Accumulation of sulfidic sediments in a channelised inland river system, southern Australia
- Authors: Wong, Vanessa , Cheetham, Michael , Bush, Richard , Sullivan, Leigh , Ward, Nicholas
- Date: 2016
- Type: Text , Journal article
- Relation: Marine and Freshwater Research Vol. 67, no. 11 (2016), p. 1655-1666
- Full Text: false
- Reviewed:
- Description: Accumulation of sulfidic sediments in freshwater environments is a relatively recent phenomenon and an emerging environmental issue. In the present study, benthic sediments along short (
Mobilisation, alteration, and redistribution of monosulfidic sediments in inland river systems
- Authors: Cheetham, Michael , Wong, Vanessa , Bush, Richard , Sullivan, Leigh , Ward, Nicholas , Zawadzki, Atun
- Date: 2012
- Type: Text , Journal article
- Relation: Journal of Environmental Management Vol. 112, no. (2012), p. 330-339
- Full Text: false
- Reviewed:
- Description: The accumulation of monosulfidic sediments in inland waterways is emerging as a major environmental issue. Mobilisation and suspension of monosulfidic sediments can result in deoxygenation, acidification of the water column and mobilisation of trace metals. The controls on monosulfidic sediment mobilisation and the critical thresholds for its scour and entrainment have not been established. This study examines the effect of a minor flood event (average return interval of 5 years) on sulfidic sediment scour in the Wakool River in southern NSW, Australia. Five profiles were sampled within a small (~300 m) reach before and after a minor flood event to determine the degree of sediment scour and transport. The results indicate substantial scour of both monosulfidic sediments and underlying bed sediments (approximately 2100 m3). Changes in the sediment geochemistry suggest large concentrations of monosulfidic sediments had been suspended in the water column, partially-oxidised and redeposited. This is supported by 210Pb results from one of the profiles. These results suggest that these monosulfidic sediments can move as bed load during minor flood events. © 2012 Elsevier Ltd.
Monosulfidic black ooze accumulations in sediments of the Geographe Bay area, Western Australia
- Authors: Ward, Nicholas , Bush, Richard , Burton, Edward , Appleyard, Steve , Wong, Stephen , Sullivan, Leigh , Cheeseman, Paul
- Date: 2010
- Type: Text , Journal article
- Relation: Marine Pollution Bulletin Vol. 60, no. 11 (2010), p. 2130-2136
- Full Text: false
- Reviewed:
- Description: Mobilisation of sedimentary monosulfidic black ooze (MBO) may result in rapid deoxygenation and acidification of surface waters, and release of potentially toxic metals. This study examines the extent and nature of MBO accumulation in the Geographe Bay area, Western Australia. MBO accumulations were found to be widespread in benthic sediments of the Geographe Bay area with acid-volatile sulfide (AVS) contents as high as 320μmolg-1. The MBO materials often had unusually high dissolved sulfide (S-II) concentrations in their pore-waters (up to 610mgL-1) and elevated elemental sulfur (S0) contents (up to 51μmolg-1). Dissolved S-II is able to accumulate due to limited iron availability and S0 is largely its partial oxidation product. The availability of organic carbon and Fe limited MBO accumulation at many sites. A comparison of AVS and simultaneously extracted metal (SEM) concentrations has shown that metals are likely to be bound in sulfide complexes. © 2010 Elsevier Ltd.