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Mountain Research Station chief expands understanding of alpine environments

Bill Bowman is a Colorado native whose parents graduated from the University of Colorado. But attending the flagship university of his home state was not his plan.

It happened by chance, and it worked out so well that he’s returned twice, once as an undergraduate student and later as a member of the faculty. Now, he’s an eminent biologist who runs a quintessentially Colorado project, CU’s Mountain Research Station.

Though he was born in Denver, Bowman grew up in Southern Arizona. In high school, he did research with the University of Arizona. It was then that he met two CU biologists, Jane and Carl Bock, who “talked up the department here and said it would be a great place to come.”

He enrolled with the help of a partial scholarship to be on the CU swim team. Bowman knew he wanted to be involved in biology, though he admits to harboring romantic ideas about “ecology.”

At the same time, he knew that biology was a hard-core science involving a good deal of tedium. “As a high school student, I spent time counting grass seeds for an ecologist at the U of A,” Bowman says. “It made me realize how important it was to collect the data.”

In 1981, Bowman earned a degree in biology and went to Duke University, where he got his doctorate in 1987. Did he think he’d end up back at CU? “No, never,” he intones.

But while doing post-doctoral work in Australia, Bowman noticed an advertisement for a job at CU, a joint appointment between CU’s biology department and the Cooperative Institute for Research in Environmental Sciences, now directed by CU geography professor Konrad Steffen.

A year and a half later, Bowman switched to another post, a joint appointment between biology and CU’s Institute for Arctic and Alpine Research. One of his duties was managing the institute’s Mountain Research Station, an interdisciplinary research facility devoted to advancing the study of mountain ecosystems.

The station, about 25 miles west of Boulder, has existed since 1921 and is situated not far below a cluster of research projects on Niwot Ridge, which is above timberline near the Continental Divide. More than 40 researchers from CU, other universities and the federal government study a host of biotic and physical systems in the alpine environment, along with how environmental changes affect those systems.

Bowman notes that the alpine environment in Colorado is sometimes described as “extreme.” But alpine plants and animals have adapted to those conditions. So the “extreme” moniker “is very much a human perspective.”

Bowman cites recent work his research group has done about how plants shape their environment. Plants can change the soil to alter the growth of fungi or bacteria, affecting nearby plants, which are competing for resources. “It’s like chemical warfare between plants,” he says.

That work is significant. Courtney Meier, one of Bowman’s graduate students (who recently earned his doctorate), published a study about this below-ground “chemical warfare” in the December 2008 edition of the Proceedings of the National Academy of Sciences.

The paper was adapted from part of Meier’s dissertation, Bowman says, adding, “To be able to publish one of your thesis chapters in PNAS is a huge deal.”

That’s one reason, no doubt, Bowman says his group’s work on chemical warfare among plants is especially “intellectually satisfying.” But in terms of work that has an application for policy, Bowman cites his work on nitrogen deposition in soils.

He notes that a certain concentration of nitrogen can increase the growth of trees and other plants and influence the abundances of some species. Once the ecosystem reaches a “critical load” of nitrogen, however, there are negative effects including soil acidification.

In some environments, including alpine systems such as that on Niwot Ridge, the concentration of nitrogen has been increasing. But Bowman says the cause of Niwot Ridge’s rising nitrogen concentration is not clear. It could be partly from agricultural operations. It could be air pollution from Los Angeles and Salt Lake City.

The culprits may be both the burning of fossil fuels and agriculture. Agriculture is implicated because microbes can convert fertilizers into airborne ammonia (a nitrogen compound), which can be deposited in alpine soil.

The main finding of his nitrogen research is that we’ve reached and maybe exceeded a threshold in which human impacts are noticeable. Colorado’s alpine systems are in much better shape than others, however.

In the November 2008 edition of Nature Geoscience, Bowman and colleagues from the University of Montana, the U.S. Geological Society and the Slovak Academy of Sciences reported on the marked increase in nitrogen deposition in alpine areas of Slovakia.

In that country, which is said to suffer some of the worst air pollution in Europe, “It’s a much more extreme situation, and we don’t want to reach that in Colorado,” Bowman says.

Citing one example, Bowman notes fly fishing, which helps drive Colorado tourism. If the land and water become too acidic, “It’s certainly possible that we could reach a stage where fish are dying.”

If such damage came, it might be two decades away, he says, adding that much depends on the economy, the technology we use to develop power and the practices used in farming.

Bowman says running the Mountain Research Station has been “fun and challenging.” He’s proud of the station’s science-discovery outreach to K-12 students. Many of them are from metropolitan areas and from ethnic groups under-represented in science. Many are young women, who are also under-represented in biology.

Though they may have grown up in Boulder or Denver, some of these kids have never been to the mountains. The hope is that “just being in the mountains and being exposed to researchers” will ignite an interest in science.

More than three decades after Bowman started his academic career by helping researchers count seeds, he’s now sowing seeds—for the next generation of scientists.