Estimativa da eficiência do uso da água no cultivo irrigado da banana (Musa sp. L.), através de sensoriamento remoto.

Abstract

Banana is one of the most consumed fruits worldwide, however, it requires high water demand to reach its maximum productive potential. In order to achieve a balance between water use and efficiency, it becomes necessary to implement integrated water resources management. The objective of this work was to determine the efficiency of water (Water Productivity-WP) use in the irrigated cultivation of the banana tree (Musa sp. L.) for the municipalities of Barbalha and Missão Velha, Ceará, Brazil, using parameters such as actual evapotranspiration rate-ETr (%), obtained through the METRIC algorithm (Mapping evapotranspiration at high resolution and with internalized calibration) and Gross Primary Productivity (GPP), by the Light Use Efficiency- LUE) both using remote sensing data. Images generated by OLI / TIRS sensors from Landsat 8 satellite, orbit 217 and point 65, were used in six days of 2016 (March 3, May 22, July 9, October 29 and November 14). meteorological data collected at the meteorological station belonging to the National Institute of Meteorology-INMET such as: air temperature, wind speed, relative humidity, dew point temperature, atmospheric pressure, solar radiation, precipitation and others used in the validation processes of the models and also in the calculation of reference evapotranspiration-ET0. The banana cultivation in the studied locality has been consolidated for more than two years, presenting biophysical parameters within the normal range and evapotranspiration rate between 75 and 100%, indicating a low water stress level. By means of the temporal space evaluation and the comparison of means by the Tukey test at 5% of probability, it is noticed that regardless of the time of cultivation and / or period of the year, the production unit SB presents the best means for the ETr (%), GPP and WP, variables by the production unit SPV and SDS. Considering the management used in the irrigation, soil and the ETr (%) obtained were close to 100%, and the GPP of 8.74 g C m-² day-¹ it is noticed that the cultivation of the production unit SB provides better efficiency in water use (1.18 kg m-³), since it maintained the productivity level around 25-30 ton ha-1.