Data/hora: 13/06/2024 04:40:53

Provedor de dados: | 90
País: | Brazil
Título: | Distribution and vertical stratification of carbon and nitrogen in soil under different managements in the pampean region of Argentina
Autores: | Álvarez,Carina Rosa; Costantini,Alejandro Oscar; Bono,Alfredo; Taboada,Miguel Ángel; Boem,Flavio Hernán Gutiérrez; Fernández,Patricia Lilia; Prystupa,Pablo.
Data: | 2011-12-01
Ano: | 2011
Palavras-chave: | No-tillage; Soil organic matter fractions; Tillage systems; Carbon stratification; C and N stocks.
Resumo: | One of the expected benefits of no-tillage systems is a higher rate of soil C sequestration. However, higher C retention in soil is not always apparent when no-tillage is applied, due e.g., to substantial differences in soil type and initial C content. The main purpose of this study was to evaluate the potential of no-tillage management to increase the stock of total organic C in soils of the Pampas region in Argentina. Forty crop fields under no-tillage and conventional tillage systems and seven undisturbed soils were sampled. Total organic C, total N, their fractions and stratification ratios and the C storage capacity of the soils under different managements were assessed in samples to a depth of 30 cm, in three layers (0-5, 5-15 and 15-30 cm). The differences between the C pools of the undisturbed and cultivated soils were significant (p &lt; 0.05) and most pronounced in the top (0-5 cm) soil layer, with more active C near the soil surface (undisturbed &amp;gt; no-tillage &amp;gt; conventional tillage). Based on the stratification ratio of the labile C pool (0-5/5-15 cm), the untilled were separated from conventionally tilled areas. Much of the variation in potentially mineralizable C was explained by this active C fraction (R² = 0.61) and by total organic C (R² = 0.67). No-till soils did not accumulate more organic C than conventionally tilled soils in the 0-30 cm layer, but there was substantial stratification of total and active C pools at no till sites. If the C stratification ratio is really an indicator of soil quality, then the C storage potential of no-tillage would be greater than in conventional tillage, at least in the surface layers. Particulate organic C and potentially mineralizable C may be useful to evaluate variations in topsoil organic matter.
Tipo: | Info:eu-repo/semantics/article
Idioma: | Inglês
Identificador: | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832011000600015
Editor: | Sociedade Brasileira de Ciência do Solo
Relação: | 10.1590/S0100-06832011000600015
Formato: | text/html
Fonte: | Revista Brasileira de Ciência do Solo  v.35 n.6 2011
Fonte: | info:eu-repo/semantics/openAccess