ABSTRACT: Awareness of evapotranspiration (ET) and crop coefficient (Kc) is necessary for irrigation management in coffee crops. ET and Kc spatial variabilities are disregarded in traditional methods. Methods based on radiometric measurements have potential to obtain these spatialized variables. The Kc curve and spatial variability of actual evapotranspiration (ETa) were determined using images from Landsat 8 satellite. We used images of young and adult coffee plantations from OLI (Operational Land Imager) and TIRS (Thermal Infrared Sensor) sensors over a two-year period. Evapotranspiration was estimated using the Surface Energy Balance Algorithm for Land (SEBAL). Moreover, the reference evapotranspiration (ETo) was estimated through the Penman-Monteith method. We obtained the values for the evapotranspiration fraction (ETf), analogous to Kc, according to ET and ETo values. The study was conducted in Buritis, Minas Gerais State, Brazil, in areas cropped with Coffea arabica irrigated by central pivots. A comparative analysis was made using different statistical indices. Average ETa was 2.17 mm d−1 for young coffee plantations, , and the Kc mean value was 0.6. For adult coffee plantations, average ETa was 3.95 mm d−1, , and the K mean value was 0.85. The ET and K data obtained based on the SEBAL algorithm displayed similar values to studies that used traditional methods. This model has huge potential to estimate ET of different stages of coffee plantation for the region studied.

RESUMO A Espanha possui um terço de toda área irrigada da Europa. A área irrigada no país responde por 15% da área cultivada e quase 60% da produção agrícola nacional. O conhecimento da variabilidade espacial e temporal da evapotranspiração de referência (ETo) e da teoria probabilística dos eventos extremos é um ponto essencial para elaboração de projetos sustentáveis de irrigação. O objetivo do trabalho foi analisar a distribuição de frequência que melhor descreve a ETo visando o dimensionamento de sistemas de irrigação da região de Andaluzia, Espanha. Foram utilizados dados de ETo de 56 estações meteorológicas com extensão das séries entre os anos de 2001 a 2015. Estes valores de ETo foram acumulados em três períodos consecutivos de dias. Para todos os períodos acumulados ajustaram-se nove distribuições de probabilidade. A distribuição de probabilidade que melhor descreveu a ETo visando o dimensionamento de sistemas de irrigação da região foi a Gumbel II. A ETo diária máxima a ser considerada em projetos de irrigação na mesma região é de 10 mm, em média. Já as ETo acumuladas em períodos de 5, 10 e 30 dias que devem ser consideradas são, em média, de 42 mm, 78 mm e 224 mm, respectivamente.

ABSTRACT Spain contains a third the entire irrigated area of Europe, accounting for 15% of the cultivated area of the country and almost 60% of the national agricultural production. Knowledge of the spatial and temporal variability of reference evapotranspiration (ETo) and the probabilistic theory of extreme events is crucial for the elaboration of sustainable irrigation projects. The objective of this work was to define the frequency distribution that best describes ETo for the design of irrigation systems in the region of Andalusia. We used ETo data for the period 2001 to 2015 from 56 meteorological stations. The values were accumulated over three consecutive days. For all accumulated periods, nine probability distributions were adjusted. The probability distribution that best described ETo for the design of irrigation systems in the region was the Gumbel II distribution. The maximum daily ETo to be considered in irrigation projects in this region is, on average, 10 mm. The accumulated ETo for periods of 5, 10, and 30 days that should be considered are, on average, 42 mm, 78, mm and 224 mm, respectively.

RESUMO. O objetivo deste trabalho foi apresentar uma nova metodologia para dimensionamento de RCAPs com base em modelagem probabilística. Para determinar uma demanda hídrica hipotética, utilizou-se a cultura do Eucalipto cultivada em casa de vegetação (CV). Dados meteorológicos foram utilizados para estimar, demanda (evapotranspiração) e oferta (precipitação incidente na cobertura da CV). A distribuição de probabilidade de Wakeby apresentou o melhor ajuste aos dados de precipitação; portanto, foi utilizada para modelar a curva de permanência do escoamento gerado na cobertura da CV e, assim, determinar o volume de um RCAP para suprir a demanda da cultura. Para um tempo de retorno (T) de 10 anos de excedente hídrico da demanda e de déficit hídrico da oferta, obteve-se um volume do RCAP de 13,60 m³. Assim, pela combinação de ocorrência simultânea dos eventos, pode-se concluir que a metodologia proposta permite dimensionar reservatórios com alta segurança de atendimento da demanda (T = 100 anos) e, consequentemente, com menor custo de implantação, comparado com as abordagens separadas (T = 10 anos).

ABSTRACT. The aim of this study was to propose a new methodology for reservoir rainwater dimensioning based on probabilistic modeling. Eucalyptus seedlings grown in a greenhouse were used to obtain a hypothetical water demand. Meteorological data were used to estimate the demand (evapotranspiration) and offer (rainfall over the greenhouse coverage). The probability distribution of Wakeby presented the best fit for the rainfall data; therefore, a Wakeby distribution was used to model the flow-duration curve of the greenhouse coverage. For a payback period (T) of 10 years of surplus water demand and water supply deficit, a reservoir with 13.60 m³ was obtained. The proposed methodology combined the simultaneous occurrence of the events to enable the scaling out of a reservoir with high safety to supply the required demand (T = 100 years) and therefore enables a lower cost of deployment compared to each approach separately (T = 10 years).

RT-PCR was used for amplifying Piaractus mesopotamicus growth hormone (GH) cDNA obtained from mRNA extracted from pituitary cells. The amplified fragment was cloned and the complete cDNA sequence was determined. The cloned cDNA encompassed a sequence of 543 nucleotides that encoded a polypeptide of 178 amino acids corresponding to mature P. mesopotamicus GH. Comparison with other GH sequences showed a gap of 10 amino acids localized in the N terminus of the putative polypeptide of P. mesopotamicus. This same gap was also observed in other members of the family. Neighbor-joining tree analysis with GH sequences from fishes belonging to different taxonomic groups placed the P. mesopotamicus GH within the Otophysi group. To our knowledge, this is the first GH sequence of a Neotropical characiform fish deposited in GenBank.