Modelling Sugarcane Development and Growth within Ecosmos Biophysical Model

Abstract

Sugarcane plays an important role to biofuel, electricity, and sugar production. Developing or optimizing a mechanism to predict the crop growth and yield at different spatiotemporal scales can support understanding the effects of cultivation on the ecosystem, optimize management options, and improve the operational procedures of sugarcane growers. The main objectives of this study are to update the integration of the sugarcane module into ECOSMOS(Ecosystem Model Simulator), and calibrate a parameter set for sugarcane genotypes groups. Firstly, all ECOSMOS biophysical and physiological parameters for the sugarcane module were calibrated using two micrometeorological experimental sites including eddy-covariance and biomass measurements. Secondly, sugarcane genotypes located in different regions of contrasting climate conditions were split into two groups based on their period of harvest, i.e., early or midto-late harvest season, and two parameter sets were proposed. The sugarcane module was used to estimate the yield of numerous plots at a regional scale using two different parameter sets, namely, the general parameter set and the regionally-specific parameter set, which were calibrated accordingly. The model was successful in simulating the biophysical and physiological processes of energy and carbon fluxes, soil water dynamics, and the biomass of stalks and leaves. However, the general parameter set did not perform well in all environmental conditions, and hence, a new calibration approach based on local conditions was proposed to improve the module's accuracy across environmental conditions. Although the two parameter sets can be used as a reference for sugarcane plantations in Brazil, recalibration is recommended to ensure higher accuracy before operational applications.

Keywords: sugarcane, process-based modeling, ECOSMOS