Over the years, acid deposition, commonly referred to as “acid rain,” has rendered dozens of the lakes uninhabitable for fish and other wildlife. Sulfuric acid from industry pollutants and high levels of nitrogen influenced by nitric oxide that comes from vehicle exhaust are primary sources of acid rain.

Recently, the DFWI has found that some of the most severely affected lakes are starting to recover. The reductions of sulfate are likely correlated with the 1990 Clean Air Act, a federal mandate to significantly reduce emissions that cause acid rain, says Charles Boylen, DFWI associate director and professor of biology who is Co-Project Director of this Adirondack lake program.

Two years ago, the EPA commissioned an external board of scientists to review the program, which received a glowing report card.

The external board chaired by Norman Yan indicated in its report that “Given the history of acid rain in the Adirondacks, and the quality and scope of the work being conducted in this program, the reviewers believe that this program is one of the most important acid-rain/recovery monitoring programs in existence in the world”.

The report continued: ““The key strengths of the program are the duration of planned work when compared with the anticipated timeframe of water-quality improvements, and the quality and scope of the existing and planned work. In the reviewers’ opinion, no other acid rain/recovery monitoring program has the breadth or focus of the AEAP program-its inclusion of physical and chemical limnology, and bacteria, phytoplankton, zooplankton, macrophytes and fish. Further, no monitoring program is covering multiple lakes, several times per year for 10-15 years.”

“Recovery doesn’t happen overnight,” Boylen says. “One of the reasons we need long-term data is that other factors can come into play. More or less rainfall in a year, for instance, can lead to a temporary shift in acid-rain levels. You need to track specific data over 10 to 15 years. We’ve done that and we are continuing our long-term research efforts.”

Invading Our Waters
Boylen and other DFWI researchers are also well known for their research on invasive species. Due to a lack of natural predators, these non-native plants and animals typically spread rapidly, disrupting native habitats.

		Zebra mussels are considered a prolific nuisance, as they grow in clusters that wreak havoc on the water intake pipes of water treatment facilities, power plants and industry.

The size of a dime and named for their distinctive black and white stripes, zebra mussels are an invasive species that came to American waters in 1986 via international shipping vessels. By the 1990s, they were well established in the Hudson River and Lake Champlain. Clustered together, the mollusks can displace native species and clog water intake pipes, and impact boats and docks.

At the time, no zebra mussels were known to exist in Lake George. Still, Nierzwicki-Bauer thought the time had come to take a proactive approach, given the proximity of Lake George to Lake Champlain is only a few miles.

As part of their early detection work, the researchers placed small, retrievable, underwater metal platforms, called spat traps, at different locations and at varying depths in the lake to determine the presence of the mussels in different stages of development.

Rensselaer scientists have also developed a DNA probe to detect the microscopic larvae.

Zebra mussel larvae were first found in the lake in 1995, but scientists believed that the water chemistry — probably low calcium and pH levels — kept them from maturing. Then, in 2000, DFWI researchers found thousands of the adult mollusks in the southern basin. In response, divers manually removed more than 22,000 zebra mussels. A culvert carrying storm runoff with high calcium levels may have been the factor for the proliferation.

Just last year, three juvenile zebra mussels were found on the spat traps at the northern end of the lake. DFWI continues to be vigilant in preventing the invasive species from colonizing through public awareness, management efforts and further research.

International Waters
Nierzwicki-Bauer also has been involved in a number of projects overseas. In one project, she worked with an international team on the study of the symbiotic association between blue-green algae and a water fern, used as a natural fertilizer in rice patties in India, China, and the Philippines.

After it matures, farmers turn the plant-algae association into the soil, nitrogen is released, which then is used to fertilize the rice. The research team recently found other bacteria that are part of symbiotic relationship. Presently, Nierzwicki-Bauer’s group is working with molecular techniques to determine how the bacteria genes are expressed when they are in the symbiotic association and how that impacts the system.

In other research abroad, EES professor Jun Abrajano has discovered a rare group of microorganisms in several hot springs in the Philippines. The bacteria, which thrive in a harsh, sulfidic, oxygen-free environment, was known to exist only in New Zealand. Among other applications, the bacteria could be used to advance energy production and wastewater cleanup.

“Given the importance of water quality and quantity in the 21st century, it is not surprising that Rensselaer is drawing on its expertise in science, engineering, and other fields to help protect and restore water resources,” says Nierzwicki-Bauer. “This is an appropriate and critical role for Rensselaer as a leading technological research institute.”

Link of interest:
Marianne Nyman Receives NSF CAREER Award