279 resultados para Monoculture
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The objective of this work was to evaluate the performance of Pacific marine shrimp (Litopenaeus vannamei) and tilapia (Oreochromis niloticus), in a polyculture in tanks subjected to different stocking densities and feeding strategies, in comparison with monoculture. Two experiments were performed, at the same time, in a completely randomized design with three treatments and four replicates each. Treatments for experiment I were: monoculture with 10 shrimp per m² (10S:0T); polyculture with 10 shrimp and 0.5 tilapia per m² (10S:0.5T); and polyculture with 10 shrimp and 1 tilapia per m² (10S:1T). Shrimp was the main crop, and feed was provided based on shrimp biomass. Treatments for experiment II were: monoculture with 2 tilapia per m² (2T:0S); polyculture with 2 tilapia and 2.5 shrimp per m² (2T:2.5S); and polyculture with 2 tilapia and 5 shrimp per m² (2T:5S). Tilapia was the main crop, and feed was provided based on fish requirements. In the experiment I, tilapia introduction to shrimp culture resulted in lower shrimp growth and poor feed conversion rate. In experiment II, shrimp introduction to tilapia culture did not interfere with fish performance. Polyculture is more efficient with the combination of 2 tilapia and 2.5 or 5 shrimp per m² and feed based on fish requirements.
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The use of cover crops has been suggested as an effective method to maintain and/or increase the organic matter content, while maintaining and/or enhancing the soil physical, chemical and biological properties. The fertility of Cerrado soils is low and, consequently, phosphorus levels as well. Phosphorus is required at every metabolic stage of the plant, as it plays a role in the processes of protein and energy synthesis and influences the photosynthetic process. This study evaluated the influence of cover crops and phosphorus rates on soil chemical and biological properties after two consecutive years of common bean. The study analyzed an Oxisol in Selvíria (Mato Grosso do Sul, Brazil), in a randomized block, split plot design, in a total of 24 treatments with three replications. The plot treatments consisted of cover crops (millet, pigeon pea, crotalaria, velvet bean, millet + pigeon pea, millet + crotalaria, and millet + velvet bean) and one plot was left fallow. The subplots were represented by phosphorus rates applied as monoammonium phosphate (0, 60 and 90 kg ha-1 P2O5). In August 2011, the soil chemical properties were evaluated (pH, organic matter, phosphorus, potential acidity, cation exchange capacity, and base saturation) as well as biological variables (carbon of released CO2, microbial carbon, metabolic quotient and microbial quotient). After two years of cover crops in rotation with common bean, the cover crop biomass had not altered the soil chemical properties and barely influenced the microbial activity. The biomass production of millet and crotalaria (monoculture or intercropped) was highest. The biological variables were sensitive and responded to increasing phosphorus rates with increases in microbial carbon and reduction of the metabolic quotient.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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The aim of this study was to investigate the effects of acute glyphosate (active ingredient) exposure on the oxidative stress biomarkers and antioxidant defenses of a hybrid surubim (Pseudoplatystoma sp). The fish were exposed to different herbicide concentrations for 96 h. The thiobarbituric acid-reactive substances (TBARS), protein carbonyls and antioxidant responses were verified. The 15 mg a.p L-1 of herbicide resulted in the death of 50% of the fish after 96 h. An increase in liver and muscle TBARS levels was observed when fish were exposed to the herbicide. The protein carbonyl content was also increased in the liver (4.5 mg a.p L-1 concentration) and brain (2.25 mg a.p L-1 concentration). The antioxidant activities decreased in the liver and brain after exposure to herbicide. Levels of ascorbic acid in the liver (2.25 mg a.p L-1 and 4.5 mg a.p L-1 concentrations) and brain (2.25 mg a.p L-1 concentration) were increased post-treatment. Levels of total thiols were increased in the liver and brain (2.25 mg L-1 and 7.5 mg a.p L-1, respectively). Glyphosate exposure, at the tested concentrations affects surubim health by promoting changes that can affect their survival in natural environment. Some parameters as TBARS and protein carbonyl could be early biomarkers for Roundup exposure in this fish species. (C) 2014 Elsevier Inc. All rights reserved.