This document provides an introduction to biodiversity and discusses it at multiple levels - genetic, species, ecosystem, and landscape. It defines biodiversity as the variety of living organisms, including diversity within and between species. Genetic diversity refers to variation within species and between populations, and is important for plant and animal breeding. Species diversity is the number of species within an area or ecosystem. Ecosystem diversity looks at the variety of habitats and biological communities within a region. The document examines these concepts and provides examples like genetic diversity in maize and major ecosystem types around the world.

1. WELCOME…

2. INTRODUCTION
 The term Biological diversity also abbreviated as biodiversity introduced by the Walter G Rosen in 1985.
It is defined as the variety and variability among the living organisms and the ecological complexes in
which they occurs.
 It includes the diversity of the living organisms and their ecosystem. Biodiversity is the sum of the genes,
species, varieties, populations of the different ecosystems.
 Biodiversity also refers to organisms found within the living world i.e. the number, variety and variability
of living organisms.
 Diversity within species is referred to as genetic diversity.
 Diversity between species is referred to as species diversity and diversity at habitat level is referred to as
ecosystem or ecological diversity

3. The totality of genes, species and ecosystems in a region. Biodiversity can be studied
at four different levels:
1. Genes
2. Species
3. Ecosystems
4. Landscapes

4. GENETIC DIVERSITY (STUDY AT GENE LEVEL)
 The Genetic variation in the organisms is due to the recombination in the genetic material of the
organisms during the sexual reproduction. Each organism has their own genetic makeup and characters.
 The genetic diversity refers to variation of genes within species this includes distinct population of the
same species or genetic variation within population.
 The term Gene Pool is used to indicate the Genetic diversity of the different species.
 The Gene pools of the wild and cultivated plants are very important for the development of the new
varieties through the Natural selection methods or the artificial hybridization methods.
 The genetic variability of the plants especially economically important plants is very important for the
healthy breeding populations to develop and evolution of the new characters in the plants.
 If the Genetic variability is reduced amongst the plants it leads to the inbreeding and leads to the
extinction of the species.

5. GENETIC DIVERSITY IN MAIZE

6. SPECIES DIVERSITY (STUDY OF VARIETIES OF SPECIES IN NATURE)
 Species diversity refers to biodiversity at the most basic level.
Species is defined as the group of similar organisms which
interbreeds with one another and produces the offspring.
 Species is the basic unit of the classification. It includes all the
species on Earth. Species diversity includes diversity of the
species of the plants, animals and microorganism.
 In plants it includes diversity of the Algae, bryophytes,
Pteridophytes, Gymnosperms and Angiosperms. It is the
number of different species that are represented in a given
community.

7. DIVERSITY I DICES BASED ON SPECIES
 Numerous indices and methods are available for measurement of diversity. Ecologists have estimated
biodiversity by three measures:
 (i) Species richness : which is indicated by the total number of species in an area (Ashton, 1992)
 (ii) Species abundance: which is indicated by the total number of individuals of a species in an area
 (iii) Species evenness: which represents equitability of species as given by their relative abundance.

8. PLANT DIVERSITY AT THE ECOSYSTEM LEVEL (ECOSYSTEM
DIVERSITY) -
 The term Ecosystem was proposed by A. G. Tansley in 1935, Ecosystem is the collection of the living or
biotic components like plants, animals and microorganisms and the abiotic components like climatic,
edaphic factors.
 The richness of the biosphere is due to the ecosystem diversity. The Natural Vegetation is consist of
Terrestrial, Aquatic, and other Ecosystems.
 The Terrestrial Ecosystem is Forest, Grassland and Desert Ecosystem while Aquatic Ecosystem is Fresh
water and Marine water Ecosystem. The Artificial Ecosystem is Cropland Ecosystem.
 Kinds of the Ecosystem:
Ecosystem can be Natural or Atificial. Temporary or Permanent. Large or small.

9. 1.NATURAL ECOSYSTEM
(a) Terrestrial Ecosystem: Forest, Grasslands, Deserts etc.
In forest ecosystem heterogonous vegetation is present with the diversity in the mosses, Lichen,
Ferns, flowering plants with the different habits like Herbs, Shrubs, Trees, Climber etc. The Desert ecosystem
is the Ecosystem with the less rainfall and high temperature during theday and cold nights.
(b) Aquatic Ecosystem: These Ecosystems further differentiated into
(i) Fresh Water Ecosystems: These Ecosystems may be Lotic (Running water such as River, streams,
springs, and Lentic (Standing water such as Lake, Pond, Pool, Puddle, Swamp etc.
(ii) Marine Water Ecosystem: These includes salt water bodies with deep bodies(Ocean) or shallow bodies
(Sea or Estuary).

10. 2. ARTIFICIAL ECOSYSTEM-
 These Ecosystems are called as Manmade or Man Engineered Ecosystem. E.g. CroplandEcosystem.
 Ecosystem diversity addresses the combined characteristics of biotic properties (biodiversity) and abiotic
properties (geodiversity).
 Ecological diversity can also take into account the variation in the complexity of a biological community,
including the number of different niches, the number of trophic levels and other ecological processes.
 The wide variety in physical features and climate situations have resulted in a diversity of ecological
habitats like forests, grasslands, wetlands, coastal, marine ecosystems and desert ecosystems, which
harbour and sustain the immense biodiversity.

