Development of an artificial "living" sediment to study the effects of metal contamination in Antarctic marine ecosystems.

Metadata record for data from ASAC Project 2946. Public Shallow nearshore marine habitats are rare in the Antarctic but human activities have led to their contamination. Preliminary studies suggest the characteristics of Antarctica nearshore sediments are different to elsewhere and that contaminant partitioning and absorption, and hence bioavailability, will also be very different. Predictive exposure-dose-response (effects) models need to be established to provide the theoretical basis for the development of sediment quality guidelines to guide remediation activities. Such a model will be possible through the development of an artificial 'living' sediment, which can be used to understand physical and chemical properties that control partitioning and absorption of contaminants. Taken from the 2009-2010 Progress Report: Project objectives: 1. Collate and review existing knowledge on sediment properties in nearshore marine sediments in Antarctica to determine their physical, chemical and microbiological properties and identify gaps in our knowledge of sediment characteristics 2. Construct a range of artificial sterile sediments taking into account characteristics of naturally occurring nearshore sediments in the Antarctic. Examine physical and chemical properties of these sediments and understand the properties that control partitioning of contaminants by manipulation of bulk sediment composition and measuring the adsorption isotherms of important metal contaminants (Cu, Cd, Pb, As, Sn, Sb) in these artificial sediments 3. Produce 'living' sediments by inoculation of sterile sediments with Antarctic bacteria and diatoms that will support natural microbial communities. Examine physical and chemical properties of these sediments and understand the properties that control the partitioning and absorption of contaminants by manipulation of the bulk sediment composition and spiking metal contaminants into these artificial sediments. Progress against objectives: Using published literature the approximate composition of Antarctic sediments was determined. Representative sediment phases were collected form a uncontaminated environment, the chemical composition measured and absorption capacities of Cd and Pb established. The download file contains several excel spreadsheets. Some information about them is provided below: My =ref is reference in thesis EN =is endnote reference Nearby station = is closest known reference point to where samples collected TOC = total organic carbon TOM = Total organic matter BPC =biogenic particulate carbon TN = total nitrogen TP = Total phosphorus BSi = biogenic silica Ci = initial aqueous phase concentration qe = solid phase equilibrium concentration