Research on Characteristics and Influencing Factors of Rural Domestic Sewage Generation and Discharge in the Yellow River Basin at County Level

This study integrates geostatistical analysis, correlation analysis and pollution load assessment to investigate the spatial distribution characteristics and environmental impacts of rural domestic pollution emissions in the Yellow River Basin, laying a foundation for the sustainable development of rural areas and zoned and classified management of rural domestic sewage in the basin. Results show that: ① The average rural domestic sewage discharge coefficient in the basin is 25.67 L/(person·day), and the average pollutant generation coefficients are as follows: chemical oxygen demand (COD) 23.08 g/(person·day), ammonia nitrogen (NH3-N) 0.71 g/(person·day), total nitrogen (TN) 1.29 g/(person·day) and total phosphorus (TP) 0.11 g/(person·day); ② Rural sewage discharge coefficients near urban areas are higher than other rural areas in the same jurisdiction, with downstream areas significantly exceeding upstream non-urban areas; ③ Youth population, illiterate population, average education years and annual precipitation are key influencing factors, showing significant negative correlations with the former two and positive correlations with the latter two; ④ The maximum equivalent load contribution of rural domestic pollution to the water quality objectives of the Yellow River’s main streams and tributaries is merely 2.01%. Overall, rural per capita domestic sewage discharge in the basin is at a low level with obvious regional differences, mainly correlated with demographic, educational and climatic factors, and its impact on the basin’s water quality objectives is negligible.