ESTUDO COMPARATIVO ENTRE METODOLOGIAS DE ESTIMATIVA DA EVAPOTRANSPIRAÇÃO DE REFERÊNCIA PARA LOCALIDADES DO NORTE DE MINAS GERAIS

ESTUDO COMPARATIVO ENTRE METODOLOGIAS DE ESTIMATIVA DA EVAPOTRANSPIRAÇÃO DE REFERÊNCIA PARA LOCALIDADES DO NORTE DE MINAS GERAIS LUCAS DA COSTA SANTOS1; LUCAS SANTOS DO PATROCÍNIO FIGUEIRÓ1; ALEX XAVIER RIBEIRO DE ANDRADE1; ANTÔNIO COSTA FERREIRA NETO1 E CAROLINE SALEZZI BONFÁ1 1 Departamento de Agronomia, Universidade Federal dos Vales do Jequitinhonha e Mucuri – UFVJM, Campus JK, Rodovia MGT 367-KM 583, nº 5000, Alto da Jacuba. CEP: 39.100-000, Diamantina, Minas Gerais, Brasil. E-mail: [email protected];[email protected];[email protected]; [email protected]; [email protected]. 1 RESUMO A determinação da evapotranspiração é imprescindível para a prática racional da irrigação, o que tem conduzido à formulação de diversas equações para estimativa desta importante variável meteorológica. Nesse sentido, faz-se necessário estudos comparativos com estas equações de modo a avaliar, localmente, sua aplicabilidade. Em linha com o exposto, objetivou-se comparar, para as condições climáticas de Salinas e Januária (ambos situados no Norte de Minas Gerais, Brasil), métodos empíricos de estimativa da evapotranspiração com o método padrão de Penman-Monteith (FAO56). Para tanto, utilizou-se dados meteorológicos de cinco anos (2016 a 2020) obtidos do Instituto Nacional de Meteorologia (INMET). Para a análise comparativa foram utilizados os seguintes indicadores estatísticos: coeficientes de determinação (R²) e correlação (r), erro absoluto médio (EAM), raiz do erro quadrado médio (REQM), índice de concordância (d) e índice de desempenho (c). Os resultados obtidos demonstram que, para as duas localidades avaliadas, o método de Blaney-Criddle apresenta o melhor desempenho para a estimativa da evapotranspiração, por outro lado, as equações de Hargreaves-Samani e Priestley-Taylor exibiram performance insatisfatória. Palavras-chave: métodos empíricos, demanda hídrica de cultivos, manejo da irrigação. SANTOS, L. C.; FIGUEIRÓ, L. S. P.; ANDRADE, A. X. R.; FERREIRA NETO, A. C.; BONFÁ, C. B. COMPARATIVE STUDY BETWEEN REFERENCE EVAPOTRANSPIRATION ESTIMATION METHODOLOGIES FOR NORTHERN MINAS GERAIS LOCATIONS 2 ABSTRACT The determination of evapotranspiration is essential for the rational practice of irrigation, which has led to the formulation of several equations to estimate this important meteorological variable. In line with the above objective was to compare, for the climatic conditions of Salinas and Januária (both located in the North of Minas Gerais, Brazil), empirical methods for estimating evapotranspiration with the standard method of Penman-Monteith (FAO56). For this purpose, meteorological data for five years (2016 to 2020) obtained from the National Institute of Meteorology (INMET) were used. For the comparative analysis, the following statistical indicators were used: coefficients of determination (R²) and correlation (r), mean absolute error (EAM), root mean square error (REQM), agreement index (d) and performance index (c). The results obtained demonstrate that, for the two locations evaluated, the Blaney-Criddle method presents the best performance for estimating evapotranspiration, on the other hand, the Hargreaves-Samani and Priestley-Taylor equations showed unsatisfactory performance. Keywords: crop water demand, empirical methods, irrigation management.

