Social Science 2 Marks Each

Tropical forests are found almost all part of the India and are called evergreen forests because:

1. Tropical rain forests are found in hot and humid regions where annual rainfall exceeds 200 cm.
2. Trees of these forests do not shed their leaves fully in any season.
3. Hence, they remain green throughout the year and are known as evergreen forests.
4. In other words, since the trees do not shed their leaves fully in any season these forests do not see autumn season.

Effects of destruction of forests: Destruction of forests causes several adverse and harmful effects.
Decreased rainfall, drought, global warming, greenhouse effect, advancing deserts, lost habitat of wild animals, etc, are some of these effects.

Forests provide countless things as raw material or even readymade products.
The products obtained through forests hold good commercial value all over the world.
The rare and useful flowering plants, herbal plants, etc. are used in many medicines and cosmetics and hence earn a very good revenue.

Trees inhale harmful carbon dioxide and exhale oxygen and hence purify the atmosphere.
Temperature remains low and environment becomes pleasant due to trees.
Moreover, trees reduce air pollution, bring rains, check soil erosion, etc.
Due to all these reasons, it can be said that forests play an important role in maintaining environmental balance.

Coniferous forests are found in high altitudes of Himalayas between 1000 metres and 3600 metres and above.
Such high regions often experience snowfall.
The leaves are of distinct conical shaped with branches leaning downwards.
This type of leaves helps the trees to easily slide down the snow that fall on them.
Hence, leaves of coniferous forests are quite different than usual trees.

In deciduous forests, trees shed their leaves on specific time. All the trees do not shed leaves together.
The trees shed leaves for only 6 to 8 weeks during autumn.
Since these trees shed their leaves according to seasons, these are also called monsoon forests.

Plants such as white Khakhro, gugal, nilsoti, sesame, amli, attak, harde, etc. are enlisted in Red Date Book of I.U.C.N. (International Union for Conservation of Nature). The reason for this is that these plants fall in the category of ‘on verge of extinction’.

According to the National Policy of 1952, about 33% of the total geographical area of India should be covered with forests. However, our forests are covered only in 23%. Gujarat is far behind in this number with just 10% of its area under forests.

The various kinds of flora i.e.. plants that grow naturally in a region is known as natural vegetation of that region. For example, in Gujarat we find neem (limda), baaval, etc. grown everywhere.
India has diverse natural vegetation. With respect to diversity in vegetation, India stands 10th rank in the world and 4th rank in Asia.
A large area which is mainly covered with trees and plants in called a forest.

• Forests provide timber, fuel wood and various other things.
• Various industries have developed such as paper-making, rayon, basket, small baskets, toys, mats and handicrafts items turpentine from the fluid of chid tree, sports goods, matchsticks, packing boxes for tea and medicines from pine and chid trees, fragrant sandalwood oil and other cosmetics from sandal- wood trees, leaf plates and bowls from khakhro leaves, catechu from kher trees and _ bidi from timru leaves.
• Many herbal medicines like harde, baheda, ashwagandha, amla, cinchona, sarpagandha,
• nilgiri, eucalyptus, etc. are obtained from forests.
• Products like lac, resin, gum, cane, honey, ‘rubber, etc. are obtained from forests.
• Forest provide employment to forest-dwellers. So forests are useful in the national development.

• Tropical Desert Vegetation :
• (i) Distribution : These forests are found in the regions receiving less than 70 cm rain.
• These forests are found in Gujarat, Rajasthan, Madhya Pradesh, Uttar Pradesh, Haryana and some rain shadow area of Western Ghats.
• (ii) Trees: Date, jujube, acacia, cactus, khijdo, etc.
• (iii) Characteristics: The roots of these trees are long, deep and are spread like radius of a circle to procure water.
• Their leaves are shorter so the process of transpiration is slower.
• Trees in these forests are scattered.

• Characteristics : Here, the trees shed their leaves completely for 6 to 8 weeks during autumn. So these are called ‘Deciduous Forests.
• The specific time to shed their leaves is different among the trees of all species. So the entire‘ forest is never barren.
• As the trees shed their leaves according to the season, these are also called ‘Monsoon Forests’.

• Characteristics :
• (1) Here the trees are 60 metres tall or even higher.
• (2) There is more humidity due to scrubs.
• (3) There is no autumn season in these forests.
• (4) As the trees are evergreen, these are also called ‘Evergreen Forests’.
• (5) The girth of the trees is very thick and the wood is also very hard and heavy.