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Biodiversity 4 unit Biodiversity Biodiversity refers to the variety and variability among all groups of living organisms and the ecological complexes of which they are a part Units of Biodiversity 1)Genetic diversity 2)Species diversity 3)Ecosystem diversity Genetic diversity • Genes are the basic units of hereditary information transmitted from one generation to other • The genes found in organisms can form enormous number of combinations each of which gives rise to some variability • When the genes within the same species show different versions due to new combinations, it is called genetic variability • For eg, all rice varieties belong to the species Oryza Sativa, but there are different varieties which differ in their shape, size, aroma due to variations at the genetic level Species diversity • This is the variability found within the population of a species • The richness of species in an ecosystem is called species diversity • The total number of living species is in the range of 10-50 million. But till now only about 1.5 million species have been actually described and given scientific names Ecosystem diversity • An ecosystem develops its own characteristic community of living organisms depending upon the availability of abiotic resources, environmental conditions and other factors • For eg, a pond possess different sets of flora and fauna as compared to the river ecosystem • This diversity has developed over millions of years of evolution and is of great value that must be kept intact Biogeographical classification of India • India has different types of climate and topography in different parts of the country and these variations have induces enormous variability in flora and fauna • India has a rich heritage of biological diversity and occupies the tenth position among the plant rich nations of the world • Based on the biodiversity, climate, topography India has been classified into 10 biogeographic zones India’s biographic zones S.No Biographic Zone Biotic Province 1 Trans –Himalayan Upper regions 2 Himalayan North-west Himalayas, West Himalayas, Central Himalayas, East Himalayas 3 Desert Kutch, Thar, Ladakh 4 Semi-arid Central India, Gujarat-Rajwara 5 Western Ghats Malabar Coast, Western Ghat mountains 6 Deccan Peninsula Deccan plateau south, Central plateau, Eastern plateau, Chotta Nagpur, Central highlands 7 Gangetic plain Upper gangetic plain, Lower gangetic plain 8 North-East India Brahmaputra valley, North-Easter hills 9 Islands Andaman islands, Nicobar islands, Lakshadweep islands 10 Coasts West coast, East coast Biogeographical classification of India Value of biodiversity The multiple uses of biodiversity value has been classified by McNeely et al in as follows: 1) Consumptive use value 2) Productive use value 3) Social value 4) Ethical value 5) Aesthetic value 6) Optional values 7) Ecosystem service value Consumptive use value These are direct use values where the biodiversity product can be harvested and consumed directly e.g. fuel, food, drugs ,fibre etc Food: A large number of plants are consumed by human beings as food. About 90% of present day crops have been domesticated from wild tropical plants. Drugs and medicines: 75% of the world’s population depends upon plants or plant extracts for medicines Penicillin-Penicillium Quinine-Bark of cinchona Vinblastin and Vincristine-Catharanthus Fuel: Forests have been used since ages for fuel wood. Fossil fuels are also products of fossilized biodiversity Productive use values • These are commercially usable values where the product is marketed and sold • It may be lumber, wild gene resources • Animal products like tusks of elephants, musk from musk deer, wool from sheep • Despite international ban on trade in products from endangered species, smuggled hide, fur, tusks worth millions of dollars are being sold Social value • Values associated with the social life, customs, religion and psycho-spiritual aspects of people • Many of the plants are considered holy and sacred in our country (Tulsi, Peepal, Mango) • Many animals like cow, snake, bull, peacock also have significant place in our psychospiritual arena and thus hold special social importance Ethical value • Ethical values is also sometimes known as existence value. • It involves ethical issues like “all life must be preserved” and the concept of “Live and let live” • The ethical value means we may or may not use a species, but we feel the existence of the species is necessary Aesthetic value • Great aesthetic value is attached to biodiversity • Stretches of barren lands with no signs of visible life is not a pleasant sight • Eco-tourism is based on the aesthetic value of biodiversity • Ecotourism is estimated to generate about 12 billion dollars of revenue annually Optional values • These