Carbon Stock and Chemical Fractionation of Organic Matter in Different Soil Management Systems in the Bahian Cerrado

• Published in: Communications in Soil Science and Plant Analysis 2024-12, Vol.55 (22), p.3562-3581
• Main Authors: da Silva Júnior, Jorge, Wendling, Beno, Rodrigues Torres, José Luiz, Nicchio, Bruno, Lemes, Ernane Miranda
• Format: Article
• Language: English
• Subjects: Agricultural conservation; Agricultural management; Bulk density; Carbon; Chemical fractionation; Conservation tillage; Conventional planting system; Fractionation; Fulvic acids; Humic acids; Management; Management systems; No-till cropping; no-tillage systems; Organic carbon; Organic matter; Organic soils; Parameters; Plant roots; Root development; Soil; Soil chemistry; Soil conservation; Soil density; Soil layers; Soil management; Soil organic matter; Soil quality; Soils; Tillage; Total organic carbon
• ISSN: 0010-3624; 1532-2416; 1532-4133
• DOI: 10.1080/00103624.2024.2402803

Determining total organic carbon and its stock and quantifying the chemical fractions of soil organic matter can be used as indicators of the quality of the soil management used in a cropping area. This study aimed to quantify soil organic matter's carbon stock and chemical fractions in different soil management systems used in the western Bahian Cerrado, Brazil, and compare them to a native Cerrado area. Ten microregions (Alto Horizonte, Anel da Soja, Bela Vista, Cascudeiro, Coaceral, Novo Paraná, Panambi, Placas, Roda Velha, Roda Velha de Baixo), three soil management systems [tillage system (TS), no-tillage systems (nTS), native Cerrado (NC)], and two soil layers (0-0.1 and 0.1-0.2 m) were studied. Soil bulk density (Sd), soil organic matter (SOM), total organic carbon (TOC), SOM quantification (qSOM), equivalent carbon stock (EqCs), humin (HF), humic acid (HAF) and fulvic acid (FAF) fractions from SOM were evaluated. The results indicated that Sd in all evaluated microregions was below the critical upper limit that would restrict plant root development. SOM, TOC, EqCs, and qSOM revealed increasing results following the TS, nTS, and NC order. The NC area presented the highest soil organic fraction contents (HF, HAF, and FAF). The microregions with better soil quality for all evaluated parameters were Coaceral and Cascudeiro; the lowest soil quality was observed in Alto Horizonte. The present study indicates that conservation agricultural management, such as the no-tillage system, improves the structure and composition of SOM parameters over time.