Diagnóstico ambiental da área de influência do complexo sucroalcooleiro Usina Vale do São Simão Ltda

One of the most widespread renewable energy sources in Brazil is ethanol, from sugarcane, therefore, the sugar and alcohol sector is expanding, with positive impacts for the economy of the country. Sugar cane was introduced in Brazil as a crop during its colonization, for the production of sugar, and put the country in the global scenario. The expansion of this crop occurred in the seventies, to reduce the reliance in fossil energy sources and to stimulate the development of the agricultural activity. Thus, the federal government has promoted the sugar cane crop and the production of ethanol as a fuel. However, it is important to minimize possible impacts that the crop may cause to the environment. Sugar cane has expanded in the frontiers of the mesoregion of Triângulo Mineiro and Alto Paranaíba-MG, and, in this perspective, the agroindustrial complex known as Companhia Energética Vale do São Simão Ltda., with the Mill located in the county of Santa Vitória, Minas Gerais, was adopted to evaluate the environmental impacts caused by the sugarcane in the area of influence of the mill. The mill has a polygonal area corresponding to 53,525.20 hectares, and for its establishment a Study and Report of Environmental Impacts (EIA/RIMA) was presented, as required as an environment protection instrument by the Environment National Policy (Law nº 6.938/81), and detailed by the Resolution CONAMA nº 01/1986. These studies pointed that native vegetation fragments in the Area of Influence of the Mill, before its implantation, corresponded to approximately 20.7% of the area. Therefore, this study evaluated the impacts of the installation of Usina Vale do São Simão, between 2007 and 2012, determining its reflex on the environmental regularization of the farms, and the vegetation fragments existing in the area, in the recovery and recomposition of areas defined as Legal Reserve and Permanent Preservation. Previous studies of the area were analyzed, soil use and occupation was mapped for the years 2007 and 2012, and the areas of permanent preservation and native vegetation fragments were marked. In general, there was a decline in native vegetation coverage in the period, although it cannot be stated that such reduction was a direct effect of the milling activity. Therefore, the legal requirement of preserving such areas was not capable of bringing the positive effects of protection and recovery as demanded by the Law, highlighting that the current legislation was not enough to protect such areas.

Resposta da batata cv. Cupido à fertilização organomineral

Potato crop cycle is relatively short and presents high yield per area; therefore, it is a very demanding culture for available nutrients in the soil solution. Despite its importance and the large number of studies about the crop, there is little research on plant nutrition regarding the use of organomineral fertilizer. This study evaluated potato, cv. Cupid, development and productivity as a function of fertilization with pelletized organomineral fertilizer. The experiment was done in Perdizes, Minas Gerais, in the rainy season of 2014/2015. The experimental design was a randomized blocks, with factorial arrangement of 4 x 2 (doses x management) and a control with mineral fertilizer, with 3 repetitions. Organomineral fertilizer doses were 25, 50, 75 and 100% of the conventional mineral dose, which was 600 kg ha-1 K2SO4, 850 kg ha-1 NH4H2PO4, and 300 kg ha-1 (NH4)2SO4 of topdressing 19 days after planting (DAP). Fertilization managements were with or without topdressing at 19 DAP, when the potato was hilled. Two plants per plot were sampled at 36, 50, 64 and 81 DAP and analyzed for leaf, stem and dry matter contents. DRIS - Diagnosis and Recommendation Integrated System was applied at 36 DAP and the potatoes were harvested 112 DAP and subjected to tuber classification. Throughout the cycle, stem, leaf and tuber dry mass showed no significant differences between the fertilization managements. The doses of organomineral fertilizer and topdressing management does not affect productivity, and the lower doses (25%) were similar the greater ones and the control, with an average of 16.8 t ha-1, demonstrating that it is viable to make a single application of organomineral fertilizer at planting due to operational efficiency. The low yields observed were due to high rainfall and temperature, creating favorable conditions for the incidence of pests and diseases. According to DRIS, the organomineral dose 75% for topdressing, presented the best nutritional balance.