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Evaluation of empirical methods to estimate reference evapotranspiration in Uberaba, State of Minas Gerais, Brazil

Engenharia Agrícola ◽

10.1590/s0100-69162012000500007 ◽

2012 ◽

Vol 32 (5) ◽

pp. 875-888 ◽

Cited By ~ 4

Author(s):

Giovani L. de Melo ◽

André L. T. Fernandes

Keyword(s):

Standard Method ◽

Reference Evapotranspiration ◽

Potential Evapotranspiration ◽

Minas Gerais ◽

Climatic Conditions ◽

Empirical Methods ◽

Monthly Data ◽

And Performance ◽

Simple Statistical Analysis ◽

Climatic Elements

Evapotranspiration is the process of water loss of vegetated soil due to evaporation and transpiration, and it may be estimated by various empirical methods. This study had the objective to carry out the evaluation of the performance of the following methods: Blaney-Criddle, Jensen-Haise, Linacre, Solar Radiation, Hargreaves-Samani, Makkink, Thornthwaite, Camargo, Priestley-Taylor and Original Penman in the estimation of the potential evapotranspiration when compared to the Penman-Monteith standard method (FAO56) to the climatic conditions of Uberaba, state of Minas Gerais, Brazil. A set of 21 years monthly data (1990 to 2010) was used, working with the climatic elements: temperature, relative humidity, wind speed and insolation. The empirical methods to estimate reference evapotranspiration were compared with the standard method using linear regression, simple statistical analysis, Willmott agreement index (d) and performance index (c). The methods Makkink and Camargo showed the best performance, with "c" values of 0.75 and 0.66, respectively. The Hargreaves-Samani method presented a better linear relation with the standard method, with a correlation coefficient (r) of 0.88.

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Empirical methods for reference evapotranspiration estimation

Scientia Agraria Paranaensis ◽

10.18188/sap.v19i3.21487 ◽

2020 ◽

Vol 19 (3) ◽

pp. 203-210

Author(s):

Oswaldo Palma Lopes Sobrinho ◽

Wady Lima Castro Júnior ◽

Leonardo Nazário Silva dos Santos ◽

Gerlange Soares da Silva ◽

Álvaro Itaúna Schalcher Pereira ◽

...

Keyword(s):

Reference Evapotranspiration ◽

Meteorological Data ◽

Physical Phenomenon ◽

Climatic Conditions ◽

Alternative Methods ◽

Empirical Methods ◽

Class A ◽

Evapotranspiration Estimation ◽

Almost All ◽

Meteorological Elements

The reference evapotranspiration (ETo) is a parameter applied in meteorological, climatological and hydrological studies being of great importance for the planning, management and management of water resources. Due to the need for knowledge about the loss of water from vegetated surfaces, researchers have developed a variety of methods for estimating ETo, some of which are well accepted, while others are criticized, such as the Penman-Monteith-FAO (PM-FAO) meteorological data, which is not always available by limiting its use. The PM-FAO method has been used for decades to be considered internationally and most appropriate for ETo estimates. This method represents the physical phenomenon of evapotranspiration that involves almost all meteorological elements analyzed in automatic and conventional meteorological stations. On the other hand, when this method is impossible to apply due to the lack of some input data, alternative methods are justified (Hargreaves-Samani, Blaney-Criddle, Priestley-Taylor, Jensen-Haise, Camargo, Makkink, Kharrufa , Linacre, Class A tank, Thornthwaite and solar radiation) according to soil and climatic conditions.

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COMPARAÇÃO DE MÉTODOS DE ESTIMATIVA DE ETO E ANÁLISE DE SENSIBILIDADE PARA DIFERENTES CLIMAS BRASILEIROS

Irriga ◽

10.15809/irriga.2019v24n3p538-551 ◽

2019 ◽

Vol 24 (3) ◽

pp. 538-551

Author(s):

João Guilherme Araújo Lima ◽

Paula Carneiro Viana ◽

José Espínola Sobrinho ◽

João Paulo Chaves Couto

Keyword(s):

