Refinar búsqueda
Resultados 1-10 de 15
Model-based analysis of phosphorus flows in the food chain at county level in China and options for reducing the losses towards green development
2021
Zhou, Jichen | Jiao, Xiaoqiang | Ma, Lin | de Vries, Wim | Zhang, Fusuo | Shen, Jianbo
Insight in the phosphorus (P) flows and P balances in the food chain is largely unknown at county scale in China, being the most appropriate spatial unit for nutrient management advice. Here, we examined changes in P flows in the food chain in a typical agricultural county (Quzhou) during 1980–2017, using substance flow analyses. Our results show that external P inputs to the county by feed import and fertilizer were 7 times greater in 2017 than in 1980, resulting in a 7-fold increase in P losses to the environment in the last 3 decades, with the biggest source being animal production. Phosphorus use efficiency decreased from 51% to 30% in crop production (PUEc) and from 32% to 11% in the whole food chain (PUEf), but increased from 4% to 7% in animal production (PUEa). A strong reduction in P inputs and thus increase in PUE can be achieved by balanced P fertilization, which is appropriate for Quzhou considering a current average adequate soil P status. Fertilizer P use can be reduced from 7276 tons yr⁻¹ to 1765 tons yr⁻¹ to equal P removal by crops. This change would increase P use efficiency for crops from 30% to 86% but it has a negligible effect on P losses to landfills and water bodies. Increasing the recycling of manure P from the current 43%–95% would reduce fertilizer P use by 17% and reduce P losses by 47%. A combination of reduced fertilizer P use and increased recycling of manure P would save fertilizer P by 93%, reduce P accumulation by 100% and P loss by 49%. The results indicate that increasing manure-recycling and decreasing fertilizer-application are key to achieving sustainable P use in the food chain, which can be achieved through coupling crop-livestock systems and crop-based nutrient management.
Mostrar más [+] Menos [-]Environmental hazards of nitrogen loading in wetland rice fields
1998
Ghosh, B.C. | Ravi Bhat (Agricultural and Food Engineering Department, Indian Institute of Technology, Kharagpur 721 302 (India))
Air-soil exchange of semi-volatile organic compounds (SOCs) in the UK
1998
Cousins, I.T. | Jones, K.C. (Environmental Science Department, Institute of Environmental and Natural Sciences, Lancaster University, Lancaster LA1 4YQ (United Kingdom))
The European critical levels for ozone: improving their usage
1999
Grunhage, L. | Jager, H.J. | Haenel, H.D. | Lopmeier, F.J. | Hanewald, K. (Institute for Plant Ecology, University of Giessen, Heinrich-Buff-Ring 38, D-35392 Giessen, Germany)
Polychlorinated biphenyls in a rural watershed in the southern prairie region of Canada
1998
Rawn, D.F.K. | Halldorson, T.H.J. | Lawson, B.D. | Muir, D.C.G. (Department of Soil Science, University of Manitoba, Winnipeg, Manitoba, R3T 2N2 (Canada))
Soil nitrous oxide and nitric oxide emissions as indicators of elevated atmospheric N deposition rates in seminatural ecosystems
1998
Skiba, U. | Sheppard, L. | Pitcairn, C.E.R. | Leith, I. | Crossley, A. | Dijk, S. van | Kennedy, V.H. | Fowler, D. (Institute of Terrestrial Ecology (ITE), Bush Estate, Penicuik EH26 0QB (United Kingdom))
Impacts and fate of experimentally enhanced nitrogen deposition on a British lowland heath
1998
Power, S.A. | Ashmore, M.R. | Cousins, D.A. (Imperial College of Science, Technology and Medicine, Silwood Park, Ascot, Berkshire SL5 7PY (United Kingdom))
[How to reduce agricultural nitrogen losses?]
1993
Pedersen, C.Aa.
The role of nitrogen in crop production and losses of nitrate by leaching from agricultural soil
1994
Johnston, A.E. (IACR, Rothamsted, Harpenden (AL5 2JQ,UK))
The large-scale flux of nutrients from land to water and the eutrophication of lakes and marine waters
1994
Forsberg, C. (Institute of Limnology, Uppsala University, Norbyvag. 20, 752 36, Uppsala (Sweden))
