IX Geography Ch-5 Natural Vegetation and Wild Life

 

IX   Geography Ch-5

Natural Vegetation and Wild Life

 

Natural vegetation : Meaning and its Importance

Natural Vegetation

 

*Natural Vegetation refers to a plant community which has grown naturally without human aid and has been left undisturbed by humans for a long time.

*This is also known as Virgin Vegetation.

 

*Cultivated crops and fruits, orchards form part of vegetation but not natural vegetation.

 

*India's natural vegetation has undergone drastic changes. Still, it holds key position in areas of inaccessible hilly regions and deserts.

*Only about 23 per cent of the land area of India is at present under forests. It is far lower than the desired 33 per cent outlined in the National Forest Policy.

 

 

Flora & Fauna

 

*Flora: Plant species of a particular region or period are called flora.

*Fauna: The animal species of a particular region or period are called fauna.

 

Endemic and Exotic species.

 

 *The natural vegetation which are purely Indian are known as endemic or indigenous species.

*Natural vegetation which have come from outside India are termed as exotic plants.

 

Extinct and endangered species.

*Extinct species of plants and animals are those which have completely disappeared from our forest whereas endangered species are those which are on the verge of extinction.

*About 1300 plant species are endangered and 20 species are extinct.

Ecosystem

*All the plants and animals in an area are interdependent and interrelated to each other in their physical environment.

* This interdependence and interrelationship forms an ecosystem.

 

*Human beings are an integral Part of the ecosystem.

* They utilise the vegetation and wildlife.

The greed of human beings leads to over utilisation of these resources. They cut the trees and kill animals creating an ecological imbalance.

 

 

Biome.

 A very large ecosystem on land having distinct types of vegetation and animal life is known as a biome.

Biomes are identified on the basis of plants.

Importance  of natural vegetation

*The importance of natural vegetation Forests modify local climate, control soil erosion, regulate stream flow, support a variety of industries, provide livelihood for many communities and offer panoramic view for recreation.

*It controls wind force, regulate temperature and causes rainfall. It also provides humus on the soil and shelter to the wild life.

India’s a rich heritage of flora and fauna

India is rated as one of the twelve mega biodiversity country of the world

b. India has 47000 plant species and 89000 species of animals.

c. India is tenth in the world and fourth in Asia in plant diversity.

d. India has 15000 flowering plants. They constitute 6% of the world’s total flowering plants.

e. India is also rich in non-flowering plants that include fern, algae, and fungi.

f. India has a huge variety of fishes in its fresh and marine waters.

 

Topic: Factors Affecting Natural vegetation

 

 Causes OF Biodiversity

 

*India has a rich heritage of fauna and flora as geographically the country has a very wide range of physical, climatic and soil conditions.

Our tradition of respecting all forms of life has also contributed to the preservation of plant and animal species over the centuries.

 

Factors which affect the diversity of flora and fauna:

 

v Relief

v Land: Land directly and indirectly affects the natural vegetation. Nature of land influences the type of vegetation. If the land is level and fertile, it is mainly used for farming. If the land is uneven then grassland and woodlands develop over it. Fertility , slope, settlement

v Soil: Different types of soil are fit for different types of vegetation. For example; sandy soil is fit for cactus and thorny bushes, while wet and marshy soil is fit for mangrove vegetation.

v Climate : Temperature and Humidity: Temperature and humidity are the main factors which determine the character and extent of vegetation. An area with high temperature and high humidity supports evergreen forest, while an area with high temperature and low humidity supports thorny bushes.

 

v Photoperiod (Sunlight): The duration of sunlight is called photoperiod. Photoperiod depends on latitude, altitude, season and duration of the day. Trees grow faster in summer because of longer photoperiod.

 

v Precipitation: If an area gets heavy rainfall, it is suitable for the growth of dense vegetation. On the other hand, an area with scanty rainfall is suitable for thorny bushes.

 

Types of vegetation

 

There are five major types of vegetation in India:

v Tropical Rainforests

v Tropical Deciduous Forests

v Tropical Thorn Forests and Scrubs,

v Montane Forests

v Mangrove Forests.

