[Parameters: Topic='OCEANS', Term='OCEAN OPTICS', Variable_Level_1='PHOTOSYNTHETICALLY ACTIVE RADIATION']
The structural and functional diversity of the shallow-water benthic community at Cape EvansEntry ID: K082_2001_2002_NZ_1
Abstract: The biodiversity of the seafloor community at Cape Evans was investigated to determine the structural and functional diversity of the benthic community and resurveyed over several seasons to assess year to year variability (01-09). A minimum of three sites, separated by at least 50m and accessed through separate dive holes were surveyed. Two 20m transect lines were laid on the seafloor within the ... 15-25m depth stratum starting from haphazardly chosen starting points. The transects were videoed using a diver-held digital video camera at a fixed height of (a) 70cm above the bottom (for the broader scale analysis of habitat structure) and (b) 40cm above the bottom (to allow for more accurate species identifications). Along one of the 20m transects, core samples were collected from five randomly chosen positions. At each position, two small sediment cores (20mm diam., 50mm deep) were collected, one to determine sediment grain size and benthic chlorophyll a content and one to determine the natural stable isotope signature of the sediment. Also at each position, one large core (70mm diam., 100mm deep) was collected to estimate the abundance and diversity of the benthic macrofauna. Additional collections include: a) three surface sediment scrapes to determine the species composition of microalgae, b) three individuals of each of the numerically dominant epibenthic species, for growth measurements and to determine the stable istope signatures and c) additional specimens of animals and plants and organic material (eg seal gaeces) for isotopic analysis to provide a more complete picture of the trophic structure of the community. Algae on the undersurface of the sea-ice were sampled to determine their isotopic signature using five small cores (20mm diam., 100mm deep). Another 9 cores were obtained for the determination of chlorophyll a and species composition of sea-ice algae. Video sampling was stratified by habitat and additional footage was taken of biota in the study area for a general picture of the site. Physical background variables (sea-ice conditions, light colour and intensity) were measured at 15m depth and water currents estimated. In the 03-04 season sediment traps, fluorometers and light meters were installed between depths of 15-25m. The sediment trap arrays were deployed at depths of 15, 20 and 25m. Each array consisted of three replicate tubes which were recovered the following season and analysed for algal species composition, relative abundance, total biomass and pigments to ascertain the relative contribution of phytoplankton and ice-algae as potential food sources for benthic invertebrates. Additional samples of ice algae were collected to compare and add to the list of ice algae taxa. The fluorometer were installed to measure temperature and water column chlorophyll fluorescence. It was deployed at 20m depth and programmed to measured phytoplankton chlorophyll fluorescence every two hours. Light sensors and data loggers were installed to record changes in photosynthetically available radiation (PAR). In the 04-05 season, sea urchins Sterechinus neumayeri were collected over a range of depths and analysed gut contents and size-frequency. In all seasons, the site was resurveyed using the above diver-held video camera. The site was resurveyed in the 2005-06 and the 2008-09 field seasons.
This data set description is a member of a collection. The collection is described in
Start Date: 2001-11-06Stop Date: 2008-11-19
OCEANS > OCEAN OPTICS > FLUORESCENCE
OCEANS > OCEAN OPTICS > PHOTOSYNTHETICALLY ACTIVE RADIATION
BIOLOGICAL CLASSIFICATION > ANIMALS/INVERTEBRATES
BIOLOGICAL CLASSIFICATION > PLANTS
OCEANS > OCEAN CHEMISTRY > PIGMENTS > CHLOROPHYLL
BIOSPHERE > AQUATIC ECOSYSTEMS > BENTHIC HABITAT
BIOSPHERE > AQUATIC ECOSYSTEMS > COASTAL HABITAT
BIOSPHERE > ECOLOGICAL DYNAMICS > COMMUNITY DYNAMICS > COMMUNITY STRUCTURE
Data Set Progress
Phone: +64 7 856 7026
Fax: +64 7 856 0151
Email: v.cummings at niwa.co.nz
NIWA PO Box 11-115
Country: New Zealand
Role: DIF AUTHOR
Phone: +64 3 358 0200
Fax: +64 3 358 0211
Email: s.gordon at antarcticanz.govt.nz
Antarctica New Zealand Private Bag 4745
Country: New Zealand
Thrush, S.F., Hewitt, J.E., Cummings, V.J., Norkko, A. And Chiantore, M. 2010. ß-Diversity and species accumulation in Antarctic coastal benthos: Influence of habitat, distance and productivity on ecological connectivity. PLOS One 5(7): e11899 doi:10.1371/journal.pone.0011899
Norkko, A. Thrush, S.F. Cummings, V.J. Funnell, G.A. Schwarz, A.-M. Andrew, N.L. Hawes, I. Ecological role of ... Phyllophra antarctica drift accumulations in coastal soft-sediment communities of McMurdo Sound, Antarctica. Polar biology 27: 482-494, 2004.
Cummings, V.J. 2003. Assessing biodiversity on the Antarctic sea floor. Water and atmosphere 11(3): 10-12, 2003.
Norkko, J. Indicators of short-term growth in bivalves: detecting environmental change across ecological scales. Ph.D., University of Auckland : . 2005.
Norkko, A. Thrush, S.F. Cummings, V.J. Gibbs, M.M. Andrew, N.L. Norkko, J. Schwarz, A-M. Trophic structure of coastal Antarctic food webs associated with changes in sea ice and food supply. Ecology 88: 2810-2820, 2007.
Schwarz, A.-M. 2003. Life in the dark: plant growth beneath the sea ice. Water and atmosphere 11(3): 14-15, 2003.
Schwarz, A.-M. Hawes, I. Andrew, N. Mercer, S. Cummings, V. Thrush, S. Primary production potential of non-geniculate coralline algae at Cape Evans, Ross Sea, Antarctica. Marine ecology progress series 294: 131-140, 2005.
Thrush, S. Dayton, P. Cattaneo-Vietti, R. Chiantore, M. Cummings, V. Andrew, N. Hawes, I. Kim, S. Kvitek, R. Schwarz, A.-M. Broad-scale factors influencing the biodiversity of coastal benthic communities of the Ross Sea. Deep-sea research II 53: 959-971, 2006.
Norkko, J. Norkko, A. Thrush, S.F. Cummings, V.J. Detecting growth under environmental extremes: Spatial and temporal patterns in nucleic acid ratios in two Antarctic bivalves. Journal of experimental marine biology and ecology 326: 144-156, 2005.
Schwarz, A-M. Hawes, I. Andrew, N. Norkko, A. Cummings, V. Thrush, S. 2003 Macroalgal photosynthesis near southern global limit for growth; Cape Evans, Ross Sea, Antarctica. Polar biology 26: 789-799
Cummings, V.J., Thrush, S.F., Norkko, A., Andrew, N.L., Hewitt, J.E., Funnell, G.A., Schwarz, A-M. 2006. Accounting for local scale variability in benthos: implications for future assessments of latitudinal trends in the coastal Ross Sea. Antarctic Science 18(4): 633-644.
Creation and Review Dates
DIF Creation Date: 2005-10-11
Last DIF Revision Date: 2010-12-08