考研英語閱讀理解命題思路透析和真題揭秘(28)

2006年Text 3

　　When prehistoric man arrived in new parts of the world, something strong happened to the large animals; they suddenly became extinct. Smaller species survived, the large, slow-growing animals were easy game, and were quickly hunted to extinction. Now something similar could be happening in the oceans.

　　That the seas are being over-fished has been known for years what researchers such as Ransom Myers and Boris Worm have shown is just how fast things are changing. They have looked at half a century of data from fisheries around the world. Their methods de not attempt to estimate the actual biomass (the amount of living biological matter) of fish species in particular parts of the ocean, but rather changes in that biomass over time. According to their latest paper published in Nature, the biomass of large predators (animals that kill and eat other animals) inanes fishery is reduced on average by 80% within 15 years of the start of exploitation. In some long-fished areas, it has halved again since then.

　　Dr. Worm acknowledges that these figures are conservative, one reason for this is that fishing technology has improved Today's vessels can find their prey using satellites and sonar, which were not available 50 years ago that means a higher proportion of what is in the sea is being caught, so the real difference between present and past is likely to be worse than the one recorded by changes in catch sizes. In the early days, too, longlines would have been more saturated with fish. Some individuals would therefore not have been caught, since to baited hooks would have been available to trap them, leading to an underestimate of fish stocks in the past. Furthermore, in the early days of longline fishing, a lot of fish were lost to sharks after they had been hooked. That is no longer a problem, because there are fewer sharks around noise.

　　Dr. Myers and Dr. worm argue that their work gives a correct baseline, which future management efforts must take into account. They believe the date support an idea current among marine biologists, that of the "shifting baseline". The notion is that people have failed to detect the massive changes which have happened in the ocean because they have been looking back only a relatively short time into the past. That matters because theory suggests that the maximum sustainable yield that can be cropped form a fishery comes when the biomass of a target species is about 50% of its original levels. Most fisheries are well below that, which is a bad way to de business.

33. By saying these figures are conservative (line in ,paragragf-3), Dr worm means that
[A] fishing technology has improved rapidly
[B] then catch-sizes are actually smaller then recorded
[C] the marine bio mass has suffered a greater loss
[D] the date collected so far are pit pf date.

[答案] C

[解題思路]

　　本題要求判斷Worm博士說的"這些數據尚未保守"這句話的具體含義，其對應的信息是文章的第三段。該段第一句話后面的內容是對這句話內容的補充說明，指出現代漁業(yè)技術的改進、鯊魚的減少等因素都大大提高了捕魚率，正如該段所說的，"the real difference between present and past is likely to be worse than the one recorded by changes in catch sizes"（現在和過去的真正差距可能會比之前通過捕獲區(qū)記錄變化得到的數據更大）。也就是說，這些數據保守的原因在于實際的捕魚量可能比現有數據更大，即海洋動物總量損失的實際情況比現有數據顯示的結果更加嚴重，因此C選項為正確答案。A選項是解釋這句話的原因之一，但不是其含義。B選項的表述與文章意思相反。D選項認為這些數據已經過時，但數據保守并不意味著它已過時，文章中也沒有提到這一點，因此該選項錯誤。

[題目譯文]

Worm博士說"這些數字是保守的"（第三段第一行）這句話的意思是          。
[A] 捕魚技術得到了快速提高
[B] 捕魚量實際上沒有記錄的那么大
[C] 海洋生物量受到了更大的損失
[D] 迄今為止搜集到的資料已經過時