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URI permanente desta comunidadehttps://thoth.dti.ufv.br/handle/123456789/3352
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Resultados da Pesquisa
Item Structural quality of soils cultivated with coffee and pasture in an environmental protection area(Sociedade Brasileira de Ciência do Solo, 2010-05) Lima, Vico Mendes Pereira; Magalhães, Ciro Augusto de Souza; Oliveira, Geraldo César de; Lima, José Maria deStudies of soils in Environmental Protection Areas (EPAs) are of great importance, because they are an essential component of ecosystems, directly interfering in environmental sustainability. The objective of this study was to evaluate the structural quality of soil cultivated with coffee and used as pasture in the Capituva’s River microbasin, which is located in the Environmental Protection Area in Coqueiral, south of the state of Minas Gerais. Uniaxial compression test (preconsolidation test) and soil resistance to penetration were used. Undisturbed samples were taken from the surface layer (0–5 cm) of the soils in the area: a typic dystrophic Red Latosol (LVd - Oxisol), a typic eutrophic Red Argisol (PVe - Ultisol), and a typic dystrophic Haplic Cambisol (CXbd - Inceptisol). A significant linear positive correlation was observed between the results of the preconsolidation test and soil resistance to penetration. Load bearing capacity of soil could be estimated accordingly by means of penetration resistance for LVd, PVe, and CXbd. Cambisol - CXbd showed lower loading support capacity and resistance to penetration than LVd and PVe, due to the better crop management in this soil that resulted in higher physical quality which accounts for higher production and environmental sustainability.Item Seasonal change of soil precompression stress in coffee plantation under sub-humid tropical condition(Editora UFLA, 2014-04) Iori, Piero; Dias Junior, Moacir de Souza; Ajayi, Ayodele Ebenezer; Guimarães, Paulo Tácito Gontijo; Souza, Zélio Resende de; Figueiredo, Vanessa CastroThe objective of this study was to describe the seasonal change of precompression stress behavior in coffee plantations in the sub-humid tropic zone of Brazil as affected by agriculture traffic associated with the time since the establishment the coffee plantation, field slope, sampling position in and sampling depths. The coffee plantations on a uniform soil type; Red-Yellow Latosol were aged 2, 7, 18 and 33 years. Areas with side slope of 3, 9 and 15% were selected in these coffee plantations for this study. The soil was sampled at three positions on the coffee plantation row (bottom of traffic line, inter-row and top of traffic line) and at two depths (topsoil and sub-surface). Samples were collected over a one year period for each month of year. The study showed that the time since the establishment of a coffee farm and the slope steepness had significant effect on soil disturbance in mechanized operation. The coffee plantation with longer establishment time and on steeper terrain had higher precompression stress. The top traffic line presented higher load-bearing capacity than inter-row and bottom traffic line. The sites were more susceptible to compaction in the period from November to January of the year , because the Red-Yellow Latosol presented lower load-bearing capacity than the stress applied by tractor used in coffee management practices.Item Suscetibilidade à compactação de um latossolo vemermelho-amarelo submetido a diferentes métodos de controle de plantas invasoras, na cultura cafeeira(Editora UFLA, 2010-05) Santos, Gislene Aparecida dos; Dias Junior, Moacir de Souza; Guimarães, Paulo Tácito Gontijo; Pais, Paula Sant’Anna MoreiraObjetivou-se, neste estudo: a) desenvolver modelos de capacidade de suporte de carga (CSC), para um LVA cultivado com cafeeiro, em função dos métodos associados de controle de plantas invasoras, pressão de preconsolidação e umidade b) identificar, através do uso desses modelos, o método de controle mais resistente e mais suscetível à compactação, nas entrelinhas (EL) e linhas de tráfego (LT). O estudo foi conduzido na Fazenda Experimental da EPAMIG de Patrocínio MG, em uma lavoura cafeeira (Coffea arabica L.). Os métodos de controle utilizados foram: nas entrelinhas - enxada rotativa, grade de disco, roçadora e sem capina (testemunha). Para cada condição de manejo, coletou-se nas profundidades 0-3, 10-13 e 25-28 cm, 15 amostras para gerar o modelo de CSC, tanto nas EL como nas LT, totalizando 315 amostras, com exceção do método sem capina, em que foi realizado apenas nas entrelinhas. Para a obtenção dos modelos, as amostras com diferentes umidades foram submetidas ao ensaio de compressão. Nas EL, a enxada rotativa, roçadora e grade de discos nas profundidades 0-3, 10-13 e 25-28 cm promoveram compactação do solo, enquanto que a grade de discos, nas mesmas profundidades, proporcionou um alívio da resistência mecânica do solo. Na LT, como método de controle a enxada rotativa, na profundidade de 0-3 cm foi o método de controle mais susceptível à compactação do solo; na profundidade 10-13 cm, quando foi utilizada a enxada rotativa, a grade de discos e a roçadora promoveram compactação do solo; na profundidade 25-28 cm, uma maior suscetibilidade à compactação foi promovida quando utilizou-se a roçadora.