include the potentials of biodiversity that are presently unknown and need to be explored • For eg, there is a possibility that we may have potential cure for AIDS or cancer existing within the depths of marine ecosystem, or tropical ecosystem Ecosystem service value It refers to the services provided by ecosystem like 1) 2) 3) 4) 5) 6) Prevention of soil erosion Prevention of floods Maintenance of soil fertility Cycling of nutrients and water Fixation of nitrogen Role as carbon sinks Different categories of biodiversity value clearly indicate that ecosystem, species and genetic diversity have enormous potential and a decline in biodiversity will lead to huge economic, ecological and socio-cultural losses India as a mega-diversity nation • India is one of the 12 mega diversity countries in the world • The ministry of Environment and Forests, records show 47,000 plant species and 89,000 animal species • A large proportion of the India Biodiversity is still unexplored • Due to diverse climatic conditions there is a complete rainbow spectrum of biodiversity in our country Distribution of species in India Group-wise species distribution Plants Bacteria Number 850 Animals Number Lower groups 9979 Mollusca 5042 Fungi 23,000 Algae 2500 Arthropoda Bryophytes 2564 Fishes 2546 Pteridophytes 1022 Amphibia 428 Gymnosperms 64 Reptiles 1228 Angiosperms 15,000 Birds 204 Mammals 372 57,525 Reasons for India as a mega-diversity nation 1)Endemism • Species which are restricted only to a particular area are know as endemic. • India shows a good number of endemic species. About 62% amphibians 50% lizards 53% fresh water fishes 36%reptiles 10%mammals and 33% flowering plants are endemic to India. • Western ghats are the site of maximum endemism Reasons for India as a mega-diversity nation 2)Centre of origin • A large number of species are know to have originated in India • Nearly 500 species of flowering plants have their origin in India • India has been the center or origin for 166 species of crop plants and 320 species of wild relatives of cultivated crops Reasons for India as a mega-diversity nation 3)Marine diversity • The coastline of our country exhibits a rich biodiversity • Along 7500 km long coastline, in the mangroves, coral reefs back waters etc, different species are found • The marine diversity is rich in mollusks, crustaceans and several species of mangrove plants and sea grasses are found Biodiversity at global national and local level Global biodiversity : Globally we have roughly identified 1,70,000 flowering plants 30,000 vertebrates 2,50,000 other groups of species Terrestrial biodiversity : Tropical rainforests,savannas,desert,tundra etc. Tropical rainforests • These are the earths largest storehouse of biodiversity. • About 50 to 75% of global biodiversity lies in these tropical rain forests. • Of about 3000 plants identified by national cancer research 70% is derived only from tropical rain forests • Extracts from one of the creeping vines in the rain forests at cameroon have proved effective in the inhibitioin of replication of AIDS virus Temperate forests Globally they have nearly • 1,70,000 flowering plants • 30,000 vertebrates • 2,50,000 other groups of species. Marine diversity Marine diversity is even much higher than terrestrial biodiversity but it is still less known and described Biodiversity at national level • India is the second largest nation containing 5% of world’s biodiversity and 2% of the earths surface Hotspots of biodiversity • Areas which exhibit high species richness as well as high species endemism are termed as hotspots of biodiversity • To qualify as a biodiversity, a region must meet two strict criteria: 1)It must contain at least 0.5% or 1,500 species of plants as endemics, 2)It has to have lost at least 70% of its primary vegetation Global hotspots of biodiversity 1)Tropical Andes 2)Mesoamerican forests 3)Caribbean 4)Brazil’s Atlantic forest 5)Western Ecuador 6)Brazil’s Cerrado 7)Central Chile 8)California Floristic Province 9)Madagascar 10)Eastern Arc and coastal forest of Tanzania/Kenya 11)Western African Forests 12)Cape Floristic Province 13)Succulent Karoo 14)Mediterranean Basin 15)Caucasus 16)Sundaland 17)Wallacea 18)Philippines 19) Eastern Himalayas 20)South-central China 21)Western-Ghats Sri Lanka 22)South-western Australia 23)New Caledonia 24)New Zealand 25)Polynesia/Micronesia Salient features of Indian Hotspots A)Eastern Himalayas: • The eastern himalayan region encompasses Bhutan, North east India, and south, central and eastern Nepal • The region is home to 163 globally threatened species including Asia’s Three largest herbivores –the Asian elephant, the greater one horned rhinoceros, and the wild water buffalo Carnivore-The tiger Birds-Vultures, Storks and hornbills • Out of the world’s recorded flora, 30%are endemic to