Biodiversity -For a world without hunger
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Transcript of Biodiversity -For a world without hunger
Biodiversity refers to the totality of
genes, species and ecosystems of a region.
The term Biodiversity was popularised
by the the sociobiologist Edward Wilson.
It is the assemblage of different life
forms.
It is also be defined as the number of
different organisms and their relative
frequency in an ecological system.
Biodiversity differs from place to place
SIGNIFICANCE OF BIODIVERSITY
Biodiversity, besides its ecological significance provides a socio-
economic and monetary asset to the Nation.
Human society depends on biological resources.
It provide essential goods and services for mankind.
Values related to biodiversity can be grouped into three categories;
a) Productive Use
b) Consumptive Use
c) Indirect Use
PRODUCTIVE USE
This is assigned to products that are
commercialy harvested for exchange
in formal markets.
Here the only value of biological
resources is that is concerned in
National income.
Biodiversity provides us many
products such as fuel, timber, fish,
fodder, skin, fruits, cerals and
medicinal plants.
CONSUMPTIVE USE
Consumption value is
related to natural products that
are consumed directly that is
the goods donot come under
normal circulation of trade.
Non –timber forest products
as soft broom grass and cane
under this category.
INDIRECT USE
They may provide us indirect
benefits as non-consumptive
values such as maintenance of
ecological balance,
conservation of natural
resources, and preservation of
soil erosion may be considered
as the examples of indirect use
of biodiversity.
TYPES OF BIODIVERSITY
Biodiversity includes three hierarchial
levels. They are;
a) Genetic diversity
b) Spcies diversity
c) Ecosystem diversity
These levels of biodiversity are
interrelated. Their interconnections
support the life form earth.
Genetic diversity refers to the
variation of genes within the species
and the variation occures at the levels
of alleles or entire genes of
chromosomes. The genetic diversity
helps a population to adapt to its
environment. If a species has more
genetic diversity it can adapt better to
the changed environmental condition.
Genetic variation results in the
species variation.
Species diversity diversity means the
variety of species within a region. Species
are distinct unit of diversity. Loss of
species leads to serious consequences
affecting the total ecosystem. Simplest
measure of species diversity is species
richness, which is the number of species
per unit area.
Ecosystem diversity deals with the number of niches, trophic
levels and various ecological processes that sustain energy flow,
food webs and the recycling of nutrients. The number ecosystems
varies within a geographical area.
HOT SPOTS OF DIVERSITY
Areas that are rich in species diversity are
called hot spots. There are over a
thousand major “ecoregions” in the world.
Contries which have a large area of
biodiversity hot spots are refered as
‘Mega-diversity nations’. Our globally
accepted national hotspots are in the forest
of Western Ghats, Himalaya, which are
included in the world’s most bio-rich
areas. The Andaman and Nicobar Islands
are extremly rich in species diversity.
THREATS OF BIODIVERSITY
Natural calamities such as flood,
drought, storms, forest fire,
volcanic eruptions, epidemics etc
are all threats to biodiversity
Artificial causes such as habitat
loss, over exploitation, pollution,
introduction of exotic species,
poaching of wild life & man and
wildlife conflict.
HABITAT LOSS: Distruction of is the primary reason for the
loss of biodiversity. The natural habitat of some species is
distroyed by cutting down trees, burning forest filling of wet
lands. These activities can kill many plants, animals and micro
organisms etc.
OVER EXPLOITATION: It is an another
cause for extinction. Over exploitation of
particular species reduces the size of its
population to an extent that it become
vulnerable to extinction. Ex: Indian cheetah,
Mauritian bird Dodo.
POLLUTION: Environmental pollution
may reduce and eliminate population of
sensitive species.
INTRODUCTION OF EXOTIC SPECIES:
New species entering a geographical area
are called exotic species. Introduction of
exotic species causes changes in biotic
interactions leading to disappearence of
native species. Intoduction of such invasive
species are considered second only to
habitat destruction as a major cause of
extinction of species
POACHING OF WILD LIFE : Specific threat to certain
animals are related to large economic benefits. The skin of bones
from tiger, ivory from Elephants, perfumes from musk deer are
extensively used abroad. Bears are killed for their gall bladder.
Corals and shells are also collected for export.
MAN-WILDLIFE CONFLICT:
Man and wildlife conflict is another reason for depletion
of biodiversity. Co-existence of man and wildlife exists in
certain areas and that will enhance biodiversity
METHODS OF CONSERVATION OF BIODIVERSITY
The concept of conservation of
biodiversty encomposes protection and
sustained use of all genetic resources
whether it is wild or domestic.
There are two methods of conservation
of biodiversity;
a) In-situ conservation (on site)
b) Ex-situ conservation (off site)
In-situ conservation
It means the conservation of
ecosystem and natural habitat,
and the maintenance and
recovery of vulnerable
populations or species in their
natural surroundings.
Protected areas such as
National parks, Wild life
sanctuaries, biosphere reserve
are the important needs of in-situ
conservation.
NATIONAL PARKS
It is an area which is strictly preserved for
the betterment of the wildlife where
activities such as foresting, grazing or
cultivation not permitted.
No private ownership right is allowed.
Yellow stone national park is the first
national park in the world (1872).
Northest greenland national park (1974) is
the largest national park in the world.
Ex:Jim Corbet National Park – Tiger - UP
Eravikulam National Park- NilgiriTahr-kerala
WILDLIFE SANCTUARIES
It is an area where protection of certain
species get much emphasis.
Sanctuaries provide protection and
optimum living condition to wild animals.
A sanctuary is created by order of a
competent authority
Ex: PeparaWildlife sanctuary
Neyyar
Parambikulam
BIOSPHERE RESERVES
They are protected areas where all biological species, including
wild population native tribals, cultivated plants and domesticated
animals are given in protection and multiple land use is permitted.
Biosphere are the larger protected areas of natural habitat.
They include one or more national park and wildlife sanctuaries.
In India there are 15 Biosphere reserves.
Ex: Nilgiri biosphere reserve – Kerala, TamilNadu, Karnataka
Nanda Devi Biosphere Reserve – UP
Uttarkhand Biosphere Reserve – North-West Himalayas
Ex-situ Conservation
It means the conservation of components of
biological diversity outside their natural
habitats.
Endangered species and those are at the
verge of extinction are protected here.
Ex: Botanical gardens
Zoological park (ZOO)
Gene bank Gene plasm bank
Breeding program