COMPARISON AMONG METHODS OF ESTIMATE OF EVAPOTRANSPIRATION OF REFERENCE IN THE NORTH AREA OF BAHIATo determine the water needs of a culture in conditions no-pattern, it is fundamental the knowledge of the reference evapotranspiration (ETo). The method of Penman-Monteith is considered by FAO, as pattern for estimate of ETo. However, in function of the number of meteorological variables used in that method, it has been using several other methods in the irrigation handling. The present work had as objective compares, through dear daily values for the method of Penman-Monteith, the acting of the method of the Class A pan and the methods of Hargreaves-Samani and Makkink for the north area of Bahia. The data used to esteem ETo were obtained in the automatic meteorological station of DTCS/UNEB, Juazeiro, BA. The results showed that the methods of Hargreaves-Samani and Makkink, that use as entrance variable the air temperature and global solar radiation, presented good acting, both with coefficient "c" = 0.76. The method of the Class A pan, although very used in the handling of the irrigation, it showed acting just to regulate, with coefficient "c" = 0.62.
RESUMOO clima é fator determinante para o sucesso da atividade produtiva; logo, a interação animal x clima deve ser considerada visando a uma eficiência maior na exploração pecuária, de vez que os animais apresentam diferentes respostas às peculiaridades do clima de cada região. Neste trabalho objetivou-se avaliar o conforto térmico de ovinos das raças Santa Inês, Dorper e Sem Raça Definida -SRD, criados a céu aberto. A pesquisa foi conduzida no Campus III da Universidade do Estado da Bahia, em Juazeiro, no período de 15 de novembro de 2009 a 14 de fevereiro de 2010. Os animais foram divididos em quatro grupos, de acordo com a cor da pelagem: branco, castanho-claro, castanho-escuro e preto. Para se obter medidas reais das condições microclimáticas enfrentadas pelos ovinos, uma estação meteorológica automática foi instalada na área experimental, com seus sensores posicionados na altura média dos animais, 50 cm acima da superfície. Os resultados indicaram que, devido à alta carga térmica radiante resultante da grande incidência de radiação solar e as elevadas temperaturas os animais, independentemente da raça e da cor da pelagem experimentaram, principalmente no período da tarde, desconforto e estresse térmico elevado. Palavras-chave: temperatura elevada, radiação solar, condições climáticas adversasComfort and heat stress in sheep in Northern Bahia ABSTRACT 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 Inês, 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. Neiva et al. (2004) afirmam que para a máxima produtividade é necessário que a temperatura esteja dentro de uma faixa adequada, também chamada zona de conforto térmico, na qual não há gasto de energia ou atividade metabólica para aquecer ou esfriar o corpo.Estudos realizados por Brasil et al. (2000), relativos aos efeitos do estresse térmico na produção de cabras Alpinas mostraram que, em razão da temperatura do ar elevada e da umidade relativa do ar baixa, o estresse térmico proporcionou, durante o período da tarde, aumento da freq...
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.