专业英语复习资料1

2.

Population

distribution

means

the

pattern

of

where

people

live.

Population

density

is

a

measurement of the number of people in an area. It is an average number. Population density

is

calculated by dividing the number of people by area. Population density

is usually shown as the

number of people per square kilometer.

人口分布是人们居住在哪里的模式。

人口密度是某区域人口数量的一个度量，

它是个平均值。

人口密 度由人口除以面积得到，人口密度常常用没平方公里的人数来表示。

3.

Humans

probably

first

experienced

harm

from

air

pollution

when

they

built

fires

in

poorly

ventilated caves. Since then we have gone on to pollute more of the earth's surface. Until recently,

environmental pollution problems have been local and minor because of the Earth's own ability to

absorb and purify minor quantities of pollutants. The industrialization of society, the introduction

of

motorized

vehicles,

and

the

explosion

of

the

population,

are

factors

contributing

toward

the

growing air pollution problem.

在通风很差的洞穴里生火可能是人类经历的最早空气污染危害 。

从那时起我们污染了越来越

多的地球表面。

< br>由于地球自身有吸收和净化少量的污染物的能力，

因此直到最近环境污染问

题仍然是局部和次要的。

社会产业化、

机动车 使用，

人口爆炸都是导致空气污染日益严重的

因素。

4.

Negative

impacts

from

tourism

occur

when

the

level

of

visitor

use

is

greater

than

the

environment's

ability

to cope with

this

use within

the

acceptable

limits

of change.

Uncontrolled

conventional

tourism

poses

potential

threats

to

many

natural

areas

around

the world. It

can

put

enormous

pressure

on

an

area

and

lead

to

impacts

such

as

soil

erosion,

increased

pollution,

discharges

into

the

sea,

natural

habitat

loss,

increased

pressure

on

endangered

species

and

heightened vulnerability to forest fires. It often puts a strain on water resources, and it can force

local populations to compete for the use of critical resources.

当旅游者的使用超过环境处理这种可接受变化的能力时，

旅游就会带来负面影响 。

不受控制

的常规旅游对世界各地许多自然区域构成潜在的威胁 。

它使区域面临巨大的压力，

并导致水

土流失、

污染加剧、

污物入海、

自然生 境丧失、

濒危物种压力增大以及森林火灾脆弱性增加。

它往往导 致水资源紧张，迫使当地居民争夺关键资源的使用权。

5. The greenhouse effect is a naturally occurring process that aids in heating the

Earth's surface

and

atmosphere. It

results

from

the

fact

that

certain

atmospheric

gases,

such

as

carbon

dioxide,

water

vapor,

and

methane,

are

able

to

change

the

energy

balance

of

the

planet

by

absorbing

longwave

radiation

emitted

from

the

Earth's surface.

Without

the

greenhouse

effect

life

on

this

planet

would

probably

not

exist

as

the

average temperature

of

the

Earth would

be

a chilly

-18°

Celsius, rather than the present 15°

Celsius.

温室效应是有助于加热地表和大气的自然过程。

它源于这一事实

——

某些气体，

如二氧化碳、

水蒸气和甲烷，

能够通过吸收地表的长波辐射而改变地球能量平衡。

没有温室效应，

地球上

的生命就不可能存在，因 为地球的平均温度将是寒冷的

-18

℃，而不是目前的

15

℃。

6.

In

the

last

few centuries,

the

activities

of

humans

have

directly

or

indirectly

caused

the

concentration of the major greenhouse

gases to increase. Scientists predict that this increase

may enhance the greenhouse effect making the planet warmer. Some experts estimate that the

Earth's

average

global

temperature

has

already

increased

by

0.3

to

0.6°

Celsius,

since

the

beginning of this century, because of this enhancement. Predictions of future climates indicate

that by the middle of the next century the Earth's global temperature may be 1 to 3°

Celsius

higher than today.

< br>在过去几个世纪，人类活动直接或间接导致主要温室气体浓度增加。科学家预测，温室

气体浓度增加会加强温室效应导致地球变暖。一些专家估计，自本世纪初以来，由于温

室效应增强引起全球平均气温已经增加了

0.3

~0.6< /p>

℃。未来气候预测表明到下个世纪中

叶，地球气温可能比现在高< /p>

1~3

℃。

7.

Hydrology

is

the

science

that

studies

the

Earth's

water

molecules

and

their

movement

through the hydrologic cycle. The Earth and its various abiotic and biotic systems are greatly

influenced by water. Water is essential for life and plays an important role in atmospheric and

lithospheric processes.

水文学是研究地球上的水分子及其在水循环中的运动的科学。

水 极大地影响着地球及地

球上的各种生物和非生物系统。水是生命所必需的，在大气圈过程 和岩石圈过程中扮演

重要角色。

8. There are many hidden costs to tourism, which can have unfavorable economic effects on

the host community. Often rich countries are better able to profit from tourism than poor ones.

Whereas

the

least

developed

countries

have

the

most

urgent

need

for

income,

employment

and general rise of the standard of living by means of tourism, they are least able to realize

these benefits.

旅游有很 多潜在成本，会对发展旅游的地区经济造成不利影响。通常，富裕国家比贫穷

国家能够更 好地从旅游业中受益。

而最不发达国家最急切需要通过旅游发展提高经济收

入、就业和总体生活水平，他们又最缺乏能力去实现这些利益。

9. Some scholars define a primate city as one that is larger than the combined populations of the

second

and

third

ranked

cities

in

a

country.

This

definition

does

not

represent

true

primacy,

however, as the size of the first ranked city is not disproportionate to the second.

一些学者定义在一个国家里人口比排名第二、

第三城市的总人口 还多的城市为首位城市。

这

个定义并不代表真正的首要地位，而 是指排名第一的城市的规模与排名第二的城市不相称。

10.

While

the

world's

population

tripled

in

the

20th

century,

the

use

of

renewable

water

resources has grown six-fold. Within the next fifty years, the world population will

increase

by

another

40

to

50

%.

This

population

growth---coupled

with

industrialization

and

urbanization---will

result

in

an

increasing

demand

for

water

and

will

have

serious

consequences on the environment.

20

世纪，世界人口增加了两倍，可再生水资源用量则增长了

6

倍。在未来五十年里，世界

人口将再增加