Análise de redes de distribuição de alta tensão

Tese de mestrado integrado. Engenharia Electrotécnica e de Computadores (Major Energia). Faculdade de Engenharia. Universidade do Porto. 200

Floristic and structural comparisons among palm communities in primary and secondary forest fragments of the Raimundo Irineu Serra Environmental Protection Area - Rio Branco, Acre, Brazil

This study compares the composition and structure of palm communities in fragments of secondary and primary forest within the Raimundo Irineu Serra Environmental Protection Area (APARIS), located at the urban perimeter of Rio Branco, Acre. To evaluate the palm communities, we selected secondary forest areas belonging to three distinct successional stages: 7.5 years; 27.5 years, 37.5 years, and a primary forest fragment. In each forest type we installed five 20 x 20 m plots, where we analyzed floristic composition, vegetation structure, and population demography of all palm species (Arecaceae). In all, we identified 1034 palm individuals, including 12 genera, 19 species. Primary forest exhibited the greatest palm diversity. Structural analysis of each area revealed a scarcity of seedlings (≤ 50 cm tall) and reproductive adults. Fragmentation altered the composition and decreased the richness and diversity of palms within the APARIS, while at the same time, favoring the dominance of certain species, such as A. phalerata.O presente estudo compara a composição e estrutura das comunidades de palmeiras da Área de Proteção Ambiental Raimundo Irineu Serra - APARIS, localizada no perímetro urbano do Município de Rio Branco-Acre. Foram selecionadas três áreas de floresta secundária em estágios sucessionais distintos7,5 anos, 27,5 anos, 37,5 anos de idade, e um fragmento de floresta primária. Em cada área foram instaladas cinco parcelas de 20 X 20m, onde foram analisadas a composição florística, estrutura horizontal e estrutura populacional das palmeiras. Foram identificados 1.034 indivíduos, incluídos em 12 gêneros e 19 espécies de palmeiras. A área de floresta primária apresentou maior diversidade. Na análise da estrutura populacional de cada área, comprovamos a existência de uma escassez de plântulas (≤ 50 cm de altura) e adultos reprodutivos. A fragmentação alterou a composição e diminuiu a riqueza e a diversidade de palmeiras na área da APARIS, enquanto, está favorecendo a dominância de certas espécies como A. phalerata

Organic fertilizer and irrigation in changes the chemical properties of a Fluvent and okra production

The objective of this experiment was to evaluate the effect of organic fertilization on changes of chemical properties of a “Neossolo Flúvico Eutrófico” (Fluvent) and okra production, cultivated with and without mulching and irrigation depths. The experiment was installed in the Agroecology sector at Universidade Estadual da Paraíba. The treatments were designed in a randomized blocks using the 2 x 5 x 2 factorial, which  corresponding to two irrigation depths (100 and 50% of the crop evapotranspiration - ETc), five doses of cattle manure to increase the level from 1.8 % to 2.8; 3.8; 4.8 and 5.8%, in soil with and without mulching (plant residues), with four replications, totaling 80 plots with 27 plants per plot. 140 days after planting okra, soil samples were collected at each plot and chemical analyses were performed. The okra production was evaluated based on the number of green fruits and crop yield. The data were submitted to analysis of variance. The application of cattle manures to the soil between 4.8 and 5.8% and irrigation with 100% of crop evapotranspiration - Etc, with and without mulching, was suitable for the cultivation of okra under semi-arid climatic conditions, which provided increases in the chemical attributes of a Fluvent and in the okra production.The objective of this experiment was to evaluate the effect of organic fertilization on changes of chemical properties of a “Neossolo Flúvico Eutrófico” (Fluvent) and okra production, cultivated with and without mulching and irrigation depths. The experiment was installed in the Agroecology sector at Universidade Estadual da Paraíba. The treatments were designed in a randomized blocks using the 2 x 5 x 2 factorial, which corresponding to two irrigation depths (100 and 50% of the crop evapotranspiration - ETc), five doses of cattle manure to increase the level from 1.8 % to 2.8; 3.8; 4.8 and 5.8%, in soil with and without mulching (plant residues), with four replications, totaling 80 plots with 27 plants per plot. 140 days after planting okra, soil samples were collected at each plot and chemical analyses were performed. The okra production was evaluated based on the number of green fruits and crop yield. The data were submitted to analysis of variance. The application of cattle manures to the soil between 4.8 and 5.8% and irrigation with 100% of crop evapotranspiration - Etc, with and without mulching, was suitable for the cultivation of okra under semi-arid climatic conditions, which provided increases in the chemical attributes of a Fluvent and in the okra production

Lixiviação do sulfentrazone em solos do Norte de Minas Gerais cultivado com cana-de-açúcar

