Though water and electricity are not usually a good mix, the combination is one of the best methods for collecting fish and determining their health. The electricity stuns them long enough to allow them to be scooped up in long nets, measured and tossed back.
“The integrity of the Center Hill Dam has been compromised and as the engineers fix it, everything downstream is changing and people want to know about it,” said Phil Bettoli, the primary investigator of the project and assistant leader of the U.S. Geological Survey’s Cooperative Fishery Research Unit, a joint effort between TTU, USGS, the U.S. Fish and Wildlife Service and the Tennessee Wildlife Resources Agency.
“The Army Corps of Engineers hired us to do the assessment of what is going on in that fish community now, but when they finish their repairs to the dam, they may go back to the way they used to operate the dam which is going to change the fish community again. We want to be able to predict what’s going to happen then.”
As engineers pump concrete into areas where the water has eroded the limestone into which the dam was built, a team of TTU researchers is collecting fish on the river at five locations below the dam. They have been there for two years and will be there for the next year and a half, working with two grants worth nearly $300,000 from the Army Corps of Engineers.
In the nearly four years that the dam repair has been underway, the biologists have found that the ecosystem has gotten healthier. The engineers have used a small gate that releases water and also aerates it at the same time, providing more dissolved oxygen for the fish and insects in the river. Also, water is being released on a more regular basis to lessen pressure on the structure, which provides a more consistent environment for the organisms living downstream.
“The dam was built for two main reasons; for electricity and flood control,” Bettoli, who is also a professor of biology at TTU, said. “They didn’t think about wildlife habitats in the 1940s when they built this. Now, you can’t ignore it.”
Researchers from a team of more than a dozen undergraduate and graduate students can be found on the river during all four seasons, at all times of the day. They are found either in a small flat-bottomed boat equipped with a small generator and long probes that run an electric current through the water, or wading through the river themselves with packs that generate electricity on their backs, nets in hand.
“I wanted this job because a lot of rivers are having the same issues the Caney Fork is,” said Tomas Ivasauskas, a TTU graduate who is working on the project. “If the engineers weren’t pumping the concrete in, the whole dam would have been compromised.”
Once the study is complete, their work will also provide a baseline of information for dam operators, as well as the TWRA, which manages a popular trout fishery on the river and the U.S. Fish and Wildlife Service, which is interested in the impact of the work on the Cumberland River and its endangered mussel populations. With the knowledge, they will be able to monitor the effects of the dam on the river and change their operations, if necessary.
Nearing the end of the first two-year grant, the team is getting ready to present its research. Studying fish populations below dams is difficult because researchers must alter their schedules to work around the various times the dam is generating power. Biologists also tend to consider dammed rivers to be artificial ecosystems; many native species are often killed off when a dam is built and other, nonnative species move in.
“There’s not a whole lot of this kind of work going on in North America under large hydroelectric dams,” Bettoli said. “The thinking was that people were not interested in the biotic integrity of radically altered systems. We expect a lot of questions and interest from our peers.”
Lori Shull | Newswise Science News
Successful calculation of human and natural influence on cloud formation
04.11.2016 | Goethe-Universität Frankfurt am Main
Invasive Insects Cost the World Billions Per Year
04.10.2016 | University of Adelaide
In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.
Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...
Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...
A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.
Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...
In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.
“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...
The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.
The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...
16.11.2016 | Event News
01.11.2016 | Event News
14.10.2016 | Event News
07.12.2016 | Health and Medicine
07.12.2016 | Life Sciences
07.12.2016 | Health and Medicine