题目

什么措施能提高一个生态系统的稳定性？ A  减少捕食者和寄生物的数量    B  使生产者和消费者的数量保持平衡 C  增加物种数目                D  限制一个演替系列的演替进程 答案：C 解析: C正确，因为生态系统的稳定性与物种数目的多少呈正比关系，即物种数目越多生态系统就越稳定，这是因为物种数目越多，生态系统中的能流路径和物质循环的渠道就越多，每个物种所起的作用就越小，部分物种的消失或绝灭对整个生态系统稳定性的冲击就越小，也就是生态系统的抗干扰能力用所给词的适当形式填空。【1】Peter always ___________ (play) the piano on Sundays.【2】___________ (do) she like watching TV in the evening?【3】What's your ___________ (father) hobby?【4】___________ (they) hobbies are singing and dancing.【5】Look! The baby is ___________ (smile).【6】My sister likes ___________ (make) dolls.【7】I have many picture ___________ (card). They're so ___________ (colour).【8】—What are you ___________ (do)?—I'm ___________ (cook) meals.