eCite Digital Repository

Measuring hypoxia induced metal release from highly contaminated estuarine sediments during a 40 day laboratory incubation experiment

Citation

Banks, JL and Ross, DJ and Keough, MJ and Eyre, BD and MacLeod, CK, Measuring hypoxia induced metal release from highly contaminated estuarine sediments during a 40 day laboratory incubation experiment, The Science of The Total Environment, 420 pp. 229-237. ISSN 0048-9697 (2012) [Refereed Article]


Preview
PDF
Restricted - Request a copy
483Kb
  

Copyright Statement

Copyright 2012 Elsevier B.V.

DOI: doi:10.1016/j.scitotenv.2012.01.033

Abstract

Nutrient inputs to estuarine and coastal waters worldwide are increasing and this in turn is increasing the prevalence of eutrophication and hypoxic and anoxic episodes in these systems. Many urbanised estuaries are also subject to high levels of anthropogenic metal contamination. Environmental O2 levels may influence whether sediments act as sinks or sources of metals. In this study we investigated the effect of an extended O2 depletion event (40 days) on fluxes of trace metals (and the metalloid As) across the sediment–water interface in sediments from a highly metal contaminated estuary in S.E. Tasmania, Australia. We collected sediments from three sites that spanned a range of contamination and measured total metal concentration in the overlying water using sealed core incubations. Manganese and iron, which are known to regulate the release of other divalent cations from sub-oxic sediments, were released from sediments at all sites as hypoxia developed. In contrast, the release of arsenic, cadmium, copper and zinc was comparatively low, most likely due to inherent stability of these elements within the sediments, perhaps as a result of their refractory origin, their association with fine-grained sediments or their being bound in stable sulphide complexes. Metal release was not sustained due to the powerful effect of metal-sulphide precipitation of dissolved metals back into sediments. The limited mobilisation of sediment bound metals during hypoxia is encouraging, nevertheless the results highlight particular problems for management in areas where hypoxia might occur, such as the release of metals exacerbating already high loads or resulting in localised toxicity.

Item Details

Item Type:Refereed Article
Keywords:hypoxia, anoxia, metal contamination, soft sediments
Research Division:Agricultural and Veterinary Sciences
Research Group:Fisheries Sciences
Research Field:Aquatic Ecosystem Studies and Stock Assessment
Objective Division:Environment
Objective Group:Ecosystem Assessment and Management
Objective Field:Ecosystem Assessment and Management of Coastal and Estuarine Environments
Author:Ross, DJ (Dr Jeff Ross)
Author:MacLeod, CK (Associate Professor Catriona MacLeod)
ID Code:77733
Year Published:2012
Web of Science® Times Cited:16
Deposited By:Sustainable Marine Research Collaboration
Deposited On:2012-05-22
Last Modified:2014-11-06
Downloads:0

Repository Staff Only: item control page