Sensitivity Analysis ◽

Mean Absolute Error ◽

Irrigation Management ◽

Global Radiation ◽

Absolute Error ◽

Climatic Conditions ◽

Estimation Methods ◽

Coefficient Of Determination ◽

The One ◽

E Mail

COMPARAÇÃO DE MÉTODOS DE ESTIMATIVA DE ETO E ANÁLISE DE SENSIBILIDADE PARA DIFERENTES CLIMAS BRASILEIROS JOÃO GUILHERME ARAÚJO LIMA1; PAULA CARNEIRO VIANA1; JOSÉ ESPÍNOLA SOBRINHO2 E JOÃO PAULO CHAVES COUTO3 1Departamento de Engenharia Civil, UNINASSAU, BR 104, KM 68, N° 1215, Agamenon Magalhães, 55000-000, Caruaru, Pernambuco, Brasil. [email protected]; [email protected]; 2Departamento de Ciências Ambientais e Tecnológicas, UFERSA, Rua Francisco Mota, N° 572, Presidente Costa e Silva, 59625-900 Mossoró, Rio Grande do Norte, Brasil. [email protected]; 3Programa de Pós-Graduação em Engenharia Agrícola, Núcleo de Engenharia de Água e Solo, UFRB, Rua Rui Barbosa, N° 710, Centro, 44380-000, Cruz das Almas, Bahia, Brasil. E-mail: [email protected]. 1 RESUMO A estimativa da evapotranspiração de referência (ETo) tem grande importância para a agricultura e manejo da irrigação. O método Penman-Monteith é considerado padrão para estimativa da ETo. No entanto, por ser completo, o método padrão apresenta como desvantagem a necessidade de uma gama de variáveis meteorológicas. O objetivo dessa pesquisa foi, em escala diária, avaliar o desempenho dos métodos de Hargreaves-Samani, Makkink, Priestley-Taylor, Turc, Radiação FAO-24 e Blaney-Criddle, para as condições climáticas das seis regiões do Brasil. A verificação do desempenho desses modelos foi por meio da comparação ao método de Penman-Monteith. Para avaliar o desempenho dos métodos foi utilizada a raiz quadrada do quadrado médio do erro (RQME), erro absoluto médio (EAM), erro de estimativa (PE) e coeficiente de determinação (R2). Entre os métodos estudados, o de Turc foi o que apresentou melhores resultados para todos os climas do Brasil, exceto para o clima Tropical litorâneo. O método de Makkink foi o que apresentou melhor resultado para o clima Tropical litorâneo. A análise de sensibilidade revelou que a temperatura do ar e a radiação global são as variáveis mais importantes para o método do método Penman-Monteith, exceto para o município BL, em que a variável umidade relativa do ar foi a mais importante. Palavras-Chave: irrigação, consumo de água, evapotranspiração. LIMA, J. G. A.; VIANA, P. C.; SOBRINHO, J. E.; COUTO, J. P. C. COMPARISON OF ETO ESTIMATION METHODS AND SENSITIVITY ANALYSIS FOR DIFFERENT BRAZILIAN CLIMATES 2 ABSTRACT Estimation of reference evapotranspiration (ETo) is of great importance for agriculture and irrigation management. The Penman-Monteith method is considered standard for estimating ETo. However, because it is complete, the standard method presents as a disadvantage the need for a range of meteorological variables. The objective of this research was to evaluate the performance of Hargreaves-Samani, Makkink, Priestley-Taylor, Turc, FAO-24 and Blaney-Criddle methods for the climatic conditions of the six Brazilian regions. The verification of the performance of these models was made by comparison to the Penman-Monteith method. To evaluate the performance of the methods, the square root of mean-square error (MSE), mean absolute error (MAE), error of estimate (EE) and coefficient of determination (R2) were used. Among the methods studied, that of Turc was the one that presented the best results for all the climates of Brazil, except for the tropical coastal climate. The Makkink method was the one that presented the best result for the coastal tropical climate. Sensitivity analysis revealed that air temperature and global radiation are the most important variables for the Penman-Monteith method, except for BL municipality, where the variable relative humidity was the most important. Keywords: irrigation, water consumption, evapotranspiration.

