Utilização de modelagem numérica na avaliação do bulbo úmido no solo em irrigação subsuperficial

• Autor(a) principal: Rocha, Mayara Oliveira
• Data de Publicação: 2019
• 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/51242
• topic: Caracterização física do solo; Modelagem numérica; Irrigação subsuperficial; Physical characterization of the soil; Numerical modeling; Subsurface irrigation

The study of the soil and its physical-hydric properties is extremely important for the design and management of irrigation systems. The determination and use of properties such as density, porosity, hydraulic conductivity of saturated and unsaturated soil, soil water retention curve is essential, as it intervenes in soil-water interactions and influences various processes in the soilwater- plant- atmosphere system, such as the capacity of the soil to store and make water available to plants, in addition to the movement of water in the soil. The dynamics of water in unsaturated soil is a complex process explained by the Richards equation, and because it is a non-linear differential equation, it does not have an analytical solution requiring the use of the finite element method, for example, to obtain solutions. Therefore, as a faster and more accurate solution, the option is to use numerical software that solves the Richards equation through the finite element method, supporting technicians and irrigators by simulating different models of water distribution in the soil according to the conditions stipulated by them. This work was divided into three chapters whose objectives were to perform a numerical modeling of subsurface irrigation, using physical-hydric properties of the soil (density, porosity, hydraulic conductivity of the saturated soil and soil water retention curve) and parameters of the water system irrigation (different drip tube installation depths and different spacing between emitters) with later model validation using data obtained in a field experiment set up at the Federal University of Ceará, Campus do Pici with AG 1051 corn hybrid through regression analysis with soil moisture data, obtained with thermogravimetric method, with calculation of the coefficient of determination (R2) and root of the mean square error (RMSE). In addition to the agronomic and productive behavior of the crop, analyzed with the aid of descriptive statistics and analysis of variance. The physical-hydric characteristics were determined and used to create the model and this proved to be applicable for the design and management of subsurface irrigation systems, varying the depth of installation of the drip tube, the spacing between emitters and the soil moisture, with good results for the different simulated scenarios. In addition, it was possible to conclude that subsurface irrigation is a viable alternative with good agronomic and productive results for the hybrid corn crop AG 1051, recommending a better drip tube installation depth and a better spacing between emitters for the crop.