问题 问答题 简答题

野外采样土壤测量与水系沉积物测量有什么不同?

答案

参考答案:

水系:在采样点上下游5~10m内或垂直于流向取2~3个质量相等样品组合成1个样,要求取最新的表层物质。当表层受到人为污染时,则取较深层位。

土壤:

1)残坡积层一般取B层土,不在A层取样

2)外来物覆盖区,应穿透外来物取样。

3)在炎热多雨、化学风化强烈、元素在地表发生强烈淋溶时则应考虑加大取样深度。

4)水田区应穿过耕作层在残坡积层取样。

单项选择题 共用题干题
阅读理解

阅读理解。

     Tim Richter and his wife, Linda, had taught for over 30 years near Buffalo, New York-he in computers,

she in special education. "Teaching means everything to us," Tim would say. In April1998, he learned he

would need a heart operation. It was the kind of news that leads to some serious thinking about life's purpose.

     Not long after the surgery, Tim saw a brochure describing Imagination Library, a program started by

Dolly Parton' s foundation (基金会) that mailed a book every month to children from birth to age five in the

singer's home town of Sevier, Tennessee. "I thought, maybe Linda and I could do something like this when

we retire," Tim recalls. He placed the brochure on his desk, "as a reminder."

     Five years later, now retired and with that brochure still on the desk, Tim clicked on imagination library.

com. The program had been opened up to partners who could take advantage of book and postage discounts.

The quality of the books was of great concern to the Richters. Rather than sign up online, they went to

Dollywood for a look-see. "We didn't want to give the children rubbish," says Linda. The books-reviewed

each year by teachers, literacy specialists and Dollywood board members-included classics such as Ezra Jack

Keats's The Snowy Day and newer books like Anna Dewdney's Llama Llama series.

     Satisfied, the couple set up the Richter Family Foundation and got to work. Since 2004, they have shipped

more than 12,200 books to preschoolers in their in their area. Megan Williams, a mother of four, is more than

appreciative:"This program introduces us to books I've never heard of."

     The Richters spend about $400 a month sending books to 200 children. "Some people sit there and wait

to die," says Tim. "Others get as busy as they can in the time they have left."

1. What led Tim think seriously about the meaning of the life?

A. His death problem

B. His love for teaching

C. The influence of his wife

D. The news from the Web

2. What did Tim want to do after learning about Imagination Library?

A. Give out brochures.

B. Do something similar.

C. Write books for children

D. Retire from being a teacher.

3. According to the text, Dollly Parton is _____.

A. a well-known surgeon

B. a mother of a four-year-old

C. a singer born in Tennessee

D. a computer programmer

4. Why did the Richters go to Dollywood?

A. To avoid signing up online.

B. To meet Dollywood board members.

C. To make sure the books were the newest.

D. To see if the books were of good quality.

5. What can we learn from Tim's words in the last paragraph?

A. He needs more money to help the children.

B. He wonders why some people are so busy.

C. He tries to save those waiting to die.

D. He considers his efforts worthwhile.