Stream of knowledge

Water research helps manage critical resource in ever-changing world

July 14, 2015 | by MEGHAN LEPISTO

Water, essential for life, is under close scrutiny at UW-Madison.

More than 100 faculty and scientists across campus are involved in water-related research and scholarship, exploring everything from agricultural runoff to the global carbon cycle and from aquatic insects to water as a human right.

Many of these researchers – spanning biological, physical and social sciences, and arts and humanities – presented their work at a free public symposium in May hosted by the university’s Center for Limnology, Sea Grant Institute, Water Resources Institute and the Nelson Institute.

In concert with the event’s theme, Water@UW: A Wisconsin Idea Symposium, below is a sampling of projects shared at the meeting that answer important scientific questions and reflect the university’s service to the state and beyond. 

Fishing for DNA

Ever peer into a lake and wonder what’s beneath the surface? Patrick Krysan of the Genome Center of Wisconsin, within the UW-Madison Biotechnology Center, is employing a new technology to help answer that question. A sample of lake water is like biological soup, he explains, containing thousands of tiny fragments of DNA from all the organisms in the ecosystem. Next-generation DNA sequencing sorts and counts these DNA fragments to yield a lake census.

This method has the potential to be more precise, efficient and affordable than a manual fish census and presents new opportunities to study fish community structure, predator/prey balance, and the presence or absence of invasive species, Krysan says – important issues for fisheries managers and ecologists.

Farmer-led watershed councils

Initiatives to minimize the impact of nutrients moving across land and into lakes and rivers have long focused on agriculture, but top-down approaches have not always persuaded farmers in critical areas to use water-protecting management practices says Ken Genskow, an associate professor of urban and regional planning.

Genskow suggests that a relatively new approach – farmer-led watershed councils – may be more effective. With support from conservation organizations and agencies, farmer-led councils help define concerns, develop control strategies and allocate a small pool of incentives. Learn more about a Wisconsin pilot effort: blogs.ces.uwex.edu/wflcp 

Inland waters and the global climate system

Ankur Desai, an associate professor of atmospheric and oceanic sciences, is gathering unprecedented data as he studies fluxes in carbon, water and heat off of several Wisconsin lakes.

By gathering direct and continuous measures at a half-hour time scale, Desai is trying to shed light on what role inland waters may play in the global climate system and in balancing anthropogenic carbon. We know that large lakes play a role in regional climates, for example through lake-effect snow, but what about small lakes? Desai is attempting to quantify these links.

Coastal engineering research and extension

Gene Clark, a coastal engineering extension specialist with UW Sea Grant Institute, is part of a team studying the causes and extent of freshwater-accelerated corrosion and solutions to repair and rehabilitate failing Great Lakes steel infrastructure.

The work began at the Port of Duluth/Superior in Lake Superior, where more than 14 miles of steel sheet piling are in place. The researchers have tested marine coatings and encapsulation methods at the port with promising results. Seventeen facilities have utilized the technology and the team is sharing their findings with other Great Lakes ports and harbors through outreach, publications and on the Web, earning a national Sea Grant award. 

Projections of Great Lakes water levels

Global climate models show the Great Lakes basin getting warmer and wetter in the 21st century, but the question remains how lake levels will respond, says Michael Notaro, associate director of the Nelson Institute Center for Climatic Research.

To develop future projections for Great Lakes’ channel flow and water levels, he and colleagues are applying a regional climate model and an interactive lake model to dynamically downscale coarse global climate models to a regional level with high resolution. 

Tailoring climate information for water management

Paul Block, an assistant professor of civil and environmental engineering, links climate information with water resources management models to understand societal impacts, specifically through season-ahead forecasts. In coordination with climate scientists, his research group forecasts and communicates conditions a season in advance – for example, related to precipitation, stream flow, or the propensity for floods or droughts – and then in concert with economists and social scientists examines the policy implications.

The work has applications for energy, agriculture, municipalities and more. Locally, Block is helping to forecast water quantity along the Wisconsin River and in the Central Sands region, and water quality with regard to algae blooms and beach management; he’s also leading projects in Texas, Chile and Ethiopia. 

