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Presentation on theme: "UNIT III: BIODIVERSITY & BIOTIC RESOURCES"— Presentation transcript:

Introduction Definition Genetic, Species and Ecosystem diversity Value of biodiversity Hot-spots of biodiversity Threats to biodiversity: habitat loss, poaching of wildlife, man-wildlife conflicts Endangered and endemic species of India Conservation of biodiversity: In-situ and Ex-situ conservation of biodiversity Food and Fodder resources

2 Introduction Biodiversity comprises the total range of plants, animals and other living things on the earth It is an index of a nation’s wealth and forms the basis of human survival and economic well being The term ‘biodiversity’ was coined by Walter Rosen (1986) Biodiversity has an intrinsic value and needs to be protected for its value to humans According to the biologist Edward Osborne Wilson, only 1.4 million different species of plants, animals and microorganisms were identified till now It is quite possible that nearly 10 to 100 million other species may be present undiscovered in many regions of the world that are unexplored (E.g. Rain forests)

3 Animals Plants Prokaryotes Protists Fungi
ORGANISMS Animals Plants Prokaryotes Protists Fungi Jellyfish, worms, arthropods, molluscs, echinoderms, amphibians, fish, reptiles, birds and mammals Seed bearing plants and non-seed bearing plants Bacteria and primitive algae Single-celled organisms Moulds, mushrooms and toadstools

4 Animals Invertebrates Vertebrates Fishes Amphibians Reptiles Birds
Protozoans, Poriferans Coelenterates Flatworms Annelids Arthropods Molluscans Echinoderms Vertebrates Fishes Amphibians Reptiles Birds Mammals

5 (c) Ecosystem diversity
Definition Biodiversity can be defined in many ways According to United Nations Environmental Program (UNEP) it is defined as “the totality of genes, species and ecosystems in a region” According to the World Resources Institute "Biodiversity is the variety of the world's organisms, including their genetic diversity and the assemblage they form The functional components of biodiversity include Genetic diversity Species diversity (c) Ecosystem diversity Genes are the components of species, and species are the components of ecosystems Therefore, alterations in the make-up of any level of this hierarchy can change the species and are central to the concept of biodiversity

6 (a) Genetic diversity Value of Genes
The variety of genes that exists within a single species is called genetic diversity. Examples include numerous breeds of dogs and cats These differences among the same species are due to the difference in their genes Species with good genetic diversity have more chances of survival in changing environment. E.g. Food crops like rice, wheat and corn On the other hand, species with low genetic diversity cannot adapt successfully to environmental changes and may become extinct Value of Genes Rice grown in Asia is protected from the four main rice diseases by genes brought in from a wild species from India The sugarcane industry in the US was saved from collapse by disease – resistant genes brought in from wild Asiatic species A tomato discovered in Andes has been used to increase the sugar content of cultivated varieties, increasing their commercial value

7 (b) Species diversity A species includes a group of interbreeding organisms of a natural population They generally share similar appearance, characteristics and genetics due to having relatively recent common ancestors The species is one of the basic units of biodiversity Species diversity is the variety and abundance of various species in a given habitat

8 (c) Ecosystem diversity
This refers to the variety of ecosystems that exist on our planet such as rivers, oceans, forests, deserts, mangroves grasslands etc. These ecosystems provide people with food and other useful products Ecosystems also show variations with respect to physical parameters like moisture, temperature, altitude, precipitation etc and create a microclimate This diversity has developed over millions of years of evolution If we destroy this diversity, it would disrupt the ecological balance We cannot even replace the diversity of one ecosystem by that of another

9 Biodiversity indices Alpha diversity refers to diversity within a particular area, community or ecosystem, and is measured by counting the number of taxa (distinct groups of animals) within the ecosystem (eg. families, genera, species) Beta diversity is species diversity between ecosystems; this involves comparing the number of taxa that are unique to each of the ecosystems Gamma diversity is a measure of the overall diversity for different ecosystems within a region. It refers to the total biodiversity over a large area or region

