Inquiring Minds
Illustrations by Michael Sloan

Carbon Lure
Puddle Love
Catch Up

Carbon Lure

Can buiding highways slow global warming?

Sustainable highways: it seems like an oxymoron. How could building new highways possibly cut water pollution and slow global warming? Researchers at UNH's Recycled Materials Resource Center think they know.

Civil engineering associate research professor Kevin Gardner says the "aha!" moment for sustainable highways came in 2003. His research had already shown that exposing the recycled materials used to build roads—coal fly ash, cement kiln dust and recycled concrete—to carbon dioxide could reduce the amount of heavy metals leached into ground water.

At the time, he and civil engineering research professor Taylor Eighmy '83G, '86G were advising UNH students competing in an environmental design contest. One of the tasks was to find a way to remove carbon dioxide, the main suspect in global warming, from the atmosphere. Gardner theorized that the heavy metals were being stabilized through a natural process called carbonation, in which carbon dioxide binds with calcium. This got him wondering if he could kill two dirty birds with one piece of recycled concrete.

The students are working with UNH assistant professor of civil engineering Jo Sias Daniel '94, who performs asphalt research ranging from the concrete, literally, to the abstract. But even her most theoretical project could ultimately contribute to the development of more durable pavements. With a $400,000 grant from the National Science Foundation, she is working out mathematical formulas that will enable engineers to correlate tests on pavement samples in different geometrical shapes. The grant is a prestigious national Career Award for promising young researchers.

Research by master's candidate Jennifer Leipold and other UNH students has demonstrated that carbonation of calcium-rich recycled materials is the "low-hanging fruit" when it comes to cutting carbon dioxide emissions in the United States. "From the perspective of the concrete producing industry, it could have a significant impact because it's a huge producer of carbon dioxide," says Gardner. "The same is true for coal power."

The UNH Office of Intellectual Property Management is trying to patent Gardner's idea. With many countries signed on to the Kyoto Protocol, which calls for significant reductions in carbon dioxide emissions, there is a ready-made market.

More research is needed before a marketable product can be delivered, however. With funding from the Federal Highway Administration, Gardner has constructed a pilot project behind Gregg Hall, investigating both passive and active techniques for drawing air through embankments. Besides measuring carbon dioxide concentration, he is also monitoring moisture—required for carbonation—as well as gas humidity and temperature.

Because of the expense of hauling bulky recycled materials, sustainable roads would not be feasible far from coal-fired power plants, cement kilns or sources of recycled concrete. But Gardner says other materials, such as mine waste, will also work. "There's a lot of materials out there that we haven't even looked at," he says.

Puddle Love

For amphibians, vernal pools are habitat heaven

For amphibians, vernal pools are habitat heaven It's early spring. The nights are damp and drizzly. The temperature's rising. And New England newscasters across the region are issuing Amphibian Advisories—or at least they should be. The frenzied hopping display that appears in car headlights often produces erratic maneuvers by frog-friendly drivers. It's also a sure sign of nearby wetlands.

But roads that run through the temporary wetlands known as vernal pools become death traps for amphibians trying to make the annual journey from their winter uplands to their summer wetlands. Roads also contribute to a reduction in genetic diversity as it becomes harder for amphibians to travel among their breeding grounds.

"One of the most important land management decisions we can make is to keep roads away from vernal pools," says Kim Babbitt '84, UNH associate professor of wildlife ecology.

Wetlands-protection discussions and legislation have, for the most part, focused on large tracts of land—marshes along the ocean's edge, swamps, bogs and other highly visible, economically valuable areas. But the smaller pools of water—the ones that fill in the spring, dry out in the summer, and often recharge with groundwater in the fall—have, historically, been overlooked. "Lots of people have no idea of their significance," says Mike Marchand '03G, wetlands systems biologist with the N.H. Department of Fish and Game. "They might just see this depression in the woods as a place to dump their grass clippings, not realizing that what they're standing in is actually a vernal pool that has dried out for the summer."