India of which 35,000 are in the Himalayas Salient features of Indian Hotspots B)Western Ghats • It extends along a 17000 sq.km strip of forests in Maharashtra, Karnataka, TN and Kerala and has 40% of total endemic plants • The major centers of diversity are Agastyamalai Hills and Silent valley-the New Amambalam reserve basin • It is reported that only 6.8% of original forests are existing today while the rest has been deforested or degraded Threats to Biodiversity • Extinction or elimination of a species is a natural process of evolution. • The process of extinction has become particularly fast in the recent years of human civilization • One of the estimates puts the figure of extinction as 27/day • If the present trend continues we would lose 1/3rd to 2/3rd of our current biodiversity by the middle of 21st century Loss of Habitat • Destruction and loss of natural habitat is the single largest cause of biodiversity loss • Billions of hectares of forests and grasslands have been cleared over the past 10,000 years for conversion into agricultural lands, pastures, settlement areas or development projects • Thousand of species have perished due to loss of their natural habitat • A phenomenon known as habitat fragmentation have resulted in loss on many singing birds • As a result of human intervention marine biodiversity is under serious threat due to large scale destruction of the fragile breeding and feeding grounds Poaching • Illegal trade of wildlife products by killing prohibited animals, is a threat to wildlife • Despite international ban on trade in products from endangered species, smuggling of wildlife items like furs, hides, tusks, etc continues • The worse issue is that for every live animal that gets into market, about 50 additional animals are caught and killed Man-wildlife conflicts • When wild life causes immense damage and danger to man , the conflict occurs • In retaliation, the villagers electrocute or kill the animals which sometimes exceed poaching Causes: 1) Dwindling of habitats and human encroachments into the forest areas 2) The wild life corridors through which animals used to migrate seasonally have been used for human settlements and hence animals attack the settlements Causes of man-animal conflict 3) The stopping of cultivation of paddy, sugarcane etc.. within the sanctuaries have led the animals to stray out 4) The compensation paid by the government in lieu of the damage caused to the crops is not adequate and the agonised farmer gets revengeful and kills the wild animals 5) Ususally the ill, weak and injured animals have a tendency to attack man Classification of species Extinct species- A species is said to be extinct when it is not seen in the wild for 50 years at a stretch. Eg Dodo, passanger pigeon Endangered species-When the number has been reduced to a critical level or whose habitats have been drastically reduced and when not protected and conserved they are endangered species Rare species-Species which are not endangered at present, but are at risk are categorised as rare species Endemic species-Species which are restricted to a particular area is called as endemic species Endangered species • These are species which if not protected are likely to become extinct in near future • The International Union for Conservation of Nature and Natural Resources(IUCN) publishes the Red Data Book which includes the list of endangered species of plants and animals • In India nearly 450 plant species , 150 mammals and 150 species of birds have been listed as endangered species Few endangered species of India 1) Reptiles :Green sea turtle, Tortoise, Python 2) Birds: Peacock, Great Indian Hornbill, Pelican, Siberian White Crane 3) Carnivorous mammals: Indian wolf, red fox, tiger, lion, red panda, leopard, striped hyena, desert cat, dugong 4) Primates: Capped monkey, golden monkey, nilgiri langur, hoolock gibbon 5) Plants:species of orchids, rhododendrons Santalum, Cycas beddonei etc Endemic species of India • India has two biodiversity hotspots and thus possesses a large number of endemic species Endemic flora-Sapria himalayana, Uvaria lurida, Nepenthes Khasiana, Pedicularis perroter etc Endemic animals-Varanus, reticulated python, Indian Salamander, Viviparous toad, nectophhryne Red fox Indian wolf Capped langur Hoolook gibbon Nilgiri langur Desert cat Dugong Red panda Golden langur Rhododendron Cycas beddomei Green sea turtle Hornbill orchids pelican salamander varanus Nectophryne Conservation of biodiversity • The enormous value of biodiversity due to their genetic, commercial medical, aesthetic importance emphasize the need to conserve biodiversity. • There are two approaches of biodiversity conservation – In situ conservation – Ex situ conservation In Situ conservation • This is achieved by protection of wild flora and fauna in nature itself.eg