Biodiversity and conservation
Biodiversity can be defined as the summation of genes,
species and ecosystems of a given region.
This term was chased
by EDWARD WILSON
Diversity ranges
from macro-molecules to biomes.
Biodiversity can be
studied at-
1. Genetic diversity
2. Species diversity
3. Ecological/
Ecosystem diversity
1. GENETIC DIVERSITY
Greater the Genetic diversity
among organisms of a species, further food it has against environmental
disquiet.
Genetically invariant populations are largely prone to disease
harsh terrain.
Rauwolfia vomitoria shows Genetic variation in terms of attention
and energy of chemical reserpine
There are further than kinds of rice and nearly 1000 kinds
of mangoes.
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2. SPECIES DIVERSITY
Important measures-
1. Species
richness It refers to the number of species per unit area.
2. Species
Evenness It refers to the relative abundance with which each species is
represented in an area.
· The
variety and number of individualities determine the position of diversity of an
ecosystem.
· The
Western Ghats have a lesser diversity of amphibian species than the Eastern
Ghats.
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3. ECOLOGICAL DIVERSITY
Ecological Diversity is related to species diversity.
India has lesser ecosystem diversity than any other
Scandinavian country.
India has several biomes like alpine meadows, rain forests,
deserts, wetlands, mangroves …etc.
GLOBAL BIODIVERSITY
• According to the IUCN (2004) the total
number of plant and animal species is about1.5 million.
• Further than 70%
of the species recorded are creatures and plants regard for about 22%; 70% of
the creatures are insects.
• A further
conservative and scientifically sound estimate has been made by Robert May; it
puts the global species diversity at about seven million.
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These estimates don't give any figure for
prokaryotes for the following reasons
1. The conventional
taxonomic styles aren't sufficient for relating these microbial species
2. Numerous of these
species can not be dressed under laboratory conditions.
3. Biochemical and
molecular biology ways would put their diversity into millions.
BIODIVERSITY IN INDIA
• India is one of
the twelve mega biodiversity countries of the world.
India has only2.4 of the land area of the world, it has8.1 of the global species biodiversity.
• There are about
45,000 species of plants and about 90,000- 1,00,000 species of animals.
• New species are
yet to be discovered and named.
• Applying Robert
May’s global estimate, only 22% of the total species have been recorded, India
has presumably more than 1,00,000 species of plants and species of creatures to
be discovered and described.
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• Biodiversity isn't
invariant throughout the world but varies with latitude and altitude.
• Favorable
environmental conditions favor speciation and make it possible for a larger
number of species to live there, i.e., biodiversity is more in similar areas
than the others.
1.
Latitudinal Gradients
• Species diversity decreased from equator towards poles.
• The tropics harbor further species than temperate and
polar regions.
• Example- Colombia (near equator) has 1400 species of birds
whereas New York (41 ° N) has 105 species, Greenland (71 ° N) has 56 species
and India ( ambit region) has 1200 species.
VARIATION
OF SPECIES WITH LATITUDE
• The number of
species of vascular plants in tropics is about ten times further than that of
temperate timbers.
• Amazonian
Rainforest has the topmost biodiversity on earth. It has further than 40000
species of plants, species of insects, 300 species of fish, 427 of amphibian
and 378 of reptiles, 1300 species of birds and 427 of mammals.
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2. Species- Area Relationship
• Alexander Von
Humboldt has observed that within a region, species richness gets increased
when explored area is increased, but only over to a limit.
• The relationship
between species richness and area for a number of taxa like angiospermic plants,
fresh water fishes and birds is plant to be a rectangular hyperbola.
Graph
showing Species- Area Relationship
The equation is
described by –
log S = log C+Z log A
S – Species Richness
Z – Pitch of the
line (retrogression measure)
A – Area
C – y-intercept
Ecologists have
plant that Z value ranges between 0.1 &0.2 irrespective of the taxonomic
group or the region.
In veritably large area like mainlands, Z value ranges
between0.6 &1.2.
SIGNIFICANCE
OF SPECIES DIVERSITY TO ECOSYSTEM
Ecologists believe
that communities with further species tend to be more stable than those with
lower species.
Attributes
of a stable community-
1. It shall not show
too important of variations in the year-to- year productivity.
2. It must be either
resistant or flexible to seasonal disturbances.
3. It must be
resistant also to alien species.
Point of David Tilman’s ecology trials-
1. The plots with
further species showed less time-to- time variation in the total biomass.
