Fluxes, patterns and sources of phosphorus deposition in an urban–rural transition region in Southwest China

Understanding the patterns of atmospheric phosphorus (P) deposition is essential for assessing the global P biogeochemical cycle. Atmospheric P is an essential source of P in agricultural activities as well as eutrophication in waters; however, the information on P deposition is paid relatively less attention, especially in the anthropogenic influencing region. Therefore, this study chose a typical urban–rural transition as a representative case to monitor the dry and wet P depositions for 2 years. The results showed that the fluxes of atmospheric total P deposition ranged from 0.50 to 1.06 kg P hminline-formula⁻² yrinline-formula⁻¹, and the primary form was atmospheric dry P deposition (76.1 %, 0.76–0.84 kg P hminline-formula⁻² yrinline-formula⁻¹). Moreover, it was found that the monthly variations of P deposition were strongly correlated with meteorological factors, including precipitation, temperature and relative humidity. However, the fluxes of dry P deposition and total P deposition were more affected by land use, which increased with the agro-facility, town and paddy field areas but decreased with the forest and country road areas. These findings suggested that dry P deposition was the primary form of total P deposition, and P deposition could be affected both by meteorological factors and land-use types. Thus, proper management of land use may help mitigate the pollution caused by P deposition.