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单选题英语四级

2017-05-18

第（35）题选

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K

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本文讲了光线照射对饥饿感和新陈代谢的影响，所以此处指光线照射、饥饿感和新陈代谢三者之间的“作用机制”，故选K。

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1 根据下面资料，回答题
A Logger's Lament
A. My father was a logger. My husband is a logger. My sons will not be loggers. Loggers are an endangered species,but the environmental groups, which so righteously protect endangered species in the animal kingdom, have no concern for their fellow human beings under siege.Loggers are a much misunderstood people, pictured as brutal rapists of our planet, out to denude it of trees and, as a result, of wildlife.
B. It is time to set the record straight. Loggers take great pride in the old growth trees, the dinosaurs of the forests,and would be sorry to see them all cut. There are in the national forests in Washington and Oregon (not to mention other states) approximately 8.5 million acres of forested land, mostly old growth set aside, never to be used for timber production. In order to see it all, a man would have to spend every weekend and holiday for sixty years looking at timber at a rate of more than one-thousand acres per day. This does not include acreage to be set aside for spotted-owl protection.
C. In addition to this amount of forested land never to be logged, the State of Washington forest Practices Act,established in 1973,specifies that all land that is clear-cut of trees must be replanted unless converted to some other use. As a tree farmer generally plants more trees per acre than he removes, more trees are being planted than are being cut. In the last twenty years in Clark County,Washington,alone,the Department of Natural Resources has overseen the planting of at least 15000 acres of previously unforested private lands.
D. The term logger applies to the person harvesting trees. A tree farmer is the one who owns the land and determines what is to be done with it. To a tree farmer, clear-cutting is no more than the final harvest of that generation of trees. The next spring ,he reforests the land. To the public, clear-cutting is a bad word. Does the public cry shame when a wheat farmer harvests his crop and leaves a field of stubble in place of the beautiful wheat?
E. In the Pacific Northwest, in five years, the nearly planted trees will grow taller than the farmer' s head ;in ten years, more than fifteen feet tall; and in twenty to thirty years, the trees will be ready for the first commercial harvest. The farmer then thins the trees to make room for better growth. In forty to fifty years, he will be ready to clear-cut his farm and replant again. Contrary to public opinion, it does not take three hundred years to grow a Douglas fir tree to harvestable age.
F. Tree fanning keeps us in wood products. We build with wood, write on paper, and even use the unmentionable in the bathroom. But in order to keep this flow of wood products available, we need to keep it economically feasible to grow trees. If we restrict the tree-farming practices because we do not like clear-cuts or because some animals might (and probably might not) become extinct, or we restrict markets for the timber by banning log exports or overtax the farmer,we are creating a situation where the farmer will no longer grow trees. If he cannot make money,he will not tree-farm. He will sell his tree farm so that it can grow houses. The land that grows trees is the natural resource; the trees are just a crop.
G. Legislation is constantly being introduced to take away the private property rights of tree farmers. They are beleaguered by the public, who believe that any forest belongs to the public. Who, after all,buys the land and pays the taxes? Who invests money in property that will yield them an income only once every twenty to thirty years? Would John Q. Public picnic in a farmer' s wheat field?
H. The tree farmer must have a diversified market. When there is a building slump in this country, it is vital to the industry to have an export market. Earlier recessions were devastating to tree farmers until markets were developed overseas. Some trees have little market value in the United States. The logs China and Korea bought in the late 1980s could not be sold here to cover the cost of delivery.
I. As to the wildlife becoming extinct,that is a joke that is not very funny. Animals thrive in clear-cuts better than in old-growth timber. Look at the Mount St. Helens blast area. Nature created an immense clearing and now deer, elk,and other wildlife are returning in numbers.Why? Because there is more food growing in an open area than under the tall trees. And as for the spotted owl, surely the 8.5 million acres set aside is enough to maintain quite a respectable owl population. Numerous recent observations show that the owl lives in second-growth timber as well as in old growth. In the Wenatchee National Forest there are more than two hundred fifty examples of spotted owls living in other than old-growth timber. The owl is a tool of the environmentalist groups to get what they want: the complete eradication of the species Logger.
J. Consider the scenic value of a preserved old-growth forest versus a managed stand of timber. In Glacier National Park, Montana, for example, which is totally untouched, one sees the old trees, the dead and dying trees, the windfalls crisscrossing the forest. In a managed forest, one sees the older stands with the forest floor cleared of the dead windfalls, leaving a more park like setting. In the younger stands, one sees the beautiful new trees with their brilliant greens thrusting their tops to the sky and, in the clear-cuts, before the new trees obscure the view, one sees the huckleberry bushes with their luscious-tasting berries, the bright pink of fire weed and deer and elk feeding. True environmentalists husband the land;they do not let the crops stagnate and rot. Tree farming
regenerates the trees and utilizes the product.
Tree farmers need an economical guarantee to keep the wood products markets run smoothly.

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2 The number that a logger plants trees is much larger than the number of trees removed.

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3 For the forestry, it is necessary to develop an export market in case of a building slump.

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