Natural Vegetation and Wildlife Notes Class 9 Geography: Here are comprehensive chapter-notes of ‘Natural Vegetation and Wildlife’ with proper headings and suitable points to make the chapter properly understandable.
Diversity in Flora and Fauna in India
Which factors are responsible for huge diversity in flora and fauna in India?
Meaning of natural vegetation and wildlife
- Natural vegetation refers to plants that grow naturally in a region without any human aid and has been left undisturbed by humans for a long time. This is termed as virgin vegetation.
- Wildlife refers to animals, birds, and insects living in forests.
- Forests in India are the natural habitat for many plant and animal species.
India: Mega biodiversity country
- India is one of the major bio-diversity regions in the world.
- With 47,000 types of plant species, India holds the tenth position in the world and the fourth position in Asia in plant diversity.
- It also accounts for 6 percent of the world’s total flowering plant, home to 15,000 varieties.
- Many non-flowering plant species are also found in the country, such as ferns, algae, and fungi.
- India is also home to nearly 90,000 animal species and a wide variety of fresh and marine fishes.
- Virgin vegetation is the vegetation that grows naturally without any human effort.
- It remains undisturbed by any human interference for a long period of time.
- Cultivated vegetation — such as crops, fruits, orchards — does not fall under natural vegetation, as these are grown by human effort.
- Virgin vegetation found in India is known as endemic or indigenous vegetation.
- Virgin vegetation imported from outside India is known as exotic plants.
Flora and fauna
- Flora refers to plants growing in a particular region or period.
- Fauna refers to animal species living in a particular region or period of time.
- India has a huge diversity in its flora and fauna due to various factors like relief and climate.
Factors Affecting Diversity in Flora and Fauna
Variation in relief, that is, inland and soil. Variation in a climate that is, in temperature, photoperiod and precipitation.
Relief — Land
- The type of vegetation found in mountains, plateaus, and plains is different from one another.
- Vegetation also varies between dry and wet regions of the country.
- The topography of land influences the type of vegetation growing in a region.
- On undulating lands, vegetation grows in the forms of grasslands and woodlands. Such vegetation provides shelter to a variety of wildlife species.
- Fertile lands are used for growing crops.
Relief — Soil
- Types of soil vary from one place to another.
- There are broadly six varieties of soil found in India — alluvial soil, desert soil, black soil, red and yellow soil, laterite soil, and forest soil.
- The type of vegetation that grows in an area depends on the type of soil found there. For example, mountain soil supports the growth of conical trees such as pine, fir, and oak, whereas only plants like cactus with thick leaves and stems can thrive in desert soil.
- Mangroves thrive in the sticky soils of the river deltas.
Climate — Temperature
- Temperature, along with the humidity in the air and precipitation, determines the type of vegetation growing in an area.
- The temperature is highest at sea level and lowest at the peak of mountains. Temperature decreases gradually as altitude increases.
- Variation in height, along with the fall in temperature, determines the type of vegetation and its growth at various altitudes.
- For this reason, vegetation is dense and thicker at the foothills, while only a few types of bushes can thrive on the snowy peaks of the mountains.
- Based on the temperature, vegetation may change from tropical to subtropical and from temperate to alpine vegetation.
Climate — Photoperiod or sunlight
- The earth is spherical in shape, so that the amount of sunlight received varies from one place to another.
- Regions close to the equator have a high temperature as they receive direct rays of the sun.
- Regions near the poles have low temperatures as they receive slanting rays of the sun.
- The period of sunlight at a place depends on:
- Season and
- Duration of the day.
- Trees grow faster in the summer season as they receive more sunlight.
Climate — Precipitation
- India receives most of its annual rainfall in two monsoon seasons — southwest monsoon season (June to September) and retreating monsoon season or northeast monsoon season (October to December).
- The natural vegetation is thicker in areas that receive high rainfall than in areas receiving low rainfall.
- For example, the vegetation is denser in the north Gangetic plains than in the dry areas of Rajasthan.
Importance of forests
Forests are an important renewable natural resource. Forests are useful for human beings in the following ways:
- They regulate the local climate.
- They prevent soil erosion.
- They regulate the speed of flowing water.
- Forests support a variety of industries such as the paper industry, wood construction industry.
