Raimundo Rodrigues Gomes Filho

Chuvas intensas no Estado da Bahia

Series historicas de precipitacao pluvial de 19 estacoes pluviograficas localizadas no Estado da Bahia e operadas pela Agencia Nacional de Energia Eletrica (ANEEL), foram analisadas, objetivando-se ajustar modelos teoricos de distribuicao de probabilidade aos dados de chuvas intensas e estabelecer a relacao entre intensidade, duracao e frequencia da precipitacao pluvial. Para cada estacao pluviografica determinaram-se as series de intensidade maxima anual das precipitacoes com duracoes de 10, 20, 30, 40, 50, 60, 120, 180, 240, 360, 720 e 1.440 min. Os modelos probabilisticos testados foram os de Gumbel, Log-Normal a dois e tres parâmetros, Pearson e Log-Pearson III. As equacoes de intensidade-duracao-frequencia da precipitacao pluvial foram ajustadas utilizando-se o metodo de regressao nao-linear de Gauss-Newton. O teste de aderencia de Kolmogorov-Smirnov, utilizado para a verificacao do ajuste dos modelos aos dados de chuvas intensas, evidenciou que o modelo de Gumbel foi o que melhor se ajustou para a maior parte das combinacoes entre estacoes pluviograficas e duracoes estudadas. Foram evidenciadas, para uma mesma duracao, grandes variacoes nas intensidades de precipitacao entre as estacoes estudadas.

Remoção de carga orgânica e produtividade da aveia forrageira em cultivo hidropônico com águas residuárias da suinocultura

A study to quantify the productivity of forage oat and the efficiency in the removal of the organic load of swine wastewater, used in different proportions for composition of the nutritive solution for the hydroponic cultivation, was accomplished inside a shed, containing individualized systems of cultivation, in tanks of 3.20 x 0.80 m, equipped with aeration systems. The proportions of 70, 50, 30 and 10% of swine wastewater were used in the preparation of the nutritive solution, represented by values of initial electrical conductivity of 4.2, 2.8, 1.8 e 0.97 dS m-1. The oat was sown on a plastic screen inside the cultivation tanks. The concentration of dissolved oxygen, the electrical conductivity and the temperature of both the nutritive solutions and the air inside the shed were monitored daily, while samples of the solutions were collected weekly for determination of the concentration of COD and BOD. A treatment was used with a conventional nutritive solution as the control. The forage oat cultivated in a hydroponic system, with the use of swine wastewater in the preparation of the nutritive solution, provided productivities of up to 31.5 t ha-1 y-1 and significant decrease of the organic load of the nutritive solution.

IRRIGAR – APLICATIVO COMPUTACIONAL PARA O DIMENSIONAMENTO ECONÔMICO DE SISTEMAS DE IRRIGAÇÃO POR ASPERSÃO CONVENCIONAL

This paper describes the techniques and methods used in the development of IRRIGATE application using object-oriented programming using Microsoft Visual Basic for Applications 8.0 compiler (VBA), a specific program for the development of conventional sprinkler irrigation projects that have the purpose of facilitating the economic design of systems that use electrical energy distribution Brazilian dealer network. The application supports the agronomic and operating system design and allows the definition of the layout of irrigation. Continuous load losses are determined by universal Darcy-Weissbach and the localized estimated or calculated by the direct method. The sidelines are scaled by the criterion of maximum permissible load loss and the other lines of the system by cost analysis with the help of Bresse equation. This program is a tool that can be used as a direct contribution to the increase of economic efficiency of irrigation by sprinkler systems, helping to enable the use of this method in agriculture and the rational use of inputs involved.