The northern part of India falls in the sub tropical and temperate zone and the southern part lies in the tropical zone. The southern region has smaller annual and diurnal temperature range but the northern region has higher range.
People living on the coast have an equable temperature throughout the year due to moderation by sea but people living in the interiors experience extreme weather.
In places that are colder, the air becomes heavy. The cold heavy air sinks and creates a high pressure. High pressure area is associated with a clear sunny sky.
Fig 2: Vegetation map of India
Tropical forest is well stratified. Layers closer to the ground are covered with shrubs and creepers, followed by short structured trees and tall structured trees.
This is of two types southern Montane and northern montane forests.
Mangroves in the eastern region of India are more luxuriant and diverse due to the presence of nutrient rich deltas of the rivers.
The east and northeast margins of continents are covered by temperate evergreen and temperate deciduous trees. The west and southwest margins of continents are covered with Mediterranean vegetation.
Fig 3: Altitude wise vegetation stratification
In Himachal Pradesh and Arunachal Pradesh, Himalayan yew trees are found that are used to obtain Taxol – a chemical that cures cancers. Quinine – to cure malaria is from cinchona tree, drug for leukemia from vinca rosea. Aspirin – tropical willow tree.
In mountainous regions, the decreasing temperature with increasing altitude leads to corresponding change in the natural vegetation. In this ranges all types of vegetation occur from tropical to tundra. Wet temperate forests are seen between 1000 – 2000 m. between 1500 – 3000 m coniferous forests of temperate types are seen. Above 3600m alpine grasslands are seen. Himalayan ranges are an example of this.
Tropical regions occupy one fourth of the total area of the world but have 75% of the total world population.
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Q1:Southern India has lower temperature variation due to
3.closer to sea
4.far from mountains
Q2:Taxol is obtained from
Q3:Altitude wise vegetation means at height of 3000m and above which vegetation is seen
4.mosses and lichens
Q4:Advantages of mangroves are
1.protect coastal regions from cyclones
2.are a source of wood for housing
Q5:High pressure area is associated with