Show simple item record  

dc.contributor.authorVopel, Kay
dc.contributor.authorPilditch, Conrad A.
dc.contributor.authorWilson, Peter Stanley
dc.contributor.authorEllwood, Michael J.
dc.identifier.citationVopel, K., Pilditch, C.A., Wilson, P. & Ellwood, M.J. (2010). Oxidation of surface sediment: effects of disturbance depth and seawater flow speed. Marine Ecology Progress Series, 392, 43-55.en_NZ
dc.description.abstractPeriodic disturbance of surface sediment is a natural feature of marine environments. Following exposure to oxygenated seawater, the disturbed sediment oxidises leading to the recovery of its surface chemistry. Despite its importance for the ecology of the sediment–water interface, the dynamics of this recovery is not well known. We studied the effects of disturbance depth and seawater flow speed on the oxidation of estuarine cohesive sediment in a laboratory flume with microelectrodes. We removed surface sediment to 2 depths (5 and 50 mm) and then observed changes in sediment O₂ distribution and consumption over 1 h under conditions of slow and fast flow (3.5 and 7.5 cm s–1). Measurements were repeated 1 d later. The consumption of O₂ in the treated sediments reached a ‘quasi stable state’ within 7 h (50 mm depth) and 16 h (5 mm depth) characterised by very slow changes due to slow oxidation of reduced solids. Faster flow increased the rate at which sediment from 50 mm depth oxidised but not that of the sediment from 5 mm depth. After 20 to 24 h, sediments disturbed to 50 and 5 mm depths still differed in O₂ distribution and consumption, both from each other and from the pre-treatment sediment. Differences in the response of pore water O₂ distribution to an abrupt increase in flow speed (3.5 to 7.5 cm s–1) were also still evident at this time. Our measurements confirmed the results of previous theoretical analyses in that they indicate that the duration of the recovery of the surface sediment chemistry from disturbance and the chemical properties of the recovering sediment are controlled by the kinetics of solute and solid oxidation. Oxidation of reduced solids in disturbed sediment can result in a characteristic chemical signature at the sediment surface that lasts in the order of at least days.en_NZ
dc.subjectcohesive sedimenten_NZ
dc.subjectoxygen fluxen_NZ
dc.subjectsediment respirationen_NZ
dc.titleOxidation of surface sediment: effects of disturbance depth and seawater flow speeden_NZ
dc.typeJournal Articleen_NZ
dc.relation.isPartOfMarine Ecology Progress Seriesen_NZ

Files in this item


There are no files associated with this item.

This item appears in the following Collection(s)

Show simple item record