People and lakes

There are tens of millions of lakes on the Earth. Lakes are a gift of Nature and a source of fresh water for humans, animals, plants and many species of fish. There are lakes rich in therapeutic mud or table salt but the real wealth of lakes is the beauty we enjoy.

Unlike dynamic rivers, lakes, for the most part, are settling tanks: once contaminated, they stay so indefinitely. Though outflowing rivers may drain lakes of some of their contaminants, about 60 per cent of the pollution is retained. In deep lakes, toxic substances may settle into the silt, whereas shallow waters are warmed by the sun to the bottom and thoroughly agitated in summer. A poisoned lake ages quickly.

Industrial wastes, harmful farming practices and lakefront highways often pollute lakes and its inflowing rivers. Among the most famous are Lake Sevan, Lake Ladoga and Lake Geneva. Some of the Great Lakes located between the United States and Canada are dangerous to swim in. They need saving.

There are some international programmes to save lakes. It has become clear that not only human activity, such as industry, agriculture, tourism and road construction but also the state of the atmosphere, solar activity and tectonics should be taken into consideration.

Russian scientists actively cooperate with researchers from Austria, the USA, Sweden, Finland and some other countries. The European countries, for example, have agreed to reduce the sulphur dioxide exhausts by 30 per cent.

1. Find the meaning of the following words (in the dictionary):

gift n; species n; therapeutic mud; wealth n; settling tanks; contaminate v; contaminant n; outflowing rivers; inflowing rivers; pollution n; pollute v; retain v; toxic substance; silt n; shallow waters; bottom n; agitate v; poison v; wastes n; harmful a; highways n; dangerous a; save v; solar activity; to take into consideration; cooperate v; reduce v; sulphur dioxide exhausts.

2. Read text A and answer the questions:

1. What kind of lakes do you know?

2. What’s the difference between a lake and a river?

3. What lakes need saving?

3. Find in the text the information about lake pollution and translate it into Russian.

4. Give the English equivalents of:

дар природы; истинное богатство озер; отстойник; загрязнять; загрязнитель; токсичные (ядовитые) вещества; дно; ил; промышленные отходы; вредная сельскохозяйственная деятельность; реки, впадающие в; реки, вытекающие из; опасный; спасать; уменьшить выбросы углекислоты; ученые; исследователи; сотрудничать; нужно принять во внимание.

Text B

Baikal’s pure Water

Each lake and every sea has its own legends, but Baikal, the great lake in Eastern Siberia, probably has the greatest number.

Baikal has a tremendous amount of water in its vast basin. Its depth in some places exceeds 1.5 kilometres, and its length is nearly 650 kilometres.

Baikal is like a long, deep sabre slash in the earth’s flesh. It has neither northern nor southern shore. Likewise, there are really only two seasons on Baikal – the one when the water is open, and the other when it is covered with ice.

The water in the lake is constant, both in composition and in temperature. The greatest annual temperature drop in water exceeds 6 – 8 ⁰C. Baikal water never becomes warmer than +12 ⁰C, with the exception of the lagoons, of course.

Seawater differs in colour, so that some of the seas were called “Black”, ”White”, “Yellow”, etc. Baikal’s water has its own colour – pale blue.

Learned limnologists cannot supply an absolutely correct explanation for the blue colour of the lake’s water. Many refer to its high oxygen content.

The unique fauna and flora make Baikal a real gem in the crown of Russian nature. Its coastline is a settled area, populated by thousands who live in the local towns and villages. Enterprises have been built in its littoral zone, which spreads for nearly 650 kilometres along its coast. Therefore, the task of preserving the lake is far from simple.

5. Find the meaning of the following words (in the dictionary):

pure a; probably adv; tremendous a; amount n; vast basin; depth n; sabre n; slash n; flesh n; shore n; likewise adv; cover v; composition n; annual a; exceed v; exception n; lagoon n; pale a; limnologist n; explanation n; refer v; oxygen content; unique a; gem n; crown n; coastline n; settled area; enterprise n, littoral a; spread v; preserve v.

6. Read text B and answer the questions:

1. How much water is there in Baikal?

2. What kind of water does the lake have?

3. Why is Baikal a unique lake?

7. Find in the text the information about Baikal’s water characteristics and translate it into Russian.

8. Say if these sentences are true or false. If false, correct them:

1. Baikal’s water has its own colour – dark blue.

2. There are no big enterprises in the littoral zone of the lake.

3. The task of preserving Baikal is difficult.

9. Give the Russian equivalents of:

a tremendous amount of water; vast basin; depth, length; annual temperature drop; to exceed; with the exception of; pale blue; an absolutely correct explanation; high oxygen content; unique fauna and flora; its coastline; a settled area; enterprises; littoral zone; to spread; the task of preserving the lake.

Text C