Carbon stocks and pools in relation to the texture of kaolinitic soils from the brazilian east coast
Extremely kaolinitic soils of Tertiary age elevations on the Brazilian east coast present a wide range of texture, which is recognized as one of the main factors controlling the soil organic matter contents. This study aimed to investigate the organic C storage of different compartments of kaoliniti...
| Autores: | , , , , , |
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| Tipo de recurso: | artículo |
| Estado: | Versión publicada |
| Fecha de publicación: | 2018 |
| País: | Brasil |
| Institución: | Universidade Federal de Lavras (UFLA) |
| Repositorio: | Repositório Institucional da UFLA |
| Idioma: | inglés |
| OAI Identifier: | oai:repositorio.ufla.br:1/33033 |
| Acceso en línea: | https://repositorio.ufla.br/handle/1/33033 |
| Access Level: | acceso abierto |
| Palabra clave: | Dissolved organic C Aggregate size distribution Coastal tablelands Organic matter-mineral complexes Kaolinitic soils C orgânico dissolvido Distribuição de tamanho agregado Tabuleiros costeiros Complexos minerais-minerais orgânicos Solos cauliníticos |
| Sumario: | Extremely kaolinitic soils of Tertiary age elevations on the Brazilian east coast present a wide range of texture, which is recognized as one of the main factors controlling the soil organic matter contents. This study aimed to investigate the organic C storage of different compartments of kaolinitic soils. The studied soils had a wide particle size gradient, were under native forest vegetation, and located on Brazil's eastern coast (Coruripe - CF, Umbaúba - UF, Nova Viçosa - VF, Sooretama - SF, and Itaboraí - IF). The forest cover of all sites allows to record soil properties reference values for a land use condition closer to that of the original sites. We determined soil organic C (SOC) content and SOC stock up to a depth of 1 m, C of topsoil (0.00-0.08 m), aggregate size classes, and dissolved organic carbon (DOC) of the soil surface horizon (A horizon). Soil C stocks at the 0.00-1.00 m depth ranged from 105 to 137 Mg ha−1 and were not regulated by soil texture. The SF soils stored more C up to a depth of 1 m, while lower mean C stocks were found for UF and CF soils. Soil texture was not a reliable index to predict the C contents of the aggregate size classes of the 0.00-0.08 m layer (within each class and in total, using equivalent soil mass of the classes). The most clayey soils had a high percentage of 2-4 mm aggregates and, as a consequence, high aggregate stability indices, which are positively correlated to silt plus clay contents of the soil surface horizon. The proportion of DOC in relation to the total organic C of the surface soil horizon was high for IF and UF areas, which are the less preserved forest fragments among all studied fragments. |
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