Natural Vegetation – The naturally growing plant cover without human aid is called natural vegetation.
Natural vegetation refers to a plant community which has naturally without human aid and has been left undisturbed by humans for a long time.
Our country India is one of the twelve mega bio-diversity countries of the world.
With about 47000 plant species India occupies tenth place in the world and fourth in Asia in plant diversity.
There are about 15,000 flowering plants in India which account for 6 percent in the world’s total number of flowering plants.
The country has many non flowering plants such as ferns, algae and fungi.
India also has 90,000 species of animals as well as rich variety of fish in its fresh and marine waters.The term flora is used to denote plants of a particular region or period.
Similarly, the species of animals are referred to as fauna.
This huge diversity in flora and fauna kingdom is due to the following factors.
Virgin vegetation – The vegetation which has been left undisturbed by humans for a long time is called virgin vegetation.
Do you know?
The virgin vegetation, which are purely Indian are known as endemic or indigenous species but those which have come from outside India are termed as exotic plants.
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.
Factors which affect the diversity of flora and fauna:
Relief – The difference between highest and the lowest points of elevation or height is called relief.
Land
Land affects the natural vegetation directly and indirectly.
The nature of land influences the type of vegetation.
The fertile level is generally devoted to agriculture.
The undulating and rough terrains are areas where grassland and woodlands develop and give shelter to a variety of wild life.
Soil
Different types of soils provide basis for different types of vegetation.
The sandy sot of the desert support cactus and thorny bushes while wet, marshy, deltaic soils support mangroves and deltaic vegetation.
The hill slopes with some depth of soil have conical trees.
Climate – The average weather in a given area over a longer period of time is called climate.
Temperature
The character and extent of vegetation are mainly determined by temperature along with humidity in the air, precipitation and soil.
On the slopes of the Himalayas and the hills of the Peninsula above the height of 915 metres, the fall in temperature affects the types of vegetation and its growth, and changes it from tropical to subtropical temperats and alpine vegetation.
Photoperiod (Sunlight)
The variation in duration of sunlight at different places is due to differences in latitude, altitude, season and duration of the day.
Due to longer duration of sunlight tress grow faster in summer.
Precipitation
In India almost the entire rainfall is brought in by the advancing southwest monsoon (June to September) and retreating northeast monsoons.
Areas of heavy rainfall have more dense vegetation as compared to other areas of less rainfall.
Why forest is important for human being?
Forest is renewable resources and plays a major role in enhancing the quality of environment.
They modify local climate, control soil erosion, regulate stream flow support a variety of industries, provide livelihood for many communities and offer panoramic or scenic view for recreation.
It control wind force and temperature and causes rainfall.
It provides humus to the soil and shelter to the wild life.
India’s natural vegetation has undergone many changes due to several factors such as the growing demand for cultivated land.
The vegetation cover of India in large parts is no more natural in the real sense.
Except in some inaccessible regions like the Himalayas, the hilly region of central India and the Marusthali, the vegetation of most of the areas has been modified at some places or replaced or degraded by human occupancy.
Do you know?
According to India State of Forest Report 2011, the forest cover in India is 21.05 per cent.
Ecosystem – A geographic area where plants, animals, and other organisms, as well as weather and landscape, work together to form a bubble of life is called ecosystem.
Plants occur in distinct groups of communities in areas having similar climatic conditions.
The nature of the plant in an area, to a large extent, determines the animal life in that area.
When the vegetation is altered, the animal life also changes.
All the plants and animals is an area are interdependent and interrelated to each other in their physical environment, thus, forming an ecosystem.
Human beings are also an integral part of the ecosystem.
They utilise the vegetation and wild life.
The greed of human beings leads to over utilisation of these resources.
They cut the tress and kill the animals creating ecological imbalance.
As a result some of the plants and animals have reached the verge of extinction.
A very large ecosystem on land having distinct types of vegetation and animal life is called a biome.
Types of vegetation: The following major types of vegetation may be identified in our country –
- Tropical Evergreen Forests
- Tropical Deciduous Forests
- Tropical Thorn Forests and Scrubs
- Mountain Forests
- Mangrove Forests
Tropical Evergreen:
They are at their best in areas having more than 200 cm of rainfall with a short dry season.
In these forest trees grow up to 60 m & above.
These forest yield hard wood trees.
These forests are found in rainy parts of Western Ghats, Assam, West Bengal. Lakshadweep and Andaman & Nicobar Islands.
Ebony, Mahogany, Rosewood, Rubber and Cinchona are some of the important trees.
In this forest large number of plant species is found at one place.
