The Subtropics. Forests of the Torrid Zone. Savannahs
The Subtropical Regions. The coastal belts of Asia Minor facing the seas have a Mediterranean climate and a subtropical vegetation similar to that of Southern Europe: evergreen shrubs and trees such as myrtle, oleander, laurel and evergreen oak.
Fig. 96. The Indian jungles. People riding tame elephants
On the Black Sea coast of the Caucasus, where the climate is wet and rains fall at all seasons, the vegetation is that of the wet subtropical type. There grow thick forests of maple, beech, chestnut and walnut. Among these occur evergreen trees and bushes: laurel, cherry-laurel and box with wood as hard as bone. Ivy, vines and other climbers twine round the trunks of the trees. Tea, tangerines, oranges and lemons are grown here. In the most beautiful places there are resorts at the service of the working masses of the Soviet Union.
Still more varied is plant life in the wet subtropical regions in the south of the Great China Plain (the Yangtze basin), in the bordering mountains and in South Japan. Side by side with evergreen oak and laurel, grow camphor, varnish, bamboo, magnolia with large, white flowers, camellia and sometimes palm.
Natural vegetation is rarely met, however. Nature has been greatly changed by man in these densely populated regions. The soil almost everywhere is under rice and cotton. The tea-plant of South-Eastern Asia and the mulberry tree are widely cultivated.
Of great economic importance is bamboo, prized for its stems. Though Ifght it is very strong and is used for building purposes, furniture and water-pipes.
Equatorial and Tropical Forests 'and Savannahs. The peninsulas of Hindustan and Indo-China and the Sunda Islands are covered with the rich vegetation of the torrid zone. The high, uniform temperatures arid the heavy rainfall favour plant growth. Rainfall is not everywhere the same, however. In regions with especially heavy rainfall (over 1,000 mm a year) grow equatorial and tropical rain forests. These cover the Sunda and Philippine Islands, parts of Ceylon, Hindustan and Indo-China. The southern slopes of the Himalayas are covered with a dense, tangled, often almost impenetrable tropical undergrowth called jungle (Fig. 96).
An equatorial forest and tropical rain forest is a thickly wooded area of various evergreen trees. Rarely do two trees of the same kind grow side by side. There grow various kinds of palm, tree-ferns, bamboo and bread-trees. Very widespread are spice-bearing plants, such as clove, pepper, cinnamon. The wood of many trees (iron-wood, ebony, mahogany) is used in making furniture.
Fig. 97. An equatorial forest on the Greater Sunda Islands. In the centre is a tree-fern.
These forests grow in tiers. There are trees that reach a height of from 60 to 80 metres, with trunks like pillars and crowns of branches and leaves at the very top. Beneath these giants grow
several tiers of lower trees. It is dark in the forest. The sun's rays hardly penetrate through the thick foliage.
The density is increased by a great number of lianas — rope-like climbers that entwine the trunks and spread from tree to tree making an impassable tangle (see the coloured picture of an equatorial forest). On the trunks, branches and leaves of the trees grow small plants. Some of these have no green leaves of their own and live on the sap of the trees. Such plants are called parasites.
Especially luxuriant and varied are the equatorial forests of the Greater Sunda Islands (Fig. 97).
Tropical forest vegetation is much poorer on the coasts of Indo-China and Hindustan, where monsoon winds blow. Many of the local trees drop their leaves during the dry season.
There are no tropical rain forests in regions with a lower rainfall, such as the Deccan Plateau and the valleys of Indo-China, which are sheltered from the ocean winds by mountains. These regions consist of savannahs, or tropical grasslands, that are covered with tall, tough grass among which, singly or in clusters, grow small trees—acacia and mimosa.
On the mountain slopes the vegetation changes with the altitude. The southern slopes of the Himalayas are covered with tropical jungles to an altitude of 1,000 metres above sea level. These are followed by subtropical forests, which give way to the deciduous and coniferous forests of the temperate zone. Next come thickets of undersized trees, bushes and Alpine pastures. And finally, the eternal snow region, a kingdom of snow and glaciers.
There are many animals in the forests and savannahs of Southern Asia. The trees are the homes of various kinds of monkeys. On the Greater Sunda Islands live large anthropoid apes — orang-outangs and gibbons. On the edges of the forests there is elephant, the largest of living animals. Of the flesh-eating animals there is tiger and leopard. There is rhinoceros, buffalo (a kind of wild ox), deer and wild-boar. There are many lizards and snakes: the boa, for example, up to 7 metres in length, and the cobra whose bite is lethal.
Nature has been greatly changed by man in Southern Asia. Southern Asia is densely populated, and large areas that were formerly covered with forests and savannahs are now under cultivation. The crops include rice, tea, cotton and sugar-cane. As the weather is warm all the year round, several crops a year are gathered in from one and the same field. The cinchona tree is widely cultivated. From its bark a medicine is obtained, which is used to cure malaria. The coco-palm grown here is prized for its nuts, which are used in making oil. Of great importance are the rubber-bearing plants (rubber is made of caoutchouc, which is the hardened sap of the rubber plant).
Questions and Assignments.
- Trace on the outline map the boundaries of the subtropical
regions, the forests of the torrid zone and the savannahs.
- Study the map of Asia and name the zones that follow each
other from north to south along longitude 80° E.
- Use all your maps to describe the natural features of Java
(one of the Greater Sunda Islands).
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