Aspectos de segurança hídrica em sistemas familiares de produção de morango sob irrigação em Turuçu - RS.

• Autor(a) principal: Fraga, Rosiméri da Silva
• Data de Publicação: 2011
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da UFPel - Guaiaca
• Texto Completo: http://repositorio.ufpel.edu.br/handle/ri/2426
• topic: Fragaria x ananassa; Pequenas barragens de terra; Manejo de irrigação; Qualidade da água; Fragaria x ananassa; Small dams; Irrigation management; Water quality; CNPQ::CIENCIAS AGRARIAS::AGRONOMIA

The strawberry cultivation has been among the main features in family production systems in Turuçu-RS (Brazil), being produced and sold both fresh as well as in the processed form, allowing to the farmers employment generation, income and social inclusion. The strawberry production system, in general, is characterized by the use of soil cover with black color plastic, the use of low tunnels and drip irrigation systems with the fertilizer application through irrigation water (fertigation). The importance and benefits of irrigation for strawberry production have been found by farmers, as it has allowed the improvement of fresh fruits quality. However, as strawberry fields were mostly located far from major water sources, many farmers need to build dams to impound water efficiently, to assure the success of the irrigation for crops, and also to ensure the quality and quantity of water for these activities. Based on this, this study aimed to evaluate: i. spatial and temporal behavior of physical and hydraulic properties of soils in the 0-200 mm layer (available water capacity and water storage) related to irrigation management adopted in 12 crops of strawberry, ii. geotechnical and safety characteristics of two small earth dams used to store water for irrigation of strawberries and other crops, and iii. the existence of correlation between eight water quality parameters with: different types of water sources used for strawberry irrigation; with the micro-regions where they are located; and with the preceding precipitation, referring to 14 rural properties in Turuçu RS (Brazil). Box-plot charts were built to study the spatial and temporal behavior of the available water capacity and of the soil water storage based on the data collected by Bamberg (2010) and on data resulting from the installation of tensiometers at 200 mm depth in the 12 fields. The following activities were conducted in two rural small dams: studies of the embankment geometry, execution of geotechnical tests, assessment of security conditions and the estimative of the project design flood and design of the spillway. Multivariate statistical tools and Pearson correlation analysis were applied to data collected from 2007 to 2008 to identify the existence of correlation between eight water quality parameters (alkalinity, electrical conductivity, biochemical oxygen demand, dissolved oxygen, suspended solids, dissolved solids, total solids and turbidity) with the different types of water sources used for the strawberry irrigation, with the micro-regions where they are located and with the preceding precipitation, referring to 14 rural properties Turuçu-RS. We found that: i. there was not a similar pattern of spatial and temporal behavior for the values of available water capacity and water storage in the soil for the evaluated months, ii. the soil erosion on the upstream slope observed in the embankments is a major problem, since the sediments produced may impair the quality of irrigation water and there is a undersizing of the spillways considering the maximum discharge on the drainage area, and iii. There was strong correlation just between turbidity of the water used in irrigation and the preceding precipitation in some fields.