implementation of EF from SEBS in a lue model in a rapeseed cropland

Abstract

In assessment of global carbon cycle, evaluation of gross primary production, GPP, of an ecosystem is the main endeavour. The most adequate way to address this study is to apply a Light Use Efficiency, LUE, model in combination with an Eddy Covariance, EC, system. In this paper, evaporative fraction, EF, from two different databases (ground-based measurements and calculated by the Surface Energy Balance System, SEBS, algorithm developed at ITC) are applied to a LUE model in order to calculate a final e0 value which is the maximum PAR conversion efficiency of the cropland. The LUE model was found to fit properly using both EF databases, with squared correlation coefficients of 0.89 and 0.81 for ground measurements and SEBS results, respectively. Final values for máximum efficiency were of 2.82����0.19 gC MJ-1 (measured EF) and 2.59����0.23 gC MJ-1 (SEBS). All these results were obtained with FPAR provided by MERIS.