Modelos de capacidade de suporte de carga de um Latossolo submetido a diferentes sistemas de manejo de plantas daninhas em lavoura cafeeira
Data
2007-02-14
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Universidade Federal de Lavras
Resumo
A determinação das pressões que podem ser aplicados aos solos submetidos a diferentes sistemas de manejo de plantas daninhas é importante para adaptar o manejo de lavouras cafeeiras de forma sustentável Os objetivos deste estudo foram a) desenvolver modelos de capacidade de suporte de carga (CSC) para um Latossolo Vermelho-Amare10 (LVA) cultivado com cafeeiros e submetido a diferentes sistemas de manejo das plantas daninhas; b) determinar, através do uso destes modelos, as pressões que podem ser aplicadas ao solo para evitar a compactação; c) identificar 0 sistema de manejo de plantas daninhas mais resistente ou mais suscetível a compactação. submetido a diferentes sistemas de manejo das plantas daninhas. O estudo foi conduzido na fazenda da Epamig, no município de Patrocínio, MG, em uma lavoura plantada com a cultivar Rubi 1192 no espaçamento 3,8 x 0,7 m. Os manejos avaliados foram os seguintes entrelinha sem capina (SC); capina manual (CM); herbicida de pós- emergência (HPÓS) e herbicida de pré-emergência (HPRÊ) e na projeção da saia do cafeeiro roçacarpa (RÇ); capina manual (CM); herbicida de pós- emergência (HPÓS) e herbicida de pré-emergência (HPRÉ). Em cada condição de manejo, foram amostradas aleatoriamente nas profundidade 0-3, 10-13 e 25- 28 cm, 15 amostras indeformadas, totalizando 900 amostras [15 amostras x 3 profundidades x 20 (4 manejos no centro da entrelinha + 16 na projeção da saia do cafeeiro)]. As amostras indeformadas foram utilizadas no ensaio de compressão uniaxial para a obtenção da pressão de preconsolidação (cp) e densidade do solo inicial (Dsi). Determinaram se no excedente das amostras indeformadas textura, matéria orgânica (MO), densidade de partículas (Dp), volume total de poros (VTP), capacidade de campo (CC), ponto de murcha permanente (PMP) e óxidos. No centro da entrelinha, 0 manejo mais susceptível à compactação foi o HPRÉ na profundidade de 25-28 cm e, o mais resistente à compactação, HPRÉ profundidade de 0-3 cm. O manejo RÇ na projeção da saia foi o mais susceptível à compactação na profundidade de 0-3 cm e os manejos HPÓS e HPRÉ os mais resistentes. Para a profundidade de 10-13 cm na projeção da saia, 0 HPRÉ foi mais resistente à compactação e a RÇ e a CM e o HPÓS os mais susceptíveis. Na profundidade de 25-28 cm, o HPRÉ na projeção da saia associado com 0 HPÓS na entrelinha foi 0 mais resistente à compactação e 0 HPÓS na projeção da saia associado com a CM na entrelinha com 0 mais susceptível Para estimar a densidade do solo acima da qual o solo está compactado, foi obtida a seguinte equação DSCp = 1,12 x Dsi. Para as condições que este trabalho foi desenvolvido, recomenda-se, como manejo ideal a utilização de HPÓS na entrelinha associado aos manejos HPRÉ e HPÓS na saia do cafeeiro.
