Gertrudes Macario de Oliveira

Influência da irrigação sobre o albedo

The influence of irrigation on the albedo of a peanut crop during its development cycle, and in particular on the day when irrigation took place, is analyzed in this study. The field research was conducted in the irrigated perimeter of the Experimental Station of CODEVASF, in the municipal district of Rodelas, BA, during the period of September to December of 1996. The results showed that the albedo suffered significant variations on the days of irrigation as well as on the day after irrigation. Under normal conditions, the albedo varied from a maximum of 29.8% in the initial phase of the experiment with the soil still uncovered, to a minimum of 18.6% at the end of the kernel development phase. However, on the days of irrigation, the albedo varied with the time of irrigation. The daily mean value of the albedo reduced by 6.4% when the irrigations took place in the early hours of the morning.

Avaliação do desempenho de diferentes métodos de estimativa da evaporação para duas regiões da Paraíba

As regioes do Cariri e Sertao da Paraiba, nas cidades de Boqueirao e Patos, no periodo de 1 de abril de 2002 a 28 de fevereiro de 2003, foram estudadas com o objetivo de se avaliar o desempenho de diferentes metodos e obter-se as melhores estimativas da evaporacao para essas regioes; para tanto, usaram-se medidas diarias de evaporacao do tanque evaporimetrico padrao de 20 m2 (WMO, 1996). Os metodos avaliados foram: Penman (1948); balanco de energia - razao de Bowen; Linacre (1993); Snyder (1992); Kohler et al. (1955); Gangopadhyaya et al. (1966) e Hounam (1973). Os resultados indicaram que os metodos de estimativa de evaporacao que utilizam a umidade relativa do ar, velocidade do vento e radiacao solar, apresentaram os melhores desempenhos. O metodo proposto por Snyder (1992) teve o melhor desempenho nas duas regioes estudadas, com erros relativos de -4,2% para Boqueirao e -3,3% para Patos. O metodo de Linacre (1993), que utiliza os valores extremos de temperatura diaria do ar, apesar de ter apresentado os maiores erros relativos -16,9% em Boqueirao e -18,2% em Patos, mostrou que, se for corretamente calibrado, pode ter desempenho satisfatorio para as duas areas estudadas.

ESTIMATIVAS DE EVAPOTRANSPIRAÇÃO E AS CONSEQÜÊNCIAS DEVIDO AOS ERROS NA DETERMINAÇÃO DE SALDO DE RADIAÇÃO E EFEITOS ADVECTIVOS

The objective of this study was to analyze the consequences in the evapotranspiration estimates (ET) during the growing cycle of a peanut crop due to the errors commited in the determination of the radiation balance (Rn), as well as those caused by the advective effects. This research was conducted at the Experimental Station of CODEVASF in an irrigated perimeter located in the city of Rodelas, BA, during the period of September to December of 1996. The results showed that errors of the order of 2.2 MJ m -2 d -1 in the calculation of Rn, and consequently in the estimate of ET, can occur depending on the time considered for the daily total of Rn. It was verified that the surrounding areas of the experimental field, as well as the areas of exposed soil within the field, contributed significantly to the generation of local advection of sensible heat, which resulted in the increase of the evapotranspiration.

Coeficiente de cultura e produtividade da cebola submetida a diferentes lâminas de irrigação

The present study aimed to determine crop coefficients and evaluate the productivity of onion under different irrigation levels. The experiment was conducted in the experimental field at DTCS/UNEB Juazeiro during the period from April to September 2011. For determining the ETc, daily measurements were made in evapotranspirometers. The ETo was obtained by the methods of the Class A pan (TCA) and Penman-Monteith (PM) and the Kc by: Kc = ETc/ETo. The experimental design was completely randomized with three treatments and seven replications. The examined variables were: transverse diameter, mean bulb weight, total production, commercial production, total soluble solids and titratable acidity. The Kc values found by taking as a basis the ETo determined by the TCA method with the Kp calculated using weather data obtained in situ, were very close to those determined by the PM method; the total productivity surpassed the national average by 122% for T1 (irrigation on the basis of ETc) and T3 (irrigation on the basis of ETo calculated according to PM) treatments and 86% for the T2 (irrigation on the basis of ETo calculated according to TCA) treatment; the irrigation management, based on the TCA method can provide high productivity, taking into account local climatic conditions.

