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| Cunha,Fernando F. da; Souza,Ivan P. de; Campos,Washington de O.; Andrade Júnior,Valter C. de; Magalhães,Thiago A.. |
| ABSTRACT In radish production, the choice of proper genotypes and irrigation regime is of great importance to achieve success. In light of this, the current study aimed to evaluate the agronomic performance of a few radish genotypes under different irrigation strategies. The plants were grown in the city of Unaí - MG, in Brazil, under field conditions, and during two cycles, one of 40 days (from February 28 to April 8, 2015) and other of 51 days (from May 9 to June 28, 2015). The experimental design was a randomized block design in a split-plot arrangement with four replications. The treatments consisted of four irrigation strategies (50, 75, 100, and 125% of crop evapotranspiration - ETc) applied by a dripping irrigation system, while subplots consisted... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Horticulture; Irrigation management; Raphanus sativus. |
| Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162019000200182 |
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| Oliveira,Job T. de; Oliveira,Rubens A. de; Cunha,Fernando F. da; Santos,Eduardo S. dos. |
| ABSTRACT Studies that seek to identify a smaller number of soil attributes that represent others can generate less expenditure of time and financial resources for monitoring cultivated areas. Thus, this study aimed to analyze the spatial distribution and spatial autocorrelation of physical attributes of an Oxisol (Latossolo Vermelho Amarelo, Brazilian Soil Classification System). The evaluated attributes consisted of soil density (SD), total porosity (TP), free porosity (FP), field capacity (FC), permanent wilt point (PW), and total water availability (TW). Semivariogram adjustments and semivariance estimates were performed to characterize the structure and magnitude of the spatial dependence of soil attributes. The attributes were distributed on thematic... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Precision agriculture; Spatial dependence; Geostatistics; Moran index. |
| Ano: 2021 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162021000200255 |
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| Cunha,Fernando F. da; Magalhães,Fernando F.; Castro,Marco A. de; Souza,Epitácio J. de. |
| ABSTRACT Before choosing the method of the estimate of reference evapotranspiraton (ET0) in a region, it is important to evaluate the degree of precision of the model. The present research aimed to evaluate the performance of 30 methods for daily ET0 estimate in the Cassilândia city, Brazil. The meteorological data had been obtained from the National Institute of Meteorology in the period of four years (from April, 2008 to March, 2012). As standard method it was chosen the Penman-Monteith-FAO56, and the comparison of the results was by means of the estimated standard error (ESE), the determination coefficient (R2), the coefficients “a” and “b” of the linear regressions, Willmott's index of agreement (d), Pearson's correlation coefficient (r) and the... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Agrometeorology; ET0; Evaporation; Irrigation; Penman-Monteith-FAO 56 method. |
| Ano: 2017 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162017000100173 |
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| Filgueiras,Roberto; Mantovani,Everardo C.; Althoff,Daniel; Dias,Santos H. B.; Cunha,Fernando F. da. |
| ABSTRACT Surface temperature (Ts) is a determining factor to obtain energy balance parameters, being relevant to understand the influence of this variable on the estimation of evapotranspiration. Thus, the objective of this study was to simulate errors in Ts estimation to verify the consequences of actual evapotranspiration (ETa) estimated by the SAFER (Simple Algorithm for Evapotranspiration Retrieving) model. For this, an image of the Landsat-8 satellite was used to induce errors from 0.2K to 10K in the variable Ts, allowing verifying the consequences in the ETa data. After the estimations of Ts and ETa, the quantitative consequences and dynamics of Ts impact on the ETa data were verified along the different land uses in the study area. The results... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Energy balance; Irrigated areas; Remote sensing; NDVI. |
| Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162019000800023 |
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| Filgueiras,Roberto; Oliveira,Vinicius M. R. de; Cunha,Fernando F. da; Mantovani,Everardo C.. |
| ABSTRACT One of the main factors that determine the success of decision-making in the fields is the climatic factor. This way, the geostatistical techniques have been used to represent and understand the spatial or temporal dynamics of meteorological parameters. Therefore, the aim of this research was to represent temporally through thematic maps, the average daily behavior for meteorological variables and the hydric balance for the municipality of Patos de Minas - MG. The climatic data were acquired from the automatic station INMET from the years 1990 to 2015. Later, it was calculated the evapotranspiration and the hydric balance for different capacities of available water in the soil (CAW): 24 mm, 48 mm, 80 mm and 112 mm. The climate variables showed... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Climate; Geostatistical; Ordinary kriging; Thematic maps. |
| Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162018000500705 |
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| Araújo,Edcássio D.; Santos,Dionei L.; Alvino,Francisco C. G.; Ferreira,Lucas B.; Cunha,Fernando F. da. |
| ABSTRACT Correct determinations of distribution (Ed) and application (EA) efficiencies allow adequate estimations of the gross irrigation depth. This study aimed: i) to determine the distribution efficiency using the Christiansen uniformity coefficient (CUC) in a sprinkler irrigation system under different weather conditions and working pressures; ii) to compare the mean, median, and cumulative CUC values; and iii) to evaluate the predictive capacity of four EA estimation models. CUC values were determined from 80 assessments, as well as the mean, median, and cumulative. The precipitated water depth accumulated in each collector was considered for the accumulated CUC. More uniform evaluations were used for EA (working pressure of 196 kPa), resulting in 20... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Uniformity coefficient; Irrigation efficiency; Evaporation and wind drift. |
| Ano: 2020 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162020000100024 |
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| Venancio,Luan P.; Cunha,Fernando F. da; Mantovani,Everardo C.; Sediyama,Gilberto C.; Eugenio,Fernando C.; Aleman,Catariny C.. |
| ABSTRACT The Penman-Monteith method (PM-FAO) is recommended as standard for calculation of reference evapotranspiration (ETo). However, its use requires a series of meteorological variables that is not normally available, restricting its application in many locations. A solution to the problem of unavailability of meteorological data was presented in FAO Bulletin 56, which contains methodologies for estimating wind speed, solar radiation and relative humidity. The objective of the present study was to evaluate the performance of the PM-FAO methodologies for missing data and Hargreaves-Samani as alternatives to the PM-FAO standard method at different time scales and seasons for the municipalities of Linhares and São Mateus, located in the northern region of... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Data scarcity; Time scale; Seasons. |
| Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662019000300153 |
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| Alencar,Carlos A. B. de; Oliveira,Rubens A. de; Cóser,Antônio C.; Martins,Carlos E.; Cunha,Fernando F. da; Figueiredo,José L. A.. |
| Objetivou-se, com o presente trabalho, avaliar a produtividade de matéria seca de seis gramíneas, sob efeito de diferentes lâminas de irrigação, em diferentes estações do ano. O experimento foi conduzido em esquema de parcelas subsubdivididas havendo, nas parcelas seis gramíneas (Xaraés, Mombaça, Tanzânia, Pioneiro, Marandu e Estrela), nas subparcelas, seis lâminas de irrigação (0, 18, 45, 77, 100 e 120% da referência) e, nas subsubparcelas, as estações (outono/inverno e primavera/verão) no delineamento inteiramente casualizado, com duas repetições. Para diferenciar a aplicação das lâminas de irrigação, utilizou-se o sistema por aspersão em linha. O efeito proporcionado pelas diferentes gramíneas na produtividade de matéria seca dependeu da lâmina de... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: B. brizantha; P. maximum; P. purpureum; C. nlemfuensis; Sistema em aspersão em linha. |
| Ano: 2009 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662009000600003 |
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