CAPF-AC (Assistant Commandant) Exam Study Material : Geography - Biodiversity and its conservation

India is an identified mega diverse country, rich in biodiversity and associated traditional knowledge. The country also has a tradition of conservation and sustainable use of its biodiversity, which has now come under pressure on account of various factors including development imperatives, habitat fragmentation, and introduction of invasive alien species.

Biodiversity comprises all the diversity observed among species, their populations and also the vast ecosystems.

In other words Biological diversity, or biodiversity, encompasses the variety of all life on earth. Biodiversity manifests itself at three levels: species diversity which refers to the numbers and kinds of loving organisms; genetic diversity which refers to genetic variation within species; and ecosystem diversity which denotes the variety of habitats. To date, about 1.7 million species have been described while many more await discovery. India, a megadiversity country with only 2.4 per cent of the land area, accounts for 7-8 per cen of the recorded species of the world spread over 45,500 species of plants and 91,000 species of animals that have been documented so far.

In terms of species richness, India ranks seventh in mammals, ninth in birds and fifth in reptiles. In terms of endemism of vertebrate groups, India’s position in tenth in birds with 69 species, fifth in reptiles with 156 species and seventh in amphibians with 110 species. India’s share of crops in 44 per cent as compared to the world average of 11 per cent. India also has 23.39 per cent of its geographical area under forest and tree cover.

Of the 34 gloablly identified biodiversity hotspots, India harbours four hotspots, i.e., Himalaya, Indo- Burma, Western Ghats and Sri Lanka and Sundaland.

I. Faunal diversity

So far, nearly 91,212 faunal species (7.43 per cent of the world’s faunal species) have been recorded in the country. Whereas inventories of mammals, birds, reptiles, amphibians and fishes are fairly complete, a large number of other life forms are yet to be described.

The Indian faunal groups show diverse range of dndemismacross groups. Some of the lower groups such as Mesozoa (100 per cent), Acanthocephala (88.6 per cent), Oligochaeta (77.8 per cent), Platyhelminthes (71.9 per cent), Kinorhyncha (70 per cent) show high degree of endemism. among higher groups, Amphibia (61.2 per cent) and Reptilia (47 per cent) deserve special mention.

As per the IUCn Red List (2008). India has 413 globally threatened faunal species, which is approximately 4.9 per cent of the world's total number of threatened faunal species. The global estimates as per IUCN Red List, 2008 suggest that 10 per cent (5,966 species) of vertebrate and 0.20 per cent (2,496 species) of invertebrate described fauna is threatened. In 2004 one species, megaptera novaeangliae, showed an upward trend of population while eleven species shows stable populations. Further, of the total 447 threatened species, for which trends are available, 218 are showing decreasing trend of population as per the 2004 status. The 2008 report, however, indicates upward population trend of one-homed rhinoceros in the country, as a result, the threat category has improved from endangered to vulnerable.

India, through its strong initiatives for survery and monitoring of biodiversity, is contributing towards new discoveries. For example, ZSI has discovered 655 faunal species in 2007 and National Bureau of Fish Genetic Resources (NBFGR) reported 36 new fin fish species from diverse biogeographic zones of India.

II. Floral Divesity

In terms of plant diversity, India ranks tenth in the world and fourth in Asia.With over 45,500 plant species, India represents nearly 11 per cent of the world’s known floral diversity. As elsewhere in the world, many organisms fungil algae, lichens and bryophytes are yet to be described and remote geographica areas are to be comprehensively explored.

Angiospersms: India has about 17,527 species of flowering plants (more than 7 per cent of the world’s known flowering plants) in 247 families and 2984 genera. The dominant families with more than 500 species are Poaceae-1291; Orchidaceae-1229; Leguminosae-1225; Asteraceae-892; Rubiaceae- 616; Cyperaceae-545; Euphoribaceae-527; and Acanthaceae-510.

Gymnosperms nare represented by about 67 species. Pinaceae (6 genera and 15 species) is the largest famialy, followed by Cupressaceae (13 genera and 13 species), Ephedraceae (1 genus, 7 species) and Gnetaceae (1 genus and 5 species). The species of Gnetum and Cycas are mostly confined to North Eastern region, Eastern and Western Ghats, and Andaman & Nicobar Islands.

Pteriodphytes: India has about 1200 species under 204 genera. While species of Marsilea, Azolla and Salvinia grow in aquatic habitats, those of Acrostichum occur in mangrove eco-systems. The north-eastern region (including Eastern Himalaya) is rich in pteridophyic diversity with about 845 species, followed by south India (including Eastern and Western Ghats) with 345 species and north India (including Western Himalaya) with 340 species. About 17 per cent of the species are endemic of India. The families such as Polypodiaceae (137 species), Dryopteridaceae (125 species), Athyriaceae (97 species), Thelypteridaceae (83 species), Salaginella (62 species), Asplenium (45 species) and Polystichum (45 species) are som of the dominant families and genera of the pteriodophytic flora of India region.

