First,the spotted owl was threatened by logging in the Pacific Northwest．Now it's in danger from a new enemy,the barred owl．Barred owls have been moving to the Northwest from the eastern part of the United States．Stan Sovern has studied spotted owls．Now when he calls for spotted owls,barred owls are starting to appear．Sovern threw a mouse on the ground,and a barred owl grabbed it.
Scientists have learned that spotted owls start to vanish when barred owls come．Some barred and spotted owls have mated and produced hybrid babies．One spotted owl was killed by a barred owl.
Professor Ned K．Brown of the University of California-Berkeley says,"In some areas of Washington,the barred owls moved into very dense,deep woods．The same kind of woods that arc opened up,or destroyed by logging,that adversely influences the spotted owls."
Ten years have passed since the federal government began protecting the spotted owl．Loggers were forced to limit logging on seven million acres of government land．No one is sure how the arrival of the barred owls will impact laws that protect spotted laws．The barred owls like to live in the deep forests where loggers like to cut down trees．The barred owls will likely keep migrating to the Northwest.
Logging was greatly reduced__.
A、in the northeasten United States
B、on seven million acres of public land
C、two decades ago
D、to save the barred owls
【正确答案】：B
【题目解析】：根据文章描述，首先斑点猫头鹰因太平洋西北部的伐木活动而受到威胁。接着提到，现在斑点猫头鹰正面临一个新的敌人——横斑猫头鹰。横斑猫头鹰从美国东部迁移到西北部。文章中还提到，自从联邦政府开始保护斑点猫头鹰以来，已经过去了十年。伐木工人被迫在政府拥有的七百万英亩土地上限制伐木活动。
接下来，我们逐一分析选项：
A. 在美国东北部——文章并未提及美国东北部的情况，故A选项错误。
B. 在七百万英亩的公共土地上——这与文章中提到的“伐木工人被迫在政府拥有的七百万英亩土地上限制伐木活动”相符，故B选项正确。
C. 二十年前——文章提到的是“自从联邦政府开始保护斑点猫头鹰以来，已经过去了十年”，而非二十年，故C选项错误。
D. 为了拯救横斑猫头鹰——文章主要关注的是斑点猫头鹰和横斑猫头鹰对栖息地的竞争，并未提及拯救横斑猫头鹰的动机，故D选项错误。
因此，正确答案是B，即在七百万英亩的公共土地上，伐木活动被大大减少了。
First,the spotted owl was threatened by logging in the Pacific N
- 2024-11-09 06:34:15
- 英语（专升本）