Yellowstone fires of 1988

context: en: Before the middle of the 20th century, most forest managers believed that fires should be suppressed at all times. By 1935, the U.S. Forest Service's fire management policy stipulated that all wildfires were to be suppressed by 10 a.m. the morning after they were first spotted. Firefighting crews were established throughout public lands, and generally staffed by young men during fire seasons. By 1940, firefighters known as smokejumpers would parachute out of airplanes to extinguish flames in remote locations. By the beginning of World War II, more than 8,000 fire lookout towers had been constructed in the United States. Though many have been torn down due to increased use of airplanes for fire spotting, three are still used each year in Yellowstone. Firefighting efforts were highly successful, with the area burned by wildfires reduced from an annual average of 30,000,000 acres (120,000 km2) during the 1930s, to between 2,000,000 acres (8,100 km2) and 5,000,000 acres (20,000 km2) by the 1960s. The need for lumber during World War II was high and fires that destroyed timberland were deemed unacceptable. In 1944, the U.S. Forest Service developed an ad campaign to help educate the public that all fires were detrimental, using a cartoon black bear named Smokey Bear. This iconic firefighting bear can still be seen on posters with the catchphrase "Only you can prevent forest fires". Early posters of Smokey Bear misled the public into believing that western wildfires were predominantly human-caused. In Yellowstone, human-caused fires average between 6 and 10 annually, while 35 wildfires are ignited by lightning.Some researchers, as well as some timber companies and private citizens, understood that fire was a natural state of affairs in many ecosystems. Fire would help clean out the understory and dead plant matter, allowing economically important tree species to grow with less competition for nutrients. Native Americans would often burn woodlands to reduce overgrowth and increase grasslands for large prey animals such as bison and elk. As early as 1924, environmentalist Aldo Leopold argued that wildfires were beneficial to ecosystems, and were necessary for the natural propagation of numerous tree and plant species. Over the next 40 years, increasing numbers of foresters and ecologists concurred about the benefits of wildfire to ecosystems. In 1963, a group of ecologists consulted by the National Park Service released a report recommending that wildfires should be allowed to periodically burn to restore the environmental balance in parks. The Wilderness Act of 1964 helped to address the role of fire as a natural part of ecosystems. By 1968, the National Park Service had adjusted its fire management policies to reflect changing attitudes. The service determined that fires that started naturally (by lightning) would be permitted to burn if they posed little risk to human life and property. The service also decreed that under prescribed conditions, controlled burns would be deliberately set to restore balance to ecosystems. Fire ecology became better understood after many forests had aged to maturity and were overdue for a large scale burn.
qas: question: zh_tw: 什麼會應用燃燒的更好？
answers: en: text: aged to maturity

question: zh_tw: 森林管理員想要抑制什麼？
answers: en: text: fires

question: zh_tw: 哪種自然現象可以幫助一些重要的樹種多一些生長空間？
answers: en: text: Fire

question: zh_tw: 控制燃燒的目的是什麼？
answers: en: text: restore balance to ecosystems

question: zh_tw: 消防員大多由哪個年齡組組成？
answers: en: text: young men

context: en: From 1972, the National Park Service began allowing natural fires in Yellowstone to burn under controlled conditions. Fires of this type were referred to as prescribed natural fires. Between 1972 and 1987, a total of 235 prescribed natural fires burned a relatively small 33,759 acres (137 km2) under the directives of the new policy. Of these, only 15 spread to more than 100 acres (0.4 km2). The five years prior to 1988 were much wetter than normal and this may have reduced the area of the fires during that period. The prescribed natural fire policy appeared to be an effective way to manage fires, especially in the Yellowstone region.
qas: question: zh_tw: 制定的自然山火可以在哪個公園使用？
answers: en: text: Yellowstone

context: en: In contrast, in 1988, Yellowstone was overdue for a large fire, and, in the exceptionally dry summer, the many smaller "controlled" fires combined. The fires burned discontinuously, leaping from one patch to another, leaving intervening areas untouched. Intense fires swept through some regions, burning everything in their paths. Tens of millions of trees and countless plants were killed by the wildfires, and some regions were left looking blackened and dead. However, more than half of the affected areas were burned by ground fires, which did less damage to hardier tree species. Not long after the fires ended, plant and tree species quickly reestablished themselves, and natural plant regeneration has been highly successful.
qas: question: zh_tw: 火災結束後，什麼很快自我再生？
answers: en: text: plant and tree species

context: en: In the eastern United States, with its significant rainfall, wildfires are relatively small and have rarely posed great risk to life and property. As white settlements moved further west into drier areas, the first large scale fires were encountered. Range fires on the Great Plains and forest fires in the Rocky Mountains were far larger and more destructive than what had ever been seen in the east. A number of catastrophic fire events over the years greatly influenced fire management policies.
qas: question: zh_tw: 山火在美國哪個地區威脅較小？
answers: en: text: eastern United States

question: zh_tw: 居民們向哪個方向遷移？
answers: en: text: west

context: en: The worst loss of life in United States history due to a wildfire occurred in 1871 when the Peshtigo Fire swept through Wisconsin, killing more than 1,500 people. The Santiago Canyon Fire of 1889 in California and especially the Great Fire of 1910 in Montana and Idaho contributed to the philosophy that fire was a danger that needed to be suppressed. The Great Fire of 1910 burned 3,000,000 acres (12,000 km2), destroyed a number of communities, and killed 86 people; this event prompted various land management agencies to emphasize wildfire suppression. U.S. Government land agencies, including the National Park Service, generally followed the fire management policies established by the U.S. Forest Service, which oversees the majority of the nation's forestlands.
qas: question: zh_tw: 美國森林管理局的職責是什麼？
answers: en: text: oversees the majority of the nation's forestlands