20-09-2013, 02:31 PM
Biodiversity
Biodiversity.pdf (Size: 969.85 KB / Downloads: 107)
INTRODUCTION
The great variety of life on earth has provided
for man’s needs over thousands of years. This
diversity of living creatures forms a support sys-
tem which has been used by each civilization
for its growth and development. Those that used
this “bounty of nature” carefully and sustainably
survived. Those that overused or misused it dis-
integrated.
What is biodiversity?
Biological diversity deals with the degree of
nature’s variety in the biosphere. This variety can
be observed at three levels; the genetic variabil-
ity within a species, the variety of species within
a community, and the organisation of species
in an area into distinctive plant and animal com-
munities constitutes ecosystem diversity.
Definition:
‘Biological diversity’ or biodiversity is that part
of nature which includes the differences in genes
among the individuals of a species, the variety
and richness of all the plant and animal species
at different scales in space, locally, in a region,
in the country and the world, and various types
of ecosystems, both terrestrial and aquatic,
within a defined area.
BIOGEOGRAPHIC CLASSIFICATION OF
INDIA
Our country can be conveniently divided into
ten major regions, based on the geography, cli-
mate and pattern of vegetation seen and the
communities of mammals, birds, reptiles, am-
phibia, insects and other invertebrates that live
in them. Each of these regions contains a vari-
ety of ecosystems such as forests, grasslands,
lakes, rivers, wetlands, mountains and hills,
which have specific plant and animal species.
Option value
Keeping future possibilities open for their use is
called option value. It is impossible to predict
which of our species or traditional varieties of
crops and domestic animals will be of great use
in the future. To continue to improve cultivars
and domestic livestock, we need to return to
wild relatives of crop plants and animals. Thus
the preservation of biodiversity must also include
traditionally used strains already in existence in
crops and domestic animals.
HOTSPOTS OF BIODIVERSITY
The earth’s biodiversity is distributed in specific
ecological regions. There are over a thousand
major ecoregions in the world. Of these, 200
are said to be the richest, rarest and most dis-
tinctive natural areas. These areas are referred
to as the Global 200.
It has been estimated that 50,000 endemic
plants which comprise 20% of global plant life,
probably occur in only 18 ‘hot spots’ in the
world. Countries which have a relatively large
proportion of these hot spots of diversity are
referred to as ‘megadiversity nations’.
Biodiversity.pdf (Size: 969.85 KB / Downloads: 107)
INTRODUCTION
The great variety of life on earth has provided
for man’s needs over thousands of years. This
diversity of living creatures forms a support sys-
tem which has been used by each civilization
for its growth and development. Those that used
this “bounty of nature” carefully and sustainably
survived. Those that overused or misused it dis-
integrated.
What is biodiversity?
Biological diversity deals with the degree of
nature’s variety in the biosphere. This variety can
be observed at three levels; the genetic variabil-
ity within a species, the variety of species within
a community, and the organisation of species
in an area into distinctive plant and animal com-
munities constitutes ecosystem diversity.
Definition:
‘Biological diversity’ or biodiversity is that part
of nature which includes the differences in genes
among the individuals of a species, the variety
and richness of all the plant and animal species
at different scales in space, locally, in a region,
in the country and the world, and various types
of ecosystems, both terrestrial and aquatic,
within a defined area.
BIOGEOGRAPHIC CLASSIFICATION OF
INDIA
Our country can be conveniently divided into
ten major regions, based on the geography, cli-
mate and pattern of vegetation seen and the
communities of mammals, birds, reptiles, am-
phibia, insects and other invertebrates that live
in them. Each of these regions contains a vari-
ety of ecosystems such as forests, grasslands,
lakes, rivers, wetlands, mountains and hills,
which have specific plant and animal species.
Option value
Keeping future possibilities open for their use is
called option value. It is impossible to predict
which of our species or traditional varieties of
crops and domestic animals will be of great use
in the future. To continue to improve cultivars
and domestic livestock, we need to return to
wild relatives of crop plants and animals. Thus
the preservation of biodiversity must also include
traditionally used strains already in existence in
crops and domestic animals.
HOTSPOTS OF BIODIVERSITY
The earth’s biodiversity is distributed in specific
ecological regions. There are over a thousand
major ecoregions in the world. Of these, 200
are said to be the richest, rarest and most dis-
tinctive natural areas. These areas are referred
to as the Global 200.
It has been estimated that 50,000 endemic
plants which comprise 20% of global plant life,
probably occur in only 18 ‘hot spots’ in the
world. Countries which have a relatively large
proportion of these hot spots of diversity are
referred to as ‘megadiversity nations’.