Environmental efficiency of brazilian livestock farming: a regional greenhouse gas emissions approach

This article aims to establish a survey of CO2e (t GWP) emissions and carbon sequestration in Brazilian livestock. The study considers CO2, CH4, N2O as GHG, being presented in carbon equivalent (CO2eq) in the metric GWP (global warming potential). Based on data from Greenhouse Gas Emission and Removal Estimating System, an estimate of carbon removals in the soil due to agricultural practices was included in an experimental way. The assessment of GHG emissions from livestock over time and geographic space is essential so that mitigation measures are created, adopted and disseminated properly. Two indices were analyzed: Relative Herd Emissions Index (HREI) and Relative Carcass Emissions Index (CREI). From 1997 to 2019, Brazil increased its effective herd by 33.13%, gross GHG emissions by 31.62%, carbon sequestration by 91.20% and carcass weight by 146.45%. The zootechnical indices of beef cattle systems have improved over the years, reflecting the issues of environmental efficiency captured in the negative variations of the HREI and CREI indices. Net GHG emissions per animal (beef cattle) were reduced by -10.90%, while per kilogram of beef was produced by -51.81%.We demonstrate that the indicators used regionally can help as an alternative tool for the elaboration of national inventories and policy definitions aimed at the productive sector. For countries with a large territorial extension, different biomes and different livestock management, the identification of specific regional indexes bring precision to support scientific studies and governmental decisions that link regional development and the environment.