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November 15, 2013
CONTACT: K.E. Schwab

Researchers monitor stream algae news

SLIPPERY ROCK, Pa. - Algae, those single or multi-cellular photosynthetic organisms frequently seen attached to aquarium walls, are talking to Slippery Rock University researchers, and the green organisms are telling them about the state of recovery in parts of Slippery Rock Creek.

Dean DeNicola, an SRU biology professor and his student researchers, are primarily examining benthic algae, the kind that grows on rocks on the bottom of streams. The streams in their research are in the headwaters of nearby Slippery Rock Creek, and they are contaminated by water coming out of abandoned mines frequently called "acid mine drainage or AMD."

"In streams that receive significant impacts from mining the algae are not very plentiful, which is not good for the environment and aquatic life, since algae is one of the main energy sources at the base of the food chain," he said. "Algae are an excellent indicator of the pH, acid or base, and environmental conditions of the streams. As a result benthic algal communities are used as indicators in streams because they are highly responsive to habitat change, such as disruption of the ecosystem due to acid mine drainage," DeNicola said. In addition, algae require nitrogen and phosphorus as two critical nutrients for their growth, but the mine water reduces those nutrients.

"AMD occurs when minerals associated with coal deposits are exposed to air and water in what are now abandoned mines. This creates a series of chemical reactions that results in mine water discharges that are high in acidity with high concentrations of metals. AMD runoff into streams drastically reduces the abundance and diversity of stream organisms. AMD affects one-third of the stream miles in Pennsylvania, and is the major water quality problem in Appalachian watersheds," he said. Newer laws passed in 1977 prohibit coal operators from allowing such runoff, but for the vast number of long-abandoned mines the laws are of little use.

Amber Lellock, an SRU biology major from Punxsutawney, said, "Working on this research project provided me with an opportunity I never envisioned myself having, and I consider myself quite lucky. I thoroughly enjoyed the fieldwork and first-hand experience. It isn't like being in a classroom with 20 or so students; rather I had the chance to learn new techniques and utilize them almost instantaneously."

"Millions of years ago, when the dinosaurs where here and Pennsylvania was a tropical swamp, coal was formed from the dead plant matter. As long as the minerals in ground containing heavy metals remained in an environment with no oxygen they were not a problem. When the mines were opened to remove the coal, the minerals were exposed to oxygen forming acids and releasing metals to create an ecological problem," he said. "The Slippery Rock Creek Watershed has been severely impacted by AMD for more than a century, predominantly from coal mining activities in a 27-square-mile area at the headwaters of the stream, near Boyers" he said.

The AMD discharges in the headwaters have been inventoried and targeted for restoration by the Slippery Rock Watershed Coalition, whose members represent Slippery Rock University, Pennsylvania state agencies, nonprofit organizations, private environmental consulting firms and the local community. The treatment of the AMD discharges in the headwater area of Slippery Rock Creek uses recent technology that included installation of 12 passive treatment systems.

The passive treatment systems for AMD are relatively inexpensive to build, require only natural materials - limestone - and gravity and last 20 to 50 years with minimum maintenance, DeNicola said.

When correctly designed for the flow rate and chemistry of the discharge, passive treatment systems have been shown to be extremely effective in improving water quality of the AMD sources, and this new technology has been pioneered by people working on the Slippery Rock Creek project.

However, despite a large economic investment related to the increasing use of passive treatment technology to restore streams affected by AMD, studies examining long-term biological recovery of the stream ecosystem are scarce, which is why the SRU contingent undertook the research project, DeNicola said.

The SRU program began in 1995 as DeNicola and his students began research looking at the stream recovery process. The team has collaborated with Michael Stapleton, associate professor of geography, geology and the environment, to monitor the biological recovery of tributaries in the headwaters of Slippery Rock Creek that have received passive treatment systems.

Additionally, a number of short-term studies have also resulted over the years related to the larger research project.

"Students collect and analyze invertebrate, algal and water chemistry data from the streams receiving treatment. Approximately 30 students have worked on these projects over the years," DeNicola said.

Students involved in the projects have presented their findings at the annual Slippery Rock Watershed Symposium on acid mine drainage at Jennings Environmental Center, the Sigma Xi Research Undergraduate Research Conference, and the SRU Research Symposium, and have summarized their findings in reports and peer-reviewed publications.

"In today's job market, the competition is high. Not only did I have fun working on this research project, but I believe that my involvement will benefit my career search," she said.

"Dr. DeNicola is a great adviser, and I thank him for all his expertise and patience. I am proud to attend Slippery Rock University where I am part of undergraduate research that I am passionate about and will use in the future," Lellock said.

She will be presenting her findings from the project at the Pennsylvania State System of Higher Education Science, Technology, Engineering and Mathematics Conference being hosted at SRU's Smith Student Center today and Nov. 16.

More than 120 students from across the state system, including 47 from SRU, will present research at the conference. James Moran, PASSHE vice chancellor for academic affairs, will provide closing remarks..

Lellock's work is funded by a Summer Undergraduate Research Experience Grant from the Pennsylvania State System of Higher Education. She plans to work in the environmental field after graduation.

"SRU students have gained invaluable skills in identification of aquatic organisms and operation of analytical equipment for analysis of metal concentrations, which increases their chances in the job market," DeNicola said. More than half of the graduates who have worked on the project have gone on to graduate school or become employed in the field of environmental science, he said.

"In many cases, their employment was based directly on a skill or experience they gained on the project, and some now work for companies that design and build passive treatment systems," DeNicola said.

"After 12 years of monitoring we have determined that the passive treatment systems are very effective in treating AMD sources into the streams, and that the chemical properties of the water within the streams has improved some. Our main objective for the biological part of the study was to determine if algal communities have responded to previously documented improvements in water quality by comparing long-term temporal trends at treated sites to concurrent trends for the untreated and reference sites. We found the taxonomic changes in algae corresponded primarily to increases in pH and alkalinity at the stream sites below passive treatment," he said.

"Thus far, our findings indicate passive treatment has resulted in moderate recovery of algal communities in parts of the watershed, but that they are still impacted compared to high quality reference streams in the area" he said. "It is impossible to treat all the AMD in the watershed, and there are issues with contaminated stream sediments, but overall the streams have improved from passive treatment"

DeNicola has presented his research at more than a dozen national and international meetings. The project also has resulted in four publications in international journals. He said he is now done collecting data and hopes to write the remaining results in the next two years.

Slippery Rock University is Pennsylvania's premier public residential university. Slippery Rock University provides students with a comprehensive learning experience that intentionally combines academic instruction with enhanced educational and learning opportunities that make a positive difference in their lives.