Research Results For 'Himalayas'

MOUNTAINS

Mountains are often classified according to their mode of formation: Fold
mountains; Block mountains; Residual mountains; Volcanic mountains.

High mountain chains such as the Himalayas, Andes, Alps, and Rockies are known as new fold mountain systems. The term 'fold' is a reference to the way in which such mountains have been formed. Throughout millions of years slow movements of the earth's crust have caused these
mountains to be raised. The movements which have resulted in mountain buildings were not, however, vertical uplifts. They were primarily horizontal movements, the effect of which was to cause the crust of the earth to 'wrinkle', in a similar way to which a tablecloth wrinkles if it is pushed along the table. The arched or upraised parts of the folds are known as anticlines and the troughs as synclines. These folds can vary greatly in size. Mountain building is undoubtedly due to some deep-seated cause. For a long period the most simple explanation was that folding was entirely due to the cooling and contraction of the earth, so that the crust, already cold and shrunken, had to wrinkle to fit itself to the still cooling and contracting 'core'. One of the objections advanced against this theory is that the amount of shrinking necessary to account for the Himalayas, Alps, etc., seems to be greater than the mere contraction of the earth would allow. While the theory of contraction cannot be completely rejected, serious consideration must be given to the more recent explanations of mountain building. For instance, Wegener suggests that mountain building may be due to the 'wrinkles' produced by the drifting of a continental mass, e.g. that the Alps were formed by the northward drift of the African continent towards the more stable blocks of Central Europe. As the African mass drifted slowly northward the zone between it and the European mass became narrower, and the land was raised into high ridges or folds. The raising of the Alps was accompanied by the formation of the deep trough which contains the Mediterranean Sea. The same hypothesis would account for the building of the Himalayas and the depression of the Indo-Gangetic trough by the northward drift of the Deccan mass.

During the physical history of the earth, mountain building appears to have proceeded more actively at some periods than others. Fold mountains are, therefore, not all of the same age. The newest group of fold mountains include the Himalayas, Alps, Rockies, and Andes. During an earlier period of folding (the Carboniferous) the Pennines, Appalachians, the Cape Ranges of South Africa, and the Dividing Range of Australia were uplifted. A still earlier period of folding accounted for the original mountains of Scotland and Norway, of which the present mountains are merely the worn down stumps. The older fold mountains, which have been subjected to the forces of denudation (such as the weather, rivers, glaciers, etc.) for long geological periods, are much lower and less rugged than the newer fold mountains. The term 'new fold' is applied to the mountain ranges which have been folded most recently, but they seem very old when their age in actual years is considered because they were uplifted many millions of years before historic time. Mountain building is a very long and slow process; and in the case of certain mountain chains, such as the Andes and the mountains of Japan, is probably still proceeding.

The new fold mountain systems of the world, except in such instances as the simple low folds of the Weald (South-east England), usually consist of high parallel ranges, the average height being well over 3000 metres. In the Himalayas' the highest peak rises to 8840 metres; in the Andes 7000 metres; in the Rockies 6000 metres; in the Alps to 4600 metres. Vast though these heights appear, the wrinkles of the earth's crust are only slight. The highest mountain in the world (Mount Everest) is about five miles high, so that on a globe of 40 cm, diameter it would protrude only 2.5 mm. Most of the active volcanoes are found in the neighbourhood of fold mountains, where the crust of the earth has been fractured during the process of folding. All around the Pacific Ocean there are many active and extinct volcanoes, as in New Zealand, the East Indies, Japan, and North, Central, and South America. Another belt of active volcanoes is associated with the fold mountains of the West Indies. The mountains of this type are characterised by ruggedness of relief in contrast to the smooth and rounded contours of mountain areas which have been subjected to weathering agents for long periods of time. This is obvious if pictures of the Alps and the Scottish Highlands are compared.

Mountains are effective climatic barriers, and the climates of regions on either side of a high mountain range are very different. For example, the coast lands of British Columbia have an equable climate and a heavy rainfall, while the lands to the east of the Rockies have an extreme climate and light rainfall. Again, the climate of the mountainous areas differs from that of the adjacent lowlands. The great mountain systems of the world are mainly important for their minerals, and, in the temperate zone, for their lumber. In the plateau regions of some mountain systems agriculture has been made possible by irrigation, and above the forests in temperate areas there are valuable alpine pastures. The swift streams of mountains are frequently sources of hydro-electric power, especially in countries which have no coal, such as Switzerland and Norway. In North America, the Western Cordillera provides gold, copper, lead, and silver, especially in the states of Nevada and Montana. The Andes provide tin and copper (Bolivia), gold and platinum
(Colombia), and silver (Peru). The Highlands of East Australia are important for copper and gold. The lumbering industry is specially important in British Columbia, Washington, and Oregon (soft woods), the Central American mountainous lands (hard woods), the Himalayan slopes (teak and sal), and the Scandinavian mountains (soft woods).