Biosphere reserves, National parks, Sancturies, Reserve forests etc • The Biosphere reserves conserve some representative ecosystems as a whole for long term in situ conservation. Gulf of mannar, Nilgiri, Sunderbans, Nanda devi are few biosphere reserves • A National park is an area dedicated for the conservation of wildlife along with its environment. • Each park aims at conservation of some particular species of wildlife along with others Important national parks in India Name of the national park Important wildlife Kaziranga One horned Rhino Gir national park Indian Lion Dachigam Hangul Bandipur Elephant Periyar Elephant, Tiger Kanha Tiger Corbett Tiger Dudwa Tiger Ranthambore Tiger Sariska Tiger Wild life sanctuaries • These are protected areas where killing, hunting, shooting or capturing of wildlife is prohibited except under control of highest authority Name of Sanctuary Major wild life Ghana Bird Sanctuary 300 species of birds Hazaribagh Sanctuary Tiger, Leopard Sultanpur Bird Sanctuary Migratory birds Nal Sarovar Bird Sanctuary Water birds Abohar wildlife Sanctuary Black buck Mudumalai wildlife Sanctuary Tiger, elephant, Leopard Vedanthangal Bird Sanctuary Water Birds Jaldapara Wildlife Sanctuary Rhinoceros, elephant, Tiger Wild Ass Sanctuary Wild ass, Wolf, nilgai, chinkara 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 • In this the conservation in captivity under human care • The objective is to conserve the total genetic variability of the crop species for future crop improvement or afforestation programmes Important gene bank/seed banks 1) National Bureau of Plant Genetic Resources (NBPGR)-Located in New Delhi Here agricultural and horticultural crops are cryo preserved 2) National Bureau of Animal Genetic Resources(NBAGR)-Located in Haryana Preserves semens of domesticated bovine animals 3) National Facility for Plant Tissue Culture Repository (NFPTCR)-within NBPGR Conservation of crop plants/trees by tissue culture Project Tiger • Project Tiger Scheme has been under implementation since 1973 as a Centrally Sponsored Scheme of Government of India • The main objective of Project Tiger is to ensure a viable population of tiger in India for scientific , economic , aesthetic , cultural and ecological values and to preserve for all time, areas of biological importance as a natural heritage for the benefit, education and enjoyment of the people • Main objectives under the scheme include wildlife management, protection measures and site specific eco development to reduce the dependency of local communities on tiger reserve resources Project Tiger • Initially, the Project started with 9 tiger reserves, covering an area of 16,339 sq.km., with a population of 268 tigers. At present there are 27 tiger reserves covering an area of 37761 sq.km., with a population of 1498 tigers • Project Tiger has put the tiger on an assured course of recovery from the brink of extinction, and has resurrected the floral and faunal genetic diversity in some of our unique and endangered wilderness ecosystem. Project Elephant • Project Elephant (PE), a centrally sponsored scheme, was launched in February 1992 to provide financial and technical support to major elephant bearing States in the country for protection of elephants, their habitats and corridors • The Project Elephant in India also aimed to decrease the human-elephant battles and help in the welfare of domesticated elephants in India • Aims: 1) Ecologically restoring the natural habitats and migratory routes of the elephants 2) Resolution of the increasing conflicts between man and elephants in important habitats and moderating the pressures of human and domestic stock activities in important elephant habitats Various aims of Project Elephant 4) Developing scientific and planned management measures for conservation of elephants and controlling the population of wild Asiatic elephants, which are almost on the verge of extinction. 5) Protecting the elephants from poachers and other unnatural causes of death and illegal ivory trade is also one of the major concerns of the Elephant Project in India 6) Researching on issues related to elephants and creating public awareness and education programs for it 7) Eco-development and Veterinary care for the elephants 8) Project Elephant also aims at maintaining health care and breeding of tame elephants Current status of Project Elephant • The project elephant has still not led to as much increase in the number of elephants as it was expected • Wildlife conservationists state that the progress has been real slow and people in charge of the project are themselves not very clear of the causes of decline in the number of elephants • Project Elephant tries to ensure a free movement for the elephants and thus conserve large areas for them that are called ‘elephant reserve range’