 

Tropical Rain Forests

 

v *The tropical rainforests are found in the areas of heavy rainfall.

Such areas are in the Western Ghats, Assam, Tamil Nadu coast and the island groups of Lakshadweep and Andaman & Nicobar.

v Areas which receive more 200 cm of rainfall and have a short dry season are the best area for tropical rainforest.

 

 

 

 

 

v Almost all kinds of vegetation; like trees, shrubs and creepers are found in such a forest.

v The forest has a multilayered structure. 4 layers

v Ebony, mahogany, rosewood, rubber and cinchona are the commercially important trees of tropical rainforests.

v Elephants, monkey, lemur and deer are the common animals in these forests.

v Apart from them, a large number of birds, bats, sloth, scorpions and snails are also found in tropical rainforests.

 

Tropical Deciduous Forests

 

v Tropical deciduous forests are the most widespread forests of India. regions which get rainfall between 200 cm and 70 cm are the best area for tropical deciduous forest. *They are also called the monsoon forests.

v The trees of tropical deciduous rainforests shed their leaves during summer.

v These forests can be divided into two types on the basis of availability of water.

v Economic importance

 

Moist Deciduous Forest: 

 

v The moist deciduous forests are found in areas which receive rainfall between 200 cm and 100 cm.

v Such forests are found mainly in the eastern part of India; like northeastern states, along the foothills of the Himalayas, Jharkhand, West Orissa and Chhattisgarh.

v They are also found on the eastern slopes of the Western Ghats.

(b)Dry Deciduous Forest:

 

v The dry deciduous forests are found in those regions which receive rainfall between 100 cm and 70 cm.

v Such forests are found in the rainier parts of the peninsular plateau and the plains of Bihar and Uttar Pradesh.

v Teak, bamboo, sal, shisham, sandalwood, khair, kusum, arjun, mulberry are some of the commercially important trees in these forests. Lion, tiger, pig, deer and elephant are the common animals in these forests.

v Additionally, a large variety of birds, lizards, snakes and tortoises are found in these forests.

The Thorn Forests and Scrubs

 

v Thorn forests grow in those regions which receive less than 70 cm of rainfall.

v This type of vegetation is found in the north-western part of India, e.g. Gujarat, Rajasthan, Madhya Pradesh, Chhattisgarh, Uttar Pradesh and Haryana.

v The main plant species in such a forest are acacia, palms, euphorbias and cactus.

v The trees are scattered and they have long roots which go very deep in the ground. The stems are succulent to conserve water. Leaves are usually modified into thorns to prevent evaporation.

v Camel, rats, mice, rabbits, fox, wolf, tiger, lion, wild ass, horse, etc. are the common animals in thorny forests.

 

Montane Forests

 

*The forests in the mountainous areas are called montane forest. Different types of vegetation are found at different altitudes in the mountains.

 

(a) The wet temperate type of forest is found between a height of 1000 and 2000 metres.

 Evergreen broad-leaf trees such as oak and chestnut abound in such forests.

(b) Temperate forests are found between the heights of 1500 and 3000 metres.

 Coniferous trees; like pine, deodar, silver fir, spruce and cedar abound in such forests.

(c) Alpine vegetation are found are heights of more than 3600 metre. These forests are mainly found along the southern slopes of the Himalayas and at high altitudes in southern and north-eastern India.

*Kashmir stag, spotted deer, wild sheep, jack rabbit, Tibetan antelope, yak, snow leopard, squirrels, Shaggy horn wild ibex, bear, rare red panda, sheep and goats are the common animals in these forests.

 Mangrove Forests

*Mangrove forests are found in the deltas of the Ganga, the Mahanadi, the Krishna, the Godavarai and the Kaveri.

w.bengal , tamilnadu , tsunai

 *The deltaic areas with clayey soil and saline water during tides have mangrove forests.

The plants of these areas have adapted themselves to the alteration of freshwater and saline water as well as to the sticky mud and silt.