To provide food for the mining communities in inaccessible mountain areas, agriculture has been developed. There are numerous irrigation schemes in operation in most of the mountain states of the USA, e.g. at Salt Lake City in Utah. Similarly, the Andean states, e.g. Bolivia, grow small quantities of cereals in the plateau areas. Mountain pastures have been utilised most extensively for cattle rearing in Switzerland and Scandinavia. The vast central plateau of Asia is, owing to difficulty of access and climatic extremes, so isolated from other regions that very little development of any kind, on modern lines, has taken place. High mountain ranges are also barriers to communication, and so tend to separate peoples. Traffic across mountains is limited to the passes, which are often so high as to be snowbound in winter. Such ranges as the Alps, Andes, etc. can only be crossed with great difficulty or by expensive tunnelling.

It sometimes happens that movement of the earth's crust occurs along cracks or faults. Where such movement leaves a block of higher land standing between two areas of lower land, the highland is known as a 'Block Mountain' or horst. The Vosges and Black Forest Mountains are examples of such formations These mountains are usually very steep-sided, and often the summit levels are roughly the same.

When an area of highland remains standing above the general level after rivers and other natural agents have lowered the surface of the surrounding area, the name residual mountain is used. Sometimes such highlands are called 'mountains of denudation'. This term can usually be applied to the mountain ridges associated with 'dissected plateaux'. Included in this class are the mountain ridges of the Highlands of Scotland, the Sierras of Central Spain, and the Mesas and Buttes of the western plateau lands of the United States.

Mountains may be formed by volcanic material piled up around a crater, such mountains are popularly known as volcanoes.
Research Mountains

VALLEY

A valley is a long narrow depression in the earth's crust, flanked by well defined ridges and usually due to the erosive action of rivers or glaciers but sometimes due to trough-faulting.
Longitudinal valleys are the hollows between the up-folded mountain ranges, parallel to the mountains, and they usually contain a largee river. Similar valleys occur between upfoldod mountains and the crustal plateau which has resisted upheaval. The Indo-Gangetic valley between the upfolded Himalayas and the Deccan plateau is the largest example of this type.

The valley cut by vertical erosion is usually V-shaped in cross-section and irregular in its course, its gradient being punctuated by sudden drops and long shelves. These irregularities represent local base levels which are gradually removed by denudation, so that as the falls are worn back and lakes infilled the breaks in the profile are reduced. In southern England the valleys of the Severn and the Thames show the results of denudation, which has carved away the softer rocks, and left the more resistant ridges of the Cotswolds, Downs, and Chilterns, which confine the drainage system.

With lateral erosion and mass movement, the valley broadens. Deposition occurs as the gradient slackens, and floodplains fill the valley floor. Rejuvenation leaves remnants of old floodplains above the new ones in the form of terraces, the highest of which are the oldest. A lowering of the water-table may leave dry valleys, and sudden uplift may leave hanging valleys, while the flooding of valleys by the sea gives rias or 'drowned valleys' which are existing estuaries where the sea has encroached upon the lower courses of rivers, such as the Gulf of St Lawrence.
Research Valley

BOTRYCHIUM

Botrychium is a genus of ferns, one species of which (Botrychium lunaria, or moonwort) is a native of Britain, growing on elevated heaths and pastures where other ferns are seldom found. Botrychium virginicum, the largest species, is a native of North America, New Zealand, the Himalayas, etc.
Research Botrychium

CEDAR

Cedar is a tree which forms fine woods on the mountains of Syria and Asia Minor, the Pinus Cedrus of Linnaeus, the Cedrus Libdni of some other botanists, while by others it is referred to the genus Larix, and by others again, along with the larch, to the genus Abies. It is an evergreen, grows to a great size, and is remarkable for its durability. Of the famous cedars of Lebanon comparatively few now remain, and the tree does not grow in any other part of Palestine. Cedar timber was formerly much prized, but in modern times is not regarded as of much value, perhaps from the trees not being of sufficient age.

Some fine cedars are met with in England. The name is given also to the deodar (Cedar Deoddra), which is indeed regarded by many botanists as a mere variety of the cedar of Lebanon, and which produces excellent timber. It is a native of India, and is a large and handsome tree, growing in the Himalayas to the height of 45 meters, with a circumference of nine metres. It has wide-spreading branches, which droop a little at the extremities. The leaves are tufted or solitary, larger than those of the cedar of Lebanon and very numerous, of a dark-bluish green, and covered with a glaucous bloom. The cones are rather larger than those of the Lebanon cedar, and very resinous. The wood is well adapted for building purposes, being compact and very enduring.

