Featured Research

from universities, journals, and other organizations

Scientists Study Georgia Salt Marsh To Understand Global Warming

Date:
June 10, 1998
Source:
Georgia Tech
Summary:
An interdisciplinary team of scientists has found a surprisingly high rate of carbon and nutrient turnover by microbes in one of Georgia's coastal salt marshes, a highly productive ecosystem.

An interdisciplinary team of scientists has found a surprisingly high rate of carbon and nutrient turnover by microbes in one of Georgia's coastal salt marshes, a highly productive ecosystem.

The team of researchers, all associated with the Georgia Institute of Technology, is conducting a long-term study at Sapelo Island, Ga., to examine the marsh's biogeochemical processes — that is, the exchange of biogeochemical elements such as carbon, phosphorus, nutrients and metals between living and non-living components of the environment. They want to know how these processes relate to the productivity, faunal activity and hydrology of the marsh system. An understanding of these relationships is crucial to predicting the effects of global warming on the coastal environment.

They are presenting their findings to date at the joint meeting of the Ecological Society of America and the American Society of Limnology and Oceanography to be held June 7 -12 in St. Louis, Mo. This presentation is scheduled for 11:30 a.m. June 11 in the conference facilities at the Adam's Mark Hotel.

"We observed some of the highest rates of organic matter decomposition ever measured in marine systems," said Dr. Joel Kostka, a Georgia Tech adjunct assistant professor and a researcher at the Skidaway Institute of Oceanography, a research unit of the University System of Georgia. One reason for the higher than expected results may have been the length of time the study was conducted; very few studies have looked at decomposition rates by microorganisms over a two-year period, as this ongoing study has done, Kostka added.

Researchers believe microorganisms in salt marsh sediments play a significant role in the cycling of materials in the ecosystem. By examining microorganisms, such as bacteria that occur in salt marsh sediments, the scientists hope to determine what drives microbial activity. By looking at the marsh environment across several seasons, they are learning how the nutrients flow through the system.

Numerous variables affect microbial activity in the sediments, said Dr. Philippe Van Cappellen, an associate professor in Georgia Tech's School of Earth and Atmospheric Sciences. He and Tech graduate student Alakendra Roychoudhury are working with Kostka on this study. Those variables include temperature, inundation by the tides, plant composition in the area, the hydrology of the area, the input of organic material, runoff from the adjoining land area and the mixing of the sediment.

Along with the microorganisms, larger forms of animal life also affect nutrient cycling in the marsh. Large populations of fiddler crabs that inhabit the mud flats in the salt marsh can greatly enhance nutrient cycles in the area, Kostka said. Their burrows, which can extend 20 centimeters into the soil, allow saltwater to infiltrate the mud, which in turn introduces oxygen and other nutrients into the sediments.

"The injection of oxygen changes microbial activity," Kostka said, "and that affects chemical and nutrient release."

Sapelo's salt marshes provide an ideal model system in which to study biogeochemical cycling in the environment, Van Cappellen said. Stretching along the eastern coast of North America from Nova Scotia to Florida, salt marshes are not only extensive, he said, but also extremely productive.

Here, great expanses of Spartina, or cord grass, form the basis of the food chain. Salt marshes play a critical role as nursery grounds for fishes, shellfish and other marine organisms by providing a place where the young stages of animals can grow rapidly.

The 10-acre Sapelo study site also provided another advantage to the research team; years of research have been conducted at the site and, hence, a great deal is already known about the dynamics of the ecosystem. The study represents a major departure from the typical approach to studying salt marshes, which is traditionally ecology based, according to the researchers.

With the introduction of biogeochemists, oceanographers and microbiologists, the researchers were able to gather more quantitative data that will help them better understand the factors controlling the cycling of these vital materials in salt marsh sediments.

"Clearly, not enough interdisciplinary studies have been done," Kostka said, referring to the value of the study and its many contributors. The research, which was funded by Georgia Tech's School of Earth and Atmospheric Sciences, the Georgia Sea Grant College program, the Office of Naval Research, the Skidaway Institute of Oceanography and the National Science Foundation through an initiative aimed at encouraging interdisciplinary studies, takes a different look at the dynamics of an important natural system.

The utility of the data being collected can be expanded well beyond the particular habitat at Sapelo where the study is under way. The researchers point out that the knowledge gained about the salt marsh can be extended to other natural systems. Such information will be useful as scientists grapple with the problems associated with global warming, Van Cappellen said.

"If sea levels rise with global warming, we need to understand the stability of these environments and determine if we will lose them," he said. With an increased knowledge of the biogeochemical cycles at work, humans can better predict the future of these dynamic and important areas, he added.


Story Source:

The above story is based on materials provided by Georgia Tech. Note: Materials may be edited for content and length.


Cite This Page:

Georgia Tech. "Scientists Study Georgia Salt Marsh To Understand Global Warming." ScienceDaily. ScienceDaily, 10 June 1998. <www.sciencedaily.com/releases/1998/06/980610082457.htm>.
Georgia Tech. (1998, June 10). Scientists Study Georgia Salt Marsh To Understand Global Warming. ScienceDaily. Retrieved July 24, 2014 from www.sciencedaily.com/releases/1998/06/980610082457.htm
Georgia Tech. "Scientists Study Georgia Salt Marsh To Understand Global Warming." ScienceDaily. www.sciencedaily.com/releases/1998/06/980610082457.htm (accessed July 24, 2014).

Share This




More Earth & Climate News

Thursday, July 24, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Goma Cheese Brings Whiff of New Hope to DRC

Goma Cheese Brings Whiff of New Hope to DRC

Reuters - Business Video Online (July 24, 2014) The eastern region of the Democratic Republic of Congo, mainly known for conflict and instability, is an unlikely place for the production of fine cheese. But a farm in the village of Masisi, in North Kivu is slowly transforming perceptions of the area. Known simply as Goma cheese, the Congolese version of Dutch gouda has gained popularity through out the region. Ciara Sutton reports. Video provided by Reuters
Powered by NewsLook.com
Higgins Breaks Record at Mt. Washington

Higgins Breaks Record at Mt. Washington

Driving Sports (July 24, 2014) Subaru Rally Team USA drivers David Higgins and Travis Pastrana face off against a global contingent of racers at the annual Mt. Washington Hillclimb in New Hampshire. Includes exclusive in-car footage from Higgins' record attempt. Video provided by Driving Sports
Powered by NewsLook.com
Storm Kills Three, Injures 20 at Virginia Campground

Storm Kills Three, Injures 20 at Virginia Campground

Reuters - US Online Video (July 24, 2014) A likely tornado tears through an eastern Virginia campground, killing three and injuring at least 20. Linda So reports. Video provided by Reuters
Powered by NewsLook.com
Creative Makeovers for Ugly Cellphone Towers

Creative Makeovers for Ugly Cellphone Towers

AP (July 24, 2014) Mobile phone companies and communities across the country are going to new lengths to disguise those unsightly cellphone towers. From a church bell tower to a flagpole, even a pencil, some towers are trying to make a point. (July 24) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

    Health News

      Environment News

        Technology News



          Save/Print:
          Share:

          Free Subscriptions


          Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

          Get Social & Mobile


          Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

          Have Feedback?


          Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
          Mobile: iPhone Android Web
          Follow: Facebook Twitter Google+
          Subscribe: RSS Feeds Email Newsletters
          Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins