Carbon Stocks in Brazilian Latosols (Oxisols) from Different Morphoclimatic Regions and Management Systems

• Published in: Communications in soil science and plant analysis 2005-01, Vol.35 (15-16), p.2125-2136
• Main Authors: Andrade, F. V., Schaefer, C. E. G. R., Correa, M. L. T., Mendonça, E. S.
• Format: Article
• Language: English
• Subjects: Agronomy. Soil science and plant productions; Biological and medical sciences; Carbon sequestration; Chemical, physicochemical, biochemical and biological properties; Fundamental and applied biological sciences. Psychology; Organic matter; Organic matter stability; Physics, chemistry, biochemistry and biology of agricultural and forest soils; Soil organic matter; Soil science; Tropical land use; Tropical soils
• ISSN: 0010-3624; 1532-2416
• DOI: 10.1081/LCSS-200028959

Soil organic matter (SOM) is the greatest carbon reservoir in the terrestrial ecosystem, reaching approximately 1.500 × 10 9 t of carbon (C). The knowledge of the size and dynamics of this compartment is essential for carbon stock evaluation, leading to a national inventory of carbon fluxes, as well as the modeling of tropical carbon cycles. Latosols (oxisols) cover approximately 40% of the Brazilian territory, being important with regard to SOM accumulation. This process can occur both at the surface and within minute aggregates at greater depths. The mean C stock values were calculated for Brazilian Latosols (Red Latosol-RL, Yellow Latosol-YL, Red Yellow Latosol-RYL, and Humic Latosols-HL); in addition, we evaluated the effects of climate, vegetation, and land use on C stocks. A database was used of organic carbon contents of A and B horizon of Latosols from different morphoclimatic regions (humid tropical northern Brazil, semi-arid, northeast, coastal Atlantic southeast, dry topical central, and subtropical southern) compiled from the extensive RADAMBRASIL and EMBRAPA soil surveys. The mean C stock values of Brazilian Latosols are: 6 and 13 kg m −2 for YL; 7.5 and 11 kg m −2 for RL; 6.8 and 8.8 kg m −2 for RYL; and 30.16 and 15.78 kg m −2 for HL, for A and B horizons, respectively. Carbon stock values were markedly influenced by regional climate, type of vegetation, and land use. The usually neglected pool of organic carbon in B horizons of deeply weathered Latosols accounts for between 42-76% of the total C stocks.