title: Environmental impacts of innovative dairy farming systems aiming at improved internal nutrient cycling: A multi-scale assessment.
abstract: Several dairy farms in the Netherlands aim at reducing environmental impacts by improving the internal nutrient cycle (INC) on their farm by optimizing the use of available on-farm resources. This study evaluates the environmental performance of selected INC farms in the Northern Friesian Woodlands in comparison to regular benchmark farms using a Life Cycle Assessment. Regular farms were selected on the basis of comparability in terms of milk production per farm and per hectare, soil type and drainage conditions. In addition, the environmental impacts of INC farming at landscape level were evaluated with the integrated modelling system INITIATOR, using spatially explicit input data on animal numbers, land use, agricultural management, meteorology and soil, assuming that all farms practised the principle of INC farming. Impact categories used at both farm and landscape levels were global warming potential, acidification potential and eutrophication potential. Additional farm level indicators were land occupation and non-renewable energy use, and furthermore all farm level indicators were also expressed per kg fat and protein corrected milk. Results showed that both on-farm and off-farm non-renewable energy use was significantly lower at INC farms as compared with regular farms. Although nearly all other environmental impacts were numerically lower, both on-farm and off-farm, differences were not statistically significant. Nitrogen losses to air and water decreased by on average 5 to 10% when INC farming would be implemented for the whole region. The impact of INC farming on the global warming potential and eutrophication potential was, however, almost negligible (<2%) at regional level. This was due to a negligible impact on the methane emissions and on the surplus and thereby on the soil accumulation and losses of phosphorus to water at INC farms, illustrating the focus of these farms on closing the nitrogen cycle.
authors.affiliation: Alterra, Wageningen University and Research Centre, PO Box 47, 6700 AA Wageningen, The Netherlands; Environmental Systems Analysis Group, Wageningen University, PO Box 47, 6700 AA Wageningen, The Netherlands. Electronic address: wim.devries@wur.nl.
authors.forename: W
authors.initials: W
authors.lastname: de Vries
authors.affiliation: Alterra, Wageningen University and Research Centre, PO Box 47, 6700 AA Wageningen, The Netherlands.
authors.forename: J
authors.initials: J
authors.lastname: Kros
authors.affiliation: Animal Production Systems Group, Wageningen University, Wageningen, The Netherlands; Agricultural Economics Research Institute, Wageningen University and Research Centre, PO Box 29703, 2502 LS, The Hague, The Netherlands.
authors.forename: M A
authors.initials: MA
authors.lastname: Dolman
authors.affiliation: Wageningen Livestock research, Wageningen University and Research Centre, PO Box 65, 8200 AB Lelystad, The Netherlands.
authors.forename: Th V
authors.initials: TV
authors.lastname: Vellinga
authors.affiliation: Wageningen Livestock research, Wageningen University and Research Centre, PO Box 65, 8200 AB Lelystad, The Netherlands.
authors.forename: H C
authors.initials: HC
authors.lastname: de Boer
authors.affiliation: Alterra, Wageningen University and Research Centre, PO Box 47, 6700 AA Wageningen, The Netherlands.
authors.forename: A L
authors.initials: AL
authors.lastname: Gerritsen
authors.affiliation: Soil Geography and Landscape Group, Wageningen University, PO Box 47, 6700 AA Wageningen, The Netherlands.
authors.forename: M P W
authors.initials: MPW
authors.lastname: Sonneveld
authors.affiliation: Wageningen University, The Netherlands. Electronic address: Johan.bouma@planet.nl.
authors.forename: J
authors.initials: J
authors.lastname: Bouma
mesh_terms: D000818:Animals; D003612:Dairying / Q000379:methods*; D004777:Environment; D005068:Eutrophication; D009426:Netherlands; D009584:Nitrogen; D058458:Nitrogen Cycle; D010758:Phosphorus; D014876:Water Pollution / Q000517:prevention & control*
chemical_list: D010758:Phosphorus; D009584:Nitrogen
keywords: Acidification potential; Dairy farms; Eutrophication potential; Global warming potential; Landscape model; Life cycle assessment; Nutrient cycle