10 VALUE OF BIODIVERSITY Consumptive Value
The biodiversity products can be harvested and consumed directly by man E.g. fuel, food, drugs, fibre etc. Drugs and medicines: About 75% of the world's population depends upon plants or plant extracts for medicines The wonder drug Penicillin is derived from a fungus called “Penicillium” Recently Vinblastin and Vincristine, two anticancer drugs, have been obtained from Periwinkle (Catharanthus) plant, which possesses anticancer alkaloids A large number of marine animals are supposed to possess anti-cancer properties

11 Medicine Plant source Use
Table 2.1 Medicinal uses of some selected plant species Medicine Plant source Use Cochicine Autumn crocus Cancer prevention Digitalis Common foxglove Heart stimulant L-dopa Velvet bean Treatment of Parkinson’s disease Penicillin Penicillium fungus Antibiotic Quinine Yellow cinchona Antimalarial agent Resperine Indian snakeroot Lowering of blood pressure Taxol Pacific yew Anticancer agent Vinblastine Rosy periwinkle Bacitracin Bacterium Tetracycline Erythromycin Bee venom Bee Arthritis relief Morphine Poppy Analgesic

12 Poppy Plant Morphine from seeds

13 Foxgrove digitalis

14 Cinchona Plant Rauwolfia

15 Our forests are being used since ages for fuel wood
Fossil fuels like coal petroleum natural gas are also products of fossilized biodiversity.

16 (B) Productive Value Biodiversity provides us with many benefits and goods that have a price tag because of their commercial value These are the commercially usable values where the product is marketed and sold Animal products like tusks of elephants, musk from musk deer, silk from silk-worm, wool from sheep, fur of many animals, lac from lac insects etc, all of which are traded in the market

17 (C) Genetic Value Biological diversity is a valuable genetic resource
Most of the hybrid varieties of crops under cultivation have been developed by incorporating useful genes from different species of plants to produce better quality of the product with longer shelf-life or having better resistance to pests There are hundreds of examples which illustrate how genetic modification helped in improved quality of the products A few of them are mentioned as under • The genes from a wild variety of melon grown in U.P. helped in imparting resistance to powdery mildew in musk-melons grown in California

18 The genes from the Kans grass (Saccharum spontaneum) grown in Indonesia helped in imparting resistance to red rot disease of sugarcane A wild variety of rice from UP. saved millions of hectares of paddy crop from Grossy-Stunt virus

19 (D) Social Value Human cultures co-evolves with their environment, and the biological diversity can be important for cultural identity of a region Biological diversity is an integral part of many areas across the globe valued for tourism and recreational purposes These are the values associated with the social life, customs, religion and aspects of the people. Many of the plants are considered holy and sacred in our country like Tulsi (holy basil), Peepal, Mango, Lotus, Bael etc

20 Many animals like Cow, snake, Bull, Peacock, Owl etc have significant place in psycho-spiritual arena and thus hold social importance.

21 (E) Ethical Value It is also sometimes known as existence value. It involves ethical issues like "'all life must be preserved It is based on the concept of "Live and Let Live” If we want our human race to survive then we must protect all biodiversity, because biodiversity is valuable In many cultures, a particular species or landscape may be inseparably linked to a sense of identity and meaning. Some religious organizations call for the protection of nature simply because it is God’s creation. E.g. Ramasethu

22 (F) Aesthetic Value Natural and wild habitats harbors rich biodiversity and man gets much needed aesthetic pleasure by watching native plants and animals of a region Millions of people enjoy hunting, fishing, camping, hiking, wildlife watching and other nature based activities which forms the basis for ‘Ecotourism’. Wild life conservation programs including national parks, zoological and botanical gardens, snake, crocodile, butterfly parks Developing of new horticultural species and other novel species by biotechnology contribute to the existing aesthetic value of naturally occurring biodiversity

23 (G) Optional Value According to the biologist Edward Osborne Wilson, only 1.4 million different species of plants, animals and microorganisms were identified till now. It is quite possible that nearly 10 to 100 million other species may be present undiscovered in many regions of the world that are unexplored (E.g. Rain forests). Such unexplored biodiversity provides man with an option to find, realize and value its ecological services and other economical, social, aesthetic, ethical and medical uses for the benefit mankind However, this is possible only when conservation programs are taken up proactively. Otherwise, many plants, animals and microorganisms disappear before their discovery which is as good as 'book-burning’ that destroys former and future knowledge

