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Registros recuperados: 23 | |
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Gubiani,Paulo Ivonir; Jong Van Lier,Quirijn de; Reichert,José Miguel; Goulart,Rafael Ziani; Fontanela,Eracilda. |
ABSTRACT: During linear deformation (h) in a soil sample, the variation of the void ratio with respect to deformation (dε/dh) and the respective variation of soil bulk density (dρ/dh) are identical only for a specific value of h. Consequently, if two compression curves are drawn for the same soil sample, one using ρ and the other using ε, there are differences in both the calculated precompression stress (σp) and compression index (Ic). In this study, we highlight the causes by a mathematical analysis and an experimental investigation, quantifying the differences in σp and Ic when using ε and ρ. σp and Ic were calculated for 103 compression curves of an ultisol and 193 of an oxisol. The σp (kPa) using ρ (σpρ) was greater than when using ε (σpε), and... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Void ratio; Particle density; Soil bulk density. |
Ano: 2016 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782016000100076 |
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Drescher,Marta Sandra; Reinert,Dalvan José; Denardin,José Eloir; Gubiani,Paulo Ivonir; Faganello,Antônio; Silva,Bernardo Rodrigues da; Zardin,Maísa Carina. |
ABSTRACT: Intensification of soil compaction process under no-tillage (NT) is motivating the search for alternatives to mitigate soil compaction state. This study evaluated changes in soil physical and hydraulic properties caused by seeder with fertilizer shanks at different depths compared with the double discs lagged seeder, to investigate the possibility of soil decompaction by sowing under NT in southern Brazil. The study was conducted in a clayed Oxisol, for 27 years under NT. Treatments were three planting mechanisms: S0.10m: cutting disc combined with shank acting to 0.10m depth; S0.15m: cutting disc combined with shank acting to 0.15m depth and, D0.07m: double discs lagged acting to 0.07m depth in an experimental randomized block design with four... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Soil management; Mechanical decompaction; Soil structure recovery. |
Ano: 2017 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782017000300252 |
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Registros recuperados: 23 | |
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