Publication Date:
2017-05-19
Description:
Pore water profiles from 24 stations in the
South Atlantic (located in the Guinea, Angola, Cape,
Guyana, and Argentine basins) show good correlations
of oxygen and silicon, suggesting microbially mediated
dissolution of biogenic silica. We used simple analytical
transport and reaction models to show the tight coupling
of the reconstructed process kinetics of aerobic
respiration and silicon regeneration. A generic transport
and reaction model successfully reproduced the
majority of Si pore water profiles from aerobic respiration
rates, confirming that the dissolution of biogenic
silica (BSi) occurs proportionally to O2 consumption.
Possibly limited to well-oxygenated sediments poor in
BSi, benthic Si fluxes can be inferred from O2 uptake
with satisfactory accuracy. Compared to aerobic
respiration kinetics, the solubility of BSi emerged as
a less influential parameter for silicon regeneration.
Understanding the role of bacteria for silicon regeneration
requires further investigations, some of which
are outlined. The proposed aerobic respiration control
of benthic silicon cycling is suitable for benthic–pelagic
models. The empirical relation of BSi dissolution to
aerobic respiration can be used for regionalization assessments
and estimates of the silicon budget to in
crease the understanding of global primary and export
production patterns.
Type:
Article
,
PeerReviewed
Format:
text
DOI:
10.1007/s00367-009-0181-3
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