问题 单项选择题

城市污水不经过处理排入水体后,由于氮磷钾含量增加,藻类繁殖,溶解氧减少,鱼类死亡,这类污染一般称之为( )。

A.有机污染
B.生物污染
C.热污染
D.富营养化污染

答案

参考答案:D

解析:[试题解析] 天然水体中由于过量营养物质(主要是指氮、磷等)的排入,引起各种水生生物、植物异常繁殖和生长,这种现象称作水体富营养化。过量营养物质主要来自于农田施肥,农业废弃物、城市生活污水和某些工业废水。

单项选择题

阅读下面短文,掌握其大意,然后从21—40各题所给的四个选项(A、B、C和D)中,选出最佳选项,并在答题纸上将该选项标号涂黑。

During the war,my husband was stationed at an army camp in a desert in California.I went to live there in order to be 21  him. I hated the place .I had never  22  been so unhappy . My husband was ordered out on a long-term duty,and I was left in a tiny shack(棚屋) alone. The heat was  23  -almost 125 0F even in the shade of a cactus(仙人掌)。 24  a soul to talk to . The wind blew non-stop ,and all the food I ate ,and the evry air I breathed,were  25   with sand , sand , sand !

I was so sorry for myself that I wrote to my parents. I told them I was  26   and coming back home.I said I couldn’t stand it one minute longer. I  27  be in prison! My father answered my  28  with just two lines-two lines that will always sing in my  29  - two lines that completely changed my life :

Two men looked out from prison bars

One saw the mud ,the other saw the stars

I read those two lines  30   I was ashamed of myself. I made up my mind I would find out what was good in my present  31  ; I would look for the stars

I made friends with the natives,and their  32  amazed me. They gave me presents of their favorite artworks which they had  33  to sell to toueists . I studied the delightful forms of the cactus .I watched for the desert sunsets,and  34  for seashells that had been left there millions of years ago when the desert had been an ocean  35 

What brought about this  36   change in me ? The desert hadn’t changed , 37   I had .I had changed my  38   And by doing so ,I changed an unhappy experience into the most amazing  39  of my life . I was excited by this new world that I had dicovered I had looked out of my self-creatded prison and  40   the stars

33()

A.refused

B.failed

C.managed

D.happened

判断题