Water and Sediment Quality – Workgroup 1
As a result of residential and industrial development, harbour waters and sediments, often become enriched with nutrients and subject to sedimentation and elevated loads of pollutants, such as particulate matter, heavy metals, metalloids and organic contaminants. WG1 aims to comprehend and compare how these stressors impinge upon the natural, social and economic resources of harbours and pursue effective strategies for the management of water and sediment quality issues.
As a result of residential and industrial development, harbour waters and sediments often become enriched with nutrients and are subject to sedimentation and elevated loads of pollutants such as particulate matter, heavy metals, metalloids and organic contaminants. Water quality is also often compromised by physical modifications and built infrastructure within harbours due to changes in hydrodynamics.
WG1 currently has three streams to explore these complex issues:
A) Contaminants in global harbour sediments
Harbours in all parts of the globe have sediments contaminated with heavy metals and organic pollutants. Sources include: shipping activities (including anti-fouling paints, dry dock, loading and bunkering operations, and ship repair and building), industry (e.g. pyrogenic processes, spills and leaks), urbanisation (e.g. sewage outfall, urban run-off, stormwater inputs) and agricultural waste.
WG1 is investigating the distribution of contaminant enrichment in harbour sediments, the risk to benthic communities that these contaminants present and, where possible, the relationship between enrichment, risk and infaunal diversity. Data from Australia (Sydney, Darwin and Hobart), New Zealand (Auckland), Hong Kong, Italy (Ravenna) and Spain (Vigo) will be mapped using existing data sets in ArcGIS.
B) Hydrodynamics, water quality, and sediment transport issues in ports and harbours
Increasingly, ports in Asia are growing and developing in their capacity and associated population pressures. Invariably these ports and harbours are challenged by water quality issues, such as sedimentation, eutrophication, hypoxia and changes to the circulation as a result of land reclamation and industrialisation. A group of physical oceanographers, from a number of partner institutions, is focusing on the hydrodynamics, water quality, and sediment transport issues in ports and harbours (and associated shelf seas) in the Asia-Pacific region (at present Sydney, Darwin, Auckland, Hong Kong, Singapore, Shanghai and Qingdao).
C) Key microbial species/functional groups within harbour sediments
The structural and functional diversity of microbial communities are intricately linked with the presence and fate of pollutants and are therefore useful as bioindicators of ecosystem function. Starting in 2016, WG1 aims to build a profile of microbial communities within sediments and the water column in multi-use harbours that are subject to multiple anthropogenic stressors. The function and structure of these highly diverse microbial communities will be characterised using modern environmental sequencing – ‘omics – techniques.