Introduction
- Module contaminant in MARS model is associated with module subtance (Module Substance).
- The module contaminant offers a choice of generic reactions already programmed that represent a number of conventional biogeochemical transformations. The reactions take place between the different variables which may for example represent different species of a contaminant. The type of each reaction, the parameters that determine each one and the associated variables are defined in a data file (Type of reactions simulated in module MET&OR)
- Contaminants speciation is treated by considering the different species which may have different physical behaviors (dissolved/particulate), reactivity, bioavailability or specific toxicity. The main processes involved are sorption processes with respect to dissolved ligands and particulate substrates, transformation processes (degradation, hydrolysis ..), and transfer process (volatilization)
- These processes are incorporated in the equations of conservation of mass through terms “sinks and sources”. For some very fast or equilibrium reactions, a separate operator is used to a posteriori correct at each time step the concentrations of each chemical species involved.
- Process definition, characteristics of the contaminants and parameters required to define the different reactions are read directly into data files, easy to use.
- Associated with a module that describes the biological ecosystem, this module allows to study the transfer of contaminants from the abiotic environment to the first link in a food chain (phytoplankton - microzooplankton). It has been used in combination with ECO3M module (developed by M.I.O. - University of the Mediterranean - Baklouti et al, 2006).
- The implementation of this module (Implementation of MET&OR module) requires to complete :
