Publication Abstract

Feedbacks between benthic carbonmineralisation and community structure: a simulation-model analysis

D.E. Duplisea

A simulation model was constructed as ameans to establish and test causal links between organic carbon mineralisation andcommunity structure in a generalised sublittoral, soft-bottom, infaunal, temperate,coastal, marine, benthic community. Two hypothesised positive feedbacks were explicitlyincluded: bioturbation by macrofauna and sulphide accumulation and toxicity to aerobicorganisms, that link benthic organisms and the sediment chemical environment. Themagnitude and dynamics of bacterial, meiofaunal and macrofaunal biomasses, and benthic O₂consumption simulated over a seasonal regime were reasonable compared with field data. CO₂production was generally underestimated, yet within the range of published, empiricalvalues, and the dynamics compared well with empirical data. Steady state simulationsindicated a reasonable and ecologically explicable collective behaviour, such as anaerobicprocesses dominating total carbon mineralisation and sulphide oxidation accounting for themajority of benthic O₂ consumption at high carbon input levels. Sensitivityanalysis of selected model parameters indicated that the positive feedbacks ofbioturbation and sulphide toxicity were more important than other selected parameters indetermining the model outcome.

Reference:

D.E. Duplisea, 1998. Feedbacks between benthic carbon mineralisation and communitystructure: a simulation-model analysis. Ecological Modelling, 110: 19-43.