11. MEASUREMENT OF THE DIVERSITY-
 The measure of the biodiversity of the species also known as species richness. Whittaker (1972) describes
three terms to measure biodiversity over spatial scales: The various ways by which we can measure the
biodiversity are:
 1. Alpha Diversity: Diversity within the particular area or Ecosystem and expressed by the number of
species (Species richness) in that ecosystem. Combination of species richness and evenness is used to
represent the diversity within community or habitat.
 2. Beta Diversity: It is a comparison of diversity between Ecosystems usually measured as amount of
species change between the Ecosystems. Species frequently change when habitat or community
changes. The intercommunity or differentiation in diversity expressing the rate of species turn over per
unit change in habitat can be assessed by the variety of indices.
 3. Gamma Diversity: Measure of the overall biodiversity for the different ecosystems within the region.
It study the diversity of the habitats over the total geographical area.

12. MAJOR ECOSYSTEM TYPES OF THE WORLD
 (1) Tropical Moist Forests: These are found between the Tropic of Cancer and the Tropic of Capricorn.
In the Asian continent, they are found on the southern slopes of the Eastern Himalayas, in south-west
India (Western Ghats), Sri Lanka, Malaysia, Indonesia, Philippines, Thailand and New Guinea. Tropical
moist forests cover only 6 to 7% of the Earth's surface.
 (ii) Temperate Forests: Temperate forests occur mainly in the Northern Hemisphere. Temperate forests
are dominated by deciduous hardwood trees and to a lesser extent by evergreen broad leaf hardwood
trees and conifers.
 (iii) Arid and Semiarid Ecosystems: The biological diversity in these ecosystems is rather poor and is
influenced by water availability. These ecosystems comprise drought evading, enduring and resisting
taxa.

13. (iv) Boreal Forests: These are circumpolar biomes in North America and Eurasia. Boreal
forests are generally poor in terms of species richness, but the functional diversity of
component species is very high.
(v) Arctic and Alpine ecosystems:These are cold-dominated ecosystems lacking trees.
They occupy about 8% of the terrestrial surface of the Earth with 5% in the arctic region
and 3% in the alpine. These ecosystems support only about 4% of the Earth's flora, with
1500 species in the arctic zone and 10,000 in the alpine regions.
(vi) Grasslands: Grasslands often form natural vegetation on the land surface of the Earth.
The grassland ecosystem is dominated by grass and grass like species, although in some
areas shrubby and Herbaceous elements.
(vii) Agroecosystems: Agroecosystems are those in which man has deliberately selected
specific crop plants to replace the natural vegetation. Therefore, it is an artificial
ecosystem. Agroecosystems include shifting cultivation, home and kitchen gardens,
pastures, mixed farming, multiple cropping horticulture, alley farming, cereal and pulse
cropping, orchards and plantations Agroecosystems also have weeds, escapes, parasitic
microbes/pests and soil organisms.

14. (vii) Wetland Ecosystems: Wetlands are areas of marsh, swamp, peat land or water, whether natural
or artificial, permanent or temporary.
• Freshwater Wetlands: Aselmann and Crutzen (1989) recognized the following categories of
freshwater wetlands.
• Bogs: These can be defined as peat producing wetlands of moist climatic regions. Organic matter
accumulates over long periods without decomposing due to lack of or slow activity of microbes.
• Fens: These are wetlands producing peat; fens are influenced by soil nutrients flowing through the
system. Fens are more prolific than bogs in terms of supporting vegetation.
• Swamps: These are forested wetlands on waterlogged or inundated soils. However, there is no
accumulation of peat here. Tree representatives are dominant in swamps. The very characteristic
swamps of India occur in the Western Ghats with species of Myristica are predominant.
• Marshes: These are usually herbaceous 'swamps' or 'mires'. Grasses, sedges, reeds and foxtails
usually dominate the vegetation. Marshes may be seasonal orpermanent.
• Flood-plains: These are wetlands periodically flooded with water occurring alongside rivers or
lakes. They vary considerably in vegetation.
• Lakes: Lakes are open water bodies varying in depth from a few centimeters toseveral meters.
• Marine Ecosystems: Biodiversity of the marine environment is very poorly known. Marine
ecosystem occupies 71% of earth's surface.

15. SCOPE OF THE PLANT DIVERSITY-
 1. Plant diversity is the backbone for agriculture, aquaculture, animal husbandry forestry and a host of other
applied branches of biology. Hence it stands at the very foundation of development.
 2. To sustain ever growing population high yielding grains and pulses are need to be developed. Fresh water
supplies are depleting day by day and also the soil quality is deteriorating throughout the world. Hence, new
varieties of useful plants and new breeds of domesticated animals have to be evolved for increased
yield/productivity desired lifetime, disease resistance etc.
 3. Globalization has resulted to developmental activities and these are at the cost of pronounced
deforestation.
 4. Biodiversity is fast becoming the fundamental requirement on which the new industrial developments and
innovations are going to be based.
 5. Biodiversity will become the only purposeful scientific tool with which one can bridge the social and cultural
world.
 6. It offers new sources of food, medicine, fodder, fuel etc.
 7. Biodiversity is the pillar of human development.

16. THANK YOU…!