24 Hotspots of Biodiversity
Hotspots are the main areas of focus for biodiversity conservation Extremely rich in biodiversity Have high level of endemism and are under constant threat of species extinctions and habitat destruction These hotspots covering less than 2% of the world's land area are found to have about 50% of the terrestrial biodiversity The term was introduced by Norman Myers (1988). Myers et al (2000) recognized 25 hot spots These are on a global level out of which two are present in India, namely the Eastern Himalayas and Western Ghats According to Myers et al. (2000) an area is designated as a hotspot when it contains at least 0.5% of the plant species as endemics


26 Global Hot spots 1. Tropical Andes 2. Mesoamerica 3. Caribbean
4. Brazil's Atlantic Forest 5. Choco/Darien/Western Ecuador 6. Brazil's Cerrado 7. Central Chile 8. California Floristic Province 9. Madagascar 10. Eastern Arc and Coastal Forests of Tanzania/Kenya 11. Western African Forests 12. Cape Floristic Province 13. Succulent Karoo 14. Mediterranean Basin 15. Caucasus 16. Sundaland 17. Wallacea 18. Phillipines 19. Indo-Burma 20. South-Central China 21. Western Gnats/Sri Lanka 22. SW Australia 23. New Caledonia 24. New Zealand 25. Polynesia/Micronesia

27 The 25 hotspots contain 44% of all vascular plant species and 35% of terrestrial vertebrates and encompass only 1.4% of the earths surface However, collectively they have lost 88% of their original primary vegetation Species in these areas are at risk from extinction if further habitat loss occurs It has been estimated that 50,000 endemic plants, which comprise 20% of global plant life, probably occur in only 18 ‘hotspots’ in the world Countries which have a relatively large proportion of these biodiversity hotspots are referred to as ‘Mega-diversity nations’

28 Hotspots in India Eastern Himalayas and Western ghats
These areas are particularly rich in floral wealth and endemism In addition to flowering plants some reptiles, amphibians , swallow tailed butterflies, and some mammals also exist Eastern Himalayas The area comprises Nepal, Bhutan, and neighboring states of northern India, along with a continuous sector of the Yunnan province in Southwest China All Himalayan forests lie north of the Tropic of Cancer, and some of them are at altitudes of m, they can be considered tropical forests Many deep and semi isolated valleys are exceptionally rich in endemic plant species In Sikkim, in an area of 7298 km2 , of the 4250 plant species , 2550 (60%) are endemic In Nepal, there are around 7000 plant species, many of which overlap with those of India, Bhutan, and even Yunnan. Of these species, at least 500 (8%) are believed to be endemic to Nepal Bhutan, possesses an estimated 5000 species, of which as many as 750 (15%) are considered to be endemic to the Eastern Himalayas

29 Western Ghats: Out of India’s plant species , 1600 endemics (40% of the total number of endemics) are found in an km2 along the sea side of the Western Ghats in Maharashtra, Karnataka, Tamil Nadu, Kerala Forest track up to 500 m in elevation, comprising 1/5th of the entire forest expanse, mostly evergreen while those in m range are semi- evergreen There are two main centers of diversity, the Agasthyamalai Hills and the Silent Valley/New Amambalam Reserve Basin The forest cover in western Ghats has reduced to 34 % from Floral and faunal commonality exists in India's two hot spots Although the two areas, the Eastern Himalayas and the Western Ghats are today disjunct and have their own characteristic flora and fauna, there are a number of species common to both

30 Threats to Biodiversity
‘Extinction’ is the elimination of a species which is a normal process of the nature All organisms die and are usually replaced by their own progeny as a part of evolution This rate of extinction is very slow and occurs naturally. For example, in undisturbed ecosystems, about one species is lost every decade On the other hand, anthropogenic impacts on populations and ecosystems have accelerated the rate of extinction and eliminated thousands of species Thus biodiversity is threatened by both nature and man in many ways (A) Natural Extinction Fossil records suggest that more than 99% of all species that existed in the past are now extinct Mass extinctions have wiped out vast numbers of species due to climate change For example, at the end of cretaceous period, large asteroids hit the earth and might have triggered climate changes Dinosaurs disappeared along with 50% of existing species