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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The basin of the Corumbataí river is of vital importance to over 600 thousand people, who depend on its waters for consumption. The Simplified Analisys of Environmental Impacts in the Areas Surrounding the Surface Waters of the Drainage Basin of the Corumbataí River (SP) is aimed at defining the areas which are most susceptible to degradation or already damaged and propose engineering solutions according to the environmental problems identified. Using a questionnaire to indicate possible impacts in the surroundings, I related human actions to these damage and quantified them. Having studied the basin extensively and selected 42 areas - generically identified as points and grouped as sub-basins and according to the soil usage -, I was able to identify the main environmental impacts in the basin as: sugar cane monoculture, lack of riparian forest, damaged areas due to mining, the bad state of rural roads and bridges, rubbish disposal alongside roads or directly into the river, accelerated and unplanned expansion of residential and industrial areas into the rural areas and river sources, and Rio Claro's untreated city wastewater
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Sugar cane production is of the utmost importance to the economy of the entire Brazil, due to its multiple utility, being used as the raw material for the manufacture of various items, particularly, sugar and alcohol. In areas of sugarcane monoculture, the appropriate management of soils and water is essential, not only for the maintenance of the quality of the environment, but also for the quality of life of the population. Among the main impacts generated by the cultivation of sugar cane, stands out the withdrawal of the riparian forest, which is essential to the balance and maintenance of the ecosystem. Before that, the present work aimed at mapping the environmentally vulnerable areas in the basin of a tributary of the Corumbataí river, located in the district Santa Olímpia, in the city of Piracicaba-SP. For the purpose, techniques were used in Geoprocessing, aiming to produce thematic maps of Slope, for the Use and Occupation of Land, of Permanent Preservation Areas (APP), Soil and Geological of the basin of interest. From these mappings, the analysis was performed multi-criteria, which resulted in the Map of Environmental Vulnerability. This mapping environmental assessment of the study area, indicating proposals of practices for the management and conservation of soil and water resources, for the purpose of improving the environmental quality of the analyzed area. In this way, the research of this nature, may help in the decision-making on the part of the governmental bodies as well as civil society
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This study sought to address the tourism system in its various strands, compared to socioeconomic and environmental issues. Contextualizing the theme of sustainable tourism, or ecotourism, the reality of the city of Ipeúna, there is the incipient state of efforts in this activity because, predominantly, its territory is occupied by the monoculture of cane sugar and pastures, which damages the maintenance of vegetation fragments, as well as degrading areas that often could take a value tour. Through environmental planning, was intended to raise major issues of interface tourism / environment in order to seek alternatives to the implementation and development of tourism in Ipeúna. As a result, it presents an environmental diagnosis of the study area through which to assess the current status of tourist attractions in relation to environmental and socio-economic dynamics of the city.
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Pós-graduação em História - FCLAS
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Pós-graduação em Ciência Florestal - FCA
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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Pós-graduação em Agronomia (Ciência do Solo) - FCAV
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Pós-graduação em Agronomia (Ciência do Solo) - FCAV
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The research aims to map and understand the SAI- Integrated Agroindustrial System of SEBRAE, topic program directed to small and medium "rural entrepreneurs". The SAI policy seeks targeted result saiming to qualify productive agents (smallholders) to a "mark et under construction". In the study I high light the "production location", as a constituent en vironment with own productive and defining characteristics of this location and of the productive agent. I aim to perceive the location (region of Araraquara) as a topic en vironment of a type of "alternative "agriculture, that in principle is “parallel” to the large hegemonic model of the economies of scale, of monoculture and concentrative, which in the region is taken as that of the "sugarcane industry". I understand the coexistence of these different models as central to understand the development of capitalism, which I treat as "cognitive capitalism".