Chapter 6 - Natural Vegetation and Wildlife Notes
1. Natural vegetation is generally classified in to three broad categories as follows:
a) Forests: Which grow where temperature and rainfall are plentiful to support a tree cover. Depending upon these factors, dense and open forests are grown.
b) Grasslands: Which grow in the region of moderate rain.
c) Shrubs: Thorny shrurbs and scrubs grow in the dry region
2. The changes in the type of natural vegetation occur mainly because of the changes of climatic condition.
3. There are 6 types of forest. They are:
a) Tropical Evergreen Forests
b) Tropical Deciduous Forests
c) Temperate Evergreen Forests
d) Temperate Deciduous Forests
e) Coniferous Forests
f) Mediterranean Vegetation
4. Tropical Evergreen Forest are also known as Tropical Rainforest. They occur in the regions near to the equator and close to the tropics. They receive very heavy rainfall and hot. The trees in these forests don't shed their leaves altogether. The thick canopies don't allow the sunlight to penetrate. Rosewood, Ebony, Mahogany are found.
5. Tropical Deciduous forests are also known as Monsoon forests. They are found in large parts of India, Northern Australia, and Central America. These regions experience seasonal changes. Trees shed their leaves in dry season to conserve water. Hardwood trees found here are sal, teak, neem, shisham. These trees are useful for making furniture, transport and constructional materials. Tigers, lions, elephants, langoors and monkeys are common here.
6. Temperate Evergreen forests are located in the mid-latitudinal coastal regions. They are found in the eastern margins of the continents. Eg in South-east USA, South China and in South-east Brazil. They have both hardwood and softwood trees like oak, pine, eucalyptus.
7. Temperate Deciduous forests are found in higher latitudes. They are found in the north east part of USA, China, New Zealand, Chile and in coastal regions of western Europe. The trees in these forests shed their leaves in dry season. The common trees here are oak, ash, beech etc. Animals found here are deer, fox, wolves, pheasants, monal etc.
8. Coniferous forests are found in higher lattitudes (50 degrees - 70 degrees) of Northern Hemisphere. These forests are also called Taiga which means pure or untouched in Russian language. Trees are tall, softwood which is useful in making paper, match box and packing box etc. Chir, Pine, Cedar are the trees found here. Animals like silver fox, mink, polar bear are found.
9. The west and southwest margins of the continents have Mediterranean Vegetation. It is mostly found in the areas around the Mediterranean sea in Europe, Asia and Africa. This vegetation is also found in California in USA, Southwest Africa, Southwestern South America and Southwest Australia. This region is marked for hot dry summers and mild rainy seasons. Citrus fruits such as figs, orange are cultivated.
10. There are 2 types of Grassland
a) Tropical Grassland
b) Temperate Grassland
11. Tropical Grasslands occur on the either sides of the equator and extend till the tropics. This vegetation grows in the areas of moderate to low amount of rainfall. The grass can grow up very tall, about 3 - 4 metres high. Savannah grasslands of Africa are of this type. Elephants, zebras, giraffes, deer, leopards are common in tropical grasslands.
12. Temperate Grassland are found in the mid-morning latitudinal zones and in the interior parts of the continents. The grass here are short and nutritious. Wild buffalos, bisons, antilopes are common in Temperate grasslands.
13. Thorny bushes are found in the dry desert like regions. Tropical deserts are located on the western margins of the continents. The vegetation cover is scarce here because of scanty rain and scorching heat.
14. Tundra vegetation is found in the polar areas of Europe, Asia and North America. The animals have thick fur and thick skin to protect themselves from the cold climatic conditions. Seal, walruses, musk-oxen, Arctic owl, Polar bear and snow foxes are some of the animals found here. Only mosses, lichens and very small shrubs are found here. It grows during the very short summer.
15. The tropical evergreen forest in Brazil is so enormous that it is like the lungs of the Earth.
16. Anaconda, one of the world’s largest snakes is found in the tropical rainforest. It can kill and eat a large animal such as a crocodile.
17. Mediterranean trees adapt themselves to dry summers with the help of their thick barks and wax coated leaves which help them reduce transpiration.
18. Mediterranean regions are known as ‘Orchards of the world’ for their fruit cultivation.
19. Taiga means pure or untouched in the Russian language.
20. Grasslands are known by different names in different regions.
Tropical Grasslands
a) East Africa - Savanna
b) Brazil - Campos
c) Venezuela - Llanos
Temperate Grasslands
Argentina - Pampas
North America - Prairie
South Africa - Veld
Central Asia - Steppe
Australia - Down
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