Aquatic insects link lakes and land

In a good year, about 110 metric tons of tiny midges emerge from Lake Myvatn in northern Iceland and are deposited on the shore, equivalent in mass to about half a million Big Macs being built from the lake and dropped near shore. This is according to Claudio Gratton, a professor of entomology who has witnessed the phenomenon.

As larvae, the midges feed on sediments in the lake, then emerge as adults by the trillions to mate. Most of the insects die and decompose over near-shore land, releasing nutrients – rivaling about one-fifth of what a local farmer applies to their land in fertilizer – and transforming the ecosystem to grassland-like conditions.

Midges are found throughout the world, including in Wisconsin, and with about a third of Wisconsin land within 200 meters of a body of water, Gratton suspects that some of these same processes may be occurring in the Badger State. He’s working to estimate wherein the landscape the effects are most likely.

Managing a lethal fish virus 

Viral hemorrhagic septicemia virus (VHSV), an invasive species that arrived in Wisconsin in 2003, is lethal to fish, including economically important sport fishes in the state. But the current approved test for the virus is also lethal and is slow to provide results. In response, School of Veterinary Medicine Professor Tony Goldberg was part of a team that, with assistance from the Wisconsin Department of Natural Resources, developed two new tests for the virus that are cheaper, faster, accurate and non-lethal.

The new tests are being run at the Wisconsin Veterinary Diagnostic Laboratory and used by the DNR and some commercial operations. To study exposure patterns and herd immunity, and to find ways to better manage the virus, Goldberg’s group applied the tests to freshwater drum in Lake Winnebago. The work, funded by Wisconsin Sea Grant, indicates that many fish have been exposed, and that the virus is transmitted actively even in years when fish kills are not seen. 

Sediment transport in agricultural watersheds

Sediment fingerprinting may sound like a technique from a crime scene investigation. But Anita Thompson, a professor of biological systems engineering, uses the method to estimate the contributions from various sources, such as cropland or stream banks, to the sediment that makes its way into a stream.

The findings, in combination with process-based models, allow the pinpointing of critical source areas for polluting sediment. This in turn informs targeted implementation of management practices.

The research is part of Thompson’s larger work aimed at understanding sediment as it moves from its source through a watershed drainage network and ultimately to its point of impact, all with the goal of reducing the amount of sediment that arrives at streams or other waters. 

The fate of organic contaminants

Christy Remucal, an assistant professor of civil and environmental engineering, studies the fate of organic contaminants – things like pesticides, pharmaceuticals, personal care products and endocrine disrupters such as Bisphenol A – in both natural systems like lakes, and in engineered systems such as drinking water treatment plants.

One area of focus is the photochemical degradation of these contaminants – when sunlight reacts with the molecules, what happens, how fast, and what are the products of the reaction? Remucal is also studying what happens when you shine light on chlorine – used for disinfection at most drinking water treatment facilities in the United States – and whether the reactive oxidants that are produced can be applied safely to help remove contaminants. Existing drinking water disinfection systems do a good job removing particles and pathogens from water, Remucal says, but they’re poor at removing the organic compounds she studies. 

High-precision mercury isotope ratios 

How does mercury get into fish? And where did it originate? Jim Hurley, director of the UW Aquatic Sciences Center, which houses the UW Sea Grant Institute and the UW Water Resources Institute, is seeking answers in coordination with the Wisconsin State Laboratory of Hygiene and the U.S. Geological Survey.

With the State Lab’s extraordinary analytical capabilities, Hurley and collaborators can examine high-resolution naturally occurring mercury isotopes – a recent advancement in the field. Subtle differences in mercury isotope fractionation lead to unique signatures, similar to DNA fingerprints, that allow researchers to determine whether mercury came from industry, the watershed or precipitation. Hurley and colleagues are now using the tool to assess differences in mercury concentrations and sources across the Great Lakes and across fish types.

Photo credits, from top to bottom: FISHBIO, Carl Wycoff, Josh Haroldson, Bitsorf, VXLA, NOAA, Claudio Gratton, USFWS, Tim Hettler, Michelle Tribe