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 and 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 feed crops lowered emissions further by 11.4–34.9% despite increasing N2O and CO2 emissions from soils management and input use. This study demonstrates that feed 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.

Technical performance and carbon footprint of commercial dairy farms in South West Uganda

“…In Tanzania GHG emissions intensities ranged between 5.8-5.9 kg CO2-eq/kg fat and protein corrected milk for modern (improved cattle) sectors (Hawkins et al, 2021). Average GHG emission intensity in This finding highlights the importance of including LUC in future LCA studies in Uganda.…”

“…GHG emissions related to land use and land use change (LULUC) were not included in this LCA, because of its complexity (e.g., De Rosa, 2018; Hawkins et al, 2021).…”

“…Van Middelaar et al, 2013). A better alternative is to close the yield gap of maize by increasing N fertilizer use, which can reduce emission intensities due to avoiding emissions from conversion of grazing land (Brandt et al, 2019;Hawkins et al, 2021).…”

Improved animal genetics deliver low emissions development in East Africa’s dairy sector

“…The land footprint is calculated with feed biomass, land use, yield and feed use efficiencies of each feedstuff 38 . Changes in herd size for each scenario results in changes to the demand for cropland and grasslands and land use transitions which are used to calculate CO2 emissions in the LCA (see 'CO2 emissions from land use change').…”

Perspectives on Reducing the National Milk Deficit and Accelerating the Transition to a Sustainable Dairy Value Chain in Zimbabwe

“…If herd sizes grow to meet the demand and reduce the milk deficit, the total GHG emissions and water use are also likely to increase. To counteract this, herd growth needs to co-occur with productivity increases to reduce GHG emissions and water use (e.g., Douxchamps et al, 2021;Hawkins et al, 2021) per liter of milk. Increased productivity has to go hand-in-hand with increased land and water productivity (more animal nutrition per area of land and liter of water) and feed efficiency (more animal product per unit of feed), to avoid clearing of more land to produce feed, and enhance milk production per unit animal, water and land, respectively.…”