 *Roots of the mangrove plants are submerged under water. Hollow roots grow out vertically above water so that roots can breathe.

*The forest are dense with hardwood trees like sundari, keora, agar, palm and coconut in some parts. Sundari tree is the most common tree in such forests; especially in the Sunderban Delta.

*Royal Bengal Tiger is the most famous animal of these forests. Additionally, turtles, crocodiles, gharials and snakes are found in these forests.

 Natural Vegetation: Challenges & Effects

Importance of forests

 

 (1) The raw materials for paper industry, match making, gums and resins are also extracted from the forest products.

(2) They help in controlling soil erosion.

(3) They help in enhancing the quantity of rainfall.

(4) They provide certain types of herbs which are in turn used to produce useful medicines.

(5)they play key role in the ecological system as they are the primary producers on which all other living being depend .

(6)forest communities directly depend on them for their food ,drink, medicine, culture.

Causes of depletion of forests

v Forests are gradually depleting. A number of plants and animal species have already become extinct and many are endan­gered.

v A large number plant species in India is in the endangered list.

v 47,000 species of flora 15,000 flowering species are endemic to India

The different factors responsible for the depletion of biodiversity.

 (causes of environmental degradation )

(1)  Expansion of railways.

(2)  Conversion of forest land into agricultural land

(3) Mining**

(4)  Large Scale development projects

(5 Grazing and fuel wood collection

(6) Commercial and scientific forestry.

(7) Forest fires has led to the depletion of biodiversity

(8) Environmental pollution- air pollution, Water pollution, industrial pollution, pollution due to chemical Pastes, pesticides radioactive materials are responsible for ……………

(9) Expansion of agriculture. Over use of fertilizers chemicals and over irrigation have resulted in land degradation

(10)- Over-exploitation of natural resources

Over-exploitation of natural resources for meeting human needs.

11 Introduction of exotic species:some exotic species may kill or eat the native species thereby causing its extinction.

12 -The shifting or Jhum cultivation Overgrazing

 

Adverse effects of the destruction of forests

 

(i) Destruction of forests leads to disturbances in ecological balance of the environment.

(ii) It also affects the cultural loss of communities and their displacement.

(iii) It also disturbs food chain, ecosystem and development of the society .

(iv)Poverty – Deforestation is also responsible for poverty  It has also resulted in severe droughts and floods which has affected forests communities very badly.

(You can add more from book )

 

Topic: Wildlife in India

Wildlife diversity in India

 

Like its flora, India is also rich in its fauna. It has approximately 90,000 animal species.

v The country has about 2,000 species of birds. They constitute 13% of the world’s total.

v There are 2,546 species of fish, which account for nearly 12% of the world’s stock.

v It also shares between 5 and 8 per cent of the world’s amphibians, reptiles and mammals.

National Parks

National Park: These are the reserved forests where natural vegetation and wildlife are preserved in their natural environment.

These parks are created and protected by the government.

According to IUCN national park should cover minimum 1000 Hectares. There are around 7000 national parks in the world.

 Eg. Kaziranga National Park.

2. Wildlife Sanctuary: These are the portion of the natural forests where hunting and poaching of wild animals and birds are prohibited.

In wild life sanctuaries wild life their habitat are preserved

 Eg. Bharatpur Bird Sanctuary

3. Biosphere Reserve: The forest areas where all types of flora and fauna are preserved in their natural environment.

 

WILD LIFE

 

v Elephants are found in the hot wet forests of Assam, Karnataka and Kerala.

v One-horned rhinos are found in the swampy and marshy lands of Assam and West Bengal.

v The In the freezing climate of Himalayas specially in Ladakh following animals can survive in extreme cold climate at high altitudes

*Yak,                               *Shaggy horned wild ox

* Tibetan antelope       * Bharal (blue sheep)

*Wild sheep                   *Kiang (Tibetan wild ass).

