2. • The convention on Biological diversity defines biodiversity as : “ the
variability among living organism from all sources including, inter alia,
terrestrial, marine and other aquatic ecosystems and the ecological
complexes of which they are a part; this includes diversity within species,
between species, and of ecosystems.”
• Thus, Biodiversity refers to the variety of forms it also includes the genes,
they contain and the ecosystem they form.
• It deals essentially with dynamic processes and increases when new genetic
variation is produced and decreases on the loss of genetic variation or
species extinction.
3. TYPES OF BIODIVERSITY
GENETIC DIVERSITY
• It refers to variation of genes within species. This variation can exist between
different populations of the same species as well as between individuals within a
population.
• Genetic diversity provides organisms and ecosystems with capacity to recuperate
after change has occurred.
• Thus Genetic diversity is a level of biodiversity that refers to the total number of
genetic characteristics in the genetic makeup of a species. It is distinguished form
genetic variability, which describes the tendency of genetic characteristics to vary.
• Genetic diversity plays a great role in the adaptability and survival of a species. A
species that has a large degree of genetic diversity among its individuals will have
more variations form which to choose the most fitting allele.
4. SPECIES DIVERSITY
• Species diversity is a measure of the diversity within an ecological community that
incorporates both species richness (the number of species in a community) and the
evenness of species’ abundance.
• Species diversity can be measured in term of
1.Species richness- refers to the number of various species in a defined area.
2.Species abundance- refers to the relative numbers among species. For example, the
number of species of plants, animals and microorganism may be more in an area than
that recorded in another area.
3.Taxonomic or phylogenetic diversity- refers to the genetic relationships between differ
groups of species.
• Species diversity is not evenly distributed across the globe. The overall richness of species is
concentrated in equatorial regions and tends to decrease as one moves from equatorial to
polar regions.
• In addition, biodiversity in land ecosystems generally decreases with increasing altitudes.
The other factors that influence biodiversity are amount of rainfall and nutrient level in soil.
In marine ecosystems, species richness tends to be much higher in continental shelves.
5. Ecosystem Diversity
• It refers to the presence of different types of ecosystems.
• According toWhittaker (1965), the community diversities are of three types:
1. α- Diversity: it tells the species diversity in a given community. It depends
upon species richness and evenness.
2.β- Diversity: it describes a range of communities due to replacement of
species which arises due to the presence of different microhabitats, niches
and environmental conditions.
3. γ- Diversity: it describes diversity of habitat over a total land escape or
geographical area.
6. THREATS OF BIODIVERSITY
• Biodiversity is considered as a reservoir of resources to be used for the manufacture of food,
medicine, industrial products, etc.
• But with an increased demand of rapid population growth, biodiversity is gradually depleting. A
number of plants” and animal species have already become extinct and many are endangered.
• The different factors responsible for causing threat to biodiversity are as follows:
1. Habitat destruction
2. Habitat fragmentation
3. Pollution
4. Over exploitation
5. Introduction of exotic species
6. Diseases
7 Shifting or Jhum cultivation
8. Poaching of wild life
7. BIODIVERSITY CONSERVATION
• Biodiversity is being depleted by the loss of habitat, fragmentation of
habitat, over exploitation of resources, human sponsored ecosystems,
climatic changes, pollution invasive exotic spices, diseases, shifting
cultivation, poaching of wild life etc.
• Conservation of biodiversity, thus becomes pertinent.
• The conservation of biodiversity has three basic objectives:
1.To maintain essential ecological processes and life supporting systems.
2.To preserve the diversity of species.
3.To make sustainable utilization of species and ecosystem.
8. In Situ Conservation
• The conservation of species in their natural habitat or natural ecosystem is known
as in situ conservation.
• In the process, the natural surrounding or ecosystem is protected and maintained
so that all the constituent species (known or unknown) are conserved and
benefited.
• The factors which are detrimental to the existence of species concerned are
eliminated by suitable mechanism.
• The different advantages of in situ conservation are as follows:
1.If is a cheap and convenient way of conserving biological diversity.
2.It offers a way to preserve a large number of organism simultaneously, known
or unknown to us.
3.The existence in natural ecosystem provides opportunity to the living
organisms to adjust to differed environmental conditions and to evolve in to a
better life form.
9. • The only disadvantage of in situ conservation is that it requires large space
of earth which is often difficult because of growing demand for space.
• The protection and management of biodiversity through in situ
conservation involve certain specific areas known as protected areas which
include national parks, sanctuaries and biosphere reserves, reserved forests,
protected forests and nature reserves.
10. SACRED GROVES
• In many cultures, tracts of forest were set aside, and all the trees and
wildlife within were venerated and given total protection.
• Such sacred groves are found in Khasi and Jaintia Hills in Meghalayam,
Aravalli hills of Rajasthan, Western Ghat regions of Karnataka and
Maharashtra and the Sarguja, Chanda and Bastar areas of Madhya Pradesh.
• In Meghalaya, the sacred groves are the last refuges for a large number of
rare and threatened plants.
11. BIODIVERSITY HOTSPOTS
• On a global basis, the problem has been addressed by eminent conservationists.
