Endangered species could threaten fire plan The Clinton administration's $1.6billion plan to restore the nation's forests after a summer of recordbreaking fires could run into roadblocks thrown up by the Endangered Species Act. Endorsed by six western governors in September, the plan proposes to prevent catastrophic fire by thinning (logging) trees and burning the understory that has built up during a century of fire suppression. Although this strategy is supported by forest ecologists it could destroy habitats used by endangered species such as the spotted owl and the lynx The administration's restoration plan responds to one of the worst fire seasons in half a century, with more than 6.8 million acres consumed by 80,000 wildfires. Although the plan is welcomed as a needed fix, its implementation could conflict with other environmental concerns such as air quality (see sidebar) and endangered species. The dilemma has already surfaced on the south slopes of volcanic Mount Adams in Washington State, where the suppression of wildfires over the past 90 years has
allowed thick stands of grand and Douglas fir to invade what were previously ponderosa pine forests. This has created new habitat for the endangered spotted owl, according to Dennis Seidman, a natural resource planner with the U.S. Forest Service (USFS). To further confound this ecological conundrum, the spruce budworm, a moth caterpillar, finds a comfortable niche there, as it defoliates the invasive firs. The dense stands contain a huge volume of dead trees that are now fuel for a catastrophe waiting to happen, Seidman says. To reduce the chance of a large, intense fire, the USFS would like to thin the firs and burn the understory, eventually restoring the forest to fire-tolerant ponderosa pine. But they have put the plans on hold because the pine is not favored by the owls. "The debate is over how much, if any, logging an area can handle without degrading spotted owl habitat" Seidman If the USFS was not still cutting old growth forests on the wet western side of the cascades, which is the original habitat for
Forest fires pollute western air Forest fires are an increasingly important component of air pollution in the West, as high fuel loads from a century of fire suppression combine with the warmer and drier conditions spawned by global climate change, scientists say. Particulate matter (PM) from fires, which lodges in lungs and causes respiratory problems, severely affected air quality in Montana this summer, according to John Coefield, a meteorologist with the Montana Department of Environmental Quality. Impairing the health of residents in the western part of the state, the smoke was detected as far away as Chicago, says Coefield. In towns adjacent to fires, such as Missoula and Hamilton, levels of PM10 were 5-6 times higher than federal standards, he says. The smoky summer boosted emergency room visits, prescriptions for asthma inhalers and instances of angina and heart attacks, according to Michael Spence, medical officer for the state of Montana. These concerns will limit the number and timing of prescribed burns to reduce levels of forest fuels, Coefield says. Prescribed burns, because they hug the ground and do not disperse smoke high into the air as catastrophic fires do, can generate more local health concerns than large fires, he says. To keep smoke from controlled burns below federal air quality standards, Coefield's office runs a model each day that determines where and how much burnina can be done. —J.P.
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This summer's record-breaking wildfires have sparked a debate over how to reduce fire danger without harming endangered species or air quality.
