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March 25, 2005--The premiere window on the future of northern forests will continue to provide new views on the effects of global climate change, thanks to renewed support from the U.S. Department of Energy. Aspen FACE (Free-Air CO2 Enrichment) is the world's largest, open-air climate change research facility, and the only FACE site where scientists can study the impact of carbon dioxide and ground-level ozone on forest ecosystems. Since its formation in 1997, more than 75 scientists from nine countries have conducted research at the U.S. Forest Service site near Rhinelander, Wis., to predict how the seemingly inexorable rise in the concentration of greenhouse gases will affect northern forests. "There's no debate about the fact that the composition of the earth's atmosphere is changing," said Professor Kurt Pregitzer (SFRES), who has led a number of studies at the FACE site. "Carbon dioxide and tropospheric ozone are increasing globally, and they affect plant growth in diametrically opposite ways," he said. "Carbon dioxide enhances growth, while tropospheric ozone--the major component of smog--reduces plant production." "One of the only places you can study this is the FACE site in Rhinelander," said Pregitzer. "The experiment has become a real magnet for understanding how forests of the future will grow and function." "Our Aspen FACE studies on young aspen and birch forests have given us insights into how future northern forests will be impacted by atmospheric change. However, it is critically important to see if these early trends continue as these stands begin to mature," said David Karnosky, the Aspen FACE director and a professor at Michigan Tech. "A truly unique component of our Aspen FACE study is that we are able to look at the long-term effects of these greenhouse gases from cradle to grave." The three-year, $5.1 million grant from the U.S. Department of Energy is expected to fund Aspen FACE research through 2008. FACE research completed over the last seven years at this site suggests the following: • Moderate levels of ozone will offset the positive elevated carbon dioxide responses projected for 2050. • Carbon sequestration under elevated carbon dioxide is being overestimated by modellers who do not consider increases in ozone. • Rising carbon dioxide protects trees from more severe ozone damage. • Birch may become more competitive than aspen in future atmospheric conditions. • Effects seen on the three major tree species in the experiment (sugar maple, trembling aspen and paper birch) have cascaded through the ecosystem, even to soil microorganisms. Reliable, scientific studies on climate change are more critical than ever, said Neil Nelson, the USDA Forest Service's project leader of the physiology research unit collaborating on Aspen FACE. "Carbon dioxide and ozone are increasing by roughly 2 percent a year, and the more we theorize about possible effects, the more controversy ensues," Nelson said. "It's important to know what those effects will be on agricultural and forestry communities, because that will drive decision-making on regulatory and energy policy, as well as forest management. Controlling greenhouse gases has huge financial impacts for the automobile and energy production industries." "Global change is one of the key environmental issues of this century," said Kevin Percy, a Canadian Forest Service investigator at Aspen FACE. "For the first time, we are able to examine long-term, community-level responses which give us a better idea how our northern forests may change. This experiment has tremendous relevance to this region." "Aspen FACE and its sister DOE-sponsored FACE facilities across the U.S. are providing invaluable information about future ecosystem structure and function," said George Hendrey, Queens College professor, who led the Brookhaven National Laboratory team that designed the Aspen FACE facility. Aspen FACE is funded jointly by the Department of Energy's Office of Biological and Environmental Research; the National Science Foundation; Global Change Program, USDA Forest Service; North Central Research Station, USDA Forest Service; Michigan Technological University; the USDA National Research Initiative Program; Brookhaven National Laboratory; and Natural Resources Canada, Canadian Forest Service-Atlantic Forestry Centre. |