Aquífero Aluvionar como suporte à irrigação na bacia hidrográfica do Rio Curu, Ceará

• Autor(a) principal: Silveira, Renata Nayara Câmara Miranda
• Data de Publicação: 2014
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da Universidade Federal do Ceará (UFC)
• Texto Completo: http://www.repositorio.ufc.br/handle/riufc/18082
• topic: Engenharia de água e solo; Aquíferos - Ceará; Bombeamento - Teste; Agricultura irrigada; Groundwater; Pumping test

This research aimed to study the support capacity of shallow tubular wells as a source of water to irrigation in the current conditions of water scarcity in the Curu Irrigated Perimeter - Pentecost, located on the Curu river watershed. After registering the wells, it was done pumping tests in 14 wells, and physicochemical analysis of water, static levels and the elaboration of a groundwater flow network. It was done 14 aquifer tests to obtain the hydrodynamic parameters of saturated soil (hydraulic conductivity, transmissivity and effective porosity).We adopted the method of "auger hole" to obtain the hydraulic conductivity of saturated soil. It was also used the scaled three-step method for the production of 11 wells. Through georeferencing tools to register the water wells and the survey of the water table, we plotted up the data in the flow network map using the Surfer 8.0 software, which allows us to trace the equipotential lines and flow lines. The results led us to the following conclusions: The high variability in flow rates in shallow wells, represented by the high variation coefficient is inherent to the variability characteristics of the alluvial soils layers. The average flow in the studied wells provides support for irrigation of all "agricultural plots" assessed on a daily journey of 12 hours work; Despite the high correlations between flow and hydrodynamic properties of the soil, hydraulic conductivity and transmissivity, the flow estimation through these variables, although salutary because of the savings cost and time to perform the pumping tests, it is not recommended for current conditions of this research, considering the possibility of high relative errors values for some hydraulic conductivity ranges and transmissivity; The time reduction in water distribution flow to the main channels and thus the return flow to Curu river through drains and groundwater discharge are primarily responsible for shaping the equipotential curves generated from the water table. The water quality coming from the shallow wells has no physical and/or chemical limitations for irrigation to the major farming in the Curu Irrigated Perimeter - Pentecost, especially considering the irrigation water system to be practiced, microprinkler, and efficiencies provided, with little significance as aquifer recharge source.