African Journal of
Agricultural Research

  • Abbreviation: Afr. J. Agric. Res.
  • Language: English
  • ISSN: 1991-637X
  • DOI: 10.5897/AJAR
  • Start Year: 2006
  • Published Articles: 6576

Full Length Research Paper

Performance of SMA-C model on crop evapotranspiration estimation

Bruno Patias Lena
  • Bruno Patias Lena
  • Universidade de Sao Paulo, Piracicaba-SP, Brazil.
  • Google Scholar
Rogério Teixeira de Faria
  • Rogério Teixeira de Faria
  • Universidade Estadual Paulista, Jaboticabal-SP, Brazil.
  • Google Scholar
Alexandre Barcellos Dalri
  • Alexandre Barcellos Dalri
  • Universidade Estadual Paulista, Jaboticabal-SP, Brazil.
  • Google Scholar
Luiz Fabiano Palaretti
  • Luiz Fabiano Palaretti
  • Universidade Estadual Paulista, Jaboticabal-SP, Brazil.
  • Google Scholar
Miquéias Gomes dos Santos
  • Miquéias Gomes dos Santos
  • Universidade Estadual Paulista, Jaboticabal-SP, Brazil.
  • Google Scholar


  •  Received: 07 March 2016
  •  Accepted: 23 April 2016
  •  Published: 26 May 2016

Abstract

Many simulation models found in the literature integrates data on climate and crop characteristics to provide great information on the season for different crops. The objectives of this study were: a) to measure soil water balance components of a wheat crop to determine its evapotranspiration (ETc) and crop coefficients (Kc) during the growing season; b) to use experimental data to evaluate the performance of SMA-C in estimating evapotranspiration for a wheat in Paraná State, Brazil; and c) to make adjustments to improve mod`el estimates. Two weighing lysimeters cultivated with a wheat crop were used to measure soil water storage and ETc during the growing season of a wheat crop. Reference evapotranspiration (ETo) was determined by FAO 56 method using data from a local weather station. Wheat crop coefficients were calculated by the ratio ETc/ETo, were 0.7, 1.5 and 0.6, for initial, mid and late season, respectively. The comparison of SMA-C simulations with the observed data showed inaccuracies in estimation of soil water storage due to model underestimation for ETc. Estimates were improved by adjusting the model to consider Kc measured in the field.

 

Key words: Models, lysimeters, decision-making support.