A modelling approach for estimating long-term and seasonal CaCO₃ dissolution rates
A computer model is developed to simulate transport and CaCO₃dissolution in the unsaturated zone. The model incorporates daily and seasonal variations in weather inputs, runoff and recharge, water temperature, the vertical distribution of water and solutes, carbon dioxide generation and chemical equilibrium speciation. Model predictions are compared to field CaCO₃ dissolution rates and to data relating soil gas carbon dioxide and evapotranspiration. The model demonstrates that seasonal and long-term variations in recharge and CO₂ generation rates contribute to seasonal and long-term variations in CaCO₃ dissolution.