It creates difficulty in their commercial exploitation.
Elephants, Monkey, Lemur and Deer are some common animals found in these forests.
Tropical Deciduous Forest:
Tropical deciduous forests are the most widespread forests of India.
They are spread in those regions which get rainfall between 200 cm and 70 cm.
They are also called the monsoon forests.
The trees of tropical deciduous rainforests shed their leaves during summer.
These forests can be divided into two types on the basis of availability of water –
Moist Deciduous
These forests are found in the areas of 100 cm to 200 cm of rainfall.
Due to a longer dry season, the trees shed their leaves during the dry season.
Shisham, Bamboos, Sandalwood, Khair, Kusum, Arjun, Mulberry and Sal are the common trees found in these forests.
These forests cover a vast area of the country.
Northeastern States, along the foot hills of the Himalayas, Jharkhand, West Odisha and Chhattisgarh and on the Eastern Slopes of the Western Ghats.
Dry Deciduous
These are found in areas having rainfall between 70 cm to 100 cm.
These are found in the rainier part of peninsular plateau and the plains of Bihar and U.P.
These are open stretches in which Teak, Sal, Peepal, Neem grow.
Most of these forests have been cleared for cultivation. In these forests, the common animals found are lion, tiger, pig, Deer and elephant.
A huge variety of birds, lizards, snakes, and tortoises are also found here.
The Thorn Forest and Shrubs/Scrubs:
They are so called due to the dominance of thorny trees, bushes and scrubs.
These trees and bushes have long roots which spread in radial pattern, thick bark, sharp thorns and waxy leaves.
These devices help them to preserve water and protect themselves from animals
Tropical thorn forests occur in the areas which receive rainfall less than70 cm.
These consist of a variety of grasses and shrubs.
In includes semi-arid areas of south west Punjab, Haryana, Rajasthan, Gujarat, Madhya Pradesh and Uttar Pradesh.
In these forests, plants remain leafless for most part of the year and give an expression of shrub vegetation.
Important species found are babul, Kher and Wild Date Palm, Kikar, Neem,Khejn, Palas, etc.
Mountain forests:
In mountainous area, the decrease in temperature with increasing altitude leads to the corresponding changes in natural vegetation.
The wet temperate type of forest is found between heights of 1000and 2000 meters.
Evergreen broad-leaf tress such as oaks and chestnuts predominate.
Between 1500 and 3000 meters, temperate forests containing coniferous trees like pine, deoder, silver fir, spruce and cedar, are found.
These forests cover mostly the southern slopes of the Himalayas, Places having high attitude in southern and north-east India.
At higher elevations, temperate grasslands are common.
At high altitudes, generally more than 3,600 meters above sea-level, temperate forests and grasslands give way to the Alpine vegetation.
Silver fir, junipers, pines and birches are the common trees of this forest.
Above Alpine vegetation Alpine grasslands are found.
These are used extensively for grazing by nomadic tribes like the Gujjars and the Bakarwals.
At higher altitudes, mosses and lichens form part of tundra vegetation.
The common animals found in these forests are Kashmir stag, spotted dear, wild sheep, jack rabbit, Tibetan antelope, yaks, snow leopard squirrels Shaggy horn wild ibex, bear and rare red panda, sheep and goats with thick hair.
Alpine vegetation:
Above coniferous forests, there lies the Alpine vegetation at an altitude of about 3,600 metres and above.
This is the tree lies in the Himalayas.
Mangrove forests:
These are found in the areas which are under the influences of tides having accumulated mud and silt.
Dense mangrove is the common varieties with roots of plants submerged under water.
These forests are found in the deltas of Ganga, Mahanadi, Godavari and Kaveri.
The most important tree is the Sundari tree after which the Sunderbans are named.
The tree provides hard, durable and strong wood which is used for building boats and boxes.
Royal Bengal Tiger is the famous animal in these forests.
Turtles, crocodiles, gharials and snakes are also found in these forests.
|
Type of Vegetation
|
Rainfall
|
Areas
|
Flora
|
Fauna
|
|
Rainforest
|
More than 200 cm
|
Western Ghats, North-eastern India, Islands
|
Ebony, mahogany, rosewood, rubber and cinchona
|
Elephants, monkey, lemur and deer
|
|
Deciduous Forest
|
70 to 100 cm
|
Bihar, UP, MP, W. Bengal, Maharashtra, etc.
|
Teak, bamboo, sal, shisham, sandalwood, khair, kusum, arjun, mulberry
|
Lion, tiger, pig, deer and elephant
|
|
Thorny Bushes
|
Less than 70 cm
|
Rajasthan, Gujarat
|
acacia, palms, euphorbias and cactus
|
Camel, rats, mice, rabbits, fox, wolf, tiger, lion, wild ass, horse, etc.
|
|
Montane Forest
|
N/A
|
Himalayas and North-east
|
Pine, deodar, fir, cedar, etc.
|
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
|
|
Mangrove Forest
|
N/A
|
Delta of Ganga, Mahanadi, Kaveri, Godavari
|
Sundari, Orchid
|
Royal Bengal Tiger
|
Wild life – Living things and especially mammals, birds, and fishes that are neither human nor domesticated is called wildlife.