In view of the intense use of herbicides, coupled with the scarcity of information regarding the residual effect of these compounds in some Brazilian soils, the objective of this study was to evaluate the leaching potential by means of biological assays of the sulfentrazone herbicide in the 0- 20 and 20-40 cm of soils of the North of Minas Gerais cultivated with sugarcane. The experiment was conducted in the split - plot scheme, in a completely randomized design. The plots were composed of PVC columns, filled with soils of Salinas (MG) and Pirapora (MG), and the subplots, for 10 depths with intervals of 5 cm (0-5, 5-10, 10-15, 15- 20, 20-25, 25-30, 30-35, 35-40, 40-45 and 45-50 cm). At the top of the columns the dose of 600 g a.i. ha-1 of sulfentrazone was applied and 12 hours later, 60 mm of rainfall was simulated. After 72 hours, the columns were placed horizontally and opened longitudinally, divided into subsections of 5.0 cm. The evaluation of intoxication of the test plants was performed visually at 21 days after sowing, after which the aerial part of the bioindicator plants was cut. Symptoms of sulfentrazone intoxication were observed in the bioindicator plants up to 10 cm deep in the superficial layer (0-20 cm) and up to 15 cm in the deepest layer (20-40 cm) of both soils. In the two soil layers the sulfentrazone was detected in a higher concentration in the first five centimeters. Greater mobility of the herbicide was verified in the deeper layer of the soil (20-40 cm) indicating a greater leaching potential of the herbicide under these conditions.Diante da intensa utilização de herbicidas, aliada à escassez de informações referentes ao efeito residual desses compostos em alguns solos brasileiros, objetivou-se neste trabalho avaliar o potencial de lixiviação por meio de ensaios biológicos, do herbicida sulfentrazone, nas camadas de 0-20 e 20-40 cm de solos do Norte de Minas Gerais cultivado com cana-de-açúcar. O experimento foi conduzido no esquema de parcelas subdivididas, no delineamento inteiramente casualizado. As parcelas foram compostas por colunas de PVC, preenchidas com solos de Salinas (MG) e Pirapora (MG), e as subparcelas, por 10 profundidades com intervalos de 5 cm (0-5, 5-10, 10-15, 15-20, 20-25, 25-30, 30-35, 35-40, 40-45 e 45-50 cm). No topo das colunas, aplicou-se a dose de 600 g ha-1 i.a sulfentrazone e, 12 horas depois, simulou-se 60 mm de precipitação pluviométrica. Após 72 horas, as colunas foram colocadas na posição horizontal e abertas longitudinalmente, divididas em subseções de 5,0 cm. A avaliação da intoxicação das plantas-teste foi realizada visualmente aos 21 dias após a semeadura destas, posteriormente foi feito o corte da parte aérea das plantas bioindicadoras. Foram observados sintomas de intoxicação do sulfentrazone nas plantas bioindicadoras até 10 cm de profundidade na camada superficial (0-20 cm) e até 15 cm na camada mais profunda (20-40 cm) de ambos os solos. Nas duas camadas de solo o sulfentrazone foi detectado em maior concentração nos primeiros cinco centímetros. Maior mobilidade do herbicida foi verificada na camada mais profunda do solo (20-40 cm) indicando maior potencial de lixiviação do herbicida nestas condições

Pineapple intercropped systems as an income alternative during the formation of irrigated coffee crop

O objetivo deste trabalho foi determinar o sistema de plantio de abacaxizeiro intercalado com cafeeiro que proporciona o maior retorno econômico, sem comprometer o desenvolvimento vegetativo e a produtividade de cafezal irrigado. Utilizou-se o delineamento em blocos ao acaso, com quatro repetições e dez plantas úteis por parcela. Os sistemas irrigados de cultivo consistiram em: duas e três fileiras simples de abacaxizeiro, nas entrelinhas do cafeeiro, ou quatro linhas em fileiras duplas. O desenvolvimento vegetativo do cafeeiro foi avaliado aos 6, 12 e 18 meses após o plantio, e a produtividade aos 28 meses. O cultivo de duas fileiras simples favoreceu o desenvolvimento do cafeeiro, e os demais sistemas não tiveram efeito sobre esse parâmetro. A produtividade do cafeeiro foi maior nos sistemas de cultivo com duas e três fileiras de abacaxi. Os três sistemas de cultivo apresentaram retornos econômicos positivos. O sistema intercalar com três fileiras simples proporciona o melhor retorno, sem comprometer o desenvolvimento vegetativo e a produtividade do cafeeiro.The objective of this work was to determine the planting system of pineapple intercropped with coffee plants that provides the highest economic return, without harming the vegetative development and yield of the irrigated coffee crop. A randomized complete block design was used, with four replicates and ten useful plants per plot. The irrigated cropping systems consisted of two and three single rows of pineapple between coffee rows, or of two double rows of pineapples. Vegetative development of the coffee plants was evaluated at 6, 12, and 18 months after planting, and the coffee yield at 28 months. Cultivation of two single rows of pineapple improved coffee development, and the other planting systems did not harm coffee development. Coffee yield was greater in the cropping systems with two and three intercropped rows of pineapples. The three planting systems had positive economic return. The system with three single rows provide the best economic return, without compromising the vegetative growth and yield of coffee plants