IceCUBE (Coastal Underwater Benthic Ecosystems) is the umbrella name for our coastal marine research project that had its first field year in 2001/02. The project aims to better understand the structure and functioning of benthic (seafloor) ecosystems along the Ross Sea coast.

We are particularly interested in how seafloor communities are influenced by large-scale environmental drivers such as sea ice. This understanding will enable us to better predict the response of this unique ecosystem to environmental change.

Background

The coastal zone of the Ross Sea is one of the least modified on earth and offers unique opportunities to study natural ecosystems. The seafloor in this region contains an amazing diversity and density of organisms. These are often very slow-growing and long-lived, and their populations are therefore slow to recover from disturbance. The integrity of this region is potentially under threat from the increasing pressures of global climate change and other anthropogenic influences, such as fishing and tourism.

The Ross Sea coastline spans several degrees of latitude – from McMurdo Sound in the south, where Scott Base is situated (at around 77^oS), to Cape Adare in the north (at 72^oS). Environmental conditions vary along this latitudinal gradient and can influence seafloor communities. These include:

• water temperature
• disturbance by ice (including anchor ice and icebergs)
• sea ice (extent, persistence, and thickness)

For instance, sea ice conditions affect how much light is available for phytoplankton and other microscopic plants to grow. This affects the food supply for seafloor organisms.

The project

The goal of our Ross Sea research is to better understand the structure (what’s actually there – the diversity of organisms, ecosystems, and habitats) and function (how different species interact with each other and their habitat) of coastal seafloor communities. Our overarching hypothesis is that ice dynamics influence the structural and functional properties of coastal seafloor communities along the latitudinal gradient of the western Ross Sea coast.

We compare coastal seafloor ecosystems at different places along this coastline that differ in ice cover, light intensity, and circulation, and thus productivity (see graphic right). This will give us new information on links between animals and their environment, including feeding relationships.

Methods: Using dive surveys and remote video techniques, we conduct surveys of seafloor habitats and communities, and sample key organisms to determine their isotopic signatures (see below) and likley vulnerability to low-pH waters (a potential effect of climate change).

Location & timing: Various places along the Ross Sea coastline, from McMurdo Sound to Cape Adare (see map right). Our next field sampling is planned for late October 2008.

Applications: Understanding what makes these ecosystems tick will help us to better predict how they will respond to environmental change, such as that resulting from fisheries, tourism, and climate change (including ocean acificiation).

Links: This research is part of Antarctica New Zealand's Latitudinal Gradient Project (LGP),and is an International Polar Year (IPY) project (#1216 'Ross Sea coastal benthic ecosystems') within key IPY project #137 ‘Evolution and Biodiversity in the Antarctic’ (EBA).

NEW! This season (2009) we had NZ Royal Society Teacher Fellow Trisha Korth with us on the ice. See Trisha's impressions of Antarctic science on her WikiEducator site.

Funding: Foundation for Research, Science & Technology (IPY funding), NZ Ministry of Fisheries, and NIWA.

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Isotopic signatures

Stable isotopes are great tools for studying food web linkages, particularly in environments where simply sitting and watching interactions between organisms is not an option. Tissues of organisms contain carbon and nitrogen, which they get through their diet. Isotopic signatures of this carbon and nitrogen provides information about where in the food chain an organism sits. 

Further reading

Update from IceCUBE, Water & Atmosphere 16(1) 2008, p 4

Under the ice with Rod Budd, Water & Atmosphere 16(1) 2008, p 27

Sea ice effects on Ross Sea food webs, Aquatic Biodiversity & Biosecurity Update 26, Feb 2008

Life beneath the ice, Water & Atmosphere 13(3), 2005, pp 24-25

Assessing biodiversity on the Antarctic sea floor, Water & Atmosphere 11(3) 2003, pp 10-12

Life in the dark: plant growth beneath the sea ice, Water & Atmosphere 11(3) 2003, pp 14-15