There is a close relationship between the height of land and the character of the vegetation. With the change in height, the climate changes and that changes natural vegetation. The growth of vegetation depends on various factors such as temperature, moisture, slope, and thickness of soil.

Natural vegetation is generally classified into three broad categories:

1. Forests: Which grow where temperature and rainfall are plentiful to support a tree cover. Depending upon these factors, dense and open forests are grown.
2. Grasslands: Which grow in the region of moderate rain.
3. Shrubs: Thorny shrubs and scrubs grow in the dry region.

Forests

1. Tropical Evergreen Forests:

   1. These forests are also called tropical rainforests. These thick forests occur near the Equator and close to the tropics.
   2. These regions are hot and receive heavy rainfall throughout the year.
   3. As there is no particular dry season, the trees do not shed their leaves altogether. This is the reason they are called evergreen.
   4. The thick canopies of the closely spaced trees do not allow the sunlight to penetrate inside the forest even in the daytime. Hardwood trees like rosewood, ebony, and mahogany are common here.

2. Tropical Deciduous Forests:

    

   1. These are monsoon forests that are found in large parts of India and also in northern Australia and Central America.
   2. These regions experience seasonal changes. Trees shed their leaves in the dry season to conserve water.
   3. The hardwood trees found in these forests are sal, teak, neem, and shisham. Hardwood trees are extremely useful for making furniture, transport, and constructional materials.

3. Temperate Evergreen Forests:

   1. These forests are located in the mid-latitudinal coastal region.
   2. They are commonly found in the eastern margin of the continent, e.g., in southeast USA, South China, and southeast Brazil.
   3. They comprise both hard and softwood trees like oak, pine, eucalyptus, etc.

4. Temperate Deciduous Forests:

   1. These forests are located in higher latitudes.
   2. Found in the north-eastern part of the USA, China, New Zealand, Chile, and also found in the coastal regions of Western Europe.
   3. They shed their leaves in the dry season. The common trees are oak, ash, beech, etc.

5. Mediterranean Vegetation:

   1. The west and south-west margins of the continents have Mediterranean vegetation.
   2. It is mostly found in the areas around the Mediterranean Sea in Europe, Africa, and Asia.
   3. Also found outside the actual Mediterranean region in California in the USA, South-West Africa, south-western South America, and Southwest Australia.
   4. These regions are marked for hot dry summers and mild rainy winters. Citrus fruits such as oranges, figs, olives, and grapes are commonly cultivated here.

6. Coniferous Forests:

7. These forests are found in the higher latitudes (50°-70°) of the Northern hemisphere. These forests are also seen in the higher altitudes.
8. These are also called Taiga forests.
9. They are tall, softwood evergreen trees. Woods of these trees are very useful for making pulp, which is used for manufacturing paper and newsprint.
10. Chir, pine, cedar, etc. is the important variety of trees in these forests.

Grasslands:

1. Tropical grasslands: These occur on either side of the Equator and extend to the tropics. This vegetation grows in areas of moderate to low amounts of rainfall. The grass can grow very tall, about 3 to 4 metres in height. Savannah grasslands of Africa are of this type.
2. Temperate grasslands: These are found in the mid latitudinal zones and the interior part of the continents. Usually, the grass here is short and nutritious.
3. Thorny bushes: These 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.

 Tundra type of vegetation:

1. The growth of natural vegetation is very limited.
2. Only mosses, lichens, and very small shrubs are found here. It grows during the very short summer.
3. This vegetation is found in the polar areas of Europe, Asia, and North America.
4. The animals have thick fur and thick skin to protect themselves from the cold climatic conditions.
5. Seal, walruses, musk-oxen, Arctic owl, Polar bear, and snow foxes are some of the animals found here.