NCERT Summary: India - Climate Vegetation & Wildlife - Social Studies (SST) Class 6

Weather

• The day to day changes in atmosphere is called weather. 
• Weather includes changes in temperature, sunshine and rainfall.

Seasons in India

There are four major seasons in India, viz. cold season, hot season, southwest monsoon and retreating monsoon.

• Cold Weather Season or Winter Season: The winter season continues from December to February in India. During this season, the sun rays do not fall directly on India.
• Hot Weather Season or Summer Season: The summer season continues from March to May in India. During this season, the sun rays fall more or less directly on India. Due to this, the temperature remains high during this period.
• Southwest Monsoon Season or Rainy Season: The rainy season falls from June to September. The onset and advancement of monsoon takes place in this season.
• Season of Retreating Monsoon or Autumn: This season falls in October and November. During this season, the monsoon winds move from the mainland to Bay of Bengal and hence it is called the retreating monsoon.

Climate

• Overall pattern of weather at a place is called climate. 
• For this, weather pattern of at least 20 years is taken into consideration. 
• The climate of India is called monsoon climate. 
• This is hot and humid in most parts of the country.

Natural Vegetation

• Plants which grow on their own without human intervention are called natural vegetation. 
• It depends on various climatic conditions and especially on rainfall.
• There are five types of natural vegetation in India.
  (i) Tropical Rain Forest: Tropical rainforest is found in those areas which receive heavy rainfall. The tropical rainforest is so dense that sunlight does not reach the ground. The trees of the tropical rainforest shed their leaves at different times of the year.
  (ii) Tropical Deciduous Forest: These are also called monsoon forests. The trees of deciduous forest shed their leaves at a particular time of the year. Hence, such a forest is called deciduous forest.
  (iii) Thorny Bushes: This type of vegetation is found in dry areas. The leaves are in the form of spines. This helps the plant to reduce loss of water.
  (iv) Mountain Vegetation: Different types of species are found in the mountains at different altitudes. At the height between 1500 meter and 2500 meter, most of the trees are conical in shape. Due to this, they are called coniferous trees.
  (v) Mangrove Forest: Mangrove plants can survive in saline water. They are mainly found in the Sunderbans in West Bengal and in the Andaman and Nicobar Islands. Sundari is a well known tree in the mangrove forest of Sunderban.

Importance of Forest

• Plants absorb carbon dioxide and release oxygen. Oxygen is utilized by us for breathing.
• Roots of plants bind the soil. Thus, plants prevent soil erosion.
• Forests provide us timber for furniture and firewood. They also provide fodder, medicinal plants and herbs. We also get lac, honey and gum from forests.
• Forests are the natural habitat of wildlife.

Loss of Natural Vegetation

• Humans have destroyed a large tract of forest by recklessly cutting trees for various purposes. 
• Forests are cleared for making way for agriculture and for making townships and factories. This is creating environmental problems for us. 
• Van Mahotsav is being organized to educate people about the importance of forests.

Wildlife

• Animals which live in natural vegetation are called wild animals. Thousands of animal species live in forests.
• Tiger is the national animal of India. It is found in various parts of our country.
• The Asiatic lions live in the Gir forest in Gujarat.
• Elephants are found in Kerala, Karnataka and Assam. Assam is also the home for one-horned rhino.
• Wild goats, snow leopards, bears, etc. are found in the Himalayan region.
• Peacock is out national bird.
• Parrots, pigeons, mynah, geese, bulbul and ducks are the other common birds.
• Due to large scale cutting of forests, natural habitat of many wild animals has become less. Many animals are in danger of becoming extinct. Many animals have already become extinct.
• Extinct Species: A species which no longer exists is called and extinct species.
• Endangered Species: A species which is in danger of becoming extinct is called endangered species.