- They provide a source of livelihood for many communities.
- Forest safaris are good recreational activities.
- Trees in forests work as barriers to wind flow and check the speed of the wind.
- Forest cover also helps to regulate temperature and cause rains.
- Forest soil is rich in humus content, which is good for plant growth.
- It is the natural habitat of many wild animal and bird species such as tiger, lion, elephant, hornbill, umbrella bird.
Forests in India
- According to the Union Ministry for Environment, Forest and Climate Change, 24.56 percent of the total geographical area of the country is under forest cover.
- Over the years, the natural vegetation in India has undergone many changes.
- These changes are mainly due to the growing demands of the increasing population.
- Demand for more cultivable land to meet the food need of the population
- Establishment and development of industries
- Excessive mining activities
- Overgrazing of pasture lands
Are forests in India natural forests?
- Only the very remote and inaccessible forest regions of the Himalayas, Central India, and Marusthali in the western part of Rajasthan can be recognised as the natural forest cover of India.
- Most other forests in the country have been altered, modified, replaced, or degraded by human activities.
Types of Vegetation Found in India
Based on the type of soil and climatic conditions, the forests of India can be broadly classified into:
- Tropical evergreen forests
- Tropical deciduous forests
- Tropical thorn forests and scrubs
- Montane forests
- Mangrove forests
Tropical evergreen forests
- These forests are found in areas that receive rainfall of more than 200 cm in a year and experience a short dry season.
- The forests are found in areas with heavy rainfall, such as:
- Western Ghats
- Island groups of Lakshadweep, Andaman, and Nicobar
- Upperparts of Assam
- Tamil Nadu coast
- Due to the warm and wet climate, the forests have a dense growth of trees, shrubs, and creepers that grow in layers.
- The multi-layered structure of trees in such forests is known as the canopy.
- Tropical evergreen forests appear green throughout the year as the trees shed their leaves at different times of the year.
- Ebony, mahogany, rosewood, rubber, and cinchona are a few trees that grow in these forests.
- Elephants, monkeys, lemurs, deer, and one-horned rhinoceroses live in these forests.
- Many birds besides bats, sloths, scorpions, and snails are also found in these forests.
Tropical deciduous forests
- Tropical deciduous forests are the most common types of forests found in India.
- These forests are also known as monsoon forests as the leaves of the trees regrow during the monsoon.
- These forests are found in regions where annual rainfall is between 70 cm to 200 cm.
- Trees in these forests shed their leaves during six to eight weeks in the summer. The leaves regrow in the monsoon.
- On the basis of the availability of water, these forests are classified into wet and dry forests.
Tropical deciduous moist forests
- These forests grow in the regions that get rainfall between 100 to 200 cm.
- These forests are found in the eastern part of the country, northeastern states, along the foothills of the Himalayas, Jharkhand, West Odisha, and Chhattisgarh, and on the eastern slopes of the Western Ghats.
- Teak grows abundantly in these forests.
- Other trees found here are bamboo, sal, shisham, sandalwood, Khair, Kusum, Arjun, and mulberry.
Tropical deciduous dry forests
- Tropical deciduous dry forests are confined to areas that receive rainfall between 70 to 100cm.
- These forests are found in the parts of the peninsular plateau, Bihar, and Uttar Pradesh plains that receive adequate rainfall.
- These forests are characterised by open stretches. Teak, sal, peepal, and neem grow in these stretches.
- The trees shed their leaves in the dry season.
- Local people clear the forests for cultivation and grazing activities.
- These forests are habitats for lions, tigers, pigs, deer, elephants, and various birds, lizards, snakes, and tortoises.
Thorn forests and scrubs
- Semi-arid and arid regions of the country witness growth of such forests.
- These forests are found in the north-western parts of the country with deficient rainfall below 70 cm.
- Thorn forests and scrubs are found in Gujarat, Rajasthan, Madhya Pradesh, Chhattisgarh, Uttar Pradesh, and Haryana.
- Only plants with long roots, thick stems, and leaves can survive the harsh climate of these regions.
- The long roots help the plants to reach and take underground water.
- The thick stems and leaves help to reduce the loss of water through evaporation and so conserve water.
