In the United States, it had been commonpractice since the late 1960s not to suppress natural forest fires. The “let itburn” policy assumed that forest fires would burn themselves out quickly, withoutcausing much damage. However, in the summer of 1988, forest fires inYellowstone, the most famous national park in the country, burned for more thantwo months and spread over a huge area, encompassing more than 800,000 acres.Because of the large scale of the damage, many people called for replacing the“let it burn” policy with a policy of extinguishing forest fires as soon asthey appeared. Three kinds of damage caused by the “let it burn” policy were emphasizedby critics of the policy.
First, Yellowstone fires cause tremendousdamage to the parks trees and other vegetation. When the fires finally diedout, nearly one third of Yellowstone’s land had been scorched. Trees were charredand blackened from flames and smoke. Smaller plants were entirely incinerated.What had been a national treasure now seemed like a devastated wasteland.
Second, the park wildlife was affected aswell. Large animals like deer and elk were seen fleeing the fire. Many smallerspecies were probably unable to escape. There was also concern than the destructionof habitats and the disruption of food chains would make it impossible for theanimals that survived the fire to return.
Third, the fires compromised the value ofthe park as a tourist attraction, which in turn had negative consequences forthe local economy. With several thousand acres of the park engulfed in flames,the tourist season was cut short, and a large number of visitors decided tostay away. Of course, local businesses that depended on park visitors sufferedas a result.
- Main point: 专家主张废除“随它燃烧”的策略
- Sub point 1: 会对国家公园的植物造成伤害#p#副标题#e#
- Sub point 2: 会对国家公园的动物造成伤害
- Sub point 3: 火灾会降低公园对游客的吸引力
Actually, fires are natural part ofecological cycle and their role is not just destructive but also creative. Thatis why the “let it burn” policy is fundamentally a good one, even if itsometimes causes fires of the 1988Yellowstone fire. Let’s look at what happenedafter 1988 fire.
First, vegetation. As you might imagine, scorchedareas were in time colonized by new plants. As a matter of fact, the plants inYellowstone became more diverse because the fire created an opportunity forcertain plants that could not grow otherwise. For example, areas where thetrees have been destroyed by the fire could now be taken over by smaller plantsthat needed open and shaded space to grow. And another example, seeds ofcertain plants species won’t germinate unless they’re exposed to very highlevels of heat. So, those plants started appearing after the fire as well.
It’s a similar story with the animals. Notonly did their populations recover, but the fire also created newopportunities. For instance, the small plants that replaced trees after thefire created an ideal habitat for certain small animals like rabbits and hares.And when rabbits and hares started thriving, so did some predators thatdepended on them for food. So, certain food chains actually became strongerafter the fire than they were before.
And last, fires like 1988 Yellowstone firewould be a problem for tourism if they happened every year. But they don’t. Itwas a very unusual combination of factors that year, low rainfall, unusually strongwinds, accumulation of dry undergrowth that caused fire to be so massive. This combinationhas not occurred since and Yellowstone has not seen such a fire since 1988.Visitors came back to the park next year and each year after that.
- Main point: “随它燃烧”政策基本上是正确的
- Sub point 1: 植物会在大火之后恢复而且生长的更好
- Sub point 2: 动物也会在大火之后恢复，食物链会更加稳定
- Sub point 3: 只有每年都发生火灾才会影响当地旅游业，但是从1988年后再也没有发生
The reading passage argues that the"let it burn" policy should be replaced by the policy of extinguishingforest fires as soon as they appeared. However, the professor raises serious counterargumentsagainst the reading paragraph by providing three aspects as listed below: First,according to the speaker, the natural forest fires are a cycle of creative eventhey have a large scale of the damage, and after the fires, new plants which becamemore diverse than before existed in the Yellowstone. For example, some bigplants were replaced by the small ones appeared in the Yellowstone due to theopen and shaded lands. Another example is that it was a better place for certainseeds thanks to the high level of the heat. This point directly contradictswhat the passage indicates.
Second, the reading passage states that thefire was a destruction of habitats and the disruption of the food chain. Theprofessor, however, stated that the population had already recovered, and createdsome ideal habitats for the small animals such as rabbits and hares. Moreover,since the rabbits and hares began to live there, the predators who lived onthem came to live in the Yellowstone, too. Therefore, certain food chain wasstronger than before. This is another point where the listening opposes thereading passage.
Third, quite different from what had beenstated in the reading passage, the lecturer said that the fire in 1988 wasquite unusual and it did not happen every year. Moreover, the massive fire was causedby the low rain fall and the strong wind, which would not occur again. Besides,the visitors still come back to the Yellowstone next year and each year after that.This point refutes the view stated in the reading passage.