IceCUBE - Antarctic coastal marine ecosystems

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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 understand the structure and functioning of Antarctic coastal benthic (seafloor) ecosystems, and better predict responses to future environmental change.

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, including warming and acidification.

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 77oS), to Cape Adare in the north (at 72oS). 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 spatial and temporal variation and trophic linkages [e.g., via isotopic signatures (see below)]. We also conduct experiments, both in the laboratory back in New Zealand, and in situ under the ice, to understand potential effects of future warming and ocean acidification on key species and on natural, intact ecosystems.

Read about ocean acification and warming

Location: Various places along the Ross Sea coastline, from McMurdo Sound to Cape Adare (see map right).

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.

Links: This research is part of Antarctica New Zealand's previous Latitudinal Gradient Project (LGP), and was an International Polar Year (IPY) project (#1216 'Ross Sea coastal benthic ecosystems') within key IPY project #137 ‘Evolution and Biodiversity in the Antarctic’ (EBA). It is currently linked to one of SCAR's new biology programmes, AnT-ERA (Antarctic Thresholds – Ecosystem Resilience and Adaptation).

In 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 

Current funding: Royal Society of New Zealand Marsden Fund 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

Page last updated: 
2 April 2014

IceCUBE - Antarctic coastal marine ecosystems : worms_200.jpg

A mass of nemertean (ribbon) worms, seastars, an ophiuroid (brittlestar), and a gastropod snail. Credit: Rod Budd, NIWA

IceCUBE - Antarctic coastal marine ecosystems : antarctic_food_200.jpg

A simplified view of the Ross Sea seafloor ecosystem during spring Credit: Vonda Cummings, NIWA

IceCUBE - Antarctic coastal marine ecosystems : ross_sea_map_200.jpg

The Ross Sea coastline. Credit: Brent Wood & Erika Mackay, NIWA