Genetic programming-based mathematical modeling of influence of weather parameters in BOD5 removal by Lemna minor.

This study, through extensive experiments and mathematical modeling, reveals that other than retention time and wastewater temperature (Tw), atmospheric parameters also play important role in the effective functioning of aquatic macrophyte-based treatment system. Duckweed species Lemna minor is considered in this study. It is observed that the combined effect of atmospheric temperature (Tatm), wind speed (Uw), and relative humidity (RH) can be reflected through one parameter, namely the "apparent temperature" (Ta). A total of eight different models are considered based on the combination of input parameters and the best mathematical model is arrived at which is validated through a new experimental set-up outside the modeling period. The validation results are highly encouraging. Genetic programming (GP)-based models are found to reveal deeper understandings of the wetland process.