- Rats, mice, rabbits, foxes, wolves, tigers, lions, wild ass, horses, and camels are the animals found in these forests.
- Dates grow in the damper regions of these forests.
Montane and Mangrove Forests
- The type of natural vegetation in mountains changes as temperature decreases with the rise in altitude.
- From tropical to tundra regions, there is a succession of natural vegetation belts.
Montane forests between 1,000–2,000 metres
- Between altitudes 1,000 and 2,000 metres, wet temperate forests are found.
- Trees in these forests are characterised by broad green leaves.
- Oak and chestnut are commonly found in these altitudes.
Montane forests between 1,500–3,000 metres
- Temperate forests are found between these altitudes.
- Trees like pine, deodar, silver fir, spruce, and cedar are found between 1,500 and 3,000 metres.
- This type of vegetation is common on the southern slopes of the Himalayas and at higher altitudes in southern and north-eastern India.
Montane forests above 3,600 metres
- Beyond 3,600 metres, alpine vegetation is common.
- Such vegetation comprises temperate forests and grasslands.
- Silver fir, junipers, pines, and birches are the common trees of these forests.
- The growth of trees gradually diminishes towards the snowline.
- Shrubs and scrubs in this region are used mainly for grazing.
- Nomadic tribes named Gujjars and Bakarwals use this vegetation for grazing their cattle.
- At much higher altitudes, mosses and lichens form part of tundra vegetation.
Wildlife in montane forests
The animals found in montane forests are: – Kashmir stags, Spotted deer, Wild sheep, Jackrabbits, Tibetan antelopes, Yaks, Snow leopards, Squirrels, Shaggy horn wild ibex, Rare red pandas, Thick-haired bears, Sheep, and, Goats
- Mangrove forests are found in coastal areas that are influenced by tides.
- Due to high and low tides occurring twice a day, mud and silt accumulate on the coasts.
- Trees in mangrove forests thrive in such soil.
- Roots of trees in mangrove forests remain submerged underwater.
- Mangroves are common on the deltas of the river Ganga, Mahanadi, Krishna, Godavari, and Kavery.
- The Sundari tree is found in the Ganga-Brahmaputra delta.
- Sundari tree provides durable hard timber that is used to make many products.
- Other trees that grow in these deltas are palm, coconut, keora, agar, etc.
Wildlife in mangrove forests
- Mangrove forests are home to the Royal Bengal tiger.
- Other animals found in these forests are turtles, crocodiles, gharials, and snakes.
How is India’s fauna diverse?
Wildlife in India
- Like flora, India has rich fauna.
- There are 90,000 species of animals and 2,000 species of birds in the country.
- Together they constitute 13 percent of the world’s total wildlife.
- With 2,546 species of fish, India accounts for 12 percent of the world’s fisheries stock.
- The country also accounts for 5 to 8 percent of the world’s amphibians, reptiles, and mammals.
Distribution of wildlife species in India
- The majestic mammal, the elephant, is found in the hot and wet forests of Assam, Karnataka, and Kerala.
- The swampy and marshy lands of Assam and West Bengal are home to the one-horned rhinoceros.
- Wild asses and camels live in the arid regions of the Rann of Kachchh and the Thar Desert.
- Indian bison, nilgai (blue bull), chousingha (four-horned antelope), gazelle, and various deer and monkeys are also found in India.
Unique wildlife species of India
- India is the only country in the world where we find both tigers and lions.
- Tigers live in the forests of Madhya Pradesh, the Sundarbans of West Bengal, and the Himalayan region.
- The Gir forest of Gujarat is home to lions.
- Leopards are also found in the country.
- Lions, tigers, and leopards belong to the cat family and are predators.
Wildlife in the Himalayas
- The Himalayas are home to many wild animals.
- The freezing temperature of the Himalayas and Ladakh is the natural habitat of yak, the shaggy horned wild ox, the Tibetan antelope, the bharal (blue sheep), wild sheep, and the kiang (Tibetan wild ass).
- The ibex, bear, snow leopard, and rare red panda are also found in some parts of the Himalayas.
Wildlife in coastal areas
- Coastal areas are home to turtles, crocodiles, and gharials.
- Gharial also belongs to the crocodile family and is the longest of all living crocodiles.
