A Simulation Model for Decomposition in Grasslands

  • H. William Hunt
Part of the Ecological Studies book series (ECOLSTUD, volume 26)


A model has been developed to simulate the dynamics of decomposers and substrates in grasslands. Substrates represented are humic material, feces, and dead plant and animal remains. Except for humic material, substrates are further divided into a rapidly and a slowly decomposing fraction. The proportion of rapidly decomposing material in a substrate is predicted from its initial nitrogen content. The belowground portion of the system is divided into layers because temperature and soil water, the most important driving variables for the model, vary with depth. Decomposition rates are predicted from temperature, water tension, and inorganic nitrogen concentration.

Taxonomic groups of decomposers are not distinguished, but a distinction is made between active and inactive states, which differ in both respiration and death rates and in that only active decomposers assimilate substrate.

The model’s predictions compare favorably to data on carbon-dioxide evolution and to litter-bag experiments, but not to ATP estimates of active microbial bioass. The model indicates a profound influence of soil depth on decomposition rates and on decomposer biomass dynamics, growth yield, and secondary productivity.


Decomposition Rate Corn Stover Humic Material Water Tension Inorganic Nitrogen Concentration 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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© Springer-Verlag New York Inc. 1978

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  • H. William Hunt

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