Skip to main content
ad info

 
CNN.com  nature
  Editions | myCNN | Video | Audio | Headline News Brief | Feedback  

 

  Search
 
 

 
NATURE
TOP STORIES

New hurdles hamper Galapagos oil spill cleanup

Insight, Prius lead the hybrid-powered fleet

Picture: Indonesia's Merapi volcano erupts

(MORE)

TOP STORIES

Up to 2,000 killed in India quake; fear of aftershocks spreads

Clinton aide denies reports of White House vandalism

New hurdles hamper Galapagos oil-spill cleanup

Two more Texas fugitives will contest extradition

(MORE)

MARKETS
4:30pm ET, 4/16
144.70
8257.60
3.71
1394.72
10.90
879.91
 


WORLD

U.S.

POLITICS

LAW

TECHNOLOGY

ENTERTAINMENT

HEALTH

TRAVEL

FOOD

ARTS & STYLE



(MORE HEADLINES)
*
  E-MAIL:
Subscribe to one of our news e-mail lists.
Enter your address:
Or:
Get a free e-mail account

 DISCUSSION:
 message boards
 chat
 feedback

  CNN WEB SITES:
CNN Websites
 AsiaNow
 En Español
 Em Português
 Svenska
 Norge
 Danmark
 Italian

 FASTER ACCESS:
 europe
 japan

 TIME INC. SITES:
 CNN NETWORKS:
Networks image
 more networks
 transcripts

 SITE INFO:
 help
 contents
 search
 ad info
 jobs

 WEB SERVICES:
CNN e-store


Age of Aquarius: Undersea lab immersed in coral reef research

Aquarius ENN



July 24, 2000
Web posted at: 3:56 p.m. EDT (1956 GMT)

They lived on the ocean floor for 10 days straight.

"You never see the sun and you never completely dry out," explained Karla Heidelberg, a lead scientist from the celebrated Aquarius mission that ended this week.

Operated by the University of North Carolina at Wilmington, Aquarius is the world's only undersea laboratory dedicated to science. Positioned near Key Largo in the Florida Keys National Marine Sanctuary, the lab is allowing scientists to monitor more closely and comprehensively life at the bottom of the sea.

With their base of operations set snugly on the ocean floor, researchers can dive for up to nine hours at a time. Surface dives, by comparison, usually last between one to two hours.

Aquarius researchers, or "aquanauts," conducted studies day and night, directly on coral reefs. For the first time, they evaluated all aspects of coral feeding in their natural habitat.

Prior to the Aquarius project, most research on coral reef diet was conducted in a laboratory "under unnatural conditions," Heidelberg said.

At least 30 different species of coral were examined on the Aquarius mission. In addition to filming coral feeding throughout the night, the aquanauts examined zooplankton abundance at multiple heights off the reef bottom to determine available prey. They also were able to characterize the fine-scale patterns of water flow around coral colonies.

diver
Experiments such as this coral feeding flume require continuous power for data transmission, supplied by cable from the Aquarius vessel  

Even at short distances, the rate of water flow over and around corals can change dramatically. This is significant because water motion plays a big role on coral biology, growth, competition, larval dispersal, fragmentation and sedimentation. Water motion also delivers prey to corals and enhances the exchange of nutrients, oxygen, and carbon dioxide.

"We focused on the basic biology of coral reefs, Heidelberg explained. "First we wanted to find out how many nutrients are available to the coral. Next, we wanted to see how the interaction between zooplankton and coral works.

"Coral reefs are unique systems that we know relatively little about. Ironically, scientists and legislatures are being asked to develop management guidelines to preserve these rapidly changing ecosystems before we fully understand the basic biology of reef ecosystems. As we learn more about the biology of the reefs, we will be better able to develop management guidelines that will protect our reefs."

The greatest impact of human activities on coral reefs are added nutrients caused by fertilizer, non-point source pollution, sedimentation from coastal development, forest destruction and sewage runoff from land, Heidelberg noted.

"Nutrients cause large algae blooms and increased particulate matter in the water column," she explained. "The added particulates filter out needed sunlight to the bottom and also clog coral feeding structures. The coral has to expend excess energy to remove the particles and consequently may have more difficulty feeding on zooplankton."

Coral reefs in the Florida Keys are particularly sensitive because of their location, Heidelberg said. "Florida reefs are at the northernmost extreme of where they can survive before the water gets too cold. Adding more stress could be enough to shift the ecosystem."

Copyright 2000, Environmental News Network, All Rights Reserved




RELATED STORIES:
Destructive, cloned algae drifts toward U.S. coast
July 7, 2000
Ships rerouted to protect marine sanctuaries
June 5, 2000
Pew floats marine commission to assess America's oceans
May 30, 2000
Fiji fouled by coral reef bleaching
April 26, 2000
Clinton unveils initiative to protect U.S. oceans and coasts
May 26, 2000
NOAA installs coral reef navigation aids
March 9, 1999

RELATED ENN STORIES:
Coral reef research (audio)
Saving Florida's coral reefs (audio)
Aquanauts set up camp on coral reef
Carbon dioxide has a choke hold on coral reefs
Pew floats marine commission to assess America's oceans

RELATED SITES:
Aquarius mission web site
Florida Keys National Marine Sanctuary


Note: Pages will open in a new browser window
External sites are not endorsed by CNN Interactive.

 Search   


Back to the top   © 2001 Cable News Network. All Rights Reserved.
Terms under which this service is provided to you.
Read our privacy guidelines.