Estimativa de emissão de gases de efeito estufa e captura de carbono em fazenda de pecuária no Centro-Oeste do Brasil

Abstract

According to the Low Carbon Agriculture Plan (ABC+), among the various strategies for recovering degraded areas, the introduction of integrated systems stands out as a highly profitable and sustainable alternative. The implementation of these systems promotes significant improvements in productivity, soil quality, and ecosystem balance, generating socio-economic and environmental benefits. In this context, the present study quantified greenhouse gas (GHG) emissions through an inventory prepared according to the 2006 IPCC guidelines, in an area located in Serranópolis, Goiás. Four distinct scenarios were analyzed: Livestock-Forest Integration (ILF), Managed Pasture 1 (MP 1), Managed Pasture 2 (MP 2), and Eucalyptus Monoculture (EM). All systems originated from the conversion of a PM 1 area. To understand the dynamics of carbon stock, soil organic carbon, and the humification index of organic matter in each scenario, chemical and physical analyses of soil elements were performed using advanced photonic technologies such as Laser-Induced Breakdown Spectroscopy (LIBS) and Laser-Induced Fluorescence Spectroscopy (LIFS). The carbon footprint results indicated the following values: 14.7 kg CO₂eq kg⁻¹ of live weight gain (LWG) for the ILF system, 10.9 kg CO₂eq kg⁻¹ LWG for MP 1, and 17 kg CO₂eq kg⁻¹ LWG for MP 2. When considering the carbon balance, integrating all emission sources and carbon sequestration by aerial biomass in the IPF and EM systems, a negative balance of 15,267.33 tCO₂eq year⁻¹ was observed. Estimates suggest that carbon sequestration in the ILF system reached 5,673,439.2 kg CO₂eq year⁻¹, sufficient not only to offset all GHG emissions from this system but also to generate a potential credit of 4,547,484.03 kg CO₂eq year⁻¹. Additionally, the conversion from MP 1 to ILF indicated a soil carbon accumulation of 2.45 t C ha⁻¹ year⁻¹, equivalent to the absorption of 8.98 t CO₂ ha⁻¹ year⁻¹ from the atmosphere. For the EM system, considering the same baseline scenario and a period of 10 years after eucalyptus planting, a soil carbon accumulation of 0.24 t C ha⁻¹ year⁻¹ was estimated, corresponding to the absorption of 0.88 t CO₂ ha⁻¹ year⁻¹ from the atmosphere. These results highlight the relevance of integrated systems in the context of sustainable agriculture aligned with global climate goals.