Analysis of energy fluxes and vegetation-atmosphere parameters in irrigated and natural ecosystems of semi-arid Brazil.

AUTOR(ES)
FONTE

Journal of Hydrology

DATA DE PUBLICAÇÃO

2011

RESUMO

Knowledge on evapotranspiration is essential in quantifying water use depletion and to allocate scarce water resources to competing uses. Despite that an extensive literature describes the theoretical mechanisms of turbulent water vapour transport above and within crop canopies fewer studies have examined land surface parameters within composite landscapes of irrigated crops and semi-arid natural vegetation. Aiming to improve parameterizations of the radiation and energy balance in irrigated crops and natural vegetation, micro-climatic measurements were carried out on irrigated land (vineyards and mango orchard) and natural vegetation (caatinga) in the semi-arid zone of the San Francisco River basin (Brazil) from 2002 to 2005. The fractions of 24 h incident solar radiation available for net radiation were 46%, 55%, 51% and 53%, for wine grape, table grape, mango orchard and caatinga, respectively. Daily evaporative fractions of the net available energy used as latent heat flux (kE) were 0.80, 0.88, 0.75 and 0.33 respectively. The daylight values of bulk surface resistances (rs) averaged 128 s m 1, 73sm 1, 133 s m 1 and 1940 s m 1 for wine grape, table grape, mango orchard and caatinga.

ASSUNTO(S)

uva manga pomar balanço energético evapotranspiração real rugosidade superficial vegetação natural ecossistema caatinga Água recursos hídricos brasil nordeste semi-Árido

ACESSO AO ARTIGO

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