Staff Publications

Staff Publications

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    'Staff publications' is the digital repository of Wageningen University & Research

    'Staff publications' contains references to publications authored by Wageningen University staff from 1976 onward.

    Publications authored by the staff of the Research Institutes are available from 1995 onwards.

    Full text documents are added when available. The database is updated daily and currently holds about 240,000 items, of which 72,000 in open access.

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The value of manure - Manure as co-product in life cycle assessment
Leip, Adrian ; Ledgard, Stewart ; Uwizeye, Aimable ; Palhares, Julio C.P. ; Aller, M.F. ; Amon, Barbara ; Binder, Michael ; Cordovil, Claudia M.D.S. ; Camillis, Camillo De; Dong, Hongming ; Fusi, Alessandra ; Helin, Janne ; Hörtenhuber, Stefan ; Hristov, Alexander N. ; Koelsch, Richard ; Liu, Chunjiang ; Masso, Cargele ; Nkongolo, Nsalambi V. ; Patra, Amlan K. ; Redding, Matthew R. ; Rufino, Mariana C. ; Sakrabani, Ruben ; Thoma, Greg ; Vertès, Françoise ; Wang, Ying - \ 2019
Journal of Environmental Management 241 (2019). - ISSN 0301-4797 - p. 293 - 304.
Livestock production is important for food security, nutrition, and landscape maintenance, but it is associated with several environmental impacts. To assess the risk and benefits arising from livestock production, transparent and robust indicators are required, such as those offered by life cycle assessment. A central question in such approaches is how environmental burden is allocated to livestock products and to manure that is re-used for agricultural production. To incentivize sustainable use of manure, it should be considered as a co-product as long as it is not disposed of, or wasted, or applied in excess of crop nutrient needs, in which case it should be treated as a waste. This paper proposes a theoretical approach to define nutrient requirements based on nutrient response curves to economic and physical optima and a pragmatic approach based on crop nutrient yield adjusted for nutrient losses to atmosphere and water. Allocation of environmental burden to manure and other livestock products is then based on the nutrient value from manure for crop production using the price of fertilizer nutrients. We illustrate and discuss the proposed method with two case studies.
Global environmental costs of China's thirst for milk
Bai, Zhaohai ; Lee, Michael R.F. ; Ma, Lin ; Ledgard, Stewart ; Velthof, Gerard L. ; Ma, Wenqi ; Guo, Mengchu ; Zhao, Zhanqing ; Wei, Sha ; Li, Shengli ; Liu, Xia ; Havlík, Petr ; Luo, Jiafa ; Hu, Chunsheng ; Zhang, Fusuo - \ 2018
Global Change Biology 24 (2018)5. - ISSN 1354-1013 - p. 2198 - 2211.
Cattle feed - Greenhouse gas - Land use, nitrogen losses - Milk trade - Shared socio-economic pathways scenarios
China has an ever-increasing thirst for milk, with a predicted 3.2-fold increase in demand by 2050 compared to the production level in 2010. What are the environmental implications of meeting this demand, and what is the preferred pathway? We addressed these questions by using a nexus approach, to examine the interdependencies of increasing milk consumption in China by 2050 and its global impacts, under different scenarios of domestic milk production and importation. Meeting China's milk demand in a business as usual scenario will increase global dairy-related (China and the leading milk exporting regions) greenhouse gas (GHG) emissions by 35% (from 565 to 764 Tg CO 2eq ) and land use for dairy feed production by 32% (from 84 to 111 million ha) compared to 2010, while reactive nitrogen losses from the dairy sector will increase by 48% (from 3.6 to 5.4 Tg nitrogen). Producing all additional milk in China with current technology will greatly increase animal feed import; from 1.9 to 8.5 Tg for concentrates and from 1.0 to 6.2 Tg for forage (alfalfa). In addition, it will increase domestic dairy related GHG emissions by 2.2 times compared to 2010 levels. Importing the extra milk will transfer the environmental burden from China to milk exporting countries; current dairy exporting countries may be unable to produce all additional milk due to physical limitations or environmental preferences/legislation. For example, the farmland area for cattle-feed production in New Zealand would have to increase by more than 57% (1.3 million ha) and that in Europe by more than 39% (15 million ha), while GHG emissions and nitrogen losses would increase roughly proportionally with the increase of farmland in both regions. We propose that a more sustainable dairy future will rely on high milk demanding regions (such as China) improving their domestic milk and feed production efficiencies up to the level of leading milk producing countries. This will decrease the global dairy related GHG emissions and land use by 12% (90 Tg CO 2eq reduction) and 30% (34 million ha land reduction) compared to the business as usual scenario, respectively. However, this still represents an increase in total GHG emissions of 19% whereas land use will decrease by 8% when compared with 2010 levels, respectively.
Strategies to mitigate nitrous oxide emissions from herbivore production systems
Schils, R.L.M. ; Eriksen, J. ; Ledgard, S. ; Vellinga, Th.V. ; Kuikman, P.J. ; Luo, J. ; Petersen, S.O. ; Velthof, G.L. - \ 2013
Animal 7 (2013)Suppl. 1. - ISSN 1751-7311 - p. 29 - 40.
greenhouse-gas emissions - ruminant livestock systems - hippuric-acid content - cattle slurry - new-zealand - n2o emissions - nitrifier denitrification - nitrification inhibitor - climate-change - dinitrogen emissions
Herbivores are a significant source of nitrous oxide (N2O) emissions. They account for a large share of manure-related N2O emissions, as well as soil-related N2O emissions through the use of grazing land, and land for feed and forage production. It is widely acknowledged that mitigation measures are necessary to avoid an increase in N2O emissions while meeting the growing global food demand. The production and emissions of N2O are closely linked to the efficiency of nitrogen (N) transfer between the major components of a livestock system, that is, animal, manure, soil and crop. Therefore, mitigation options in this paper have been structured along these N pathways. Mitigation technologies involving diet-based intervention include lowering the CP content or increasing the condensed tannin content of the diet. Animal-related mitigation options also include breeding for improved N conversion and high animal productivity. The main soil-based mitigation measures include efficient use of fertilizer and manure, including the use of nitrification inhibitors. In pasture-based systems with animal housing facilities, reducing grazing time is an effective option to reduce N2O losses. Crop-based options comprise breeding efforts for increased N-use efficiency and the use of pastures with N2-fixing clover. It is important to recognize that all N2O mitigation options affect the N and carbon cycles of livestock systems. Therefore, care should be taken that reductions in N2O emissions are not offset by unwanted increases in ammonia, methane or carbon dioxide emissions. Despite the abundant availability of mitigation options, implementation in practice is still lagging. Actual implementation will only follow after increased awareness among farmers and greenhouse gases targeted policies. So far, reductions in N2O emissions that have been achieved are mostly a positive side effect of other N-targeted policies.
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