Relações Hídrico-Econômicas Da Palma Forrageira Cultivada Em Ambiente Semiárido

Abstract

RELAÇÕES HÍDRICO-ECONÔMICAS DA PALMA FORRAGEIRA CULTIVADA EM AMBIENTE SEMIÁRIDO MARIA GABRIELA DE QUEIROZ1; THIERES GEORGE FREIRE DA SILVA2; SÉRGIO ZOLNIER3; SÉRVULO MERCIER SIQUEIRA E SILVA4; CARLOS ANDRÉ ALVES DE SOUZA5 E HERICA FERNANDA DE SOUSA CARVALHO6 1Doutoranda em Meteorologia Aplicada, Departamento de Engenharia Agrícola, Universidade Federal de Viçosa, mg.gabi@hotmail.com2Professor Adjunto IV, Unidade Acadêmica de Serra Talhada, Universidade Federal Rural de Pernambuco, thieres@pq.cnpq.br3Professor Titular, Departamento de Engenharia Agrícola, Universidade Federal de Viçosa, zolnier@ufv.br4Pesquisador, Instituto Agronômico de Pernambuco, servulo.siqueira@ipa.br5Mestrando do Programa de Pós-graduação em Produção Vegetal, Unidade Acadêmica de Serra Talhada, Universidade Federal Rural de Pernambuco, carlosandre08_@msn.com6Mestranda do Programa de Pós-graduação em Engenharia Agrícola, Universidade Federal do Vale do São Francisco, hericafernanda_17@hotmail.com 1 RESUMO Objetivou-se determinar índices hídrico-econômicos da palma forrageira irrigada no Semiárido brasileiro. O experimento foi conduzido em Serra Talhada, PE. O delineamento foi em blocos ao acaso, com cinco tratamentos baseados na evapotranspiração de referência e quatro repetições. Os dados do balanço de água no solo (BAS) e produtivos foram usados no cálculo de indicadores hídricos e econômicos para a cultura. Em relação aos componentes do BAS, apenas a variação do armazenamento de água revelou diferença entre os tratamentos (p < 0,05). A evapotranspiração e coeficiente da cultura apresentaram valores médios de 2,59 mm dia-1 e 0,52, nessa ordem, totalizando 985,77 mm no ciclo. As eficiências do uso de água evapotranspirada em base fresca e seca foram, em média, de 14,02 kg MV m-3 e 0,87 kg MS m-3, respectivamente. A produtividade econômica da água indicou um retorno econômico bruto de 5,50 dólares para cada m-3 de água fornecida à cultura (precipitação + irrigação), e de 6,18 US$ m-3, com base na evapotranspiração. A produtividade econômica da terra na venda de cladódios para semente e forragem (13.340 US$ ha-1e 6.000 US$ ha-1, nessa ordem) foram maiores aos relatos na literatura para outras culturas. Palavras-Chave: Coeficiente de cultura, Eficiência do uso da água, Evapotranspiração da cultura, Viabilidade econômica bruta QUEIROZ, M. G.; SILVA, T. G. F.; ZOLNIER, S.; SIQUEIRA E SILVA, S. M.; SOUZA, C. A. A.; CARVALHO, H. F. S HYDRO-ECONOMIC RELATIONS OF FORAGE CACTUS CULTIVATED IN SEMIARID ENVIRONMENT 2 ABSTRACT This study aimed to determine hydro-economic indices of cactus forage irrigated in the Brazilian Semiarid. The experiment was conducted in Serra Talhada, State of Pernambuco. The design was a randomized block with five treatments based on reference evapotranspiration in four replications. Soil water balance (SWB) and productive data were used in the calculation of water and economic indicators for crop. Regarding the components of the SWB, only the soil water storage variation revealed differences between treatments (p < 0,05). The evapotranspiration and crop coefficient showed values equal to 2.59 mm day-1 and 0.52, in that order, totaling 985.77 mm for the cycle. The evapotranspired water use efficiencies on fresh and dry basis were on averaged, 14.02 kg GM m-3 and 0.87 kg DM m-3, respectively. The water economic productivity indicated a gross economic return of 5.50 dollars for each m-3 of water supplied to the culture (rain + irrigation) and $ 6.18 m-3 dollars, based on the evapotranspiration. The land economic productivity for sale of cladode for seed and forage ($13,340 ha-1e $ 6,000 ha-1, in that order) were higher than in reports for other crops. Keywords: Crop coefficient, Water use efficiency, Crop evapotranspiration, Brute economic viability.

Meteorological variables and morphological characteristics influencing the evapotranspiration of forage cactus

“…Cladode by the species during the experiment, at the best condition (7.5 mm water depth every 7 days, 756 mm year -1 ), was much lower (only 32% of the ETo) than it was necessary for the crop demand (1,900 mm equivalent year -1 ) which according to Queiroz et al (2016), the adequate water supply is around 52% of the ETo. This fact means that in the present study, over time, the imposed water regimes and the seasonality of the rainfall gave low water supply to the crop, especially at times when the radiation intensity was high.…”

The application of agrometeorological techniques contributes to the agricultural resilience of forage cactus: A review

“…At that, for the rational management of irrigation water in a production system, it is necessary the knowledge of the water needs of the cultivation, which suffers great influence of the environment energetic requirement, of the available water in the soil, and the resistance of the plant while losing water for the atmosphere, being of importance the measurement of the evapotranspiration (ET) and the variation of the water soil storage (Δh), where the volumetric content of the water soil (θ) is of great importance for the calculation of these components (Araújo Primo et al, 2015;Queiroz et al, 2016;Carmo et al, 2017).…”

“…In addition to presenting meagre conditions derived from climate elements, extended periods of drought and irregularity in the rainfall events, Brazilian Semiarid has shown vulnerability to the climate changes, thus, the meteorological conditions are aggravated by this phenomenon (Cunha et al, 2015;Queiroz et al, 2016). These factors pose a challenge to the agricultural production, once the socioeconomic relations of the rural population of this region depend closely on these activities, which, in the region are affected by the water shortage and, consequently, reflect in the food production for the livestock (Souza et al, 2014;Marengo et al, 2017).…”

“…Forage cactus is a xerophyte species that due to its morphological and physiological characteristics it presents significant tolerance to environments with extended periods of drought. Even with these characteristics, studies have shown the successful performance of this cactus in response to the use of irrigation, with which it is possible to improve the development and productivity of this cultivation (Almeida et al, 2011;Pereira et al, 2015;Queiroz et al, 2016;Silva et al, 2017a).…”

Photosynthesis and gas exchanges of forage cactus varieties (Opuntia and Nopalea) grown under screen and irrigation

“…The plants were irrigated every 7 (seven) days, using 1/3 of the total weekly evapotranspiration, using a plastic watering can with a capacity of 10 liters of water (QUEIROZ et al, 2016). Plants were fertilized with 20 t.ha -1 of cattle manure, applied to the soil, between the rows in the implementation of the experiment and every year.…”