BALANÇO DE CO2 NA BIOMASSA E NOS SOLOS DE ÁREAS AGRÍCOLAS NO BRASIL EM UM CENÁRIO BAIXO CARBONO

Abstract

It is estimated that the concentration of greenhouse gases in the atmosphere has already increased 40% since 1750. Changes in carbon stocks in the biomass and soils constitute the second largest source of carbon to the atmosphere within this scenario, and the agricultural sector is considered key to achieving a low carbon development. This segment proves to be important both for the representativity of its emissions and its importance in the economy as for the mitigation opportunities it offers. Thus, this study aimed to estimate carbon emissions and sequestration in the biomass and soils in areas with agricultural land use over the period 2011-2022, through spatially explicit modeling, based on the land-use projections estimated for a Low Carbon scenario. The results indicated sequestration of 1424 Mt of CO2e for the period (1134 Mt of CO2e by biomass and 290 Mt of CO2e by soils), and an annual average of 118 Mt de CO2e. This annual value corresponds to 80% of the goals of reducing greenhouse gases emissions proposed for the agricultural sector by the government in the National Climate Change Plan to 2020. To achieve such results, pastures stood out as a key category in pursuit of a low-carbon agriculture, since the expansion of cropland areas and particularly of planted forests over grasslands showed great potential for carbon sequestration, 716 Mt of CO2e, as well as the recovery of degraded grasslands, 234 Mt of CO2e. Such carbon sequestration magnitude was only possible because the analyzes were based on a scenario which involved the combination of various mitigation practices combined with absence of deforestation. The produced model, as well as the results of this study, may be used as tools and considered trends for guiding actions towards a low-carbon agriculture.