Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Pollution history documented through shell remains provides tool to study ecosystem change

29.03.2004


Without destroying endangered freshwater mussels



In the early 1900s, there were 42 species of freshwater mussels in the North Fork of the Holston River in Southwest Virginia. There were 33 downstream of Saltville. Now there are only nine species of mussels downstream of Saltville, and none directly below Saltville. When Virginia Tech geosciences student Megan Brown of Colonial Heights, Va., decided to study the local extinctions of these creatures, some of which have been known to live 200 years and many of which are endangered species, she didn’t want to have to use the traditional means of pulverizing them to measure chemical uptake.

At the joint meeting of the Northeastern and Southeastern Sections of the Geological Society of America, Brown will report on her non-invasive means to determine whether pollution or environmental stresses are threatening freshwater mussels. The GSA meeting is March 25-27 in Tysons Corner, Va.


Brown measured the mercury content in freshwater mussel shells in the river near Saltville, Va., where industry had polluted the river from 1950 until 1972, measured the damage done to the shells, and observed stages of recovery.

She looked at two sites upstream, unaffected by the pollution, at a site at Saltville, the point of the contamination, and at two sites downstream. "There was a very low level of mercury in shells upstream. I had to go 30 miles downstream to find a site with mercury levels at the background levels of the upstream sites," Brown says

Dead mussel shells reflected the levels of mercury, with high levels directly below Saltville and decreasing levels with increasing distance from Saltville. Brown examined shells to see if those from areas with no living populations looked different from shells in areas with living populations. She observed such characteristics as whether shells were still hinged together, external luster, edge preservation, and how broken they were.

"Wear could have been due to a change in stream gradient, but we found the most destruction was at the site of heaviest contamination and determined the heavy destruction was because there was no input of fresh-dead material," Brown says. "And wear was present whether the shell was thin or thick."

By documenting what happened to the mussels near Saltville, Brown has developed a strategy for study of other areas. "We can look at geochemical characteristics of the shell to determine what kind of pollution has impacted a system – to determine whether the local extinction is from pollution or an environmental stress such as heavy sedimentation," explains Brown. "And we can observe the kinds of destruction, such as the kinds of damage to shells, to help determine how long ago populations were still alive."

Brown will present the paper, "Using geochemical and taphonomic signatures of freshwater mussel shells to explore industry-related extirpations in the North Fork Holston River, Va. (60-8)," at 10:40 a.m. Saturday, March 27, in the Lord Thomas Fairfax Room of the Hilton McLean Tysons Corner. Co-authors are Virginia Tech geological sciences professor Michal Kowalewski, biology professor Donald Cherry, fisheries and wildlife professor Richard Neves, and geosciences professor Madeline Schreiber.

Brown, who received her undergraduate degree in biology from the University of Virginia, says she undertook the mussel study because "I’m interested in learning about the problems we’ve created and how we can remedy them." She expects to receive her master’s degree from Virginia Tech in May and would like to work with the Fish and Wildlife Service.

Susan Trulove | EurekAlert!
Further information:
http://www.technews.vt.edu/

More articles from Ecology, The Environment and Conservation:

nachricht Dispersal of Fish Eggs by Water Birds – Just a Myth?
19.02.2018 | Universität Basel

nachricht Removing fossil fuel subsidies will not reduce CO2 emissions as much as hoped
08.02.2018 | International Institute for Applied Systems Analysis (IIASA)

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: In best circles: First integrated circuit from self-assembled polymer

For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.

In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...

Im Focus: Demonstration of a single molecule piezoelectric effect

Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale

Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...

Im Focus: Hybrid optics bring color imaging using ultrathin metalenses into focus

For photographers and scientists, lenses are lifesavers. They reflect and refract light, making possible the imaging systems that drive discovery through the microscope and preserve history through cameras.

But today's glass-based lenses are bulky and resist miniaturization. Next-generation technologies, such as ultrathin cameras or tiny microscopes, require...

Im Focus: Stem cell divisions in the adult brain seen for the first time

Scientists from the University of Zurich have succeeded for the first time in tracking individual stem cells and their neuronal progeny over months within the intact adult brain. This study sheds light on how new neurons are produced throughout life.

The generation of new nerve cells was once thought to taper off at the end of embryonic development. However, recent research has shown that the adult brain...

Im Focus: Interference as a new method for cooling quantum devices

Theoretical physicists propose to use negative interference to control heat flow in quantum devices. Study published in Physical Review Letters

Quantum computer parts are sensitive and need to be cooled to very low temperatures. Their tiny size makes them particularly susceptible to a temperature...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

2nd International Conference on High Temperature Shape Memory Alloys (HTSMAs)

15.02.2018 | Event News

Aachen DC Grid Summit 2018

13.02.2018 | Event News

How Global Climate Policy Can Learn from the Energy Transition

12.02.2018 | Event News

 
Latest News

Researchers invent tiny, light-powered wires to modulate brain's electrical signals

21.02.2018 | Life Sciences

The “Holy Grail” of peptide chemistry: Making peptide active agents available orally

21.02.2018 | Life Sciences

Atomic structure of ultrasound material not what anyone expected

21.02.2018 | Materials Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>