This drying-out feature is part of their significance. Because vernal pools are temporary, they are fish-free, and the larvae of amphibians like the wood frog and the spotted salamander can develop safely.

Ironically, efforts to protect these temporary wetlands are virtually pointless if surrounding uplands are not protected as well. Wood frogs, for example, spend most of their lives in upland areas, going to the water only to lay their eggs. Turtles do the reverse.

In central Maine, Nicole Freidenfelds '06G, working closely with Babbitt, has been studying upland habitat. To conduct her research, Freidenfelds spent countless hours mucking about in 11 experimental pools and radio-tracking wood frogs.

Just for the record: tracking these two-inch wood frogs takes patience. Research subjects are first fitted with tiny belly harnesses of Teflon tubing. Transmitters the size of a pinky fingernail are attached with cotton thread to each harness. "You have to experiment to get it right—not too tight or too loose," says Freidenfelds, adding that a froggie fitting is definitely a two-person job.

The 33 hoppers who were successfully tracked throughout the project were observed seven days a week from April through August and on weekends through November. The researchers hope to draw some conclusions about where wood frogs spend most of their lives after their first few months.

Freidenfelds would like to determine how far they can go and what impact clear cutting and other disturbances might have on their ability to survive in a treacherous habitat.

Catch Up

Closing fishing grounds may revive failing fisheries

In New England, virtually every unprotected apple tree is attacked by a tiny weevil called the plum curculio, which causes most of the fruit to drop off in June. Plus there are mites, scales, worms, bugs, caterpillars, moths, mildews, rusts and rots to contend with. Twenty-five years ago, growers responded to this biological onslaught by spraying, often. "We used to spray religiously every 5 to 7 days for apple scab, and if we got a big rainstorm overnight, we'd spray again the next day," recalls Chip Hardy '74, a fifth-generation apple grower in Hollis, N.H.

Enter Alan Eaton, who joined UNH Cooperative Extension in 1978. In graduate school, he had acquired a doctorate in entomology but no experience with apples and their pests. Yet he chose to accept a seemingly impossible mission: to convince apple growers and other farmers in New Hampshire to reduce their dependence on chemical sprays and try an approach now known as Integrated Pest Management (IPM).

Eaton's first task as IPM coordinator was to convince three apple growers to try the new technique on a small subplot of their orchards for one season. Since he was, in effect, asking them to risk $15,000 to $20,000 worth of crop for the sake of saving a few hundred dollars in spray, he was not surprised that many were hesitant. But Eaton did find three growers who were willing to count mites and maggots and keep track of temperature and rainfall. Spray was to be applied only when pests reached a certain threshold. Eaton, plant pathologist Bill MacHardy and several graduate students also helped the growers make use of genetics, biological controls and physical barriers. The combined approach prevents the development of resistant pests, Eaton explains, because "they aren't able to evolve in four directions simultaneously."

To their amazement, the growers saved more than 50 percent in spraying costs on the trial plots. Since then, UNH extension scientists have never lacked for growers eager to learn the latest information on pest life cycles and control methods. Growers can now base their decision to spray for apple scab not on the calendar but on the number of "degrees days" and hours of leaf wetness required for the fungus to release its spores. Eaton estimates growers are spraying 30 to 40 percent less on apple scab alone.

In a report on the IPM program's impact over the past 25 years, Eaton found that New Hampshire apple growers have saved more than $7 million in spraying costs while improving the quality of their product. (IPM has also been applied to other crops in the state, including sweet corn, blueberries, potatoes, poinsettias, bedding plants and strawberries.) Other benefits include a reduction in pesticide exposure and ground- and surface-water contamination, and an increase in the population of beneficial insects.

In fact, Eaton has introduced three parasitic insects that eat apple pests, including a wasp that attacks the European sawfly and "would rather die" than eat anything else. Once established, the wasp will continue to partially control the sawfly all on its own, says Eaton. "And from now until the next ice age," he adds, "everyone will benefit from growers' spraying less."

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