Feeding Efficiency Gains Can Increase the Greenhouse Gas Mitigation Potential of the Tanzanian Dairy Sector

Abstract

We use an attributional life cycle assessment (LCA) and simulation modelling to assess the effect of improved feeding practices and increased yields of feed crops on milk productivity and GHG emissions from the dairy sector of Tanzania’s southern highlands region. We calculated direct non-CO2 emissions from dairy production and the CO2 emissions resulting from the demand for croplands and grasslands using a land footprint indicator. Baseline GHG emissions intensities ranged between 19.8 - 27.8 and 5.8 - 5.9 kg CO2eq kg-1 fat and protein corrected milk for the Traditional (local cattle) and Modern (improved cattle) sectors. Land use change contributed 45.8 - 65.8% of the total carbon footprint of dairy. Better feeding increased milk yields by up to 60.1% and reduced emissions intensities by up to 52.4 and 38.0% for the Traditional and Modern sectors, respectively. Avoided land use change was the predominant cause of reductions in GHG emissions under all the scenarios. Reducing yield gaps of concentrate feeds lowered emission further by 11.4 – 34.9% despite increasing N2O and CO2 emissions from soils management and input use. This study demonstrates that feeding intensification has potential to increase LUC emissions from dairy production, but that fertilizer-dependent yield gains can offset this increase in emissions, through avoided emissions from land use change.

The carbon footprint of livestock farms under conventional management and silvopastoral systems in Jalisco, Chiapas, and Campeche (Mexico)

“…Livestock activity contributes between 12 and 14.5% of anthropogenic greenhouse gas (GHG) emissions, with milk and meat production responsible for 3-4% (Velarde-Guillén et al, 2022) and 11-12%, respectively (Grain, 2017). Methane (CH 4 ) is the major contributor to these emissions, but with a wide range, from 34 to 86% (Gerber et al, 2013;Rice et al, 2017;Mazzetto et al, 2020;González-Quintero et al, 2021;Hawkins et al, 2021), with some researchers finding rates of more than 70%. Mexico is the 12th biggest emitter of CO 2 in the world (International Energy Agency [IEA], 2020) and accounts for 1% of global GHG emissions (He et al, 2021).…”