Bryophytes represented by 2500 species are the second largest-group of green plants in India distributed largely in Eastern Himalaya, Northeastern India, Western Himalaya and the Western Ghats. Mosses constitute the major component of Indian bryoflora with 1576 species followed by liverworts and hornworts (924 species). Lejeuneaceae (155 species) is the largest family followed by Pottiaceae (129), Dicranacea (119), bryaceae (98) and Sematophyllaceae (92 species). Fissidens (67 species) is the largs genus followed by Plagiochila (65) and Frullania (63). Nineteen genera and 629 species are endemic to India.

Major Multilateral environment agreements (MEAs) ratified by India

Lichens representing symbiotic association of fungi and algae, constitute a dominant component of epiphytic and saxicolous vegetation, and comprise 2,223 species in 283 genera and 72 families. Western Ghata are the rivhes region with 800 species (38 per cent) followed by Eastern Himalaya with 759 species (37 per cent) and Western Himalaya with 550 species (27 per cent). Families such as Parmeliaceae, Graphidaceae, Physciaceae, Usneaceae, Cladoniaceae, and genera like Parmelia, Graphina, Usnea, Graphis and Lecannora are among the dominant families and genera of Indian lichens. about 23 per cent species, mainly belonging to genera Graphina, Trypethelium, Graphis and Porina, are endemic to India. Andaman & Nicobar Islands (24 per cent), Western Ghats (20 per cent) and Eastern Himalaya (18 per cent) show high percentage of endemic species.

Fungi: India has 14;500 species of fungi in 2,300 genera and 250 families with maximum diversity in the Western Ghats followed by the eastern Himalaya and the western Himalaya. Deuteromycetes with 900 genera and 6000 species (40 per cent) is the largest group of Indiamycoflora, followed by Ascomycetes [680 genera / 3500 species (25 per cent)] and Basidiomyceter [520 genera / 3400 species (23 per cent)]. Cercospora with 707 species is the largest genus of Indian fungi followed by Puccinia (328 species) and Phyllosticta (280 species). About species are endemic to the country.

Algae are represented by over 7,175 species in 666 genera. They are found in a variety of habitats ranging from aquatic (both fresh water and marine) to terrestrial. Cholorophyceae with 4,495 species is the largest family followed by Cyanophyceae (1,453 species) and Bacillariophyceae (516 species).

Eighteen families of flowering plants occuring in India such as Ancistrocladaceae, Biebersteiniaceae, Martyniaceae, Tetra-centraceae and Trichopodaceae, etc., are monogeneric. About 2,863 (16.4 per cent) are trees, which include some of the highly valued timber species of the world. Indi is also a storehouse of primitive flowering plants, confined mainly in North Eastern region of the country. Diversity of such plants led Takhtajan (1969) to designate this region as the “Cradle of Flowering Plants’. The Indian flora also shows a rich diversity in aquatic flowering plants. Some important families of aquatic plants include Hydrocharitaceae (13 species),Pontederiaceae (13 species), Alismateacea (8 species), Aponogetonaceae (6 species), Potamogetonaceae (6 species), Typhaceae (4 species), Salviniaceae (3 species), etc. The insectivorous plant families, yet another group of unique plants are represented by Lentibulariaceae (36 species), Droseraceae (3 species), and Nepenthaceae (1 species).

About 11,058 species are endemic to India region, 6,200 of which belong to flowring plants alone. Eastern Himalaya and north-eastern region (about 2,500 species), peninsular India including western and Eastern Ghats (about 2,600 species), northwestern Himalaya (about 800 species) and Andaman & Nicobar Islands (about 250 species) are the areas rich in endemic plants.

As in the case of fauna, new plant species are continually being discovered in the country. For example, 41 plant taxa were discovered by BSI and other researchers from diverse bio-geographic zones of Idnia during 2007. Similarly in cryptogams (Lichens and Bryophytes), the National Botanical Research Institute (NBRI), Lucknow described 11 new species during 2007-08. Under the AICOPTAX, 493 taxa new to science have been discovered

III. Crop genetic diversity

India stands seventh in the world in terms of contribution of species to agriculture and animal husbandry. In qualitative terms too, the contribution has been significant. The National Bureau of Soil Survey and Land Use Planning distinguished 20 broad agro ecological zones, based on natural features and crop growing periods. India has over 800 crop species and 320 wild relatives: millets (51); legumes (31); fruits (109); spices and condiments (27); vegetables (54); fiber crops (24); oil seeds, tea, coffee, tobacco and sugarcane (12); and medicinal plants (3,000). The National Gene Bank at NBPGR is primarily responsible for conservation of unique accessions on long-term basis, as base collections for posterity, predominantly in the form of seeds.

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