Análises dos componentes dos balanços de radiação e de água por sensoriamento remoto em videiras para mesa no município de Petrolina-PE, Brasil

Abstract

To achieve sustainable development and to ensure water availability in irrigated vineyards, modelling is important to estimate the radiation and water balances components at the farm scale. Landsat satellite images and an agro-meteorological station were used together models for quantification of these components in a commercial table grape farm, with a mixture of varieties, located in Petrolina municipal district, Brazil, which showed good agreements with field measurements. Considering the radiation balance components, the mean values of surface albedo (a0) ranged from 0.13 \ub1 0.02 to 0.16 \ub1 0.01; the surface temperature (T0) from 300.9 \ub1 1.3 K to 304.8 \ub1 2.2 K, and the NDVI from 0.75 \ub1 0.07 to 0.79 \ub1 0.09. In relation to the water balance components, the variation in the mean values of the soil moisture at 40 cm depth was from 0.21 \ub1 0.11 cm3 cm-3 to 0.26 \ub1 0.10 cm3 cm-3. The application of the models with agro-meteorological data of 2009 allowed the determination of the total actual evapotranspiration (ET) and the crop coefficient (Kc) for the generalized growing season (GS) in the second half of that year. The values for well irrigated vineyards varied, respectively from 440 to 550 mm GS-1 and 0.74 a 0.90. The similarity of the models results with field measurements and the trend with the crop stages gave confidence in their use with applicability in the semi-arid region of Brazil.Pages: 71-7