Lesson 4. Waterbodies.

Water is collecting and moving downhills in small, tiny streams which are called RILLS. They join with other rills to form STREAMS which then meet other streams to become a RIVER. A river is a stream of water which flows into an ocean, sea, lake or some other body of water. As it flows through the land, a river carries away much fine rock material. All streams flowing into a river are its BRANCHES, or TRIBUTARIES.

A large river with all its tributaries forms a RIVER SYSTEM and all the land that is drained by such a river system is a RIVER BASIN (the area from which the rainfall water gets into the main river). The line which separates one river (DRAINAGE) basin from the other is called a DIVIDE, or WATERSHED.

The arrangements of streams within a drainage basin reflects local conditions of climate, geology and relief. On the other hand, moving water influences the relief as it produces erosion. It may be VERTICAL or LATERAL (HORIZONTAL). In upland areas most erosion takes place vertically on the BED OF THE RIVER. WATERFALLS or RAPIDS may form where a stream plunges into a deep valley formed by a glacier in the Ice Age, where it crosses a FALT LINE or where it flows from hard to soft rocks. Erosion in upland areas forms valleys which are narrow and steep-sided. If downward erosion is very rapid or the valley sides are very hard, a GORGE with almost vertical sides may result. In lowland areas where the river is nearer to the sea-level it cannot erode downwards very much. Vertical erosion is slower and the effects of lateral erosion are more easily seen. Most lateral erosion takes place where a river is swinging from side to side or MEANDERING. The wide flat valley floor cut by the MEANDERS as they move down the valley is called a FLOOD PLAIN OF A RIVER.

A river usually RISES in the mountains or in some other upland areas. The SOURCE of a river can be a spring, lake, etc. (See Glossary for “Parts of the river”). The sources of river’s FEEDING depend on climate and relief of the area where the rivers flow across (rainfall, snowfall, glaciers, etc.). Rivers are useful in many ways: they lower the surface of the land in some places and build it up in others, the running water can be used to turn machinery at a waterfall or at rapids, where the force of running water is strong. Sometimes people place a dam in a river in order to get a fall of water to furnish power. Rivers are also used for transportation, for travel and for recreation. And finally they can furnish food (e.g. fish) and water supply (water for drinking, for crops – that’s for irrigation, etc.).

A LAKE is a body of water surrounded by land. Any natural hollow in the ground may become filled with water and form a lake. Lakes may be of different origins, e.g. volcanic lakes, lakes formed by glacial erosion, etc. Lakes may also be found at all parts of a river’s course and may often be looked upon as widenings of the river. A lake may have several streams flowing into it, known as INLETS, but the water flows out only at the lowest point, or OUTLET. Lakes which have inlets and outlets are called DRAINED and are generally FRESH-WATER lakes. There are lakes that have many inlets, but no outlets, they are called DRAIN

LESS, or UNDRAINED, and the water in such lakes is usually SALTY. A smaller lake that has no outlet is called a POND.

Lakes are very important. The large ones are used as trade routes, they furnish food and water supply for drinking and irrigation, some of them are salt supply. Most of the lakes are used for recreation.

All lakes slowly become filled with SILT, plants spring up in the shallower parts until finally the lake is almost gone. In its place we have a soft wet SWAMP. Swamps are also often found beside streams or along the shores of large bodies of water. Swamps (BOGS, MARSHES) are usually waste land, unfit for farming, but in many areas they are successfully DRAINED and used.

Waterbodies of Great Britain.

Great Britain is rich in water resources. Practically everywhere, except some south-eastern regions, rainfall exceeds EVAPORATION, that’s why there are a lot of FULL-FLOWING rivers there. The rivers of Great Britain are not very long, but they are deep. The chief rivers are the Severn and the Thames. Although rivers are not much used for navigation, they supply many cities and towns including London with fresh water. Ports on the Thames, Newcastle-upon-Tyne and Glasgow are TIDAL and the rise and the fall of the tide help to keep the mouths of the rivers from silt. Rivers are often connected with each other as the Severn and the Thames with CANALS which used to be very important for economy of the country. Most of the rivers are used for recreation. The Thames is the main river of the South (and, as it was mentioned, of Britain as a whole). It rises in the Midlands of England. In 1958 a special board definitively identified the source of the Thames as a spring which flows out of a meadow near the village of Coates. The Thames is not the longest, but the deepest river of Great Britain. It flows through London and makes it a large port, though the city is 84 km away from the sea. The river is 338 km long.

The Severn is a river in England and Wales. It rises in North Wales and flows through central England to the Bristol Channel west of Bristol. It’s the longest river in Britain, it’s 354 km long. It has a tidal wave (the river is tidal) like the Thames.

Other important rivers are: the Mersey, the Ouse, the Humber, the Trent, etc.

Among the lakes of England the most famous are the lakes of the Lake District. They are formed by glacial erosion. As for the rest of England – in the lowland part of it there are no large and important natural lakes, but there are many artificial lakes (reservoirs) there.

The important rivers of Scotland are: the Tay, the Forth, the Tweed, the Clyde, etc. The first three of them flow into the sea on the east, and the Clyde flows into the Atlantic. All except the Tweed widen out into great estuaries to which they give their names: the Firth-of-Tay, the Firth-of-Clyde, etc.

The Tweed runs for a hundred miles through the Border country (that is the region which lies between Edinburgh, the capital of Scotland, and the English counties) and marks the boundary between Scotland and England. The waters of the firths penetrate so far inland that there is a distance of only 40 miles between Glasgow and the Firth-of-Clyde.

