TY - JOUR
T1 - Nitrogen flows in global pork supply chains and potential improvement from feeding swill to pigs
AU - Uwizeye, Aimable
AU - Gerber, Pierre J.
AU - Opio, Carolyn I.
AU - Tempio, Giuseppe
AU - Mottet, Anne
AU - Makkar, Harinder P.S.
AU - Falcucci, Alessandra
AU - Steinfeld, Henning
AU - de Boer, Imke J.M.
PY - 2019/7
Y1 - 2019/7
N2 - The global pork sector contributes to food security and supports livelihoods for millions of households but also causes nitrogen (N) pollution. Here we assess N flows, losses, and N use indicators for global pork supply chains, from “cradle-to-primary-processing-gate” and for three production systems: the backyard, intermediate and industrial systems. Subsequently, we evaluate the effects of feeding swill to industrial pigs on N flows and land use. To produce 3.5 Tg N of pork globally, 14.7 Tg N are lost into the environment, of which 68% is lost to watercourses in the form of nitrates and organic N and the reminder emitted to the atmosphere as N-gas (e.g., NH 3 , NOx and N2O). We found that the efficiency of N use, hotspot and magnitude of N losses per unit of area depend chiefly on the region (agro-ecological and economic context), origin of feed, and manure management systems. Swill feeding increases N use efficiency and reduces N losses at the feed production stage. It achieves a saving of 31 Mt of soybeans and 20 Mt of grains on dry matter basis, equivalent to 16 M ha of land used. Its adoption would require innovative policies to preserve food safety and public health. Future research may explore the feasibility and requirements to adopt swill feeding at a country level and may investigate potential impacts on other sustainability objectives.
AB - The global pork sector contributes to food security and supports livelihoods for millions of households but also causes nitrogen (N) pollution. Here we assess N flows, losses, and N use indicators for global pork supply chains, from “cradle-to-primary-processing-gate” and for three production systems: the backyard, intermediate and industrial systems. Subsequently, we evaluate the effects of feeding swill to industrial pigs on N flows and land use. To produce 3.5 Tg N of pork globally, 14.7 Tg N are lost into the environment, of which 68% is lost to watercourses in the form of nitrates and organic N and the reminder emitted to the atmosphere as N-gas (e.g., NH 3 , NOx and N2O). We found that the efficiency of N use, hotspot and magnitude of N losses per unit of area depend chiefly on the region (agro-ecological and economic context), origin of feed, and manure management systems. Swill feeding increases N use efficiency and reduces N losses at the feed production stage. It achieves a saving of 31 Mt of soybeans and 20 Mt of grains on dry matter basis, equivalent to 16 M ha of land used. Its adoption would require innovative policies to preserve food safety and public health. Future research may explore the feasibility and requirements to adopt swill feeding at a country level and may investigate potential impacts on other sustainability objectives.
KW - Animal production
KW - Food wastes
KW - Life cycle
KW - Livestock
KW - Nitrogen use efficiency
U2 - 10.1016/j.resconrec.2019.03.032
DO - 10.1016/j.resconrec.2019.03.032
M3 - Article
AN - SCOPUS:85063665150
SN - 0921-3449
VL - 146
SP - 168
EP - 179
JO - Resources, Conservation and Recycling
JF - Resources, Conservation and Recycling
ER -