Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Eastern US water supplies threatened by a legacy of acid rain

27.08.2013
Human activities are changing the water chemistry of many streams and rivers in the Eastern U.S., with consequences for water supplies and aquatic life, so reports a new study in the journal Environmental Science and Technology.

In the first survey of its kind, researchers looked at long-term alkalinity trends in 97 streams and rivers from Florida to New Hampshire. Sites ranged from small headwater streams to some of the nation's largest rivers. Over the past 25 to 60 years, two-thirds have become significantly more alkaline.


Alkalinity trends were observed in large rivers like the Potomac River as well as small streams located in urbanized watersheds, such as the Gwynns Falls in Baltimore, Md.

Credit: Steward T.A. Pickett, Baltimore Ecosystem Study LTER

Alkalinity is a measure of water's ability to neutralize acid. In excess, it can cause ammonia toxicity and algal blooms, altering water quality and harming aquatic life. Increasing alkalinity hardens drinking water, causing pipe scaling and costly infrastructure problems. And, perhaps most alarming, it exacerbates the salinization of fresh water.

In what may seem like a paradox, human activities that create acid conditions are driving the problem. This is because acid rain, acidic mining waste, and agricultural fertilizers speed the breakdown of limestone, other carbonate rocks, and even concrete and cement. The result: alkaline particles are washed off of the landscape and into streams and rivers.

The survey found watershed geology was the strongest predictor of river alkalinization, with rivers receiving water from porous, limestone, and other carbonate rocks being more alkaline. Topography and pollution were also triggers. The most rapid rates of alkalinization were at high elevation sites that were chronically exposed to acid pollution.

Among the rivers impacted by higher alkalinity are those that provide water for Washington, D.C., Philadelphia, Baltimore, Atlanta, and other major cities, the researchers reported. This is due, in part, to acid rain exposure, urbanization, and the extent of land covered by cement and concrete.

Also affected are rivers that flow into water bodies already harmed by excess algae, such as the Chesapeake Bay, where managers are struggling to contain algal blooms that are toxic to fish, oysters, and crabs. Appalachian Mountain streams are also vulnerable. In that region, thin soils and steep slopes cause erosion, and there is persistent exposure to industry emissions.

Noted ecologist Gene Likens, Founding Director of the Cary Institute of Ecosystem Studies and a co-discoverer of acid rain, was among the study's authors. The extent of alkalinity change in streams and rivers exceeded his expectations: "This is another example of the widespread impact humans are having on natural systems. Policymakers and the public think that the acid rain problem has gone away, but it has not."

Adding, "Acid rain has led to increased outputs of alkalinity from watersheds and contributed to long-term, increasing trends in our rivers. And this is twenty years after federal regulations were enacted to reduce the airborne pollutants that cause acid rain."

Lead author Sujay Kaushal, an associate professor and aquatic ecologist at the University of Maryland, notes, "What we are seeing may be a legacy effect of more than five decades of pollution. These systems haven't recovered. Lagging effects of river alkalinization are showing up across a major region of the U.S. How many decades will it persist? We really don't know the answer."

The research was funded by NASA Carbon Cycle & Ecosystems, the National Science Foundation's Long Term Ecological Research Program, and The Andrew W. Mellon Foundation.

Sujay S. Kaushal, Gene E. Likens, Ryan M. Utz, Michael L. Pace, Melissa Grese, and Metthea Yepsen, "Increased river alkalization in the Eastern U.S," in Environmental Science and Technology, August 26, 2013. View the article at: http://pubs.acs.org/doi/abs/10.1021/es401046s

The full research team included:
Sujay S. Kaushal, University of Maryland, College Park
Gene E. Likens, Cary Institute of Ecosystem Studies & University of Connecticut
Ryan M. Utz, National Ecological Observatory Network
Michael L. Pace, University of Virginia
Melissa Grese, University of Maryland, College Park
Metthea Yepsen, University of Maryland, College Park
The Cary Institute of Ecosystem Studies is a private, not-for-profit environmental research and education organization in Millbrook, N.Y. For nearly thirty years, Cary Institute scientists have been investigating the complex interactions that govern the natural world. Their objective findings lead to more effective policy decisions and increased environmental literacy. Areas of expertise include air and water pollution, climate change, invasive species, and the ecological dimensions of infectious disease. Learn more at http://www.caryinstitute.org

Lori Quillen | EurekAlert!
Further information:
http://www.caryinstitute.org

More articles from Ecology, The Environment and Conservation:

nachricht Upcycling 'fast fashion' to reduce waste and pollution
03.04.2017 | American Chemical Society

nachricht Litter is present throughout the world’s oceans: 1,220 species affected
27.03.2017 | Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung

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: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

7th International Conference on Crystalline Silicon Photovoltaics in Freiburg on April 3-5, 2017

03.04.2017 | Event News

 
Latest News

Bare bones: Making bones transparent

27.04.2017 | Life Sciences

Study offers new theoretical approach to describing non-equilibrium phase transitions

27.04.2017 | Physics and Astronomy

From volcano's slope, NASA instrument looks sky high and to the future

27.04.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>