Conforto e estresse térmico em ovinos no Norte da Bahia

The climate is a determining factor for the success of the productive activity, thus for greater efficiency on the farm, the animals x environment interaction should be considered because they show different responses to the peculiarities of the climate of each region. This study aimed to evaluate the thermal comfort of the Santa Ines, Dorper and undefined breed - SRD sheep, created under open sky conditions. The research was conducted at the Campus III of the University of the State of Bahia in Juazeiro, during the period November 15, 2009 to February 14, 2010. The animals were divided into four groups according to coat color: white, light brown, dark brown and black. For measurements of microclimatic conditions faced by sheep, an automatic meteorological station was installed in the experimental area, with its sensors positioned at the mean height of the animal, 50 cm above the surface. The results showed that due to high radiant heat load, resulting in a high incidence of solar radiation and high temperatures, the animals regardless of breed and coat color experienced, mainly in the afternoon, high thermal stress and discomfort.

Influence of Plastic Covering on the Microclimate in Vineyards in the São Francisco River Valley Region

Abstract Data from field experiments conducted in table grape vineyards variety of Festival in Petrolina-PE in the period fromSeptember 19 to October 12, 2010 were used to evaluate the influence of plastic cover on microclimate conditions ofvineyards in Sao Francisco River Valley region. Three treatments were studied: canopies without plastic cover (WC);with plastic cover positioned at 50 cm (PC50), and at 100 cm (PC100) above canopy. The results indicate that the plasticcover prevented the passage of about 40% of the global and net radiation, retained the relative humidity inside the can-opy, generated an increase of air temperature and marked reduction in wind speed over the canopy of treatment PC50.However, treatment PC100 had a higher incidence of short wavelength and net radiation under canopy (on the berries)than WC and PC50 treatments, resulting in more favorable weather conditions, providing about 40% greater productiv-ityinthistreatment.Therefore,thevineyardwithplasticcoverplacedat100cmabovecanopyrepresentsamoresuitablealternative to the climatic conditions of the region of the Sao Francisco River Valley.

Irrigation management methods for the production of bell pepper in agricultural substrates

This study’s objective was to assess the response and effectiveness of irrigation management systems for the production of bell pepper with different agricultural substrates, under protected conditions. The current study was conducted in a greenhouse located in Juazeiro, BA, in the northwest of Brazil. The experiment design was completely randomized in a split-plot system, with two irrigation treatments as the main plots (the drainage lysimeter and the Piché evaporimeter) and two substrates in each sub-plot (coconut fiber and pinus bark), with 5 replications per treatment. Harvest was conducted from 86 to 151 days after transplanting, and the following characteristics were evaluated: total, marketable and unmarketable yields, production per plant, fresh mass of fruits, fruit number per plant, length and diameter of fruits, length/diameter ratio, water use efficiency, pulp thickness, fruit pH, soluble solids, and titratable acidity. AGROMETEOROLOGY Article Irrigation management methods for the production of bell pepper in agricultural substrates Irai Manuela Santana Santos*, Pedro Pereira Santos Júnior, Rodrigo Rafael da Silva, Gertrudes Macário de Oliveira, Sérgio Oliveira Pinto de Queiroz Universidade do Estado da Bahia Departamento de Tecnologia e Ciências Sociais Juazeiro (BA), Brazil. *Corresponding author: irai.manuela@gmail.com Received: June 14, 2017 – Accepted: Nov. 14, 2017 No interaction effects between irrigation treatments and substrates were observed on the following variables: total yield, marketable yield, non-marketable yield, production per plant, mean mass, and diameter of marketable fruits. Irrigation treatments and substrates did not show a significant effect on bell pepper yield. Drainage lysimeter-based management and coconut fiber substrate had the best results in terms of the physical quality of fruits, whereas pinus bark-based substrate positively influenced all chemical variables and the Piché evaporimeter-based irrigation management showed a good performance raising fruit pH in relation to fruits cultivated in lysimeter with pinus bark. Additional research is required under different environmental conditions so that this crop fully expresses its yield potential.

