Desempenho do irrigâmetro no manejo da irrigação no Perímetro Irrigado do Jaíba, MG, Brasil

Abstract

RESUMOObjetivou-se neste trabalho determinar o coeficiente do irrigâmetro (K I ), assim como avaliar o desempenho do irrigâmetro utilizado no manejo da irrigação do girassol. O experimento foi conduzido no Perímetro Irrigado do Jaíba, em Jaíba, MG, a 15° 36' de latitude Sul e 43° 42' de longitude Oeste, com altitude de 460 m. Na avaliação de desempenho do irrigâmetro ajustado nas alturas 1, 2, 3, 4, 5 e 6 cm do nível de água no evaporatório, comparou-se a evapotranspiração estimada pelo aparelho e a evapotranspiração de referência, calculada pelo método padrão de Penman-Monteith FAO 56 (Allen et al., 1998). Concluiu-se então que os valores de K I obtidos foram 0,42, 0,69, 0,85, 1,07, 1,34 e 1,61 para alturas dos níveis de água do evaporatório iguais a 1, 2, 3, 4, 5 e 6 cm, respectivamente. Não houve diferença significativa entre a produtividade do girassol irrigado no período diurno, e irrigado no período noturno, sendo encontradas médias superiores que na literatura. O irrigâmetro mostrou-se satisfatório no manejo da irrigação e para obter a estimativa da evapotranspiração de referência nas condições climáticas da região, recomendase a utilização do aparelho equipado com evaporatório ajustado no nível 3,7 cm.Palavras-chave: Agricultura irrigada; produtividade do girassol; eficiência de irrigação.Performance of the irrigameter in management of irrigation in the Jaíba Irrigated Perimeter, MG, Brazil ABSTRACTThe objective of this study was to determine the coefficient of irrigameter device (KI) and to assess its performance in the irrigation of sunflower. The experiment was conducted in the Jaíba Irrigated Perimeter, Jaíba, MG, located at 15° 36' S and 43° 42' W, with an altitude of 460 m. For the evaluation of the performance of the irrigameter, the water level in the evaporimeter was kept at 1, 2, 3, 4, 5 and 6 cm high, and the evapotranspiration estimated by the irrigameter was compared to the reference evapotranspiration, calculated by the standard method Penman-Monteith FAO 56 (Allen et al., 1998). It was concluded that the values of KI obtained were 0.42, 0.69, 0.85, 1.07, 1.34 and 1.61 for the water levels in the evaporimeter corresponding to 1, 2, 3, 4, 5 and 6 cm, respectively. There was no significant difference between the yield of sunflower crop irrigated during day or night time; higher average values then reported by the literature were found. The irrigameter device was found to be satisfactory for irrigation control. To estimate the reference evapotranspiration in similar regions with similar climatic conditions, it is recommended to use the unit with evaporimeter adjusted to the level 3.7 cm.Keywords: irrigated agriculture, productivity of sunflower, irrigation efficiency.OLIVEIRA, E. M.; OLIVEIRA, R. A.; PAULA, A. L. T.; BAPTESTINI, J. C. M.; CAIXETA, S. P.; GIOVANELLI, L. B. Desempenho do irrigâmetro no manejo da irrigação no Perímetro Irrigado do Jaíba, MG, Brasil.

Reference evapotranspiration estimation by the Irrigameter in Southern Tocantins State, Brazil

“…Oliveira et al (2011a) elucidated that, to obtain the estimate of reference evapotranspiration under the climatic conditions of Jaíba-MG, it is recommended to use the device equipped with evaporator operating with water height of 3.7 cm.…”

“…According to Tagliaferre et al (2014;2015), the Irrigameter invented (its patent is filed in the National Institute of Industrial Property -INPI -under the number PI0502488-9) and developed at the Federal University of Viçosa (UFV) is an evapo-pluviometric device to be used in irrigation management, to optimize water use in irrigated agriculture, which can be used to estimate the reference evapotranspiration (Tagliaferre et al, 2012b;Oliveira et al, 2008;2011a;.…”

Irrigameter Use for Estimating Crop Evapotranspiration in Protected Environment

“…Depending on the various methods available for the estimation of evapotranspiration, choosing the most appropriate depends on the availability of meteorological data, the level of precision required, the purpose and cost of equipment acquisition (OLIVEIRA et al, 2011a). This has led researchers to develop simpler alternative methods to determine evapotranspiration for irrigation management, with the goal of reducing costs, ease of handling, scientific accuracy and consistency.…”