The cedar was introduced into Great Britain in 1822, and is now common in lawns and parks. The Mount Atlas cedar (Cedar Atlantica}, as its name implies, is a native of the mountains of North Africa. This cedar, though differing in habit and minor features, is regarded by some botanists as specifically identical with the other two. The name is also applied to many trees which have no relation to the true cedar, as the Bermuda cedar (Juniperus bermudiana), used for making pencils, the red cedar (Juniperus virginiana), the Honduras, or bastard Barbadoes cedar (Cedrela odordta) and the red cedar of Australia (Cedrela australis).
Research Cedar

DECAISNEA

Decaisnea is a genus of plants of the family Lardizabalaceae found on the Himalayas. It has erect stalks which look like walking sticks and leaves 60 centimetres long. The fruit resembles a cucumber and has a sweet, yellow edible pulp.
Research Decaisnea

GOLDEN-SAXIFRAGE

Golden-saxifrage is a popular name for Chrysoplenium, a small genus of Saxifragaceae, consisting of annual or perennial rather succulent herbs, with alternate or opposite crenate leaves, and inconspicuous greenish axillary and terminal flowers. They are natives of Central and Northern Europe, the Himalayas, and parts of America. There are two British species.
Research Golden-saxifrage

IMPEY PHEASANT

The Impey Pheasant (Monaul, Lophophorus refulgens) is a bird of the pheasant family with splendid plumage found in the higher regions of the Himalayas. It is the size of a small turkey.
Research Impey Pheasant

LESSER HORSESHOE-BAT

The lesser horseshoe-bat (Rhinolophus hipposideros) greatly resembles the Greater Horsehoe-bat but is smaller, with a wing span of about 22 cm. pointed and have a well-developed antitragus very similar to that of the greater horseshoe-bat on a smaller scale, but there are small differences from that species in the details of the form of the nose-leaf. The colour is a rather greyer brown without the yellowish or pinkish shade, and the fur is proportionately longer, silkier and less velvety. The underside tends to be lighter in colour and the fur extends on to the base of the wing membranes. As in the larger species there is a bare patch at the base of the tail on the upper surface. The upper incisors, and the first upper, and the first two lower premolars are very minute. The range extends from Ireland to the Himalayas and north Africa and includes all Europe south of the Baltic. In the British Isles it is common in the south and west from Kent to Cornwall, though scarcer in Sussex and Hampshire.

The lesser horshoe-bat is found throughout Wales and the border counties but not in east Anglia or north of Yorkshire. In Ireland it is confined to the west. The lesser horseshoe-bat is gregarious, the summer colonies occurring in house and church roofs and perhaps in hollow trees. The winter colonies are nearly always in caves, but the species is not then closely gregarious, individuals usually hanging up at some distance from their neighbours. They do not always hang in the roof of the cave and often choose the undersides of projecting points or boulders where they are only a few inches from the ground. The summer colonies show a segregation of the sexes and usually consist mainly of adult females, some immature bats of both sexes, and a few adult males.

The flight is rather fluttering with frequent glides, and usually fairly near to the ground. The food consists of the smaller insects; moths appear to form a large part of the diet. The single young is born in June or July, the breeding season being rather protracted. Hibernation lasts from early October to the beginning of April, but it is frequently interrupted, the bats shifting their quarters within the hibernating cave and perhaps feeding upon the gnats which are usually found in them; but they are not known to come out into the open in the winter. Wherever caves are used by the greater horseshoe-bat for hibernation this species is found too; but because its range in Britain is much wider, it is also found in many caves outside the range of that species.
Research Lesser Horseshoe-Bat

MARKHOR

The markhor (Capra falconeri) is a large wild goat found in the Himalayas. It is readily distinguished from other species of goat by its massive, twisted horns. The markhor stands about one metre tall at the withers, and has a chin-beard often reaching to the knees. The colour varies from greyish-brown to nearly white.
Research Markhor

MOUFLON

The Mouflon or Argali is a very large mountain sheep (Ovis aries formerly Ovis musimon, Ovis ammon and others) found wild in Cyprus, Corsica, Sardinia and from Siberia to the Himalayas. It stands about 70 centimetres tall and has woolly under-fur in winter, but this is covered by heavy guard hairs. The coat is reddish brown with a white belly and rump. Males have enormous strong, curving horns reaching 120 cm in length which almost form a circle 55 cm in circumference.
Research Mouflon

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