The river Forth is famous for its two bridges which cross the estuary, the Firth-of-Forth. The first one, built in the late 19^th century west of Edinburgh, was generally regarded as one of the world’s greatest engineering feats. The bridge has a length of 521 m and needs constant painting (because of this, saying that some task “is like painting the Forth Rail Bridge” means that it is an endless task or involves unending work). The second bridge, that is the Forth Road Bridge, built in the mid-20^th century just west of the Rail Bridge. It is one of the longest suspension bridges in the world – 1,006 metres.

The Clyde is the most important river of south-west Scotland, famous for the industries that have developed on its banks and its estuary, especially where it flows through Glasgow.

There are a lot of lakes called “lochs” in Scotland, the most important of them are the Loch Ness and the Loch Lomond lakes. The Loch Ness is a long lake in Northern Scotland. It’s probably Britain’s best-known lake, because of the so-called Loch Ness monster – a large prehistoric creature said to be living in the deep waters of the lake, but as yet, in spite of various “sightings”, not scientifically proved to exist. The popular name of the Loch Ness monster is Nessy (Nessie). As for Loch Lomond, it is the largest lake in Scotland and in the whole of Britain. The lakes of Scotland are mostly formed by glacial erosion.

Speaking of Wales, we usually mention the Severn, the Wye and the Dee. They are short, but deep. As for Northern Ireland, we should mention the river Bann and the largest lake of the archipelago – the Loch Neagh.

GLOSSARY:

alluvial plain аллювиальная равнина

be … meters (km) long, иметь длину, ширину,

wide, deep, etc. глубину … метров (км)

branch (tributary) приток реки

to take a branch (tributary) принимать приток

canal канал (искусственное

сооружение, ср. channel)

divide (watershed) водораздел

drain осушать, собирать воду,

стекать

erosion эрозия

lateral (horizontal) erosion горизонтальная эрозия

vertical erosion вертикальная эрозия

evaporation испарение

evaporate испарять, испаряться

falt line линия разлома

feeding of a river питание реки

be fed by питаться (о реке)

flood затоплять, заливать

flood, n. наводнение

flow (across, through) течь, протекать

flow into впадать

flow north (south, etc.) течь на север (юг, и т.д.)

flow out of вытекать

flow, n. (current) течение

freeze (froze, frozen) замерзать

gorge ущелье

irrigate орошать

irrigation орошение

lake озеро

artificial lake = reservoir = искусственное озеро,

man-made lake водохранилище

fresh-water lake пресное озеро

salt lake соленое озеро

inlet of a lake река, впадающая в озеро

outlet of a lake река, вытекающая из озера

drained lake сточное озеро

undrained = drainless lake бессточное озеро

meander меандрировать, извиваться

meander, n. меандр

meandering меандрирующий, извилистый

navigable судоходный

navigation навигация, судоходство,

мореплавание

rapid порог (о реке)

rise брать начало (о реке)

river река

river (drainage) basin речной бассейн

river system речная система

Parts of the river: Части реки:

source of a river исток реки

mouth устье

delta дельта

estuary эстуарий

flood plain пойма

course (the upper, middle and течение (верхнее, среднее,

low course) нижнее течение)

river-bed русло

silt осадок, наносы, ил

stream поток, ручей, река,

течение, рукав реки

swamp (bog, marsh) болото

tides приливно-отливные явления

the rise of the tide прилив

the fall of the tide отлив водопад уровень воды

waterfall водопад

water level уровень воды

ASSIGNMENTS AND EXERCISES:

1. Study the text about waterbodies and the Glossary.

2. Give the definitions of the following terms: река, озеро, приток, речная система, речной бассейн, водораздел.

3. Explain the terms in English: пороги, водопады, вертикальная и горизонтальная эрозия, меандрировать, сточное и бессточное озеро, болото, пруд, канал.

4. Trace on your contour maps all the rivers and lakes mentioned. Make sure you can show them on the map.

5. Name the main parts of the river.

6. Study the text about the main rivers and lakes of Great Britain. Answer the questions:

1. Why is Great Britain rich in water resources?

2. Are there any places in the country where evaporation is higher than rainfall? Show them on the map and name the reasons.

3. Few rivers in Great Britain are used for navigation. Explain the reasons and show navigable rivers on the map.

4. London is situated 84 km away from the Thames’s mouth. Why can it be used as a port?

5. Name the most important rivers of England, Scotland, Wales and Northern Ireland.

6. Find some additional information about the lakes of Great Britain and make reports on the topics:

1. British lakes.

2. The Loch Ness and its monster.

3. The Lake District.

2. Make a report about any river mentioned in the lesson. Describe it following the plan: the geographical position of the river, the place where it rises, the areas it flows across, its branches, the place, where it flows into, the feeding of the river, the regime of the river, cities and ports, situated on it, any interesting information about the river, etc.

3. Translate into English:

1. Всякая река имеет исток, т.е. место, где она берет свое начало.

2. Место впадения реки в другую реку, озеро или море называется устьем реки.

3. Реки, текущие по равнинной местности, имеют медленное течение и меандрируют.

4. Реки, протекающие в гористой местности, обычно имеют быстрое течение и образуют глубокие узкие ущелья с почти вертикальными стенками.

5. Всякое большое по площади замкнутое природное углубление на поверхности земли, заполненное водой, называется озером.

6. Почти на всей территории Великобритании, за исключением некоторых районов на юго-западе страны, количество осадков превышает испарение, в результате чего в стране густая сеть полноводных рек.

9. Read the text about the Kielder Water. What is the reservoir used for? Retell the text.