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Comparison between forecasts of reference evapotranspiration and ETo values calculated using data from different climatic conditions

10.5194/egusphere-egu2020-372 ◽

2020 ◽

Author(s):

Ghaieth Ben Hamouda ◽

Francesca Ventura ◽

Daniele Zaccaria ◽

Khaled M. Bali ◽

Richard L. Snyder

Keyword(s):

Reference Evapotranspiration ◽

Irrigation Management ◽

Climatic Conditions ◽

Physical Models ◽

Dew Point ◽

Water Losses ◽

Plant Canopies ◽

Crucial Component ◽

And Performance ◽

Using Data

<p>Evapotranspiration is the transfer of water from the earth's surface to the atmosphere. It comprises the sum of water losses to atmosphere due to the processes of evaporation of moisture from soil, water bodies and wet plant canopies, and the transpiration of water from plants. Forecasts of this crucial component of the hydrologic cycle can be very valuable for growers, farm managers, irrigation practitioners, water resource planners and managers, and reservoir operators for their planning, allocation, delivery and scheduling decisions, as well as to hydrologic scientists for research purposes. Verifying the reliability of models&#8217; forecasts is among the critical tasks for development and performance evaluation of physical models. In fact, the verification allows understanding the models&#8217; behavior, and evaluating their applicability and dependability. The US National Weather Service (NWS) has released a product that provides forecasts of reference evapotranspiration (FRET) at 2.5-km grid resolution for the entire continental US. In this study, a comparison is made between ETo estimates from FRET and ETo values calculated by the California Irrigation Management Information System (CIMIS) for 68 days during summer 2019. Both the FRET forecasts and ETo values were obtained from NWS and CIMIS, respectively, on the basis of 15 CIMIS locations that are representative of different climatic conditions in California. In addition, air temperature, dew point temperature, relative humidity, wind speed, and vapor pressure deficit (VPD) data were also collected/calculated from the NWS and CIMIS websites to analyze the sensitivity of FRET forecasts to predictions of these parameters. All FRET forecasts were performed with timescales of 1, 3, 5 and 7 days. Statistical indices were calculated to assess the dependability of FRET values. They showed a good correlation of the FRET model outputs with CIMIS ETo data, with some differences depending on the climatic characteristics of selected weather stations&#8217; locations, suggesting that FRET data could be valuable for anticipating near-future water demand and improve irrigation management in California.</p>

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MÉTODOS DE ESTIMATIVA DA EVAPOTRANSPIRAÇÃO DE REFERÊNCIA (ET0) NO MUNICÍPIO DE SANTA TERESA, ES

Irriga ◽

10.15809/irriga.2017v22n4p701-714 ◽

2017 ◽

Vol 22 (4) ◽

pp. 701-714

Author(s):

Andre Dalla Bernardina Garcia ◽

José Carlos Mendonça ◽

Claudio De Almeida Martins

Keyword(s):

