Rivers and Lakes

Lowland Britain

Lowland Britain offers a striking contrast in many ways. Though so much less rugged, there are few parts where level land is uninterrupted by hills. One of the most extensive plains in the British Isles is in the English Midlands, consisting of river valleys and plains interspersed with scattered hills. It is the Midland Plain, which is best described as an undulating lowland rarely rising above 100 metres. To the north of it are the Pennines, to the south the Thames Basin, to the east East Anglia and to the West the Welsh Borderlands.

Another important plain in Britain is the London Basin in South East England. The master stream of the basin is Britain's second longest river, the Thames, which enters the region from the west. The Hampshire Basin includes a wide plain area of central southern England.

The geographical region described as the Lancashire and Cheshire Plain, includes the lowlands to the west of the Central and Southern Pennines. The Lowlands themselves are linked to the Midland Plain by a broad gap between the Welsh mountains and the Pennines, known as the Midland Gate. In Yorkshire, along the eastern edge of the Pennines lies the extensive Yorkshire Low­land.

The chief characteristic of East Anglia is its low relief with few hills, the area is mainly founded on chalk.

There is a fairly wide network of rivers in the British Isles, though generally short in length and navigable but in their lower reaches, especially during high tides. Mild maritime climate keeps them free of ice throughout the winter months.

In the Middle Ages, river transport played a majorrole in the British internal transport system, and all the large towns of the time were situated on navigable rivers. But since the beginning of the nineteenth century the waterways, including numerous canals, have steadily declined in importance, and many have fallen into disuse.

The drainage map of the British Isles seems to containno very clear pattern. The largestriver of GreatBritain, the Severn (350 km),for example,follows aparticularly puzzlingcourse. After rising on the slopes of Plynlimmon, in central Wales, it flowsat firstnorth-eastwards, but later turns sharplythroughthe Ironbridge gorgeand thenruns southwards and south-westwards to the Bristol Channel. The coursesof the Trent (274 km) and the upper Thames (346 km) also show many changes of direction.Many of the largestrivers in Scotland, suchas the Tweed, Forth, Dee and Spay, draindirectly to the NorthSea.Scotland's longest river, theRiver Tay, some 170 km long,alsofollows this course. Among other importantrivers, which flow eastwards, to the NorthSea, are the rivers Trent, Tyne, Tees, Humber, Ousein England.

A number of streams flow down to the west coast, to the Irish Sea, including the Clyde in Scotland, the Eden, Ribble, Mersey and the Severn. A few small rivers flow to the English Channel.

There are manyrivers in Ireland. They are short but navigable due to an abundant and even distribution of precipitation throughout the year. The longest river of the British Isles is the River Shannon (384 km), flowing from north to south of Ireland. Among other more or less important rivers are the Foyle, flowing to the north, the Lagan, Boyne. Liffey, Slaney -to the east, the Barrow and the Blackwater - to the south.

Most of the British lakes are in part the resultof glacial erosion and in part due to chemical solution of the underlying limestone. There is a host of small winding lakes in Scotland, in Cumbria and in Ireland.

The largest lake in Great Britain and the biggest inland loch in Scotland is Loch Lomond, covering a surface area of 70 square km, although the longest lake is Loch Ness (56 square km) which also has the greatest volume of water. In England the largest lakeis Lake Windermere (the Lake District) with a surface area of 15 square km.

The largest fresh water lake in the British Isles is Lough Neagh in Northern Ireland (381 square km).

The Quaternary glaciatlon has further modified the river patterns in many areas. This is especially true of central Ire­land, where the uneven surface of the drift cover has led, as in the basin of the Shannon, to much bad drainage, many peat bogs and numerous large lakes, such as Loughs Ree and Derg.

QUESTIONS:

1. Briefly outline the main featuresof the physical geography of the British Isles.

2. Describe the relief features of England, referring to mountainous areas.

3. Examine the relief features ofWales.

4. Describe the varied relief features of Scotland.

5. Describeand account for the main relief characteristicsofIreland.

6. Describe the major plains of lowland Britain.

7. Give an account of the drainage features of the British Isles, their chief rivers and lakes.

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