Open AccessControl of biogeochemical cycling by mobility and metabolic strategies of microbes in the sediments: an integrated model study
Author(s) -
Wirtz Kai W.
Publication year - 2003
Publication title -
fems microbiology ecology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.377
H-Index - 155
eISSN - 1574-6941
pISSN - 0168-6496
DOI - 10.1016/s0168-6496(03)00196-x
Subject(s) - biogeochemical cycle , biology , biological system , sediment , methanogenesis , mineralization (soil science) , ecology , dormancy , carbon cycle , microbial metabolism , biochemical engineering , environmental chemistry , soil science , methane , bacteria , soil water , botany , ecosystem , environmental science , paleontology , chemistry , germination , engineering , genetics
An integrated modeling framework was developed to assess physical, biological and chemical processes in the sediment and at the sediment–water interface. Special focus is laid on the description of different functional groups of bacteria as defined according to their metabolic pathways, including fermentation, methanogenesis and oxidation of high and low molecular mass dissolved organic carbon, ammonium as well as other reduced compounds. The model is subjected to a new validation method which allows for an appropriate representation of remaining uncertainties. It is also able to reproduce two‐dimensional gradients in all state variables induced by a pore‐water velocity field typical for permeable sediments. Another improvement with respect to many classical models follows from the simulation of adaptive changes in dormancy and motility strategies. Within an extensive analysis stage, the evolutionary stability of these strategies is investigated under a variable hydrodynamical regime. The results show that optimal behavior in terms of adhesion and readiness to dormancy shifts differ between functional groups. This pattern is compared to recent empirical findings and discussed in relation to the confidence limits of the overall methodology. In the numerical experiments, also the effect of variable microbial strategies on the total carbon mineralization of the sediment is determined.