spotted owls, it wouldn't be in this dilemma, charges Joe Scott, conservation director for the Northwest Ecosystem Alliance. In addition to endangered species concerns, the forest restoration plan has sparked a political battle over how to prevent large fires. The timber industry advocates more logging of large-diameter trees, whereas environmentalists claim clear-cut logging causes intense fires. "Large trees need to be thinned because they have grown too densely and can lead to intense fires that kill everything," claims Frank Backus chief forester at SDS Lumber Co. in Bingen WA Scientists say both fire suppression and certain logging practices have led to the fuel buildup in the nation's forests. A century ago, periodic cool ground fires thinned the understory, leaving widely spaced mature trees that could not transfer hot crown fires to each other, explains Nate
Government Watch Stephenson, a research ecologist with the U.S. Geological Survey. Now, dense stands of young trees create a ladder for ground fires to climb into the crowns of large trees, which leads to hot, out-ofcontrol fires. "Both mechanical thinning and prescribed burns are needed to restore western forests," Stephenson emphasizes. Some forests have so much fuel that prescribed burns can run out of control if the weather suddenly changes, such as the spring blaze that torched Los Alamos, NM. In some areas, the trees must first
be thinned by chainsaw, he says. But logging small trees is not always economical and often cannot be done in remote areas or on steep slopes, Stephenson says. Although prescribed burns can restore wetter forests, such as those below 7000 ft on the western slope of the Sierra Nevadas, their use may be limited because of air quality concerns, he says. Stephenson emphasized that not all forests, especially high elevation ones such as those in Yellowstone National Park have been altered by fire suppression JANET
PELLEY
Cropland net emitter of greenhouse gases High soil nitrogen levels are causing U.S. cropland to release more greenhouse gases (GHG) to the atmosphere than crops remove, according to research presented at the Ecological Society of America meeting in August and reported in Science (2000, 289, 1922-1924). The findings affect U.S. and Canadian hopes that soil carbon sequestration on farms could receive international credit for slowing global warming. The research shows that practices such as reduced tillage and fertilizer use lower GHG generation, but the potential of farmland to act as a carbon sink may be less than officials at the U.S. Department of Agriculture (USDA) anticipated. Previous studies only looked at capture and release of carbon on cropland. The new research calculates a complete budget for carbon dioxide (C02), methane (CH4), and nitrous oxide (N20), says Phil Robertson, an ecosystem scientist at Michigan State University. The budget balances carbon stored in the soil against C0 2 released during manufacture and transport of fertilizer, and natural soil generation of N 2 0. The long-term study (1991-1999) compares conventional, no-till, and organic crops to unmanaged ecosystems in the Midwest. For all die cropping systems, N 2 0 is the greatest single source of global warming potential, Robert-
son says. N 2 0 has a global warming potential 310 times that of C0 2 and is produced by soil bacteria from fertilizer components such as ammonium (NH4+) and nitrate (N03~). "Accelerated N 2 0 production depends on having lots of nitrogen in the soil, which can come from fertilizer, organic matter in the soil or biological fixation of nitrogen gas by alfalfa or clover," Robertson explains. Conventional fields have the highest global warming potential, due to fertilizer-driven N 2 0 flux from soils and the vast amounts of COz produced during the manufacture and transport of fertilizer. No-till agriculture reduces that potential by more than 80% by storing the carbon from crop residues in the soil, according to Robertson. Other practices, such as organic agriculture and planting cover crops like annual rye grass in the fall, slash global warming potential by half by lowering fertilizer use and better tailoring nitrogen application to crop needs. These practices combined with no-till could neutralize U.S. agriculture's annual release of 60 million metric tons of C0 2 equivalents, says Robertson. Moreover, abandoned farm fields have a negative global warming potential because they have low rates of N 2 0 emissions that are more than offset by the large amounts of
allow the Canadian government to step in and force Ontario, which along with the province of Quebec is Canada's major source of smog, to meet U.S. emissions standards if the province does not act on its own, he claims. N0 X emissions from Ontario's coal-fired power plants are three times higher than what would be allowed under U.S. regulations proposed for 2003 (Environ. Sci. Technol, 1999, 33 (3), 64A). Final negotiations were expected to take place in October, and the treaty is expected to be signed by the end of this year.
Full disclosure on bottled water? Bottled water may have to carry labels proving its purity if the U.S. Food and Drug Administration (FDA) has its way. In a Federal Register notice (2000, 65(166), 51,833-51,839), FDA recommends that bottled water reveal the same information on contaminants that water utilities are required to provide to their customers under the Safe Drinking Water Act. These annual reports describe the source of the tap water and disclose the levels of a host of regulated contaminants. Unlike the tap water reports, however, bottled water labels would not have to include explanatory information on recommended maximum levels of contaminants and their reduction targets. Although FDA's recommendation has not yet been enacted, it is a blow to the bottled water industry, which maintains that additional labeling requirements are unnecessary. More than half of all Americans drink bottled water, making it a $4 billion-peryear business. In contrast to its image of crystal-clear purity, about one-fourth of bottled water Continued on Page 457A
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