31 1.Population Risk 2.Environmental Risk
Random variations in population rates (i.e. birth rates and death rates) can cause a species in low abundance to become extinct It is a risk especially to species that consist of only a single population in one habitat For example—blue whales swim over the vast areas of ocean, and if in one year most whales were unsuccessful in finding a mate then births could be dangerously low 2.Environmental Risk These are variations in the physical or biological environment, including variations in predator, prey, symbiotic or competitor species In case of species that are sufficiently rare and isolated, such normal environmental variations can lead to their extinction 3.Natural Catastrophe: Natural catastrophes like fires, storms, floods, earthquakes, volcanic eruptions, changes in oceanic currents and upwelling, etc. cause the local extinction of most forms of life there

32 (B) Man induced Extinction
4.Genetic Risk Detrimental change in genetic characteristics in a small population of a species, due to reduced genetic variation genetic drift or mutation makes the species more vulnerable to extinction This is because it lacks the variety once present or because a mutation that leads to poor health becomes fixed in population (B) Man induced Extinction According to some ecologists, almost one million species are lost in a year which is equal to 27 species per day due to anthropogenic activities At this rate, millions of organisms will be eliminated in the next few decades which may trigger a mass extinction This may be not due to asteroids or volcanoes, but human impacts alone will be held responsible

33 (i) Habitat Loss A ‘habitat’ refers to a place where a specific species can be found From a habitat, an organism obtains food, water, sunlight, minerals, and other substances that are needed for its survival and reproduction The removal or destruction of such habitat where an organism lives is called ‘habitat loss’ It is difficult to estimate how many species become extinct each year because of habitat loss but it poses a serious threat to biodiversity The growth and expansion of human population has caused both quantitative and qualitative loss of the habitat Deforestation, construction of houses, roads, cities, bridges and dams for meeting the man’s demands have destroyed the habitat for many native species Habitat loss may be quantitative and qualitative E.g. Coringa mangroves decreased in the Kakinada bay ecosystem due to deforestation for aquaculture activities Oceans, lakes and rivers are damaged and destroyed by pollution

34 Habitat Fragmentation
It is a process where a large, continuous habitat is reduced in area and even divided into two or more fragments Habitat fragmentation may take place due to the development of roads, towers, canals, fields, industries, etc. in an original large habitat Diseases Pathogens, or disease organisms, may also be considered Predators The incidence of disease in wild species may increase due to human activities Pollution Environmental pollution is the most subtle form of habitat degradation The most common causes of which are pesticides, industrial effluents and emissions, and emission from automobiles Introduction of Exotic Species Organisms introduced into habitats where they are not native are termed as exotics They act as biological pollutants and are the most damaging agents of habitat alteration and degradation in the world

35 (ii) Wild life Poaching
The illegal killing/trading of animals and wildlife species is called ‘poaching’ that occurs across the globe Many animals are mercilessly and illegally killed for their meat, skins and internal organs and for sport One of the drivers for the illegal trade of animal parts is the multimillion dollar market that exists globally Illegal wildlife trade is one of the primary threats to a large number of species For instance, more than 90% of the world's wild rhinos have disappeared or killed for their magnificent horns The elephant populations in many nations declined to alarmingly low levels between 1979 and 1989, mainly due to the worldwide demand for ivory During this period, due to huge demand for ivory, poaching reduced Africa's elephant population to 50% In 1977, for instance, 1.3 million elephants lived in Africa while only 6,00,000 remained as of 1997 Savannah elephants were the worstly affected species because they sported largest tusks

36 Other species poached include
Tigers (Panthera tigris) for bones, rhinos for their horns, and bears for a variety of body parts All bear species, including Brown bear (Ursus arctos), Black bear (Ursus americanus), Polar bear (Ursus maritimus) Asiatic black bear (Ursus thibetanus), Spectacled bear (Tremarctos ornatus), Sloth bear (Melursus ursinus), Sun bear (Helarctos malayanus), Giant Panda bear (Ailuropoda melanoleuca) are used traditionally in China Polar Bear Poaching Polar bear (Ursusmaritimus) is among the largest carnivores in the world and is primarily a marine bear Numerous adaptations help them to lead life in icy habitats They have thick which covers even their feet, for warmth and traction on ice and can swim as far as 40 miles According to the ‘World Conservation Union’ (IUCN) estimates that there are between 20,000 and 25,000 polar bears in the world, distributed throughout the Arctic region The decreasing trends in well-studied populations are alarming