*Ibex                               *Bear

*Snow-leopard              *Red panda

 

v *Wild ass and camels are found in the Rann of Kachchh and Thar Desert. Indian bison, nilgai, chousingha, gazel and many other species of deer and some other animals are found in India.

v India is the only country in the world which has both tigers and lions.

v Bird life in India is colourful . Peacocks, pheasants, ducks, parakeets, cranes and pigeons are some of the birds inhabiting the forests and wetlands of the country.

 

Major threats to wildlife

*The major threat to wild is hunting by greedy hunters for commercial purposes.

*Pollution due to chemical and industrial waste, acid deposits, introduction of alien species.

*Reckless cutting of the forests to bring land under cultivation and inhabitation.

 

Topic: Natural vegetation & Wild life conservation

Classification of Species

 

Extinct Species

(1) These species no longer exist on Earth.

(2) They are already missing and their survival is

Suspicious.

(3)  Examples: Asiatic cheetah, pink headed Duck, etc.

 

Endangered Species

(1) These are species which are in danger of

extinction.

(2) Their population is fast dwindling.

 (3) Examples: Blackbuck, wild ass, Indian rhino,

Crocodile, lion-tailed macaque etc.

 

 

Vulnerable Species: Their population has decreased to the level of being endangered in the near future.

  E.g. Asiatic elephant, blue sheep, Gangetic dolphin etc.

 

 

Rare Species: Species those are very small in number. May become endangered or vulnerable in future.

E.g.  Hornbill, Himalayan brown bear, wild Asiatic buffalo, desert fox etc. 

 

Endemic Species: The species that are found only in a particular region and are isolated by natural barriers are called endemic species.

    Andaman teal, Nicobar pigeon, Andaman wild pig etc.

 

 

 

 

 

Reason for extinction

 

v Endangered species are those species of flora and fauna which are in the danger of extinction.

v In India, about 1,300 plant species are endangered. Quite a few animal species, like the one horned rhino, Indian tiger, Indian wild ass, black buck, red panda, Asiatic elephants, Indian bustard, are endangered.

v The main causes that have led to threat upon. India’s flora and fauna, endangering many species are:

(i) Hunting and poaching for illegal trade of animal tusks, horns, bones, skin, etc.

(ii) Reckless cutting of forests to bring land under cultivation and settlement have destructed the natural habitats of wild creatures and wiped off valuable species of trees.

(iii) Pollution due to chemical and industrial waste, acid deposits, have brought down numbers of plants and animals.

Commercial exploitation of forestlands has also reduced space for animal habitats.

  (iv) Introduction of alien species that may be hostile to existing native species.

Government steps to conserve flora and fauna of India

v Wildlife crime control bureau

v Green belt program

v Central and state Governments, NGOs, wildlife organizations and volunteers are continuously working to protect wildlife and plants.

v Following steps have been taken by the government to protect the flora and fauna of the country.

v Government established biosphere reserves.

v There are fourteen biosphere reserves in India.

v Presently(in March 2020 ) total number of biospheres in India are 18.

v Four out of these, the Sunderbans in the West Bengal, Nanda Devi in Uttaranchal, the Gulf of Mannar in Tamil Nadu and the Nilgiris (Kerala, Karnataka and Tamil Nadu) have been included in the world network of Biosphere reserves.

v The fourteen biosphere reserves are: Sunderbans, Gulf of Mannar, the Nilgiris, Nanda Devi, Nokrek, Great Nicobar, Manas, Simlipal, Dihang-Dibang, Dibru Saikhowa, Agasthyamalai, Kanchenjunga, Pachmari, Achanakmar-Amarkantak.

v Project Tiger, Project Rhino, Project Great Indian Bustard and many other eco developmental projects have been introduced.

v 89 National Parks, 49 Wildlife sanctuaries and Zoological gardens are set up to take care of Natural heritage.

v Bio-reserves are intended to protect and conserve the diverse flora and fauna found within the country.

v In these reserves every plant and animal species is protected in its natural form.Wildlife Protection Acts to safeguard wildlife.

v Afforestation, social programmes and awareness campaigns can also help to protect endangered species.

 

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