Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Scientists find climate change to have paradoxical effects in coastal wetlands

Rising atmospheric carbon dioxide is largely responsible for recent global warming and the rise in sea levels. However, a team of scientists, including two Smithsonian ecologists, have found that this same increase in CO2 may ironically counterbalance some of its negative effects on one of the planet's most valuable ecosystems—wetlands. The team's findings are being published in the Proceedings of the National Academy of Sciences the week of March 23.

The team conducted their study for two years (2006 – 2007), during which they focused on the role that organic matter, both growing and decaying, plays on soil elevation in wetlands and the effect CO2 has on this process.

Coastal wetlands must build upward through the accumulation of mineral and organic matter to maintain a constant elevation relative to water levels; otherwise, they will drown and disappear. Climate change, however, is causing acceleration in the rise of sea level, which would seemingly put wetlands at risk of excessive flooding. "Our findings show that elevated CO2 stimulates plant productivity, particularly below ground, thereby boosting marsh surface elevation," said Adam Langley, the paper's lead author.

Patrick Megonigal, the paper's corresponding author, added "We found that by stimulating root growth, thus raising a marsh's soil elevation, elevated CO2 may also increase the capacity for coastal wetlands to tolerate relative rises in sea level." Both scientists are ecologists at the Smithsonian Environmental Research Center in Edgewater, Md.

These findings bear particular importance given the threat of accelerating sea-level rise to coastal wetlands worldwide. Some evidence suggests that only a two-millimeter increase in the rate of sea-level rise will threaten and possibly eliminate large portions of mid-Atlantic marshes. And the loss of these wetlands threatens critical services that the ecosystems provide, such as supporting commercially important fisheries, providing wildlife habitat, improving water quality and buffering human populations from oceanic forces.

Determining soil-surface elevation change is important for two reasons. First, the loss in soil elevation relative to local sea level may provide an early indication of the collapse of a tidal wetland. Second, tracking elevation changes in marsh soils through time, along with measurements of plant productivity and other environmental variables, allow scientists to identify specific mechanisms critical to the persistence of tidal wetlands under accelerating sea-level rise. To examine how CO2 may interact with other factors that will accompany sea-level rise, the authors also manipulated CO2, salinity and flooding in a companion greenhouse study.

The team of scientists from the Smithsonian Institution and the U.S. Geological Survey added CO2 gas to a tidal marsh at the Smithsonian Environmental Research Center. The gas flowed continuously from the bottom upward through the top of large (two-meter diameter) cylinders surrounding marsh plots. Half of the plots also received added soil nitrogen, simulating increasing water pollution, which tended to diminish the positive effects of elevated CO2 on marsh surface elevation. Changes in elevation were measured with an instrument developed by the U.S. Geological Survey that can detect changes in elevation as little as one millimeter. According to Langley, "Elevated CO2 doubled the short-term rate of elevation gain in our marsh. Our next step is to determine whether this will continue in the long-term and in the face of actual sea-level rise and other climatic changes."

Though marshes appear to benefit from CO2 in the short-term, the scientists stress that increasing CO2 levels will continue to warm the Earth, melt glaciers and expand ocean water, thus accelerating sea-level rise. Ultimately, rapidly rising seas could outstrip the positive effects of CO2 on the marshes that they have observed.

"Wetlands are some of the most specialized and valuable ecosystems in the world, not only to wildlife but humans as well," Megonigal said. "The sooner we can understand the effect global warming is having on them, the better we will be equipped to save them."

John Gibbons | EurekAlert!
Further information:

More articles from Ecology, The Environment and Conservation:

nachricht Invasive Insects Cost the World Billions Per Year
04.10.2016 | University of Adelaide

nachricht Malaysia's unique freshwater mussels in danger
27.09.2016 | The University of Nottingham Malaysia Campus

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

Im Focus: New Products - Highlights of COMPAMED 2016

COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.

In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...

Im Focus: Ultra-thin ferroelectric material for next-generation electronics

'Ferroelectric' materials can switch between different states of electrical polarization in response to an external electric field. This flexibility means they show promise for many applications, for example in electronic devices and computer memory. Current ferroelectric materials are highly valued for their thermal and chemical stability and rapid electro-mechanical responses, but creating a material that is scalable down to the tiny sizes needed for technologies like silicon-based semiconductors (Si-based CMOS) has proven challenging.

Now, Hiroshi Funakubo and co-workers at the Tokyo Institute of Technology, in collaboration with researchers across Japan, have conducted experiments to...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Resolving the mystery of preeclampsia

21.10.2016 | Health and Medicine

Stanford researchers create new special-purpose computer that may someday save us billions

21.10.2016 | Information Technology

From ancient fossils to future cars

21.10.2016 | Materials Sciences

More VideoLinks >>>