Water Resources ◽

Solar Radiation ◽

Reference Evapotranspiration ◽

Irrigation Management ◽

Absolute Error ◽

Estimation Methods ◽

Coefficient Of Determination ◽

Espírito Santo ◽

Espirito Santo ◽

E Mail

MÉTODOS DE ESTIMATIVA DA EVAPOTRANSPIRAÇÃO DE REFERÊNCIA (ET0) NO MUNICÍPIO DE SANTA TERESA, ES ANDRE DALLA BERNARDINA GARCIA1; JOSÉ CARLOS MENDONÇA2 E CLAUDIO MARTINS DE ALMEIDA3 1Instituto Federal do Espírito Santo, Rodovia ES 080, Km 93, São João de Petrópolis, CEP 29660-000, Santa Teresa, ES, Fone:(27)3259-7878, E-mail:[email protected]ório de Engenharia Agrícola/UENF, Av. Alberto Lamego, 2000,P1,sl 209, Horto, Campos dos Goytacazes, RJ, Fone (22) 2739-7308, E-mail: [email protected]ório de Engenharia Agrícola/UENF, Av. Alberto Lamego, 2000,P1,sl 209, Horto, Campos dos Goytacazes, RJ, Fone (22) 2739-7308, E-mail: [email protected] 1 RESUMO Devido aos constantes debates ocorridos sobre a racionalização dos recursos hídricos, a busca de maneiras e boas práticas de utilização da água têm sido cada vez mais difundidas, principalmente na agricultura. Dentre os meios de preservar os recursos hídricos está o manejo de irrigação, por isso é muito importante realizar a estimativa da evapotranspiração de referência (ET0). Neste contexto, o presente trabalho foi desenvolvido para o município de Santa Teresa, localizado na meso região Central Espírito-Santense com o objetivo de avaliar e comparar diferentes métodos de estimativa da ET0 com o método de Penman-Monteith FAO56, considerado como padrão de calibração, na ausência de dados lisimétricos. Os métodos utilizados foram os de Hargreaves-Samani, Radiação Solar, Makkink, Jesen-Haise, Linacre e Penman Simplificado. O coeficiente de determinação (R2), índice de concordância de Willmott (D), o erro médio absoluto (MAE), o erro máximo (EMAX), a eficiência do método (EF) e o índice de desempenho (c) foram utilizados para avaliar os indicadores observados. Dentre os métodos avaliados, os que apresentaram melhores resultados foram os de Makkink e Penman Simplificado (R2 = 0,96 e 0,96; D= 0,99 e 0,97; MAE = 0,23 e 0,44; EMAX = 1,36 e 1,07; EF = 0,95 e 0,87 e c = 0,97 e 0,95) respectivamente, seguidos do método de Hargreaves-Samani (R2 = 0,86; D= 0,91; MAE = 0,60; EMAX = 2,16; EF = 0,69 e c = 0,85). Os resultados obtidos com os métodos de Linacre, Radiação Solar e Jensen-Haise foram inferiores e sendo a sua utilização não recomendada para a região de Santa Teresa, ES. Palavras-chave: Agrometeorologia, demanda hídrica, irrigação, Penman-Monteith GARCIA, A. D. B.; MENDONÇA, J. C.; MARTINS, C. A.METHODS FOR ESTIMATING REFERENCE EVAPOTRANSPIRATION (ET0) FOR THE CITY OF SANTA TERESA, ES 2 ABSTRACT Due to constant discussion about rationalization of water resources, the search for ways and good practices in water use have been increasingly widespread, especially in agriculture. Among the means of preserving water resources is irrigation management, so it is very important to estimate the reference evapotranspiration (ET0). In this context, the present work was developed for the municipality of Santa Teresa, located in Central Espírito-Santo mesoregion with the objective of evaluating and comparing different ET0 estimation methods with Penman-Monteith FAO56 method considered as calibration standard, in the absence of lysimetric data. The methods used were those of Hargreaves-Samani, Solar Radiation, Makkink, Jesen-Haise, Linacre and Penman Simplified. The coefficient of determination (R2), Willmott concordance index (D), mean absolute error (MAE), maximum error (EMAX), method efficiency (EF) and performance index (c) were used for assessing the observed indicators. Among the evaluated methods, the ones with the best results were Makkink and Penman Simplified (R² = 0.96 and 0.96 D = 0.99 and 0.97, MAE = 0.23 and 0.44, EMAX = 1.36 and 1.07, EF = .95 and 0.87 and c = 0.97 and 0.95) respectively, followed by Hargreaves-Samani methods (R² = 0.86, D = 0.91, MAE = 0.60, EMAX = 2.16, EF = 0.69 and c = 0.85). The results obtained with the methods of Linacre, Solar Radiation and Jensen-Haise were lower and their use is not recommended for the region of Santa Teresa, ES. Keywords: Agrometeorology, hydric demand, irrigation, Penman-Montheith

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EVAPOTRANSPIRAÇÃO E COEFICIENTE DE CULTURA DO CAFEEIRO IRRIGADO A PARTIR DE IMAGENS DE SENSORES ORBITAIS

Irriga ◽

10.15809/irriga.2019v1n1p31-37 ◽

2019 ◽

Vol 1 (1) ◽

pp. 31-37

Author(s):

THALLES LOIOLA DIAS ◽

Alex PORTO RODRIGUES ◽

MILLER RAIK ARCANJO BATISTA ◽

Marcelo Rossi Vicente ◽

RONALDO MEDEIROS DOS SANTOS

Keyword(s):

