奥林巴斯e pl1-As record Appalachian wildfires fizzle out, scientists look to learn from the destruction佳能sx10跑得速的高跟鞋塑料做的保暖衣……带你寻找进博会之最_1—As record Appalachian wildfires fizzle out, scientists look to learn from the destruction On a dry October day this year, a stray lightning strike ignited a fire in Georgia’s ChattahoocheeNational Forest. The resulting wildfire, eventually stretching 11,000 hectares and burning for 6 weeks, marked an early start to the record-breaking fall fire season that the southeastern United States experienced this year. More than 50 major wildfires crawled through eight states, burned more than 40,000 hectares, and led to 14 deaths. The fires, which were more aggressive and more difficult to contain than usual, even produced smoke visible from space.Now, with Appalachia’s wildfires fizzling out, fire scientists and fire managers are figuring out what they can learn from the conflagrations. In part, they hope to assemble data that might help them identify areas most at risk of dangerous fires, and encourage management practices—such as the use of prescribed burns—which could limit future outbreaks.“We want to know how to move forward scientifically,” says Helen Mohr, a forester with the United States Forest Service (USFS) Southern Research Station who directs the Consortium of Appalachian Fire Managers and Scientists (CAFMS), based at Clemson University in South Carolina. “We want to inform scientists, managers, and communities how to keep their homes and forests safe.”This fall’s wildfires were “really a perfect storm, so to speak,” says Donald Hagan, a forest ecologist at Clemson University. The blazes burned so quickly and out-of-control that counties in Kentucky, North Carolina, and Tennessee declared states of emergencyand hundreds were hospitalized. One significant factor contributing to the fires’ speed and destruction is an extreme drought in the region, affecting states including Georgia, Tennessee, and North Carolina. That meant no rain to tamp down flames, and plenty of dry brush and wood that acted as fuel. In some areas, more than a century of fire suppression has allowed dead trees and other fuel to build up to dangerous levels, Hagan says. A lack of fire also allowed oily shrubs that burn easily, such as mountain laurel and rhododendron, to take over large swaths of forest. So when fires started, they tended to burn longer and spread more quickly, he says.Controlled burns would help preserve forest ecosystems and limit the reach of wildfires, but they have become difficult to perform. “The conditions have to be just right for safety reasons,” says Mike Brod, the staff officer for fire and natural resources at Chattahoochee-Oconee National Forests in Georgia. People often live in or near forests in need of burning, Brod notes, and the smoke created by controlled burns is another big concern. If the smoke doesn’t drift high enough into the atmosphere or blow in the right direction, it can drift into nearby communities and pose serious health threats to people. This fall, wildfire smoke in some areas reduced air quality to code purple—the most dangerous coding—prompting evacuations.Understanding how that smoke affected human health is one possible focus of postfire studies now being planned by CAFMS together with USFS’s Southern Research Station and Region 8 scientists, the Fire Learning Network, and The Nature Conservancy. The team also plans to look into how fire behavior changed depending on available fuel types, and how plant and animal life in burned areas is rebounding. And “we’re really curious about the role of climate change” in eastern wildfires, says Mohr, noting that some climate models suggest regional droughts could become more common in the future. The research effort could include data-collecting trips to burned areas and analyses of images and other data collected by satellites.Researchers will also be thinking about how better to communicate the benefits and risks of woodland fires to the region’s residents, says Mohr, who works as a firefighter. “You can’t hide under a rock and say the wildfires were all good or all bad,” Mohr says, noting that some kinds of trees and ecosystems need fire to reproduce and thrive. But people can unknowingly make wildfires more dangerous by suppressing natural fire, and by planting flammable bushes around homes located in fire-prone forests. “We all want to live at a beautiful mountainside with woods at our back deck, but the risks are like living on beach with hurricanes—fire is bound to happen,” she says. “A big part of what we need is better communication on how to protect your home.”There’s no timeline yet for when research will begin, but Mohr hopes things will be set in motion soon.