Spatial variability of benthic diatom communities in the Windmill Islands, Antarctica.

A hierarchical, 3-level, nested design was used. The highest hierarchical level consisted of six locations. Two of these locations, Brown Bay and Shannon Bay, have been contaminated with heavy metals (Stark et al., 2003; Snape et al., 2001); Brown Bay has also been contaminated with petroleum hydrocarbons (Snape et al., 2001). The remaining four locations are more distant from Casey Station and were used as control locations. These locations were Denison Island, Odbert Island, O'Brien Bay and Sparkes Bay. A full description of these sites is given below.

Within each location two sites were selected approximately 100 m apart. Within each site, two plots were sampled (~ 10 m apart). Although the sampling program had been designed for four replicates within each plot, the patchy distribution of bottom sediments in the Windmill Islands restricted this to two replicate samples (~ 1 m apart) per plot. Samples were collected using an Eckman grab sampler, deployed from a boat. To minimise the potential influence of water depth, all samples were collected from 8 m water depth. Samples were collected within a three day period in early February when no sea-ice was present.

Diatom data are presented as the relative abundances of benthic species. Samples are identified xyz where x = first initial of sample location (or first 2 initials where 2 locations start with the same letter), y = plot number (plots 1 and 2 represent site 1, while plots 3 and 4 are from site 2), and z = replicate number (a or b). Abbreviations used for species are shown in the separate file sp_list.

This work was completed as part of ASAC project 1130 (ASAC_1130) and project 2201 (ASAC_2201).

Public summary from project 1130:

Algal mats grow on sea floor in most shallow marine environments. They are thought to contribute more than half of the total primary production in many of these areas, making them a critical food source for invertebrates and some fish. We will establish how important they are in Antarctic marine environments and determine the effects of local sewerage and tip site pollution. We will also investigate the impact on the algal mats of the additional UV radiation which results from the ozone hole.

Public summary from project 2201:

As a signatory to the Protocol on Environmental Protection to the Antarctic Treaty Australia is committed to comprehensive protection of the Antarctic environment. This protocol requires that activities in the Antarctic shall be planned and conducted on the basis of information sufficient to make prior assessments of, and informed judgements about, their possible impacts on the Antarctic environment. Most of our activities in the Antarctic occur along the narrow fringe of ice-free rock adjacent to the sea and many of our activities have the potential to cause environmental harm to marine life. The Antarctic seas support the most complex and biologically diverse plant and animal communities of the region. However, very little is known about them and there is certainly not sufficient known to make informed judgements about possible environmental impacts

The animals and plants of the sea-bed are widely accepted as being the most appropriate part of the marine ecosystem for indicating disturbance caused by local sources. Attached sea-bed organisms have a fixed spatial relationship with a given place so they must either endure conditions or die. Once lost from a site recolonisation takes some time, as a consequence the structure of sea-bed communities reflect not only present conditions but they can also integrate conditions in the past. In contrast, fish and planktonic organisms can move freely so their site of capture does not indicate a long residence time at that location. Because sea-bed communities are particularly diverse they contain species with widely differing life strategies, as a result different species can have very different levels of tolerance to stress; this leads to a range of subtle changes in community structure as a response to gradually increasing disturbance, rather than an all or nothing response.

This project will examine sea-bed communities near our stations to determine how seriously they are affected by human activities. This information will be used to set priorities for improving operational procedures to reduce the risk of further environmental damage.

The fields in this dataset are:

Species

Site

Abundance

Benthic

Identification info

Alternate title: Spatial variability of benthic diatom communities in the Windmill Islands, Antarctica.

Date (Publication): 2003-06-11

Edition: 1

Citation identifier

Dataset DOI

Title: Information and documentation - Digital object identifier system

Date (Publication): 2012-04-23

Citation identifier: ISO 26324:2012

Citation identifier: doi:10.4225/15/5ae16f9d43867

Originator

Riddle, M.J., McMinn, A. and Cunningham, L.K.

Publisher

Australian Antarctic Data Centre

Principal investigator

RIDDLE, MARTIN J.

Australian Antarctic Division

203 Channel Highway

Kingston

Tasmania

7050

Australia

Principal investigator

MCMINN, ANDREW

Institute of Marine and Antarctic Studies

University of Tasmania

Private Bag 77

Hobart

Tasmania

7001

Australia

+61 3 6266 2980

+61 3 6226 2973 (facsimile)

Principal investigator

CUNNINGHAM, LAURA KAY

Australian Antarctic Division

203 Channel Highway

Kingston

Tasmania

7050

Australia

Collaborator

CUNNINGHAM, LAURA KAY

Australian Antarctic Division

203 Channel Highway

Kingston

Tasmania

7050

Australia

Name: CAASM Metadata

Website: https://data.aad.gov.au/metadata/records/Diatom_spatial_var

Status: Completed

Custodian

AU/AADC > Australian Antarctic Data Centre, Australia - AADC, DATA OFFICER (DATA CENTER CONTACT)

Australian Antarctic Division

203 Channel Highway

Kingston

Tasmania

7050

Australia

+61 3 6232 3244

+61 3 6232 3351 (facsimile)

Topic category

Biota
Oceans

Extent

Description: Temporal Coverage

Temporal extent

TimePeriod: 2001-02-08 2001-02-11

Title: Benthic diatom communities of coastal marine environments in the Windmill Islands, Antarctica

Date (Publication): 2003