• They identified for maximum protection certain ‘biodiversity hotspots’ regions with
very high levels of species richness and high degree of endemism (that is , species
confined to that region and not found anywhere else).
• Initially 25 biodiversity hotspots were identified but subsequently nine more have
been added to the list, bringing the total number of biodiversity hotspots in the
world to 34.
• There hotspots are also regions of accelerated habitat loss.
• Three of these hotspots – Western Ghats and Sri Lanka, Indo-Burma and Himalaya
– cover our country’s exceptionally high biodiversity regions.
• Although all the biodiversity hotspots put together cover less than 2 percent of the
earth’s land area, the number of species they collectively harbor is extremely high
and strict protection of these hotspots could reduce the ongoing mass extinctions
by almost 30 percent.
12. Ex-situ conservation
• Ex-suit conservation involves maintenance and breeding of endangered plants and animals
under partially or wholly controlled conditions in specific area like zoo, gardens, nurseries
etc.
• That is, the conservation of selected plants and animals in selected areas outside their
natural habitat is known as ex-situ conservation.
• The stresses on living organism due to competition for food, water, space etc. can be
avoided by ex-suit conservation there by providing conditions necessary for a secure life
and breeding.
• Some important areas under these conservation are
1.Seed gene bank
2.Field gene bank
3.Botanical gardens
4.Zoos
13. Which one of the following is not a site for in-suit method of conservation
of flora?
1. Biosphere reserve
2. Botanical garden
3. National park
4. Wildlife sanctuary
15. • India is a recognized as one of the mega-diverse countries, rich in biodiversity and
associated traditional knowledge.
• The term mega diverse country refers to any one of a group of nations that horbor
the majority of earth’s species and high number of endemic species.
• Conservation international identified 17 mega diverse countries countries in 1998.
• Many of them are located in , or partially in , tropical or subtropical regions.
• With just 2.4% of the land area, India accounts for nearly 7% of the recorded
species even while supporting almost 18% of human population.
• In term of species richness, India ranks seventh in mammals, ninth in birds and fifth
in reptiles.
• In term of endemism of vertebrate groups, India's position is tenth in birds with 69
species , fifth in reptiles with 156 species and seventh in amphibians with 110
species.
16. India Represents
• Two ‘Realms’
• Five Biomes
• Tem Bio-geographic Zones
• Twenty five Bio-geographic provinces
17. REALMS
• Biogeographic realms are large spatial regions within which ecosystems
share a broadly similar biota.
• Realm in a continent or sub-continent sized area with unifying features of
geography and fauna & flora.
• In world eight terrestrial biogeographic realms are typically recognized.
• The Indian region is composed of two realms.
The Himalayan region represented by Palearctic Realm
The rest of the sub-continent represents by Malayan Realm
18. BIOMES
• The term biomes means the main groups of plants and animals living in
areas of certain climate patterns.
• It includes the way in which animals, vegetation and soil interact together.
The plants and animals of that area have adapted to that environment.
• The five biomes of India are
Tropical Humid Forests
Tropical Dry or Deciduous Forests (Including Monsoon Forests)
Warm deserts and semi-deserts
Coniferous forests and Alpine meadows.
19. BIOGEOGRAPHIC ZONES
• Biogeographic classification of India is the division of India according to biogeographic charactertics.
• Biogeography is the study of the distribution of species, organism, and ecosystems in geographic space and
through geological time.
• There are ten biogeographic zones in India.
1.Trans Himalayan zone
2.Himalayan zone
3.Desert zone
4.Semiarid zone
5.Western Ghat zone
6.Deccan Plateau zone
7.Gangetic Plain zone
8.North east zone
9.Coastal zone
10.Islands present near the shore line
20. BIODIVERSITY HOTSPOTS
• Hot spots are the richest and most threatened reservoirs of plant and animal
life of the earth.
• The concept was given in 1988 by Norman Myers.
• In India, Western Ghats and Eastern Himalayas (Includes some parts of Indo-
Burma or Purvanchal Hills) are two hot spots of India.
21. • To qualify as a biodiversity hotspot, a region must meet two strict criteria
• Must have at least 1,500 species of vascular plants as endemics (>0.5% of
world’s total)
• Has to have lost at least 70% of its primary vegetation habitat
• Accordingly, 34 biodiversity hotspots have been so far identified.
• Collectively, the biodiversity hotspots support 60% of world’s plant and
animal species with a high share of endemics and cover around 2.5% of
earth’s land surface.
22. HOTTEST HOT SPOTS
• Some hot spots are much riches than others in term of their numbers of endemics.
• Five key factors have been taken into consideration and those biodiversity hot spot
that tops the list with respect to these five factors are considered as hottest hot
spots.
• Factors
Endemic plants,
Endemic vertebrates,
Endemic plants/area ration (Species per 100km2),
Endemic vertebrates/ area ratio (Species per 100 km2) and
Remaining primary vegetation as % of original extent.
23. • The eight hottest hot spots in term of the above five factors are
1.Madagascar
2.Philippines
3.Sundaland (South east asia)
4.Brazil’s Atlantic Forest
5.Caribbean
6.Indo-Burma
7.Western Ghats and Sri Lanka
8.Eastern Arc and Coastal Forests ofTanzania/ Kenya
