Soft sediment assemblages at Casey Station: Spatial variation and human impacts. (core samples: Oct-Dec 1997)Entry ID: ASAC_2201_Casey_benthic_survey2
Abstract: A survey of macrobenthic assemblages in soft-sediments was done at Casey Station, East Antarctica. Samples were taken by divers using hand-held corers (core size - 10 cm diameter by 10 cm deep). The aims were: 1) To examine spatial variation at several scales in these assemblages; 2) To determine if there were differences between potentially impacted areas and control areas; 3) To determine the ... level of replication, taxonomic resolution and data transformation that are appropriate to studies of human impacts in Antarctic soft-sediment assemblages. Cores were collected by divers in a hierarchical, spatially nested design incorporating 4 scales: Locations (1000s of metres apart), Sites (100s of metres), Plots (10s of metres) and among replicates within plots (~1 metre). Four replicates for infaunal analysis were collected from each plot.
Variation at the whole assemblage level was most significant at the largest scale: between Locations; but significant differences were also found between Plots within Sites, and between Sites within Locations. The impacted locations, near two waste tips, a sewage outfall and a wharf, as a group were significantly different to control locations. Impacted locations had less variable assemblages but more variable populations of dominant species than control locations. Control locations had greater richness and diversity than impacted locations. Patterns of assemblage structure were similar at fine (species and family) and medium (family to order) levels of taxonomic resolution but changed at coarse (phylum) levels of resolution. Assemblage patterns were similar between untransformed, square root and fourth root transformations but often different in presence/absence transformations.
Concentrations of metals in sediments were also analaysed and other environmental variables such as grain size and water depth were measured (two replicates from each plot). Multivariate correlations between the biological and environmental datasets were examined.
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Start Date: 1997-10-22Stop Date: 1997-12-31
Vertical Resolution: 1 m
HUMAN DIMENSIONS > ENVIRONMENTAL IMPACTS > CONTAMINANT LEVELS/SPILLS
HUMAN DIMENSIONS > ENVIRONMENTAL IMPACTS > HEAVY METALS CONCENTRATION
HUMAN DIMENSIONS > ENVIRONMENTAL IMPACTS > SEWAGE DISPOSAL
OCEANS > MARINE ENVIRONMENT MONITORING > MARINE OBSTRUCTIONS
BIOLOGICAL CLASSIFICATION > ANIMALS/INVERTEBRATES
BIOLOGICAL CLASSIFICATION > ANIMALS/INVERTEBRATES > ARTHROPODS > CRUSTACEANS
BIOLOGICAL CLASSIFICATION > ANIMALS/INVERTEBRATES > ECHINODERMS
BIOLOGICAL CLASSIFICATION > ANIMALS/INVERTEBRATES > MOLLUSKS
BIOLOGICAL CLASSIFICATION > ANIMALS/INVERTEBRATES > SEGMENTED WORMS (ANNELIDS)
BIOSPHERE > AQUATIC ECOSYSTEMS > BENTHIC HABITAT
BIOSPHERE > AQUATIC ECOSYSTEMS > COASTAL HABITAT
BIOSPHERE > AQUATIC ECOSYSTEMS > MARINE HABITAT
BIOSPHERE > ECOLOGICAL DYNAMICS > SPECIES/POPULATION INTERACTIONS > POPULATION DYNAMICS
BIOSPHERE > ECOLOGICAL DYNAMICS > COMMUNITY DYNAMICS > SPECIES DOMINANCE INDICES
BIOSPHERE > ECOLOGICAL DYNAMICS > COMMUNITY DYNAMICS > COMMUNITY STRUCTURE
Quality Gammarid, Isopod, gastropod faunas identified at the Australian Museum. Remaining faunas identified by J. Stark.
Access Constraints Please contact investigators before using data.
Use Constraints This data set conforms to the PICCCBY Attribution License
May only be used if principal investigators acknowledged.
Data Set Progress
Distribution Media: HTTP
Distribution Size: 47 kb
Distribution Format: excel
Role: TECHNICAL CONTACT
Role: DIF AUTHOR
Phone: +44 (0117) 3314120
Email: Jo.Laybourn-Parry at bristol.ac.uk
University of Bristol School of Geographical Sciences University Road
Province or State: Bristol
Postal Code: BS8 1SS
Country: UNITED KINGDOM
Creation and Review Dates
DIF Creation Date: 2003-05-26
Last DIF Revision Date: 2010-12-14