Impact of Agricultural Non-Point Source Pollution on River Water Quality: Evidence From China

Identifying the effect of agricultural non-point source pollutants on water quality is very important for pollution management. This study used NH 3 N as an indicator to empirically influence fertilizer application river based panel data 46 prefecture-level cities and 18 state-controlled monitoring points through which main streams Yangtze River Yellow flow from 2004 2019. It found that: (1) An increase in amount will exacerbate pollution, worsening upper watershed precipitation lead transboundary lower watershed. (2) The intensity had a threshold pollution. When former exceeded value 11.496 tons, latter 7.991 ton/km 2 , positive rivers was further enhanced. (3) applied long-term lagged effect, number lags increased, accumulative negative gradually rose. Based findings empirical study, it proposed that inter-basin inter-regional synergy should be formed prevention control overall top-level design subsidies environmental policies areas along basin considered.