InVEST model, ArcGIS hot spot analysis tool, and geodetector, we deeply analyzed the sources, loss loads, key source areas, and driving factors of agricultural non-point source nitrogen pollution from 2000 to 2020. The results showed that： ① Agricultural nitrogen input intensity in the north intensive farming area exhibited a decreasing trend from 2000 to 2020, with a spatial pattern of "low in the north and high in the south," primarily driven by nitrogen fertilizer application and livestock breeding. ② Nitrogen emission intensity in each city decreased significantly over the study period, showing an overall spatial pattern of "low in the northwest and high in the southeast." ③ The scope of key source areas experienced a shift from initial narrowing to subsequent expansion. ④ Rainfall emerged as the primary driving force influencing the spatial variation in agricultural nitrogen emission intensity, with its interaction with DEM and slope further accentuating the differentiation. The results of this study can provide a scientific basis for regional agricultural environmental protection policies, thereby promoting the healthy and sustainable development of the agricultural ecosystem.