The determination of the pressures that can be applied to the soils submitted to different weed management systems is important to adapt the coffee crop management in a sustainable way. The objectives of this study were a) to develop the bearing capacity models for a Red-Yellow Latossol (LVA) cultivated with coffee and submitted to different weed management systems; b) to determine through the use of these models the pressures that can be applied to the soils to avoid the soil compactiom c) to identify the weed management system more resistant or susceptible to soil compaction. This study was carríed out in the experimental farm of Epamig in the Patrocínio County, MG, in a farming planted with Ruby 1192 coffee variety in 3,8 x 0,7 m spacíng The weed management systems studied were in the inter rows Without hoeing (SC), hand hoeing (CM), post-emergence herbicide (HPÓS) and pre-emergence herbicide (HPRÉ) and in the canopy of the coffee plant roçacarpa (RÇ), hand hoeing (CM), post-emergence herbicide (HPÓS) and pre-emergence herbicide (HPRÊ). In each manegement system 15 undisturbed samples, were collected randomly at 0-3, 10-13 and 25-28 cm depth, totaling 900 soil samples [15 samples x 3 depths X 20 (4 weed manegement systems in the inter rows + 16 under cannopy of the coffee plant)]. The undisturbed soil samples were used in the uniaxial compression test to obtain the preconsolidation pressure (cp) at different moisture content and initial bulk density (Dsi). From the surplus of the undisturbed soíl samples it was determined the texture, the organic matter (MO), the particle density, the total porosity (VTP), the ñeld capacity (CC), the permanent Wilting point (PMP) and the oxides. In the inter rows the weed management system more susceptible to soil compaction was the HPRÉ at 25- 28 cm depth While the HPRÉ at 0-3 cm was the most resistant. Under the canopy the RÇ was most susceptible to soil compaction at of 0-3 cm depth and the HPÓS and the HPRÉ, the most resistant. At 10-13 cm depth under the canopy the HPRÉ was most resistant to compaction and the RÇ and the CM and the HPÓS the most susceptible to soil compaction. At 25-28 cm depth, the HPRÉ under the canopy associated With the HPÓS in the inter rows was the most resistant to compaction, While the manegement HPÓS under the canopy associated With the CM in the inter rows the most susceptible. To estimate the bulk density above Wich the soíl is compacted, the following equation was obtained Dscp = 1,12 x Dsi. For the conditions that this Work Was developed it ís recommended as an ideal Weed management the use of the HPÓS in of the inter rows associated With the HPRÉ and the HPÓS in the canopy of the coffee plant.
The determination of the pressures that can be applied to the soils submitted to different weed management systems is important to adapt the coffee crop management in a sustainable way. The objectives of this study were a) to develop the bearing capacity models for a Red-Yellow Latossol (LVA) cultivated with coffee and submitted to different weed management systems; b) to determine through the use of these models the pressures that can be applied to the soils to avoid the soil compactiom c) to identify the weed management system more resistant or susceptible to soil compaction. This study was carríed out in the experimental farm of Epamig in the Patrocínio County, MG, in a farming planted with Ruby 1192 coffee variety in 3,8 x 0,7 m spacíng The weed management systems studied were in the inter rows Without hoeing (SC), hand hoeing (CM), post-emergence herbicide (HPÓS) and pre-emergence herbicide (HPRÉ) and in the canopy of the coffee plant roçacarpa (RÇ), hand hoeing (CM), post-emergence herbicide (HPÓS) and pre-emergence herbicide (HPRÊ). In each manegement system 15 undisturbed samples, were collected randomly at 0-3, 10-13 and 25-28 cm depth, totaling 900 soil samples [15 samples x 3 depths X 20 (4 weed manegement systems in the inter rows + 16 under cannopy of the coffee plant)]. The undisturbed soil samples were used in the uniaxial compression test to obtain the preconsolidation pressure (cp) at different moisture content and initial bulk density (Dsi). From the surplus of the undisturbed soíl samples it was determined the texture, the organic matter (MO), the particle density, the total porosity (VTP), the ñeld capacity (CC), the permanent Wilting point (PMP) and the oxides. In the inter rows the weed management system more susceptible to soil compaction was the HPRÉ at 25- 28 cm depth While the HPRÉ at 0-3 cm was the most resistant. Under the canopy the RÇ was most susceptible to soil compaction at of 0-3 cm depth and the HPÓS and the HPRÉ, the most resistant. At 10-13 cm depth under the canopy the HPRÉ was most resistant to compaction and the RÇ and the CM and the HPÓS the most susceptible to soil compaction. At 25-28 cm depth, the HPRÉ under the canopy associated With the HPÓS in the inter rows was the most resistant to compaction, While the manegement HPÓS under the canopy associated With the CM in the inter rows the most susceptible. To estimate the bulk density above Wich the soíl is compacted, the following equation was obtained Dscp = 1,12 x Dsi. For the conditions that this Work Was developed it ís recommended as an ideal Weed management the use of the HPÓS in of the inter rows associated With the HPRÉ and the HPÓS in the canopy of the coffee plant.
Descrição
Dissertação de Mestrado defendida na Universidade Federal de Lavras
Palavras-chave
Pressão de preconsolidação, Resistência e susceptibilidade, Compactação do solo, Manejo do solo, Compressão uniaxial, Produção dos cafeeiros
Citação
ARAUJO JUNIOR, C. F. Modelos de capacidade de suporte de carga de um Latossolo submetido a diferentes sistemas de manejo de plantas daninhas em lavoura cafeeira. 2007. 132 f. Dissertação (Mestrado em Ciência do Solo) - Universidade Federal de Lavras, Lavras. 2007.