Energy Balance ◽

Surface Energy ◽

Surface Energy Balance ◽

Irrigation Management ◽

Crop Coefficient ◽

Minas Gerais ◽

Crop Evapotranspiration ◽

Landsat 7 ◽

Sebal Model ◽

E Mail

EVAPOTRANSPIRAÇÃO E COEFICIENTE DE CULTURA DO CAFEEIRO IRRIGADO A PARTIR DE IMAGENS DE SENSORES ORBITAIS THALLES LOIOLA DIAS1; ALEX PORTO RODRIGUES2; MILLER RAIK ARCANJO BATISTA3; Marcelo Rossi Vicente4 e Ronaldo Medeiros dos Santos5 1 Instituto Federal do Norte de Minas Gerais, Campus Salinas, Fazenda Varginha Km 02 Rod. Salinas/Taiobeiras - Salinas/MG -CEP:39560-000, Salinas, MG, Brasil. E-mail: [email protected]. 2 Instituto Federal do Norte de Minas Gerais, Campus Salinas, Fazenda Varginha Km 02 Rod. Salinas/Taiobeiras - Salinas/MG -CEP:39560-000, Salinas, MG, Brasil. E-mail: [email protected]. 3 Instituto Federal do Norte de Minas Gerais, Campus Salinas, Fazenda Varginha Km 02 Rod. Salinas/Taiobeiras - Salinas/MG -CEP:39560-000, Salinas, MG, Brasil. E-mail: [email protected]. 4 Instituto Federal do Norte de Minas Gerais, Campus Salinas, Fazenda Varginha Km 02 Rod. Salinas/Taiobeiras - Salinas/MG -CEP:39560-000, Salinas, MG, Brasil. E-mail: [email protected]. 5 Instituto Federal do Norte de Minas Gerais, Campus Salinas, Fazenda Varginha Km 02 Rod. Salinas/Taiobeiras - Salinas/MG - CEP:39560-000, Salinas, MG, Brasil. E-mail:[email protected]. 1 RESUMO O uso de sensoriamento remoto na agricultura é uma realidade. Dentre os diversos usos, destaca-se a determinação da evapotranspiração dos cultivos para o auxílio do processo de gerenciamento da irrigação. O presente trabalho objetivou determinar a evapotranspiração e o coeficiente da cultura do cafeeiro através do algoritmo SEBAL (Surface Energy Balance Algorithm for Land) na região Oeste da Bahia. Para a realização do estudo foram utilizadas imagens do satélite LANDSAT 7. A evapotranspiração de referência foi estimada pelo método Penman-Monteith FAO e, posteriormente, calculou-se o coeficiente da cultura (Kc) com base na evapotranspiração obtida via SEBAL. Os índices estatísticos para avaliar a eficácia do modelo SEBAL foram: o desvio da raiz quadrada média (RMSE); o erro médio absoluto (MAE); o coeficiente de determinação (R2); e o erro relativo (RE). O modelo SEBAL mostrou-se eficiente na determinação da evapotranspiração da cultura do cafeeiro e no coeficiente de cultura. Palavras-chave: índice de vegetação; sebal; manejo de irrigação. DIAS, T.L.; RODRIGUES, A.P.; BATISTA, M.R.A.; VICENTE, M.R.; SANTOS, R. M. EVAPOTRANSPIRATION AND CROP COEFFICIENT OF COFFEE PLANTS FROM ORBITAL SENSORS IMAGES 2 ABSTRACT The use of remote sensing in agriculture is a reality. Among the various uses, the determination of crop evapotranspiration to aid the irrigation management process is detached. The present work aimed to determine the evapotranspiration and the crop coefficient of coffee through the Surface Energy Balance Algorithm for Land (SEBAL) in western Bahia. LANDSAT 7 satellite images were used to perform the study. The reference evapotranspiration was estimated by the FAO Penman-Monteith method and subsequently the crop coefficient (Kc) was calculated based on the evapotranspiration obtained by SEBAL. The statistical indexes for evaluating the effectiveness of the SEBAL model were the root mean square error (RMSE), the mean absolute error (MAE), the coefficient of determination (R²) and the relative error (RE). The SEBAL model proved to be efficient in determining coffee crop evapotranspiration and crop coefficient. Keywords: vegetation index; sebal; water management.

