Net Anthropogenic Phosphorus Accumulation in the Beijing Metropolitan Region

Abstract

Phosphorus (P) is one of main pollution elements of eutrophication. P emissions from different pathways and sources are a key issue in the protection of water quality and sustainable watershed management practices. We have estimated net anthropogenic P accumulation (NAPA), as an index of P pollution potential in the Beijing metropolitan region, China. The NAPA estimation is based on an inventory of P fertilizer use, consumption of human food and animal feed, non-food P, and riverine P net flux. The overall average NAPA for 1991, 1997, 2003, and 2007 are 777, 943, 1218, and 1084 kg P km -2 y -1 , about two times that reported in developed countries. The Urban unit has the largest NAPA (5526 kg P km -2 y -1 ), whereas Mentougou P was negative, outputting 34 kg P km -2 y -1 . P input of fertilizer is the largest source of NAPA, accounting for 40.7% (455 kg P km -2 y -1 ) of the total P input, followed by non-food P and P in human food and animal feed. NAPA is closely related to land use, on average 5433 kg P km -2 y -1 in densely populated developed land, 503 kg P km -2 y -1 in agricultural land and 84 kg P km -2 y -1 in forest land. Human population density is the best single predictor of NAPA. Our results provide a basis for understanding the potential impact of anthropogenic P inputs on environmental problems, such as nation-wide water quality degradation under the current rapid urban expansion in modern China.

Factors controlling phosphorus export from agricultural/forest and residential systems to rivers in eastern China, 1980–2011

“…In terms of NAPI R , a major sink for P is removal of domestic solid waste and sewage from residential areas (Russell et al, 2008;Han et al, 2011bHan et al, , 2013Chen et al, 2015a). For the upper Jiaojiang watershed, there has been partial collection and transport of domestic wastes to landfills, incinerators, biogas digesters, septic-tanks or wastewater treatment plants (Table 1).…”

“…Calculation of net anthropogenic phosphorus input (NAPI) is a P budgeting approach that sums annual P contributions from atmospheric deposition, fertilizer application, non-food input (i.e., detergent P), seed input, and net import/export in animal feed and human food supplies (Han et al, 2013). The NAPI approach has been successfully applied to many watersheds across Asia (Han et al, 2011b(Han et al, , 2013Chen et al, 2015a), the Americas (David and Gentry, 2000;Borbor-Cordova et al, 2006;Han et al, 2011a;Russell et al, 2008;Sobota et al, 2011), and Europe (Hong et al, 2012). It is a simple yet powerful approach to evaluate net P inputs from anthropogenic sources to terrestrial ecosystems, as well as an effective tool to explain among-watershed or among-year variations in riverine P exports.…”

Influence of legacy phosphorus, land use, and climate change on anthropogenic phosphorus inputs and riverine export dynamics

“…Phosphorus sorption in bottom sediments of ditches, streams and rivers may be another important P sink, especially when water velocity is slow and the sediment P sorption capacity is not saturated (David and Gentry 2000;Sharpley et al 2013;Jarvie et al 2013). Furthermore, due to the unavailability of public records we could not account for the amount of municipal waste and sewage sludge that was removed from residential areas and transported to landfills, incinerators or farmlands, which is a potential fate for a portion of the NAPI (Russell et al 2008;Han et al 2011b). …”

“…To examine spatio-temporal variation for the anthropogenic P budget, annual net anthropogenic P inputs (NAPI, kg P ha -1 year -1 ) in each of the six catchments for the 1980-2010 study period were estimated as the sum of four major components: atmospheric P deposition (AD), commercial fertilizer P application (CF), net food, feed and seed P input (NFFSI), and detergent P or non-food P input (NFI) (Russell et al 2008;Han et al 2011bHan et al , 2013. Wastewater discharge was not considered explicitly in the NAPI analysis, since P in wastewater originates from food, feed and detergents (Hong et al 2012).…”

Deteriorated Water Quality of Agricultural Catchments in South China by Net Anthropogenic Phosphorus Inputs

“…This result differs from those of previous studies. Other research has shown that population density was the best predictor for singly forecasting NAPI [4,8] in an urbanized region and higher proportions of developed land. Agricultural catchments with higher livestock density require imports of P in feed from outside the region boundaries to meet the high demands that cannot be met by local P reservoirs.…”