Birds in India
- India has a great variety of birds.
- Peacocks, pheasants, ducks, parakeets, cranes, and pigeons are some of the birds living in the wetlands of the country.
Uses of wildlife to humans
- Various plants are used for making medicines.
- Some wild animals also provide draught power, transportation, meat, and eggs.
- Fish are an important part of meals in many parts of India.
- Fish add to the nutritive value of the diet.
- Insects such as honey bees help in the pollination of flowers and crops.
- Each wildlife species on earth has an important role to play and is useful to human beings either directly or indirectly.
Conservation of wildlife
- Human activities have exploited plant and animal species on the planet.
- To meet their demands, human beings have disturbed the various ecosystems in the natural environment.
- Around 1,300 plant species are endangered, and 20 species are already extinct.
- Many wild animals, such as tigers and rhinoceroses, have also been categorised as endangered in the country.
- Certain wildlife species, such as pink-headed duck and cheetah, are extinct.
Effects of human activities on wild species
- Human activities have led to the deterioration of the condition of wildlife in India.
- Human activities that have led to a decline in the number of wildlife species are:
- Hunting of animals
- Pollution of water bodies by industrial waste affects many aquatic and terrestrial wildlife species
- Acid deposits on the land and in water that is lethal for animals
- Hybrid varieties of plants and animals generated through human experiments also have adverse effects on the environment.
- Deforestation due to the expansion of agricultural activities and urbanisation has severely affected many wildlife species.
- Human activities have caused imbalances in the natural environment that have, in turn, affected many food chains and food webs.
Conservation and Protection of Flora and Fauna
Status of wildlife in India
- The fast-degrading conditions of India’s forests and the rate at which deforestation is taking place have adversely affected the wildlife of the country.
- This has caused various species to be endangered or go extinct or approach these conditions. Such decline in the population of wildlife has disturbed the ecological balance.
- There is an urgent need to conserve the wildlife species in the country.
Steps were taken by the government for conservation
- To protect the wildlife in the country, the government has taken four major steps:
- Set up biosphere reserves.
- Provide financial aids to botanical gardens.
- Launch special projects to save endangered species such as Project Elephant, Project Rhino.
- Set up national parks, wildlife sanctuaries, and zoological gardens to save the natural habitats of wild animals.
Biosphere reserves in India
- There are 18 biosphere reserves in India.
- Biosphere reserves are set up to conserve the rich flora and fauna of the country.
- Out of 18, 10 biosphere reserves are part of a world network.
- These are-the Sundarbans, Nanda Devi, the Gulf of Mannar, the Nilgiri, Nokrek, Great Nicobar, Manas, Simlipal, Pachmarhi and Achanakmar-Amarkantak
- Other biosphere reserves are- Dihang-Dibang, Dibru Saikhowa, Agasthyamalai, Kangchendzonga
Migratory birds in India
- Different migratory birds fly to India during the winter months, such as Siberian cranes and flamingos.
- These birds spend their stay in India near the wetlands. For example, Chilika lake in Odisha, Rann of Kachchh, parts of peninsular plateau.
- Flamingos prefer parts of the Rann of Kachchh where the sea meets the desert.
- Flamingos migrate to India to raise their young. They built nests using the salty muds of the Rann of Kachchh.
- The migration of these birds to different parts of the country is a tourist attraction.
- The government has been providing financial and technical supports to four botanical gardens in the country since 1992.
- The four botanical gardens in the country are:
- Cold Desert
- Sesha Chalam, and
Projects by the government
The government has launched various projects from time to time to conserve various endangered species in the country.
- Project Tiger
- Project Rhino
- Project Elephant
- Project Gharial
National parks and wildlife sanctuaries
- The government has set up 103 national parks and 535 wildlife sanctuaries in India.
- These have been set up to take care of the natural heritage of the country.
- Some of the national parks and wildlife sanctuaries are- Ranthambore, Gir, Manas national parks, Sariska, Mahanadi, Kawal wildlife sanctuaries.
- Some bird sanctuaries are also set up in the country, such as Ranganathittu and Vedanthangal.
- Certain laws were made and enforced in India to protect wildlife. For example, the Wildlife Protection Act of 1972 prohibits trade in endangered and rare wildlife species in the country.