Precipitação esperada, em diferentes níveis de probabilidade, na região de Juazeiro, BA

Os eventos de chuvas sao preponderantes para o desenvolvimento dos cultivos agricolas totalmente dependentes de sua ocorrencia. Tendo em vista que previsoes climaticas nem sempre sao precisas, tecnicas que possam auxiliar nas previsoes, como estimativas de precipitacoes, com base em niveis de probabilidade de sua ocorrencia, podem ser uma boa alternativa. Objetivou-se, neste trabalho, determinar a precipitacao pluviometrica esperada, em diferentes niveis de probabilidade, para a regiao de Juazeiro, BA bem como a epoca de menor risco de perdas na colheita de uvas finas por causa da ocorrencia de chuvas. O estudo foi realizado com dados dos registros pluviometricos diarios de uma serie de 40 anos, obtidos junto a estacao Agrometeorologica de Mandacaru no municipio de Juazeiro, BA. As estimativas mensais da precipitacao pluviometrica provavel para os niveis de 90; 80; 75; 60; 50; 45; 40; 35 e 30% de probabilidade foram obtidas pela funcao de distribuicao gama. Aplicou-se o teste de aderencia de Kolmogorov-Smirnov, ao nivel de 5% de significância para verificar o ajuste dos dados. A distribuicao gama apresentou bom ajuste para estimar a precipitacao provavel em diferentes niveis de probabilidade na regiao de Juazeiro, BA. Os valores medios de precipitacao pluvial mensal ocorreram proximo ao nivel de 40% de probabilidade. A epoca mais adequada para o cultivo de sequeiro na regiao foi o bimestre fevereiro e marco. As menores probabilidades de ocorrencia de chuva de maio a outubro proporciona menor risco de perdas na colheita de uvas finas em cultivo irrigado, na regiao de Juazeiro, BA.

AJUSTE DA EQUAÇÃO DE MAKKINK PARA O MUNCÍPIO DE JUAZEIRO-BAHIA

The estimation of reference evapotranspiration by means of empirical methods, which presents a high correlation with those of a standard method, may be a good alternative 1 Mestrando, PPGHI, Depto de Tecnologia e Ciências Sociais, UNEB, Juazeiro, BA. Av. Edgard Chastinet, SN, São Geraldo, 48900-000, Juazeiro, BA. Fone (74) 3611 7248. Email: edgoj@hotmail.com. 2 Doutora, Professora Titular, Depto de Tecnologia e Ciências Sociais, UNEB, Juazeiro, BA. Doutor, Professor Adjunto, Colegiado de Engenharia Agrícola e Ambiental/UNIVASF, Juazeiro-BA. 4 Bolsista PIBIC, Graduando Eng. Agronômica, Depto de Tecnologia e Ciências Sociais, UNEB, Juazeiro, BA. 5 Bolsista FAPESB, Graduanda Eng. Agronômica, Depto de Tecnologia e Ciências Sociais, UNEB, Juazeiro, BA. 6 Mestrando, PPGHI, Depto de Tecnologia e Ciências Sociais, UNEB, Juazeiro, BA. E. J. P. Santiago et al. for routine use in irrigation system design and management. This work had the objective of adjusting the Makkink equation for the municipality of Juazeiro-BA. Daily air temperature data were used; Solar radiation at the surface; Slope of the saturation pressure curve; Psychrometric constant and reference evapotranspiration estimated by the Penman-Monteith method. The adjustment was performed using linear regression considering data from odd years, and for validation data from even years. Angular and linear coefficients were obtained, respectively, 0.755 and 0.496; Higher than the standard Makkink equation. In the analysis of the comparative performance between the adjusted Makkink equation in relation to the standard Penman-Monteith method, an optimum score of 0.88 was found. The use of the Makkink equation with the adoption of adjusted coefficients allows precise estimates of reference evapotranspiration for the climatic conditions of Juazeiro-BA.