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

Revista Brasileira de Engenharia Agrícola e Ambiental ◽

10.1590/1807-1929/agriambi.v21n5p293-297 ◽

2017 ◽

Vol 21 (5) ◽

pp. 293-297

Author(s):

Luan B. Giovanelli ◽

Rubens A. Oliveira ◽

Jair C. Oliveira-Filho ◽

Júlio C. M. Baptestini ◽

Fábio T. Delazari ◽

...

Keyword(s):

Energy Consumption ◽

Experimental Design ◽

Crop Yield ◽

Water Depth ◽

Reference Evapotranspiration ◽

Meteorological Data ◽

Climatic Conditions ◽

Equipment Acquisition ◽

Evapotranspiration Estimation ◽

Water Height

ABSTRACT The choice for the most appropriate method to estimate evapotranspiration depends on the availability of meteorological data, required level of precision and cost of equipment acquisition. For this estimate, the Irrigameter is simple to operate, precise and economically viable to farmers. In addition, it collaborates in the application of the necessary water depth to crops, thus avoiding unnecessary energy consumption, environmental degradation, and increasing crop yield and improving crop quality. In this context, the objective of this research was to estimate the reference evapotranspiration using the Irrigameter, for the climatic conditions of the Southern Tocantins state, Brazil. The experimental design was completely randomized with Irrigameters operating with seven water heights in the evaporator, as treatments, with three replicates. The reference evapotranspiration was obtained by FAO-56 Penman-Monteith method. For the analyzed climatic conditions, the water height in the evaporator recommended to estimate the reference evaporation in the spring is 3.4 cm; summer, 4.0 cm; fall, 3.8 cm; and winter, 2.3 cm.

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YIELD OF CHICKPEAS SOWN AT DIFFERENT TIMES

Revista Caatinga ◽

10.1590/1983-21252018v31n412rc ◽

2018 ◽

Vol 31 (4) ◽

pp. 900-906 ◽

Cited By ~ 1

Author(s):

RAMON IVO SOARES AVELAR ◽

CÂNDIDO ALVES DA COSTA ◽

FERNANDO DA SILVA ROCHA ◽

NELSON LICÍNIO CAMPOS DE OLIVEIRA ◽

WARLEY MARCOS NASCIMENTO

Keyword(s):

Block Design ◽

Minas Gerais ◽

Climatic Conditions ◽

Joint Analysis ◽

The North ◽

Randomized Block Design ◽

Sowing Dates ◽

Productive Potential ◽

Maximum Temperatures ◽

Sowing Season

ABSTRACT In Brazil, studies on chickpeas (Cicer arietinum L.) have demonstrated the high productive potential of this crop, especially in the Cerrado areas of Cristalina, GO, and Brasília, DF. Due to dry winter climatic conditions, the North of Minas Gerais may be very suitable for the production of this crop. However, more information on chickpea sowing dates is needed. Therefore, the objective of the present study was to evaluate different chickpea sowing times in two municipalities of Minas Gerais State in Brazil: Montes Claros and Januária. The experiment was carried out in a randomized block design, comprising three sowing dates (12 May, 23 June, and 22 July, 2015), and seven replications. The cultivar used was BRS Aleppo, and the chickpeas were harvested 121 days after sowing. The variables evaluated included plant height, productivity, number of pods with one grain, and number of pods with two grains. The data were submitted to analysis of variance, and joint analysis of the experiments was performed. The highest yields were obtained when chickpeas were sown in May in Montes Claros, with a yield of 5.3 t ha-1. In Januária, chickpeas sown in May and June produced yields greater than 3.0 t ha-1. The plants sown in July, considered late for planting, were harvested during the rainy season, which compromised the quality and yield of the grains. In addition, maximum temperatures above 30ºC were recorded from September onwards in both locations, which also resulted in a reduction in the number of grains per plant. Thus, this sowing season is not recommended in the studied region.

