We are currently extending our ecological model ERGOM into the sediment. The result will be a coupled ecosystem - early diagenesis model. Although some processes are the same in the sediment and the water column, several additional processes, especially concerning the iron cycle, had to be added in the sediment to reproduce realistic pore water profiles.

This talk will illustrate three things:

  • Our approach which processes and state variables to include to make the model able to realistically simulate diagenesis in sandy to muddy sediments with special focus on pH in the pore water
  • Efficient numerical treatment of vertical diffusion, especially of oxygen, to allow for large time steps in spite of thin layers
  • Automatic code generation as a method which allows efficient model development

The work is part of the project SECOS which aims at quantifying sedimentary services (denitrification, retention, burial of nutrients) in the German coastal areas.