37 For example, in the western Hudson Bay, from 1,200 bears in 1987 the numbers decreased to 935 bears in 2004 In the Beaufort Sea north of Alaska, the population dropped 15 % in five years, from 1,800 to 1,526 bears It is feared that this population of bears may be declining due to illegal hunting, pollution, oil exploration, tourism and climate change Recognizing these alarming trends, Russia made polar-bear hunting illegal Canada, Denmark, Greenland, Norway, and the United States) entered into the International Agreement for the Conservation of Polar Bears in 1973

38 (iii) Man- Wildlife Conflicts
A major problem associated with the conservation of wild animals especially the herbivores like elephants in India is that of crop depredation and man-slaughter Animals such as elephants, wild boar and birds like peacock cause extensive damage to the crops This phenomenon has registered significant increase in recent years due to habitat fragmentation and degradation of natural forests and corridors Instances of man animal conflicts keep on coming to lime light from several states in our country In Sambalpur, Orissa 195 humans were killed in the last 5 years by elephants In retaliation the villagers killed 98 elephants and badly injured 30 elephants Several instances of killing of elephants in the border regions of Kote - Chamarajanagar belt in Mysore have been reported recently


The International Union of Conservation of Nature and Natural Resources (IUCN) maintains called a 'Red Database' at the World Conservation Monitoring Centre (WCMC) in which information on endangered and vulnerable species of plants and animals is kept From time to time, this database is translated into popular form and published as 'Red Data Books‘ The red data symbolizes the warning signal for those species which are endangered and if not protected are likely to become extinct in near future

41 In India, nearly 450 plant species have been identified in the categories of endangered, threatened or rare Existence of about 150 mammals and 150 species of birds is estimated to be threatened while an unknown number of species of insects are endangered A species is said to be endangered when its number has been reduced to a critical level or whose habitats, have been drastically reduced and if such a species is not protected and conserved, it is in immediate danger of extinction It may not be of direct relevance here to give a complete list of endangered flora and fauna of our country However, a few species of endangered reptiles, birds, mammals and plants are given below: (a) Reptiles: Gharial, green sea turtle, tortoise, python (b) Birds: Great Indian bustard, Peacock, Pelican, Great Indian Hornbill, Siberian White Crane (c) Carnivorous: Indian wolf, red fox, Sloth bear, red panda, Mammals tiger, leopard, striped hyena, Indian lion, golden cat, desert cat, dugong (d) Primates: Hoolock gibbon, lion-tailed macaque, Nilgiri langur, Capped monkey, golden monkey (e) Plants: A large number of plant species like Rhododendrons, Rauwolfia serpentina, the sandal wood tree Santalum, Cycas beddomei etc

42 Gharial

43 Peacock Pelican

44 Indian Tiger Leopard

45 Indian Lion Red Fox

46 Great Indian Bustard

47 Siberian White Crane

48 Capped Monkey Golden Monkey

49 Rhododendron

50 Rauwolfia serpentina, Cycas beddomei

51 (ii) Vulnerable Species
(i) Endangered Species A species is said to be endangered when its number has been reduced to a critical level or whose habitats, have been drastically reduced and if such a species is not protected and conserved, it is in immediate danger of extinction. (ii) Vulnerable Species The species that are under threat such that they may have to be classified as endangered in the near future if causal factors continue to operate Species whose populations have been seriously depleted Species whose populations are still abundant but are under threat throughout their range (iii) Rare Species These are species with small population size in the world usually localized within restricted habitats It is necessary to mention here that a species that is rare is not necessarily in danger of becoming extinct ; some species, like the Whooping Crane, are naturally rare (iv) Threatened Species The term 'threatened' is used in the context of conservation of the species which are in any one of the above three categories These are species that have declined significantly in total numbers and may be on the verge of extinction in certain localities

