下列有关群落演替的叙述中，错误的是（）
A.群落演替主要有初生演替和次生演替两种类型
B.在群落演替过程中，不同时期群落中的优势种群会发生更替
C.人类活动对群落演替的影响与自然演替的方向、速度基本相同
D.裸岩上的演替可能经过裸岩一地衣一苔藓一草本一灌木一森林六个阶段
参考答案：C
解析：
演替主要有初生演替和次生演替，故A正确。群落演替过程中是优势种群的替代，故B正确。人类活动可以是群落按照不同于自然演替的方向和速度进行，故C错误。裸岩上的演替是初生演替有的依次会经历裸岩一地衣一苔藓一草本一灌木一森林六个阶段演替为森林，但有的不能成为森林，故D正确。 考点：本题考查演替相关知识，意在考察考生对知识点的识记掌握程度。
In real life, robots are mainly used in factories. They do many different jobs. Usually these jobs are too , difficult or boring for humans. Robots also help disabled people and people who cannot look after . For example, scientists are making a robot to help people. Now many of them have a dog to help them. The dog is called a guide dog. In the future, guide dogs might be robot dogs. One robot dog is called Meldog. It has wheels. It usually “walks” its owner. It is very clever. It knows the speed of its owner’s walk. Meldog talks to its owner by . The owner wears a special belt. This belt instructions to the owner from Meldog such as “Stop here”, “Turn left” and “Turn right”. In the United States, another of robot helps disabled workers. This robot, called Kilroy, helps disabled computer operators. The robot the sound of its owner’s voice. It follows instructions such as “Turn the page” and “Make a cup of coffee”. Robots are also used in American . They can do simple jobs. For example, they shave (刮脸) patients and brush their teeth and take meals from the kitchen to patients’ rooms. It never gets lost this robot has a map of the hospital in its computer memory.
|