Data/hora: 03/06/2024 11:00:59

Provedor de dados: | Revista Brasileira de Ciência do Solo
País: | Brazil
Título: | Compressibility of Oxisol aggregates under no-till in response to soil water potential
Autores: | Tavares Filho,João; Tessier,Daniel.
Data: | 2009-12-01
Ano: | 2009
Palavras-chave: | Edometric assay; Void index; Total porosity; Soil compression; Soil compaction.
Resumo: | The system of no-till sowing stands out as being a technology that suits the objectives of more rational use of the soil and greater protection against the erosion. However, through till, any of it, occurs modifications of the soil's structure. This current work aims to study the influence of the energy state of the water and of the organic matter on the mechanism of compaction of Red Oxisol under no-till management system. Humid and non-deformed sample were collected in horizon AP of two agricultural areas under no-till, with and without rotation of cultures. In the laboratory, these samples were broken into fragments and sifted to obtain aggregates of 4 to 5 mm sized, which were placed in equilibrium under four matrix potentials. Thereafter, they were exposed to uni-dimensional compression with pressures varying from 32 to 1,000 kPa. The results in such a way show that the highest compressibility of aggregates both for the tilling with rotation of cultures as for the tilling without rotation of cultures, occurred for matrix potential -32 kPa (humidity of 0.29-0.32 kg kg-1, respectively), while the minor occurred for the potentials of -1 and -1,000 kPa (humidity of 0.35 and 0.27 kg kg-1, respectively), indicating that this soil should not be worked with humidity ranging around 0.29 to 0.32 kg kg-1 and the highest reduction of volume of aggregates was obtained for the mechanical pressures lower than 600 inferior kPa, indicating that these soils showed to be very influenced by compression, when exposed to mechanical work. Also, the aggregates of soil under no-till and rotation of crops presented higher sensitivity to the compression than the aggregates of soil under no-till and without rotation of crops, possibly for having better structural conditions given to a higher content of organic matter.
Tipo: | Info:eu-repo/semantics/article
Idioma: | Inglês
Identificador: | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832009000600002
Editor: | Sociedade Brasileira de Ciência do Solo
Relação: | 10.1590/S0100-06832009000600002
Formato: | text/html
Fonte: | Revista Brasileira de Ciência do Solo  v.33 n.6 2009
Fonte: | info:eu-repo/semantics/openAccess