Soil Carbon Stocks and Greenhouse Gas Mitigation of Agriculture in the Brazilian Cerrado—A Review

Abstract

New agricultural practices and land-use intensification in the Cerrado biome have affected the soil carbon stocks. A major part of the native vegetation of the Brazilian Cerrado, a tropical savanna-like ecoregion, has been replaced by crops, which has caused changes in the soil carbon (C) stocks. To ensure the sustainability of this intensified agricultural production, actions have been taken to increase soil C stocks and mitigate greenhouse gas emissions. In the last two decades, new agricultural practices have been adopted in the Cerrado region, and their impact on C stocks needs to be better understood. This subject has been addressed in a systematic review of the existing data in the literature, consisting of 63 articles from the Scopus database. Our review showed that the replacement of Cerrado vegetation by crop species decreased the original soil C stocks (depth 0–30 cm) by 73%, with a peak loss of 61.14 Mg ha−1. However, when analyzing the 0–100 cm layer, 52.4% of the C stock data were higher under cultivated areas than in native Cerrado soils, with a peak gain of 93.6 Mg ha−1. The agricultural practices implemented in the Brazilian Cerrado make low-carbon agriculture in this biome possible.

Dynamics of Carbon and Soil Enzyme Activities under Arabica Coffee Intercropped with Brachiaria decumbens in the Brazilian Cerrado

“…In another study, in the state of Paraná in southern Brazil, where coffee was cultivated with rubber trees for 16 years, the C stock was 148.34 Mg ha −1 [ 1 ]. In the 0–60 cm layer of soils under no tillage with the presence of brachiaria (soybean/ Brachiaria ruziziensis /soybean and soybean/ Brachiaria ruziziensis ), De Carvalho et al [ 24 ] found higher soil C stocks than in native Cerrado, with gains of 5.2 and 4.4 Mg C ha −1 , respectively. This can be explained by the high capacity of pastures for shoot production, the particularly well-developed root system [ 28 ] and the positive management effect when plant residues are left on the soil surface.…”

“…The quantity and quality of plant residues left on the soil may promote a positive effect on soil C stocks [ 14 , 21 , 24 , 30 ]. In addition, several edaphoclimatic, topographical and land-use change factors can alter C stocks and mitigate nitrous oxide (N 2 O) emissions, depending on the management system [ 24 , 31 , 32 ]. The presence of brachiaria intercropped with coffee in this study should increase the soil C stocks in the long term, as stated by Rocha et al [ 2 ].…”

“…In general, the conversion of native areas to agricultural systems tends to decrease C stocks in the soil system, but agroforestry and organic production systems have great potential to increase C stocks in the soil [ 8 , 24 , 33 , 34 ].…”

“…The activity of arylsulfatase increased significantly in soil under brachiaria intercropped with coffee [ 15 ]. Other factors other than soil management also control SOM content and quality, e.g., soil texture, vegetation cover, climate and particularly the biochemical composition and quantity of plant residues [ 12 , 23 , 24 ]. The biochemical composition of plant residues affects the dynamics of decomposition and nutrient cycling [ 24 ], microbial biomass formation [ 9 ] and enzymatic activity [ 15 , 16 ].…”

Carbon Storage in Different Compartments in Eucalyptus Stands and Native Cerrado Vegetation

“…A Review on Soil Carbon Stocks and Greenhouse Gas Mitigation of Agriculture in the Brazilian Cerrado showed a range of studies conducted on the plot scale when native vegetation in Cerrado was converted to pasture or crops [ 19 ]. However, despite the expansion of eucalyptus culture in this Savanna environment [ 20 ], scarce information is available concerning the impact of Eucalyptus plantations on carbon stocks and GEE emission [ 10 , 21 , 22 , 23 , 24 , 25 , 26 ].…”