Greenhouse gas balance and carbon footprint of beef cattle in three contrasting pasture-management systems in Brazil
Author: Eduardo Barretto de Figueiredo , Susantha Jayasundara, Ricardo de Oliveira Bordonal , Telma Teresinha Berchielli, Ricardo Andrade Reis, Claudia Wagner-Riddle, Newton La Scala Jr.
Keywords: Climate change, Land-use change, Livestock emissions, Grazing management, Integrated systems, Meat production
Integrated Systems (IS) have been identified as an efficient land-management strategy for restoring degraded areas worldwide, increasing crops and beef yields and providing technical potential for carbon (C) sequestration in soil and trees as an option for offsetting CH4 and N2O emissions from cattle production. The aim of our study is to estimate the greenhouse gas (GHG) balance and the C footprint of beef cattle (fattening cycle) in three contrasting production scenarios on the Brachiaria pasture in Brazild1) degraded pasture (DP), 2) managed pasture (MP), and 3) the crop-livestock-forest integrated system (CLFIS)dpresenting new alternatives of land use as a GHG mitigation strategy. Area-scaled total GHG emissions were highest in MP (84,541 kg CO2eq ha1 ), followed by CLFIS (64,519 kg CO2eq ha1 ) and DP (8004 kg CO2eq ha1 ) over a 10-yr period. Our results note that the highest C footprint of beef cattle was in the DP, 18.5 kg CO2eq per kg LW (live weight), followed by 12.6 kg CO2eq per kg LW in the CLFIS and 9.4 kg CO2eq per kg LW in the MP, without taking into account the technical potential for C sequestration in MP (soil C) and CLFIS (soil and Eucalyptus C). Considering the potential for soil C sequestration in the MP and CLFIS, the C footprint of beef cattle could be reduced to 7.6 and 28.1 kg CO2eq per kg LW in the MP and CLFIS, respectively. The conversion of the degraded pasture to a well-managed pasture and the introduction of CLFIS can reduce their associated GHG emissions in terms of kg CO2eq emitted per kg of cattle LW produced, increasing the production of meat, grains and timber. This reduction is primarily due to pasture improvement and increases in cattle yields and the provision of technical potential for C sinks in soil and biomass to offset cattle-related emissions.