| Stable isotope analysis of food-web structure of Fly River flood plain water bodies |
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Author: Wetlands Research and Management P/L (Dr A. Storey) Date: September 2006 Sampling of primary producers and primary, secondary and higher consumers was conducted at eight flood plain sites in February 2005 to compare aquatic food web structure and test for possible mine effects. Sites consisted of three control forested oxbow lakes upstream of the influence of the mine, three exposed forested oxbow lakes downstream of the mine and two blocked valley lakes. Sampling involved the collection of primary sources (algae and terrestrial plants) and higher consumers (prawns, aquatic insects and fish) at each site. Stable isotopes of nitrogen and carbon were then determined in the laboratory to determine sources of carbon (energy) supporting aquatic food webs. Prior to analysis, carbon isotope data were standardised to allow for between-site differences in the carbon signature of the algal sources; riparian sources had the same signatures across sites. |
