A manipulative field experiment examining the effect of contaminated sediment on the recruitment of soft-sediment infauna (Mar 1998 - Feb 1999).

Brief description

The effect of location and sediment contamination on recruitment of soft-sediment assemblages were examined in field experiment at Casey Station, East Antarctica. Four locations were used, a polluted bay adjacent to an old disused tip site (Brown Bay), a bay adjacent to the Casey Station sewage outfall, and two undisturbed control locations in O'Brien Bay. At each location two types of defaunated sediment (polluted and control) were placed 12 - 18 m, in experimental trays. Half of the experimental sediments were left in place over the Austral winter, from March - November, and the remaining sediments were collected after a total of one year, in February 1999.

There were large differences in recruitment between the two locations and significant differences between the polluted and control sediment. There were not only differences in abundance of taxa and assemblage structure but also in spatial variability and variability of populations of certain taxa, with recruitment to the control locations more variable than polluted locations, and recruitment in the control sediment more variable than the polluted sediment. The majority of fauna recruiting to the experiment were highly motile colonizing species with non-pelagic lecithotrophic larvae, usually brooded and released as dispersing juveniles, such as gammarids, tanaids, isopods and gastropods.

A total of 64 recruitment samples were collected after 9 months and 52 samples after one year. Samples were sieved at 500 micro m and sorted mainly to species.

Samples are rows in data sheet. Site codes include place name (e.g. BB2) and experimental treatment (e.g. C1 - control 1). See accompanying sheet for full details of codes, including species names. Sediment chemistry data are means (and standard errors) for each treatment (averaged over 2 trays).

Also links to ASAC 1100.

The fields in this dataset are:

Species
Site
Sample
Abundance
Toxicity
Arsenic
Cadmium
Copper
Lead
Silver
Zinc

Lineage

Progress Code: completed

Statement: Gammarid, Isopod, gastropod faunas identified at the Australian Museum. Remaining faunas identified by J. Stark.