Like its flora. India is also rich in its fauna.
It has more than 90,000 of animal’s species.
The country has more than 12000 species of birds.
They constitute 13% of the world’s total.
There are 2546 species of fish, which account for nearly 12% of the world’s stock.
It also shares between 5 and 8 per cent of the world’s amphibians, reptiles and mammals.
The elephants are the most majestic animals among the mammals.
These are found in the hot wet forests of Assam, Karnataka and Kerala.
One homed rhinoceroses are the other animals, which live in swampy and marshy lands of Assam and West Bengal.
Arid areas of the Rann of Kachchh and the Thar Desert are the habitat for wild ass and camels respectively.
Indian bison, nilgai (blue bull), chousingha(four homed antelope), gazel and different species of deer are some other animals found in India.
It also has several species of monkeys.
India is the only country in the world that has both tigers and lions.
The natural habitat of the Indian lion is the Gir forest in Gujarat.
Tigers are found in the forests of Madhya Pradesh, the Sundarbans of West Bengal and the Himalayan region.
Leopards too are members of the cat family.
They are important among animals of prey.
Do you know?
Wildlife Protection Act was implemented in 1972 in India.
The Gir Forest is the last remaining habitat of the Asiatic lion.
Conservation measures:
Due to excessive exploitation of the plants and animal resources by human beings, the ecosystem has been disturbed.
About 1,300 plant species are endangered and 20 species are extinct.
Quite a few animal species are also endangered and some have become extinct.
The main causes for this major threat to nature are hunting by greedy hunters for commercial purposes.
Pollution due to chemical and industrial waste, acid deposits, introduction of alien species and reckless cutting of the forests to bring land under cultivation and inhabitation, are also responsible for the imbalance.
To protect the flora and fauna of the country, the government has taken many steps:
Eighteen biosphere reserves have been set up in the country to protect flora and fauna.
Ten out of these, the Sundarbans Nanda Devi, the Gulf of Mannar,the Nilgiri, Nokrek, Great Nicobar, Manas, Simlipal, Pachmarhi and Achanakmar-Amarkantak have been included in the world network of biosphere reserves.
Financial and technical assistance is provided to many botanical gardens by the government since 1992 (Kachchh, Cold Desert, Seshachalam, Panna).
Project Tiger, Project Rhino, Project Great Indian Bustard and many other eco-developmental projects have been introduced.
103 National Parks, 535 Wildlife sanctuaries and Zoological gardens are set up to take care of natural heritage.
All of us must realise the importance of the natural ecosystem for our own survival.
It is possible it indiscriminate destruction of natural environment is put to an immediate end.
|
Eighteen Bio-reserves
|
|
Cold Desert,
Himachal Pradesh
|
Nokrek,
Meghalaya
|
Sundarban,
West Bengal
|
|
Nanda Devi, Uttrakhand
|
Panna, Madhya Pradesh
|
Seshachalam, Andhra Pradesh
|
|
Khangchendzonga,
Sikkim
|
Pachmarhi,
Madhya Pradesh
|
Agasthyamala, Karnataka-Tamil Nadu-Kerala
|
|
Dehang-Debang,
Arunachal Pradesh
|
Achanakmar-Amarkantak, Madhya Pradesh-Chhattisgarh
|
Nilgiri, Tamil Nadu-Kerala (First to be Included)
|
|
Manas,
Assam
|
Kachchh, Gujarat
(Largest Area)
|
Gulf of Mannar,
Tamil Nadu
|
|
Dibru-Saikhowa,
Assam
|
Similipal,
Odisha
|
Great Nicobar, Andaman & Nicobar Island
|
Migratory Birds:
Some of the wetlands of India are popular with migratory birds.
During winter, birds, such as Siberian Crane, come in large numbers.
One such place favourable with birds is the Rann of Kachchh.
At a place where the desert merges with the sea, flamingo with their brilliant pink plumage come in thousands to build nest mounds from the salty mud and raise their young ones.
It is one among many extraordinary sights in the country.
