Free Newsletters - Space - Defense - Environment - Energy - Solar - Nuclear
..
. Earth Science News .




ICE WORLD
Antarctic fjords are climate-sensitive hotspots of diversity in a rapidly warming region
by Staff Writers
Manoa HI (SPX) Dec 06, 2013


Andvord Bay, Antarctica, is a fjord hotspot of seafloor abundance and biodiversity, according to new research by the University of Hawaii at Manoa. Credit: Craig Smith, University of Hawaii at Manoa.

Deep inside the dramatic subpolar fjords of Antarctica, researchers from the University of Hawai'i at Manoa have discovered an unexpected abundance and diversity at the seafloor. During a recent expedition, UH scientists for the first time studied the seafloor communities of glacier dominated fjords along the west Antarctic Peninsula, a region undergoing very rapid climate warming.

The scientists expected to find impoverished seafloor communities highly disturbed by glacial sedimentation, similar to those that have been documented in well-studied Arctic regions. To their surprise, bristle worms, anemones, sea spiders, and amphipod crustaceans abounded in their seafloor photographs, along with a number of sea cucumbers, deep ocean jellyfish and other species. Above the seafloor, the fjord waters were dense with krill.

Scientists suggest that the differences in diversity and abundance between Arctic and Antarctic fjords can be explained by the fact that the subpolar Antarctic is in an earlier stage of climate warming than the Arctic, allowing the Antarctic fjords to sustain high levels of productivity. The Antarctic fjords show little disturbance from glacial melting.

"Our study area along the Antarctic Peninsula is warming as fast as anywhere in the world, and the amazing ecosystems there are changing very quickly," said Craig Smith, a professor of oceanography at UH Manoa who has been studying how marine ecosystems in the Antarctic are responding to climate warming.

"There appears to be something special about these fjords that stimulates seafloor productivity," said Laura Grange, a researcher at the National Oceanography Centre, University of Southampton, United Kingdom, who was a postdoctoral collaborator at UH Manoa with Smith during this study.

"Seafloor ecosystems at the bottom of fjords rely on detritus for food, so these Antarctic fjords must be getting some sort of enhanced food input, most likely from phytoplankton blooms, macroalgal debris, or even from krill-their molted carapaces or the dead bodies that sink to the bottom," Grange said.

Researchers have even suggested that large aggregations of humpback whales may stimulate fjord primary productivity by releasing nutrients as they feed and defecate in the fjords during seasonal immigration.

Even with a variety of pathways to fuel the remarkable diversity of animals on the seafloor, Antarctic fjord ecosystems are at risk from climate warming.

In today's Antarctica, fjord glaciers currently sustain very little melting and the icebergs they shed drift out to sea without dropping much sediment - scientists say these fjords have "weak meltwater influence." As a result, fjord headwaters are clear of suspended sediments, allowing phytoplankton and benthic algae to bloom, and producing little burial disturbance of rich seafloor fauna.

These favorable conditions are very likely to change as the climate warms rapidly, accelerating glacial melting and dumping large amounts of fine glacial sediments into fjord headwaters.

The resulting higher turbidity and seafloor sedimentation will likely shade the phytoplankton and bury diverse seafloor communities, or smother primary production and biodiversity in these narrow canyon-like ecosystems.

"The extraordinary ecosystems, which provide habitat and foraging areas for krill and baleen whales and are hotspots of seafloor diversity, are very likely to be negatively impacted by the very rapid climate warming occurring along the Antarctic Peninsula," Smith said.

"The fjords also happen to be the focus of Antarctic ecotourism, with thousands of visitors on cruise ships each year entering the fjords to view penguins and whales and to experience the sheer abundance and diversity of Antarctic life. Climate warming may thus dramatically change some of the most iconic of Antarctic ecosystems."

"These Antarctic fjord ecosystems may play a disproportionately large role in feeding and recruiting of mobile species, including juvenile fish and whales," Smith said. "We urgently need to develop a better understanding of the structure, function, and climate sensitivity of these fascinating and imperiled seafloor communities."

Laura J. Grange and Craig R. Smith. PLOS ONE.

.


Related Links
University of Hawaii at Manoa
Beyond the Ice Age






Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle




Memory Foam Mattress Review
Newsletters :: SpaceDaily :: SpaceWar :: TerraDaily :: Energy Daily
XML Feeds :: Space News :: Earth News :: War News :: Solar Energy News





ICE WORLD
'Tiger stripes' underneath Antarctic glaciers slow the flow
Princeton NJ (SPX) Nov 11, 2013
Narrow stripes of dirt and rock beneath massive Antarctic glaciers create friction zones that slow the flow of ice toward the sea, researchers at Princeton University and the British Antarctic Survey have found. Understanding how these high-friction regions form and subside could help researchers understand how the flow of these glaciers responds to a warming climate. Just as no-slip strip ... read more


ICE WORLD
Millions of lives at risk as governments fail to adopt disaster warning system

Late treatment for many Philippine typhoon victims: WHO

Human trafficking a worry in post-typhoon Philippines: US

China graft investigation into ex-head of quake city

ICE WORLD
Cloud firm Box raises $100 mn

Laser Communication Mission Targets 2017 Launch

New Effect Couples Electricity and Magnetism in Materials

Satellite Cooling System Breakthrough Developed by Lockheed Martin Space Systems

ICE WORLD
Scripps Leads First Global Snapshot of Key Coral Reef Fishes

Silent stalkers of dark ocean waters

Rising Ocean Acidification Leads to Anxiety in Fish

Sea-level rise to drive coastal flooding, regardless of changes in hurricane activity

ICE WORLD
Antarctic fjords are climate-sensitive hotspots of diversity in a rapidly warming region

Rainfall to blame for decline in Arctic peregrines

Glaciers sizzle as they disappear into warmer water

Subarctic lakes are drying up at a rate not seen in 200 years

ICE WORLD
How onions recognize when to bulb

Benefit of bees even bigger than thought: food study

Romania sees opportunity in China's new taste for meat

Flower Power - Researchers breed new varieties of chamomile

ICE WORLD
Slippery clay intensified Japan 2011 tsunami-quake: scientists

Malaysia floods force more evacuations as 1 more dead

One dead, 19,000 evacuated in Malaysia floods

NASA's HS3 Hurricane Mission Called it a Wrap for 2013

ICE WORLD
US praises French 'leadership' in C. Africa conflict

France tells Africa to take charge of security

France looks to recast Africa role at summit

Mali defence minister vows to support coup leader's trial

ICE WORLD
Evidence of funerary meal found at 13,000-year-old gravesite in Israel

Skull find shows women were sacrificed in ancient China

Study suggests inbreeding shaped course of early human evolution

Investments in Aging Biology Research will Pay Longevity Dividend




The content herein, unless otherwise known to be public domain, are Copyright 1995-2014 - Space Media Network. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA Portal Reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement