Navigation Links
Glacial watersheds may contribute to oceanic food web
Date:12/23/2009

PORTLAND, Ore. December 23, 2009. A study recently completed in the gulf coast of Alaska by federal and university researchers has found that as glacial ice disappears, the production and export of high- quality food from glacial watersheds to marine ecosystems may disappear too. This trend could have serious consequences for marine food webs.

The study, "Glaciers as a source of ancient and labile organic matter to the marine environment," was recently published in the December 24, 2009, issue of the journal Nature.

The research, which was conducted on 11 coastal watersheds in the Gulf of Alaska, has documented an interesting paradox with important implications for coastal ecosystems. "Glacial watersheds comprise 30 percent of the Tongass National Forest and supply about 35 to 40 percent of the stream discharge," says Rick Edwards, a coauthor on the study. "These watersheds export dissolved organic matter that is remarkably biologically active in contrast to that found in other rivers. Generally, scientists expect that organic matter decreases in its quality as a food source as it ages, becoming less and less active over time."

But the dissolved organic material discharged from the glacial watersheds in this study was almost 4,000 years old; yet surprisingly, more than 66 percent of it was rapidly metabolized by marine microbes into living biomass to support marine food webs, adds Edwards.

The study was conducted by Eran Hood, University of Alaska Southeast; Jason Fellman, University of Alaska Fairbanks; Robert Spencer and Peter Hernes, University of California Davis; Rick Edwards and David D'Amore, Pacific Northwest (PNW) Research Station, USDA Forest Service; and Durelle Scott, Virginia Tech.

Edwards and D'Amore partnered with their university colleagues to characterize the dominant types of watersheds and variables that control the volume and chemistry of water flowing into the gulf. The study was led by Hood and Fellman, then a graduate student working in the PNW Research Station's Juneau Forestry Sciences Lab.

Rivers fringing the gulf coast of Alaska discharge as much water as the Mississippi River into a marine system that harbors the most productive salmon fishery in the world. As these rivers flow through the temperate rain forests on the coastal margin, they are influenced by vegetation, soils and wetlands, which control the amount and timing of carbon and nutrients delivered to the productive coastal ecosystems receiving that drainage.

"Understanding how these various watersheds respond to management activities and climate change is essential in mitigating the impacts of a warming climate on habitat quality within rivers and productivity within the adjacent marine ecosystem," explains Edwards.

"We don't currently have much information about how runoff from glaciers may be contributing to productivity in downstream marine ecosystems," said Hood. "This is a particularly critical question given the rate at which glaciers along the Gulf of Alaska are thinning and receding."

Highlights of the study include:

The greater the amount of glacier in the watershed, the older the dissolved organic matter and the more available it is to marine organisms.

These results support the hypotheses that microbial communities beneath the glaciers grow on soils and forests overrun by the glaciers during the Hypsithermal warm period (between 7,000-2,500 years ago). As they degrade the ancient material, they make new food from old carbon.

The quality of the dissolved organic matter is so high that 23 to 66 percent is used by marine micro-organisms and incorporated into food webs supporting higher organisms.

As glaciers recede and disappear, the input of this valuable food source will decrease with unknown impacts on productivity of marine food webs.


'/>"/>

Contact: Sherri Richardson Dodge
srichardsondodge@fs.fed.us
503-808-2137
USDA Forest Service, Pacific Northwest Research Station
Source:Eurekalert

Related biology news :

1. Searching for an interglacial on Greenland
2. Study: Did early climate impact divert a new glacial age?
3. A warming climate can support glacial ice
4. Study of agricultural watersheds and carbon losses
5. Study explores how life experiences contribute to the biological changes of Alzheimers
6. Scientists discover new genetic variation that contributes to diabetes
7. Cool new tools let public contribute to massive interactive online biodiversity encyclopedia
8. Hormone levels contribute to stress resilience
9. Work in mice will contribute to the study of hereditary diseases that lead to blindness
10. Temporary infidelity may contribute to the stability of ancient relationships
11. IFAR contributes to study that finds genes that influence the start of menstruation
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:3/24/2017)... Research and Markets has announced the addition of the ... Forecast to 2025" report to their offering. ... The Global Biometric Vehicle Access System ... over the next decade to reach approximately $1,580 million by 2025. ... forecasts for all the given segments on global as well as ...
(Date:3/23/2017)... 23, 2017 Research and Markets has announced ... & Trends - Industry Forecast to 2025" report to their ... The ... CAGR of around 8.8% over the next decade to reach approximately ... the market estimates and forecasts for all the given segments on ...
(Date:3/22/2017)... NEW YORK , March 21, 2017 /PRNewswire/ ... Customer Marketing Cloud used by retailers such as ... in its platform — Product Recommendations and Replenishment. Using ... to give more personalized product and replenishment recommendations ... purchases, but also on predictions of customer intent ...
Breaking Biology News(10 mins):
(Date:3/27/2017)... , March 27, 2017 DarioHealth Corp. (NASDAQ: ... health and big data solutions, today announced that it ... coverage option for U.S. consumers who want to have ... DarioHealth has signed strategic alliance agreements with partners across ... coverage benefits, and if approved, will supply and bill ...
(Date:3/24/2017)... Research and Markets has announced the addition of the "Human ... report to their offering. ... This report analyzes the Global market for Human Embryonic ... are provided for the period 2014 through 2022. Market data and ... The report profiles 25 companies including many key and niche players ...
(Date:3/24/2017)... , March 24, 2017 Agenus Inc. (NASDAQ: ... checkpoint antibodies and cancer vaccines, today announced participation at ... th  Annual William Blair and Maidstone Life Sciences conference ... Center in New York, NY . ... March 29 at 9:40 am: Robert B. Stein ...
(Date:3/23/2017)... , March 23, 2017  Northwest Biotherapeutics ... DCVax® personalized immune therapies for solid tumor cancers, ... $7.5 million financing it announced last Friday, March ... to several institutional investors securities totaling 28,843,692 shares, ... share, and 10,000,000 shares of Class C Warrants ...
Breaking Biology Technology: