Unit 2 (part 3)- biodiversity

Biodiversity and its Conservation

INTRODUCTION
 Biodiversity is the degree of variation of life
forms within a given ecosystem, biome, or an
entire planet.
 Biodiversity is the variety of the world’s
organisms, including their genetic diversity and
the assemblage
 Biodiversity is a measure of the health of
ecosystems.

INTRODUCTION
 Genes are component of species & species are
component of ecosystem. Therefore, altering the
make-up of any level of this can change the other
species are the concept of this.
 Biodiversity is in part a function of climate. In
terrestrial habitats, tropical regions are typically
rich whereas polar regions support fewer species

(1) Genetic Diversity:
It’s a concept of the variability within species, as measured
by the variation in genes within a particular species,
variety, subspecies, or breed.
Ex: all rice varieties belong to species Oryza sativa, but
thousand of wild & cultivated varieties of rice which show
variation at genetic level & differ in their colour, size,
shape & aroma, nutrient content. This is genetic diversity
of rice.
 Importance:
Various applications of biotechnology such as crop &
animal breed, improvement, depend upon the
identification of genetic material for incorporating
desirable traits.

(2) Species Diversity:
Richness of species in an ecosystem is called
species diversity.
Species diversity means variety of living organisms
on earth.

(3) Ecosystem diversity:
It shows variations in ecological niches, trophic
structure, food webs, nutrient cycling & also in
physical parameters such as moisture,
temperature, precipitation etc.
Ex: grasslands, wetlands, rivers fresh water etc.
Ecosystem diversity assessment may include
estimation of richness in particular groups &
evolution of their relative abundance.

Values of biodiversity:
It is classifies into two:
[1]Direct value: direct in agriculture, medicine &
industry.
These can be estimated by observing the activities
of representative group of people, by monitoring
collection point for normal products & by
examining export/import statistics.
It is also classified into two:

(i) Consumptive use value:
This value is assigned where the biodiversity
product can be harvested & consumed directly.
Ex: fuel, food, drug etc.
(ii) Productive Use value:
These are commercially usable values where the
product is marketed & sold in commercial markets.
Ex: silk from silk worm, wool from sheep etc.

[II] Indirect values:
These benefits ecosystem services, such as air &
water purification, climate regulation & generation
of moisture & oxygen.
Ex: small animals like earthworms, insects,
millipeds help to give soil its texture & fertility and
are crucial for aeration.
Rainforest tree in 100 years of lifespan can transfer
2.5 million gallons of water from soil to air. So,
their roles are crucial in hydrological cycle.
- It can be classifies into following:

(i) Non-consumptive/use value:
It involves benefits such as soil
protection/formation, climate regulation, air
purification, medical research etc.
(ii) Asthetic value: Natural & wild landscapes
are aesthetically & provide opportunities to get
away from human dominated landscapes.
Ex: Wild life conservation, national parks,
zoological & botanical gardens etc.

(iii) Social & cultural values:
They are associated with social life, customs,
religion & psycho-spiritual aspects of life.
Ex: Tulsi, Lotus, Bael, Cow, Bull, Owl etc.
(iv) Ethical value:
It involves moral justification for conservation of
biodiversity. These values are based on the belief
that all species have a moral right to exist,
independent of our need for them.
Ex: Boycott of furs, animal skins etc.
(v) Option Value:
Value is the value of knowing that there are
biological resources existing on existing, that may
one day prove to be an effective option for

BIO-GEOGRAPHICAL CLASSIFICATION OF
INDIA
 Bio-geographic classification of India was done by
Rodgers and Panwar (1988), describing 10 bio-
geographic zones in India, further divided into 25
biogeographic provinces.
 The classification was done using various factors
such as altitude, moisture, topography, rainfall,
etc. Biogeographic zones were used as a basis for
planning wildlife protected areas in India.

BIO-GEOGRAPHICAL CLASSIFICATION OF
INDIA
 From the stand point of biodiversity, India is given the
status of a “Mega-diversity” zone. There are 10 bio-
geographic zones witch are distinguished clearly in
India. They are as follows—
a) Trans Himalayan zone.
b) Himalayan zone.
c) Desert zone.
d) Semiarid zone.
e) Western ghat zone.
f) Deccan plateau zone.
g) Gangetic plain zone.
h) Coast
i) North east zone.
j) Islands present near the shore line.

Unit 2 (part 3)- biodiversity

THE COUNTRY HAS 10 DIFFERENT BIO GEOGRAPHIC
ZONES AND 26 BIOTIC PROVINCES:
Bio geographic Zones Biotic provinces
Trans-Himalayas Ladakh mountains, Tibetan plateau
Himalayas Northwest, west, central and east Himalayas
Desert Thar, Kutch
Semi-arid Punjab plains, Gujarat Rajputana
Western Ghats Malabar plains, Western Ghats
Deccan Peninsula Central highlands, Chotta-Nagpur, Central
Plateau, Deccan South
Gangetic Plains Upper and Lower Gangetic plains
Coast West and East coast, Lakshadweep
North-East Brahmaputra valley, Northeast hills
Islands Andaman and Nicobar

1. TRANS-HIMALAYAN REGION
 The Himalayan ranges immediately north of the Great
Himalayan range are called the Trans- Himalayas.
.

 The Trans-Himalayan region with its sparse
vegetation has the richest wild sheep and goat
community in the world.
 The snow leopard is found here, as is the
migratory black-necked cranes.

2. HIMALAYAS
 The Himalayas consist of the youngest and
loftiest mountain chains in the world.

 The forests are very dense with extensive growth
of grass and evergreen tall trees. Oak, chestnut,
conifer, ash, pine, deodar are abundant in
Himalayas. There is no vegetation above the
snowline.
 Several animals live in the Himalayan ranges.
Chief species include monal, wild sheep,
mountain goats, ibex, shrew, and tapir. Panda
and snow leopard are also found here.

3. SEMI-ARID AREAS
 Adjoining the desert are the semi-arid areas, a
transitional zone between the desert and the
denser forests of the Western Ghats.

 The natural vegetation is thorn forest. This region
is characterized by discontinuous vegetation cover
with open areas of bare soil and soil-water deficit
throughout the year.
 A few species of xerophytic herbs and some
ephemeral herbs are found in this semi-arid tract.
 Asiatic lions, Birds, jackals, leopards, eagles,
snakes, fox, buffaloes are found in this region.

4. WESTERN GHATS
 The mountains along the west coast of peninsular
India are the Western Ghats, which constitute
one of the unique biological regions of the world.
 The Western Ghats extend from the southern tip
of the peninsula (8°N) northwards about 1600 km
to the mouth of the river Tapti (21°N).
 The mountains rise to average altitudes between
900 and 1500 m above sea level.

 Apart from biological diversity, the region boasts of high
levels of cultural diversity, as many indigenous people
inhabit its forests.
 The Western Ghats are amongst the 25 biodiversity hot-
spots recognized globally. These hills are known for their
high levels of endemism expressed at both higher and
lower taxonomic levels. Most of the Western Ghat endemic
plants are associated with evergreen forests.
 Rice cultivation in the fertile valley proceeded gardens of
early commercial crops like areca nut and pepper.
 The Western Ghats are well-known for harboring 14
endemic species of caecilians (i.e., legless amphibians) out
of 15 recorded from the region so far.

5. NORTH-WEST DESERT REGIONS
 This region consists of parts of Rajasthan, Kutch,
Delhi and parts of Gujarat.
 The climate is characterized by very hot and dry
summer and cold winter. Rainfall is less than 70
cms.

 The plants are mostly xerophytes. Babul, Kikar,
wild palm grows in areas of moderate rainfall.
 Indian Bustard, a highly endangered bird is found
here. Camels, wild asses, foxes, and snakes are
found in hot and arid deserts.

6. DECCAN PLATEAU
 Beyond the Ghats is Deccan Plateau, a semi-arid
region lying in the rain shadow of the Western
Ghats. This is the largest unit of the Peninsular
Plateau of India.

 The highlands of the plateau are covered with
different types of forests, which provide a large
variety of forest products.
 Fauna like tiger, sloth bear, wild boar, gaur,
sambar and chital are found throughout the zone
along with small relict populations of wild
buffaloes, elephants and barasingha.

7. GANGETIC PLAIN
 In the North is the Gangetic plain extending up
to the Himalayan foothills. This is the largest
unit of the Great Plain of India.
 The Great Plains cover about 72.4mha area with
the Ganga and the Brahmaputra forming the
main drainage axes in the major portion.

 The physiographic scenery varies greatly from arid
and semi-arid landscapes of the Rajasthan Plains to
the humid and per-humid landscapes of the Delta
and Assam valley in the east.
 The plain supports some of the highest population
densities depending upon purely agro-based economy
in some of these areas. The trees belonging to these
forests are teak, sal, shisham, mahua, khair etc.

8. NORTH-EAST INDIA
 North-east India is one of the richest flora
regions in the country.
 It has several species of orchids, bamboos, ferns
and other plants.
 Here the wild relatives of cultivated plants such
as banana, mango, citrus and pepper can be
found.

9. ISLANDS
 The two groups of islands, i.e., the Arabian Sea
islands and Bay Islands differ significantly in
origin and physical characteristics.
 The Arabian Sea Islands (Laccadive, Minicoy,
etc.) are the foundered remnants of the old land
mass and subsequent coral formations. On the
other hand, the Bay Islands lay only about 220
kms.

 Away from the nearest point on the main land
mass and extend about 590 kms. With a
maximum width of 58 kms the island forests of
Lakshadweep in the Bay of Bengal have some of
the best-preserved evergreen forests of India.
 Some of the islands are fringed with coral reefs.
Many of them are covered with thick forests and
some are highly dissected.

10. COASTS
o India has a coastline extending over 5,500 kms. The west
coast is narrow except around the Gulf of Canbary and the
Gulf of Kutch.
o In the extreme south, however, it is somewhat wider along
the south Sahyadri. The backwaters are the
characteristic features of this coast.

o Extensive deltas of the Mahanadi, Godavari, Krishna
and Kaveri are the characteristic features of east
coast. Mangrove vegetation is characteristic of
estuarine tracts along the coast for instance, at
Ratnagiri in Maharashtra.
o Larger parts of the coastal plains are covered by
fertile soils on which different crops are grown. Rice
is the main crop of these areas. Coconut trees grow all
along the coast.

HOT SPOTS OF BIODIVERSITY
 Areas which exhibit high species richness as well
as high species endemism is called as hot spots of
biodiversity.
 There are 35 such hot spots on a global level and
only two of which are in India, namely Eastern
Himalayas and Western Ghats.
 These hot spots cover less than 2% of the world
land area and have about 50% of terrestrial
biodiversity.
 Two hot spots in India are:
(i) Indo-Burma region covering Himalayas
(ii) Western-Ghats-Srilanka region

THREATS TO BIODIVERSITY
 Elimination of species is a natural process is
known as species extinction.
 Human actions causes extinction of biodiversity
as follows:
(i) Loss of Habitat
(ii) Poaching
(iii) Man-Wildlife Conflicts

(I) HABITAT LOSS & DEGRADATION
(i) Pollution: various human activities like
industries, automobiles etc. pollutes water &
air bodies. Ex: population of fish eating birds
are greatly decline due to DDT deposition in the
fish which was sprayed in water to kill
mosquitoes.
(ii) Introduction of exotic species: A species
entering in new geographical area is called
exotic species. Main cause is accidental
transport, agriculture etc. ex: Nile Perch an
exotic predatory fish introduced in lake Victoria
has threatened the entire ecosystem by
eliminating small fishes.

(iii) Disease: Polluted water & soil may act as
disease causing & killing agent for biodiversity.
(iv) Over-exploitation: Growing rural poverty,
increasingly efficient methods of harvesting &
globalization of the economy combine to exploit
species to the point of extinction.
(v) Shifting: Some rural people destroy biological
communities & hunt endangered species because
they are poor & have no land of their own.

(vi) Natural calamities
(vii) Global warming & acid rain:
Affects climate, ecology, agriculture, aquatic &
terrestrial ecosystem.

[II] POACHING
It is the illegal trade of wildlife products by killing
prohibited endangered animals.
Animals are killed for skin, meat & internal organs
as well as for sport & accidental killing.
Measures for prevention:
1.Ban on illegal trade.
2. Prepare a database of wildlife related crimes.
3. Establish trans-boundary control posts.
4. Develop collaborative partnerships with all
commercial logging & transport companies.

[III] MAN WILDLIFE CONFLICT
 This occurred due to expansion of human
populations towards the natural habitats of
wildlife.
 Animals may move out of forest to search of food.
 Generally ill, weak & injured animals have a
tendency to attack man.
 Some of the incidents are:
 In Orissa 195 humans were killed in last 5 years
by elephants. Thus villagers killed98 elephants.

Prevention:
1. Adequate crop compensation & cattle
compensation scheme must be started.
2. Cropping pattern should be changed near forest
borders. And adequate fodder should be
available for animals in forests.
3. Wild life corridors should be provided for mass
migration of big animals.

CONSERVATION OF BIODIVERSITY
The management of human use of the biosphere so
that it may yield the greatest sustainable benefit to
present generation while maintaining its potential
to meet the need & aspirations of future
generations.

OBJECTIVES
 To maintain essential ecological processes & life
supporting systems.
 To preserve the diversity of species.
 To ensure sustainable utilization of species &
ecosystem which support milllions of rural
communities as well as major industries.

[I] In Situ Conservation:
It deals with conservation of living resources
through their maintenance within the natural
ecosystem in which they occur.
This is done using biosphere reserves, national
parks and wildlife sanctuaries.
(i) National parks: Its an area strictly reserved
to the betterment of the wildlife & their activities
such as forestry, grazing or cultivation are not
permitted, and no private ownership is allowed.

(ii) Sanctuary:
It is generally species oriented.
Operations such as harvesting of timber, forest
products & private ownerships are permitted as
long as they don’t interfere with well being of
animals.
(iii) Biosphere Reserves:
It is undisturbed natural areas for scientific study
as well as areas where any sort of disturbance is
under control.
They have been set for ecological research &
habitat preservations.

The zones of biosphere reserve:
a) Core zone: No human activity is allowed in this zone. Comprises of legally
protected ecosystem.
b) Buffer zone
Limited human activity is permitted in the buffer zone.
c) Manipulation zone or Transition zone
Several human activities can occur in the manipulation zone.
Example: Settlements, cropping, forestry, recreation etc.

Characteristics:
1. Contain abundant genetic diversity
2. Biosphere should be unique.
3. Should have sufficient energy resources.
4. Have legal protection.

ROLE OF BIOSPHERE RESERVES
A biosphere reserve preserves
a) wild population
b) life style of tribal
c) genetic resources of domesticated plants and
animals.
It helps in
1) Conservation
2) promotes economic development
3) Scientific research, monitoring and education.

EX-SITU CONSERVATION
Conservation out side the habitats.
(i) Zoos:
It’s the place where animals are kept for public
showing.
(ii) Botanical gardens:
Important role in conservation of plant species.
Record of plants that are in cultivation have been
kept in GREEN BOOKS (acc. To botanical survey
of India)
Has a special role in active research & action
oriented plan for conservation.

(iii) Seed Banks:
Seeds have to be stored under minimal life so that
they can be kept for several years without
accumulations of mutations & with minimum loss
of viability
It can be done with cold storage.
(iv) Pollen storage:
For conservation of genetic diversity.

(v) Tissue culture:
Best method for preservation of genes through
tissue banks.
Low maintenance cost.
Protection of genotypes from natural calamities &
diseases.

ADVANTAGES OF EX-SITU CONSERVATION
 Organisms is assured of food, shelter & security
& hence can have longer life span & breeding.
 Chances of survival are enhanced.
 Also provides the possibility of using genetic
techniques to improves the concerned species.

DISADVANTAGES
 Employed to selective species because of
limitation of space, finance & facilities.
 New life forms can not be evolve & gene pools get
stagnant.

Unit 2 (part 3)- biodiversity

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