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.

　　35、The author seems to be mainly concerned with most fisheries’

　　[A] management efficiency

　　[B] biomass level

　　[C] catch-size limits

　　[D] technological application.

　　[答案] B

　　[解题思路]

　　本文主要就是围绕着“海洋生物总量”这个话题展开的，文中多次出现了“biomass”这个词，因此。B为正确答案是显而易见的。B、C、D选项都只是文章涉及到的几个小方面，无关大局。

　　[题目译文]

　　作者看起来最关心大多数浴场的

　　[A] 管理效率

　　[B] 生物量水平

　　[C] 捕鱼量的限制

　　[D] 技术的使用