2. Plots with
increased diversity showed advanced productivity.
Hence, we realize
that species richness and diversity are essential for ecosystem health as well
as survival of human race on earth.
LOSS OF BIO-DIVERSITY
• Caused by
Population, Urbanization and Industrialization.
• The colonization
of tropical Pacific Islands by human has led to the extermination of further
than 2000 species of native birds.
• 15,500 Species are
facing the trouble each around.
• At now 31%
gymnosperms, 32%amphibians,12% bird species and 23% of mammals face the
trouble.
• Loss of bio-diversity
in a region leads to
(1) Drop in plant
product.
(2) Lower resistance
to environmental disturbances similar as famines.
(3) Increases
variability in ecosystem processes like plant productivity, water use, pest and
disease cycles etc.
CAUSES
OF BIODIVERSITY LOSSES.
1. Habitat loss and
fragmentation
2. Over-exploitation
3. Alien species
irruption
4. Co-extinction
I. HABITAT LOSS AND FRAGMENTATION
• Destruction of
niche is the primary cause of extermination of species.
• The tropical
rainforests originally covered 14 of land but now only 6.
• The Amazon rain
timber is also called ‘‘The lungs of the earth ’’.
• When large sized
territories are broken or disintegrated due to human agreements, structures of
roads, digging of conduitsetc., creatures taking large homes and some creatures
with migrant territories are poorly affected.
ll. OVER-EXPLOITATION
• When natural
system is over exploited by man for the natural coffers, it results in
declination and extermination of the coffers, e.g. Steller’s ocean cow,
passenger chump etc.
III. ALIEN SPECIES Irruptions.
• Some alien
irruption has come invasive and causes maximum dangerous impact and the
extermination of the indigenous species.
• Preface of African
catfish for monoculture purposes is posing a trouble to the being species of
catfishes of Indian gutters.
IV. CO-EXTINCTIONS
• When a species
come defunct, the plant and animal species associated with it in an obligatory
manner, also come defunct.
• For example, if
the host fish species becomes defunct, all those spongers simply plant on it'll
also come extinct.
Recent
demolitions
· Quagga,
Africa
· The
Dodo Bird, Mauritius
· Thylanine,
Australia
· Steller’s
ocean cow.
· Dugong
suggesting the steller’s ocean cow
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BIO-DIVERSITY CONSERVATION
1. Narrowly utilitarian
• Humans derive a number of profitable benefits from nature
like food, wood, fibres, and medicines and further …
• Further than 25 of the medicines are deduced from plants
and further than species of plants are used by natives for medicine.
2.
Broadly utilitarian
• Biodiversity plays
an important part in maintaining and sustaining force of goods and services.
• Amazon timber
contributes 20 of the total oxygen in the atmosphere on earth.
• Pollination of plants
by furnishing pollinators, subcaste freak, birds and batonsetc.
Ethical
• There are thousands of plants, creatures and microbes on
this earth which aren't useless.
• Each bone has some
natural value indeed if it isn't of any profitable value to us.
• It's thus our
moral duty to insure well- being of all the living brutes for the application.
CONSERVATION
OF BIODIVERSITY
There are two
introductory approaches towards conservation of memoir diversity
• In situ conservation
• Ex situ conservation
I. In
situ conservation
a) Biosphere reserves: Out of 425
biosphere reserves in the world, 14 are in India. Hot spots are the areas/
regions of high endemism and veritably high situations of species richness.
There are 34 hot spots in the world, of which three are in India; videlicet
Western Ghats and Sri Lanka, Indo-Burma and Himalaya.
b) National premises and wildlife sanctuaries:
India has 90 citizens premises and 448 wildlife sanctuaries.
c) Sacred groves: These are timber
patches which were reverenced and given total protection. It includes a number
of rare, exposed and aboriginal species. Ex. Western Ghats, Khasi and Jaintia
Hills in Meghalaya.
II. Ex
situ conservation
India has 35 botanical auditoriums and 275 zoological
premises. By using Cryopreservation (-196o C) fashion, sperms, eggs, animal
cells, tissues and embryos can be stored for long period. Plants are propagated
by using towel culture styles called micropropagation.
CONVENTIONS
ON BIODIVERSITY
• The Earth
Summit-Rio de Janeiro, 1992.
• The World Summit,
South Africa 2002.
In the Summit, 190
countries pledged to reduce the current rate of biodiversity loss at global,
indigenous and original situations by 2010.