What is Natural vegetation Or Virgin 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 termed as a virgin vegetation.
Huge diversity in flora and fauna kingdom is due to the
following factors.
Relief which include
Land and Soil.
Climate which include Temperature, photoperiod and
precipitation.
(a) land-
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.
(b) Soil- The sandy soils 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.
© Temperature- fall in the temperature affects the types of
vegetation and its growth, and changes it from tropical to subtropical
temperate and alpine vegetation.
(c) Photoperiod-
The variation in duration of sunlight at different places is due to differences
in latitude, altitude, season and duration of the day also affected typs of vegetation.
(d) Precipitation-
Areas of heavy rainfall have more dense vegetation as compared to other areas
of less rainfall.
Q why forests are important for
human beings?
Ans Forests are renewable
resources and play 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 controls wind force and
temperature and causes rainfall. It provides humus to the soil and shelter to
the wild life.
Ecosystem
All the plants and animals in 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.
Q How do the human beings
influence the ecology of a region?
Ans They utilize the vegetation
and wild life.
The greed of human beings leads to
over utilization of these resources.
They cut the trees and kill the
animals creating ecological imbalance.
As a result some of the plants and
animals have reached the verge of extinction.
Define Biome.
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
(i)
Tropical Evergreen Forests
(ii)
(ii) Tropical Deciduous Forests
(iii)
(iii) Tropical Thorn Forests
(iv)
(iv) Montane Forests
(v)
(v) Mangrove Forests.
Tropical Evergreen Forests.
Heavy rainfall (200cm) areas of the Western Ghats and the island
groups of Lakshadweep, Andaman and Nicobar, upper parts of Assam and Tamil Nadu coast.
trees reach great heights up to 60
metres or even above.
There is no definite time for
trees to shed their leaves. these forests appear green all the year.
Common trees are ebony, mahogany, rosewood,
rubber and cinchona.
The common animals are elephants,
monkey, lemur and deer. The one horned rhinoceros are found in the jungles of Assam and West Bengal .
Tropical Deciduous Forests.
They are also called the monsoon
forests and spread over the region receiving rainfall between 200 cm and 70 cm.
Forest-type
shed their leaves for about six to eight weeks in dry summer.
These forests exist, northeastern
states, along the foothills of the Himalayas, Jharkhand, West Orissa and
Chhattisgarh, and on the eastern slopes of the Western
Ghats .
Teak is the most dominant species
of this forest. Bamboos, sal, shisham, sandalwood, khair, kusum, arjun,
mulberry are other commercially important species.
