Biodiversity: -
Biodiversity itself is a combination of two words, Bio (life) and diversity (variety). In simple terms, biodiversity is the number and variety of organisms found within a specified geographic region. It refers to the varieties of plants, animals and micro-organisms, the genes they contain and the ecosystems they form. It relates to the variability among living organisms on the earth, including the variability within and between the species and that within and between the ecosystems. Biodiversity is our living wealth. It is a result of hundreds of millions of years of evolutionary history.
The different levels of biodiversity: -
Biodiversity can be discussed at
three levels: (i) Genetic diversity; (ii) Species diversity; (iii) Ecosystem diversity.
(a) Genetic Diversity - Genetic biodiversity refers
to the variation of genes within species. Groups of individual organisms
having certain similarities in their physical characteristics are called species.
Human beings genetically belong to the homo sapiens group
and also differ in their characteristics such as height, colour, physical
appearance, etc., considerably. This is due to genetic diversity. This genetic
diversity is essential for a healthy breeding of population of species.
(b) Species Diversity - This refers to the
variety of species. It relates to the number of species in a defined area.
The diversity of species can be measured through its richness, abundance and
types. Some areas are richer in species than others. Areas rich in species
diversity are called hotspots of diversity.
(c) Ecosystem Diversity - Differences between ecosystem types and the diversity of habitats.
Biodiversity Hotspots: -
Areas rich in species diversity
are called hotspots. Hotspots are defined according to their
vegetation. Plants are important because these determine the primary
productivity of an ecosystem.
There are some countries which
are situated in the tropical region; they possess a large number of the
world’s species diversity. They are called mega diversity centres.
There are 12 such countries, namely Mexico, Columbia, Ecuador, Peru,
Brazil, Democratic Republic of Congo, Madagascar, China, India, Malaysia,
Indonesia and Australia in which these centres are located.
 |
| Biodiversity Hotspots |
The importance of animals to human kind: -
Animals are important for human
kind because they provide food (milk and meat), fiber (Wool) and Skin after
their death as a variety of leather garments. Human beings use pet animals as a
medium of transportation from a long time in the history as well as today.
Animals help us in agriculture. Animals are the social status for human
kind.
Animals are important for human
existence. All forms of life are so closely interlinked that disturbance in one
gives rise to imbalance in the others. If species of plants and animals become
endangered, they cause degradation in the environment, which may threaten human
being’s own existence.
The role of biodiversity in the shaping of nature: -
Biodiversity has contributed in
many ways to the development of human culture and, in turn, human communities
have played a major role in shaping the diversity of nature at the genetic,
species and ecological levels. Biodiversity plays the following roles:
ecological, economic and scientific.
(a)
Ecological Role of Biodiversity - Every organism, besides
extracting its needs, also contributes something of useful to other organisms.
Species capture and store energy, produce and decompose organic materials, help
to cycle water and nutrients throughout the ecosystem, fix atmospheric gases
and help regulate the climate. These functions are important for ecosystem
function and human survival.
(b)
Economic Role of Biodiversity - For all humans,
biodiversity is an important resource in their day-to-day life. One important
part of biodiversity is ‘crop diversity’, which is also called agro-biodiversity.
Biodiversity is seen as a reservoir of resources to be drawn upon for the
manufacture of food, pharmaceutical, and cosmetic products. Some of the
important economic commodities that biodiversity supplies to humankind are:
food
crops, livestock, forests, fish, medicinal resources, etc.
(c)
Scientific Role of Biodiversity - Biodiversity is
important because each species can give us some clue as to how life evolved and
will continue to evolve. Biodiversity also helps in understanding how life
functions and the role of each species in sustaining ecosystems of which we are
also a species. This fact must be drawn upon every one of us so that we live
and let other species also live their lives.
It is our ethical responsibility
to consider that each and every species along with us have an intrinsic right
to exist. Hence, it is morally wrong to voluntarily cause the extinction of any
species. The level of biodiversity is a good indicator of the state of our
relationships with other living species. In fact, the concept of
biodiversity is an integral part of many human cultures.
The major factors responsible for the loss of biodiversity
Since the last few decades, growth
in human population has increased the rate of consumption of natural
resources. It has accelerated the loss of species and habitation in
different parts of the world. Over-exploitation of resources and deforestation
are the other major factors that are responsible for the loss of biodiversity. Natural
calamities such as earthquakes, floods, volcanic eruptions, forest
fires, droughts, etc. cause damage to the flora and fauna of the earth,
bringing change the biodiversity of respective affected regions. Pesticides
and other pollutants such as hydrocarbons and toxic heavy metals destroy
the weak and sensitive species.
Exotic species: -
Natural calamities such as
earthquakes, floods, volcanic eruptions, forest fires, droughts, etc. cause
damage to the flora and fauna of the earth, bringing change the biodiversity of
respective affected regions. Pesticides and other pollutants such as
hydrocarbons and toxic heavy metals destroy the weak and sensitive species. Species
which are not the natural inhabitants of the local habitat but are introduced
into the system are called exotic species. There are many examples
when a natural biotic community of the ecosystem suffered extensive damage
because of the introduction of exotic species. During the last few decades,
some animals like tigers, elephants, rhinoceros, crocodiles, minks and birds were
hunted mercilessly by poachers for their horn, tusks, hides, etc. It has
resulted in the rendering of certain types of organisms as endangered category.
Conservation of Biodiversity:-
Biodiversity is important for
human existence. There is an urgent need to educate people to adopt
environment-friendly practices and reorient their activities in such
a way that our development is harmonious with other life forms and is
sustainable. There is an increasing consciousness of the fact that such conservation
with sustainable use is possible only with the involvement and
cooperation of local communities and individuals. For this, the development
of institutional structures at local levels is necessary.
The steps
needed to prevent the loss of biodiversity: -
The Government of India along with
155 other nations has signed the Convention of Biodiversity at the Earth
Summit held at Rio de Janeiro, Brazil in June 1992. The world
conservation strategy has suggested the following steps for biodiversity
conservation:
(i) Efforts should be made to preserve
the species that are endangered.
(ii) Prevention of extinction
requires proper planning and management.
(iii) Varieties of food crops,
forage plants, timber trees, livestock, animals and their wild relatives should
be preserved;
(iv) Each country should
identify habitats of wild relatives and ensure their protection.
(v) Habitats where species feed,
breed, rest and nurse their young should be safeguarded and protected.
(vi) International trade in wild
plants and animals be regulated.