title: Estimation of nitrogen and phosphorus flows in livestock production in Dianchi Lake basin, China.
abstract: We assessed the nitrogen (N) and phosphorus (P) flows in intensified livestock production systems by investigating nutrient budgets and cycling in the basin of Dianchi Lake, one of the most eutrophic lakes in China. We conducted field surveys based on feed samplings and interviews of livestock farmers. The N and P in local and external feeds, animal body retentions, animal products and excretions were calculated at the individual level for dairy cattle, fattening pigs, breeding sows, broilers and laying hens. The N and P flows in the total livestock production system in the area were estimated by multiplying the individual N and P budgets by the number of animals. For the dairy and fattening pig productions, N and P supplied from local crops or by-products accounted for large parts of the inputs. For the other livestock categories, most of the N and P inputs depended on external resources. The N and P outputs through animal manure into the cropland were 287 and 66 kg/ha/year, respectively, which were higher than the N and P inputs into the livestock production systems from the cropland. The N and P loads from manure should be reduced for the establishment of sustainable agricultural production systems.
authors.affiliation: Graduate School of Agriculture, Kyoto University, Kyoto, Japan.
authors.forename: Hiroki
authors.identifier: http://orcid.org/0000-0002-6241-313X
authors.initials: H
authors.lastname: Anzai
authors.affiliation: Graduate School of Agriculture, Kyoto University, Kyoto, Japan.
authors.forename: Lin
authors.initials: L
authors.lastname: Wang
authors.affiliation: Graduate School of Agriculture, Kyoto University, Kyoto, Japan.
authors.forename: Kazato
authors.initials: K
authors.lastname: Oishi
authors.affiliation: Biotechnology Research Center, Kunming University of Science and Technology, Kunming, China.
authors.forename: Chagan
authors.initials: C
authors.lastname: Irbis
authors.affiliation: Biotechnology Research Center, Kunming University of Science and Technology, Kunming, China.
authors.forename: Kunzhi
authors.initials: K
authors.lastname: Li
authors.affiliation: Graduate School of Agriculture, Kyoto University, Kyoto, Japan.
authors.forename: Hajime
authors.initials: H
authors.lastname: Kumagai
authors.affiliation: Graduate School of Agriculture, Kyoto University, Kyoto, Japan.
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Inamura
authors.affiliation: Graduate School of Agriculture, Kyoto University, Kyoto, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Hirooka
mesh_terms: D000383:Agriculture; D000821:Animal Feed; D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D002417:Cattle; D002645:Chickens; D002681:China; D005260:Female; D005618:Fresh Water / Q000737:chemistry; D060106:Lakes / Q000032:analysis; D058751:Livestock / Q000378:metabolism*; D008297:Male; D009584:Nitrogen / Q000032:analysis / Q000378:metabolism*; D010758:Phosphorus / Q000032:analysis / Q000378:metabolism*; D013552:Swine; D014873:Water Pollutants / Q000032:analysis; D014876:Water Pollution / Q000032:analysis / Q000517:prevention & control
chemical_list: D014873:Water Pollutants; D010758:Phosphorus; D009584:Nitrogen
keywords: China; livestock production system; nitrogen; nutrient flow; phosphorus