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| Bayer,Cimélio; Dick,Deborah Pinheiro; Ribeiro,Genicelli Mafra; Scheuermann,Klaus Konrad. |
| 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... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Soil organic matter; Physical fractionation; Light fraction; Coarse fraction; No-tillage. |
| Ano: 2002 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782002000300006 |
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| Pollet,Carolina Schultz; Silva,Leandro Souza da; Chaves,Bruno; Rosa Neto,Lethícia; Dossin,Mariana Ferneda; Giacomini,Sandro José; Cargnelutti Filho,Alberto. |
| ABSTRACT: The state of Rio Grande do Sul has about 20% of the total area as lowland soils, suitable for flooded rice (Oryza sativa). In order to mitigate damage caused by rice monoculture, new crops such as sorghum (Sorghum bicolor) and soybean (Glycine max) have been cultivated in these areas. With different qualities of crop residues, it is expected a change in soil organic matter (SOM) dynamics and consequently, nitrogen (N) availability. The objective of this study was to evaluate the influence of rice, soybean and sorghum crop residues on the N present in physical fractions of SOM of two lowland soils, using labeled 15N technique, under incubation for 180 days in aerobic condition and more 180 days in anaerobic condition. At 30, 180 and 360 days of... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Physical fractionation; Paddy soils; 15N isotope. |
| Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782019000400251 |
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| Signor,Diana; Deon,Magnus Dall’Igna; Camargo,Plínio Barbosa de; Cerri,Carlos Eduardo Pellegrino. |
| ABSTRACT: Soil organic matter (SOM), which influences chemical, physical and biological soil attributes, is the main form of C found in the soil which can also be used as a soil sustainability index. The aim of this study was to use the quantity and quality of SOM as an indicator to determine the sustainability of different land uses (native vegetation, secondary vegetation, fruit orchards, horticultural areas, degraded pasture, improved pasture, and fields with annual crops) in the eastern Amazon. Improved pasture had higher soil C stock than the other land uses and was similar to the native vegetation, and also presented the highest quantity of C in a stable form in the soil (fraction < 53 μm). According to the C management index, improved pasture is... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: C stocks; Changes in land use; Physical fractionation; Carbon management index; Microbial biomass. |
| Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162018000300225 |
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| Zagal,Erick; Córdova,Carolin. |
| Agricultural practices influence the dynamics of soil organic matter (MOS) and its fractions. In this study, the following labile fractions of soil organic matter were determined: free light fraction (FLL), intra-aggregate light fraction (FLI), microbial biomass and mineralized C-CO2, on volcanic soil with different rotations, and later their use was evaluated as biological indicators of the impact of agricultural practices on the soil. The study was carried out in an eight year field experiment, with different productive systems (rotations) in a randomized complete block design. The free light fraction (FLL) was determined by density fractionation with NaI (1.8 g cm-3), and the intra-aggregate light fraction (FLI) was obtained by sonication (1,500 J s-1).... |
| Tipo: Journal article |
Palavras-chave: Free light fraction; Physical fractionation; NaI; Soil microbial biomass; Fumigation-incubation. |
| Ano: 2005 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0365-28072005000200008 |
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