Results

Temporal samples collected from the Calliope Estuary at Gladstone, Queensland, showed that frequently sites moved from having an unstressed healthy community to a stressed community, and vice versa. This probably indicates natural high variability in the estuarine environment and is a problem that will plague any attempts to assign estuarine communities into stressed and unstressed states of health. Our work with k-dominance curves from these four Australian states suggested that at any one time approximately 15% of Australian estuarine macrobenthic communities indicated they were collected from environmentally stressed sites, 15% had communities indicative of possible environmental stress and approximately 70% of estuarine macrobenthic communities indicated a healthy and unstressed environment. We do not know if these ratios are natural or the result of present day modified estuarine environments.

Our project demonstrated that AusRivAS type models can be developed for Australian estuarine environments but suggested that for the macrobenthic communities more work would be required to increase the numbers of taxa expected to occur in samples. The work demonstrated that an AusRivAS approach does generate a data set that allows regional and national assessment of estuarine health. It is worth investigating if estuarine health could be better assessed using an AusRivAS type model using meiobenthos rather macrobenthos.

Our work has also shown that it is relatively easy to assess estuarine health using k-dominance curves with samples collected by different methods at different times and from different regions. Such samples were shown to be good for monitoring an improvement to environmental health. Presumably they could also be used to detect deteriorating environmental conditions. This method appears ideal for assessing how catchment management programs are influencing estuarine communities.

Further Reading

General article in PDF format on using benthic macrofauna to assess Australian estuarine health published by Land and Water Resources R&D Corporation. This publication is to be cited as Moverley, J.H., 2000, Estuarine Health Assessment Using Benthic Macrofauna. Rivers for the Future 12:33-36

Download the artilce: Estuarine Health Assessment Using Benthic Macrofauna.(315 kb)

You will need Adobe Acrobat to view the article, a free download is available from http://www.adobe.com/products/acrobat/readstep.html