01868naa a2200229 a 450000100080000000500110000800800410001902200140006010000260007424501180010026000090021852011650022765000230139265000230141565000200143865000240145865300270148270000180150970000190152770000240154677300680157020299882016-03-17       2015    bl uuuu     u00u1 u    #d  a1808-85461 aTEIXEIRA, A. H. de C.  aWater productivity assessments with Landsat 8 images in the Nilo Coelho irrigation scheme.h[electronic resource]  c2015  aThe Nilo Coelho (NC) irrigation scheme, located in the Brazilian semi-arid region, is an important irrigated agricultural area. Land use change effects on actual evapotranspiration (ET), biomass production (BIO) and water productivity (WP) were quantified with Landsat 8 images and weather data in this scheme covering different thermohydrological conditions. The SAFER algorithm was used for ET acquirements while the Monteith?s radiation model was applied to retrieve BIO. For classifying irrigated crops and natural vegetation, the SUREAL model was used with a satellite image representing the driest period of the year. The average values for ET, BIO and WP in irrigated crops, ranged, respectively, from 1.6 ± 1.9 to 4.2 ± 1.9 mm day-1; 59 ± 86 to 146 ± 91 kg ha-1 day-1; and 2.0 ± 1.5 to 3.0 ± 1.2 kg m-3. The corresponding ranges for natural vegetation (?Caatinga?) were from 1.2 ± 1.8 to 2.6 ± 1.8 mm day-1; 43 ± 78 to 76 ± 78 kg ha-1 day-1; and 1.6 ± 1.4 to 2.7 ± 1.1 kg m-3. The incremental values, which represent the effects of the replacement of natural vegetation by irrigated crops, were 40, 54 e 23%, for ET, BIO e WP, respectively.  aBiomass production  aEvapotranspiration  aLand use change  aEvapotranspiração  aProdução de biomassa1 aLEIVAS, J. F.1 aANDRADE, R. G.1 aHERNANDEZ, F. B. T.  tIrriga, Botucatugv. 1, n. 2, edição especial, p. 1-10, 2015.