52 India contains globally important populations of some of Asia's rarest animals, such as the Bengal Fox, Asiatic Cheetah, Marbled Cat, Asiatic Lion, Indian Elephant, Asiatic Wild Ass, Indian Rhinoceros, Markhor, Gaur, Wild Asiatic Water Buffalo etc. According to IUCN, India contains 172 species of animals that are considered globally threatened. In other words, 2.9% of the world's total number of threatened species occurs in India The impact of man-related actions could result in the loss of such valuable species Group IUCN Red List Threat Category Endangered Vulnerable Rare Indeterminate Insufficiently known Mammals Birds Reptiles Amphibians Fishes Invertebrates 13 6 1 20 3 2 25 4 12 5 Total 26 49 45 28

53 Endemic Species of India
Endemics are species that are found in a single locality/area and nowhere else in the world. They, thus have a value in their uniqueness The endemism of Indian biodiversity is quite high About 33% of the country's flora are endemic to the country and are concentrated mainly in the North-East, Western Ghats, North-West Himalaya and the Andaman and Nicobar Islands Out of about 47,000 species of animals in our country 7000 are endemic

Conservation is defined as '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 needs and aspirations of future generations' Given the value and importance of biodiversity, there is a great need to conserve the ever threatened organisms. Some of the international agencies play a crucial role in evolving the conservation strategies CGIAR -Consultative Group for International of Agricultural Research CIFOR -Centre for Institute of Forest Research UNCED -UN Convention of Environmental Development WWF -World Wide Fund for nature UNEP - United Nations Environmental Protection CITES -Convention on International Trade in Endangered Species of wild Fauna and Flora In addition to the developed nations, efforts by G-15 countries have significantly helped in promoting the implementation of conservation strategies in these nations

There are two approaches of biodiversity conservation: In situ conservation (within habitat): This is achieved by protection of wild flora and fauna in nature itself Ex situ conservation (outside habitats) This is done by establishment of gene banks, seed banks, zoos, botanical gardens, culture collections etc. Insitu conservation applies only to wild fauna and flora and not to the domesticated animals and plants, because conservation is achieved by protection of populations in nature E.g., National Parks, Sanctuaries, Biosphere reserves etc.

56 Ex- situ Conservation This type of conservation is mainly done for conservation of crop varieties, the wild relatives of crops and all the local varieties with the main objective of conserving the total genetic variability of the crop species for future crop improvement or afforestation programs In India, we have the following important gene bank/seed bank facilities: (i) National Bureau of Plant Genetic Resources (NBPGR) is located in New Delhi. Here agricultural and horticultural crops and their wild relatives are preserved by cryo-preservation of seeds, pollen etc. by using liquid nitrogen at a temperature as low as -196 °C Varieties of rice, pearl millet, Brassica, turnip, radish, tomato, onion, carrot, chilli, tobacco, poppy etc. have been preserved successfully in liquid nitrogen for several years without losing seed viability

57 National Bureau of Animal Genetic Resources (NBAGR) located at Karnal, Haryana. It preserves the semen of domesticated bovine animals (iii) National Facility for Plant Tissue Culture Repository (NFPTCR) for the development of a facility of conservation of varieties of crop plants/trees by tissue culture. This facility has been created within the NBPGR

58 Seed Bank

59 Endangered animal species are preserved using similar techniques
The genetic information needed in the future to reproduce endangered animal species can be preserved in gene banks, which consist of cryogenic facilities used to store living sperm, eggs, or embryos The Zoological Society of San Diego has established a "frozen zoo" to store such samples from more than 355 species, including mammals, reptiles, and birds

60 Maintenance of Repositories
Since facilities are available for conservation of valuable germplasm, it is necessary that other resources and facilities for multiplication, regeneration, evaluation, characterization, documentation and distribution of this germplasm are also made available However, the identity and genetic stability must be ensured during conservation and management of germplasm Samples must be maintained in duplicates at different sites If these precautions are not taken and adequate facilities for management of collections are not extended, some of the germplasm repositories may become germplasm mortuaries In other words, the germplasm collections would become absolutely useless

61 Summary Biodiversity is of extreme importance for ensuring ecological balance It has Consumptive, Productive, Genetic, Ethical, Social, Aesthetic and Optional values There are 10 biogeographic zones and 26 provinces India is a megadiversity nation Hot spots are regions with rich biodivesity and there are 25 hot spots in world while India has 2 hot spots Many species are threatened by both nature and man India has 2% of global endangered and endemic species Biodiversity can be conserved by in-situ and ex-situ methods


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