Sabiia Seb
        Busca avançada

Botão Atualizar

Botão Atualizar

Registro completo
Provedor de dados:  Ciência Rural
País:  Brazil
Título:  Carbon stocks in organic matter fractions as affected by land use and soil management, with emphasis on no-tillage effect
Autores:  Bayer,Cimélio
Dick,Deborah Pinheiro
Ribeiro,Genicelli Mafra
Scheuermann,Klaus Konrad
Data:  2002-06-01
Ano:  2002
Palavras-chave:  Soil organic matter
Physical fractionation
Light fraction
Coarse fraction
Resumo:  Land use and soil management may affect both labile and humified soil organic matter (SOM) fractions, but the magnitude of these changes is poorly known in subtropical environments. This study investigated effects of four land use and soil management systems (forest, native pasture, and conventional tillage and no-tillage in a wheat/soybean succession) on (i) total soil organic carbon (SOC) stocks (0 to 250mm depth) and on (ii) carbon (C) stocks in labile (coarse, light) and humified (mineral-associated, humic substances) SOM fractions (0 to 25mm depth), in a Hapludox soil from southern Brazil. In comparison to the adjacent forest site, conventionally tilled soil presented 36% (46.2Mg ha-1) less SOC in the 0 to 250mm depth and a widespread decrease in C stocks in all SOM fractions in the 0 to 25mm depth. The coarse (>53 mum) and light (<1kg dm-3) SOM fractions were the most affected under no-tillage, showing 393% (1.22Mg C ha-1) and 289% (0.55Mg C ha-1) increases, respectively, in relation to conventional tillage. Similar results were observed for mineral-associated SOM and humic substance C pools (34% and 38% increases, respectively) under no-tillage. Compared with labile SOM fraction results, the percentual increments on C stocks in humified fractions were smaller; but in absolute terms this C pool yielded the highest increases (3.06 and 2.95Mg C ha-1, respectively). These results showed that both labile and humified organic matter are better protected under the no-tillage system, and consequently less vulnerable to mineralization. Humified SOM stabilization process involving interactions with variable charge minerals is probably important in maintaining and restoring soil and environmental quality in tropical and subtropical regions.
Tipo:  Info:eu-repo/semantics/article
Idioma:  Inglês
Editor:  Universidade Federal de Santa Maria
Relação:  10.1590/S0103-84782002000300006
Formato:  text/html
Fonte:  Ciência Rural v.32 n.3 2002
Direitos:  info:eu-repo/semantics/openAccess

Empresa Brasileira de Pesquisa Agropecuária - Embrapa
Todos os direitos reservados, conforme Lei n° 9.610
Política de Privacidade
Área restrita

Parque Estação Biológica - PqEB s/n°
Brasília, DF - Brasil - CEP 70770-901
Fone: (61) 3448-4433 - Fax: (61) 3448-4890 / 3448-4891 SAC:

Valid HTML 4.01 Transitional