问题 选择题

下表为三江海地区不同生态系统的土壤侵蚀量和保持量,表中的“潜在侵蚀量”, 为完全没有植被时的理论侵蚀量,土壤保持量为潜在侵蚀量与现实侵蚀量之差。表中对各生态系统同时列出了的总量(单位:104t/a)与单位面积量单位:t/hm2·a )。回答下列各题。

小题1:下列推断正确的是

A.高寒草甸土壤保持总量最大是因其土壤保持能力最强

B.高寒草原现实侵蚀量最大是因其分布面积最大

C.高寒荒漠草原单位面积现实侵蚀量最小说明面积最小

D.沼泽的分布面积约为灌丛面积的两倍小题2:三江源水平带谱自东向西的一般分布规律为

A.山地森林、高寒草原、高寒灌丛草甸、高寒草甸、高寒荒漠

B.高寒荒漠、高寒草原、高寒草甸、高寒灌丛草甸、山地森林

C.山地森林、高寒草原、高寒荒漠、高寒草甸、高寒灌丛草甸

D.山地森林、高寒灌丛草甸、高寒草甸、高寒草原、高寒荒漠

答案

小题1:D 

小题2:D

题目分析:

小题1:读表格,根据材料内容分析,高寒草甸土壤保持总量最大,是因为潜在侵蚀总量也最大,所以不是因其土壤保持能力最强 ,A错。高寒草原现实侵蚀量最大,与其分布面积大有关,但它的分布面积可以根据堆存侵蚀单位面积量计算出不是最大 ,B错。高寒荒漠草原单位面积现实侵蚀量最小,说明面积小,但与旱地相比,不是最小 ,C错。根据潜在侵蚀总量与潜在侵蚀单位面积量可以计算出,沼泽的分布面积约为灌丛面积的两倍,D对。

小题2:三江源位于青藏高原地区,自东向西降水逐渐减少,植被变化与从沿海向内陆的变化规律相似,随着降水减少,依次出现山地森林、高寒灌丛草甸、高寒草甸、高寒草原、高寒荒漠等植被,D对。A、B、C错。

填空题
阅读理解

Self-employed private physicians who charge a fee for each patient visit are the foundation of medical practice in the United States. Most physicians have a contract relationship with one or more hospitals in the community. They send their patients to this hospital, which usually charges patients according to the number of days they stay and the facilities(operating room, tests, medicines that they use). Some hospitals belong to a city, a state or, in the case of veteran's hospitals, a federal government agency. Others are operated by religious orders(教会) or other non-profit groups.

Some medical doctors are on salary. Salaried physicians may work as hospital staff members, or residents, who are often still in training. They may teach in medical schools, be hired by corporations to care for their workers or work for the federal government's Public Health Service.

Physicians are among the best paid professionals in the United States. In the 1980s, it was not uncommon for medical doctors to earn incomes of more than $ 100 000 a year. Specialists, particularly surgeons, might earn several times that amount. Physicians list many reasons why they deserve to be so well rewarded for their work. One reason is the long and expensive preparation required to become a physician in the United States. Most would be physicians first attend college for four years, which can cost nearly $ 20 000 a year at one of the best private institutions. Prospective physicians then attend medical school for four years. Tuition alone can exceed $ 10 000 a year. By the time they have obtained their medical degrees, many young physicians are deeply in debt. They still face three to five years of residency(实习阶段) in a hospital, the first year as an apprentice physician. The hours are long and the pay is relatively low.

Setting up a medical practice is expensive, too. Sometimes several physicians will decide to establish a group practice, so they can share the expense of maintaining an office and buying equipment. These physicians also take care of each other's patients in emergencies.

Physicians work long hours and must accept a great deal of responsibility. Many medical procedures, even quite routine ones, involve risk. It is understandable that physicians want to be well rewarded for making decisions which can mean the difference between life and death.

1. According to the passage, it is very unlikely that an American hospital is owned by _______.

A. a church     B. a corporation     C. a city         D. a state

2. The expenses for becoming a doctor are spent on _______.

A. schooling and retraining          B. practice in a hospital

C. facilities he or she uses            D. education he or she receives

3. According to the passage, how long does it take for a would-be physician to become an independent physician in the USA?

A. About seven years.                  B. Eight years.

C. Ten years.                               D. About twelve years.

4. Sometimes several physicians set up a group medical practice mainly because _______.

A. there are so many patients that it is difficult for one physician to take care all of them

B. they can take turns to work long hours

C. facilities may be too much of a burden for one physician to shoulder

D. no one wants to assume too much responsibility

5. Which of the following statements could fully express the author's view towards physicians’ payment in the USA?

A. For their expensive education and their responsibility, they deserve a handsome pay.

B. It is reasonable for physicians to have a large income because their work is very dangerous.

C. Physicians should be better paid because they work long hours under bad conditions.

D. Physicians have great responsibility, so it is understandable that they should be well rewarded.