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Crop evapotranspiration estimation using remote sensing and the existing network of meteorological stations in Cyprus

Advances in Geosciences ◽

10.5194/adgeo-30-39-2011 ◽

2011 ◽

Vol 30 ◽

pp. 39-44 ◽

Cited By ~ 4

Author(s):

G. Papadavid ◽

D. Hadjimitsis ◽

S. Michaelides ◽

A. Nisantzi

Keyword(s):

Satellite Data ◽

Meteorological Data ◽

Irrigation Management ◽

Reference Method ◽

Geographical Information ◽

Crop Evapotranspiration ◽

Remotely Sensed Data ◽

Water Losses ◽

Evapotranspiration Estimation ◽

Agricultural Areas

Abstract. Cyprus is frequently confronted with severe droughts and the need for accurate and systematic data on crop evapotranspiration (ETc) is essential for decision making, regarding water irrigation management and scheduling. The aim of this paper is to highlight how data from meteorological stations in Cyprus can be used for monitoring and determining the country's irrigation demands. This paper shows how daily ETc can be estimated using FAO Penman-Monteith method adapted to satellite data and auxiliary meteorological parameters. This method is widely used in many countries for estimating crop evapotranspiration using auxiliary meteorological data (maximum and minimum temperatures, relative humidity, wind speed) as inputs. Two case studies were selected in order to determine evapotranspiration using meteorological and low resolution satellite data (MODIS – TERRA) and to compare it with the results of the reference method (FAO-56) which estimates the reference evapotranspiration (ETo) by using only meteorological data. The first approach corresponds to the FAO Penman-Monteith method adapted for using both meteorological and remotely sensed data. Furthermore, main automatic meteorological stations in Cyprus were mapped using Geographical Information System (GIS). All the agricultural areas of the island were categorized according to the nearest meteorological station which is considered as "representative" of the area. Thiessen polygons methodology was used for this purpose. The intended goal was to illustrate what can happen to a crop, in terms of water requirements, if meteorological data are retrieved from other than the representative stations. The use of inaccurate data can result in low yields or excessive irrigation which both lead to profit reduction. The results have shown that if inappropriate meteorological data are utilized, then deviations from correct ETc might be obtained, leading to water losses or crop water stress.

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Ecological and geographical grouping of pear varieties and identification of new sources for breeding in the conditions of the North Caucasus

New Technologies ◽

10.47370/2072-0920-2020-16-6-48-57 ◽

2021 ◽

Vol 16 (6) ◽

pp. 48-57

Author(s):

I. A. Bandurko ◽

Z. Sh. Daguzhieva

Keyword(s):

Meteorological Data ◽

Plant Genetic Resources ◽

Climatic Conditions ◽

Biological Traits ◽

North Caucasus ◽

Early Maturity ◽

The North ◽

Long Term Study ◽

World Collection ◽

The World

The article presents the results of a long-term study of the world collection of pears, which is one of the largest in the RIPB system. It is kept at the Maykop Experimental Station of the Federal Research Center of the All-Russian Institute of Plant Genetic Resources named after N.I. Vavilov» branch and has 875 varieties, 248 species, forms and varieties, and is constantly updated with new samples. The collection includes wild species, as well as Russian and foreign varieties from Europe, America, Asia. The research was carried out in the soil and climatic conditions of the foothill zone of the North Caucasus in 2005–2015. The aim of the research is to study the dependence of biological traits and properties on the origin of samples and to isolate genotypes with the maximum expression of traits for use in breeding. In the research the methodological instructions of the All-Russian Research Institute of Breeding of Fruit Crops and the North Caucasus Center for the Breeding of Fruit, Berry, Flower and Ornamental Crops and Grapes have been used. The analysis of weather conditions has been carried out using meteorological data of the MES of the RIPB Branch. The regularities of the manifestation of signs and biological properties of the studied samples depending on their geographical origin have been established. The varieties that combine a fairly good quality of fruits and other, valuable characteristics have been identified: late flowering for protection from frost – Obilnaya Tuza, Uspenka; resistance to fungal diseases – Vodnik, Utrennyaya Svezhest; early maturity – Borup, Napoca and high regular yield – P. regelii x P. pyrifolia № 2 interspecific hybrid. As a result of many years of studying the world collection of pears the list of isolated genotypes of valuable traits has been added, the use of which contributes to a significant increase in the efficiency of breeding work.

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