Biodiversity and its conservation

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Biodiversity and its conservation Article in Yojana · August 2010

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ENVIRONMENT FOCUS

Biodiversity and its Conservation Arvind Singh

B

There are three levels of biodiversity

or ecosystem the species diversity is very essential. In a community the survival of all species are interrelated to the existence of other living organisms. Ecosystem diversity refers to variations in the

namely genetic diversity, species

biological communities in which

diversity and ecosystem diversity.

species live, the ecosystem in which

Genetic diversity is the genetic

communities exist and interactions

variation within species, both among geographically separated populations and among individuals within single population. This genetic diversity is the result of different modes of adaptation in different habitats, which provides organisms and ecosystems with capacity to recuperate after change has occurred. Species diversity

among

denotes the variety of species on

more than 25 per cent of all

earth from acellular viruses to single

medicines available today are derived

celled microorganisms like bacteria,

from tropical plants. Plants are

mycoplasmas, actinomycetes etc. to

important source of grazing for cattle

multicellular plants and animals. For

and

proper

animals is an important source of

iodiversity or Biological

diversity refers to the variety and variability among genes, species and ecosystems.

conservation of biodiversity is the need of the hour for food, fodder, fuel, timber and medicinal requirements and also for the agricultural production, ecological balance, and mitigation of environmental pollution

functioning

community

of

particular

these

levels.

Ecosystem

diversity is reflected in diverse biogeographic zones such as lakes, deserts, coasts, estuaries etc.

Significance of biodiversity Biodiversity plays a crucial role in the life of man. Biodiversity fulfils the need of food, fodder, fuel, timber and medicines. It is estimated that

other

herbivores.

Flesh

of

food for human beings.

The author is an Ecologist associated with Department of Botany, Banaras Hindu University, Varanasi.

YOJANA August 2010

57

Biodiversity helps in increasing

Biodiversity helps in elimination

Ecologically diverse forest ecosystems are home of wild-life

the agricultural production and also

of

in

Breakdown of the pollutants and

and tribals. The forest of surrounding

its absorption is a feature of many plants. The plant Vinca rosea (Sadabahaar) has the ability to degrade Trinitrotoluene (TNT) like explosive. Several strains of microorganisms have been found useful for the purpose of cleaning up toxic wastes. Some plant species thrive on soils that are rich in heavy metals. Several plants have the ability to hyperaccumulate metals like copper, nickel, cadmium, chromium, cobalt and mercury. They can be planted on toxic waste sites where they remove the toxic metals from the soil. The Indian mustard (Brassica juncea) has the

areas fulfils all the needs of the

developing

disease

resistant

varieties. It was evident in the early 1970s when an epidemic called grassy stunt disease of rice caused by virus destroyed more than 160,000 hectares of the crop in Asia. A resistance gene borrowed from

wild rice variety of Central India named Oryza nivara controlled the disease. It was the only known genetic source of resistance to the grassy stunt disease. Biodiversity plays an important role in protecting the water resources. The natural vegetation cover in water catchment helps in maintaining hydrological cycles, regulating and stabilizing water runoff and acts as buffer against natural disasters like flood and drought. Vegetation facilitates the percolation of water into the ground, thus helping in maintenance of ground water table.

The standing mangrove vegetation along the sea coast serves as a shield against natural disasters like cyclone and tsunami. Biodiversity plays significant role in soil formation and its protection. The vegetation improves the soil structure, increases the water holding capacity of the soil and also raises the nutrient level of the soil. Biological

diversity

plays

important role in nutrient recycling. It is the sink and source of nutrients. Microbes in the soil, facilitating the nutrient return to the soil decompose the dead plant parts and animals. 58

environmental

pollution

.

tribals. Due to constant association with the forest environment tribals have evolved a curious knowledge of plants and their utility for them. Many of the uses for which plant tribals employ products are not known outside their restricted community.

Biodiversity of India

used for disposition and extraction

With 2.4 per cent of the world’s land, India contributes 8 per cent to the world diversity. It has, therefore, been designated as one of the 12 megadiversity regions of the world. India is recognized as a country uniquely rich in biodiversity because of its tropical location, varied physical features and climate. Indian biodiversity is estimated to be over 45,000 plant

of metals like copper, cadmium,

species contributing 8 per cent of the

iron and mercury from water.

world’s flora and about 80,000

ability to

absorb

cadmium

and

chromium from the soil. Aquatic plants like Eichhornia crassipes, Lemna minor and Azolla pinnata are

Forests comprising diverse group of plant species are the major sinks of carbon dioxide. The latter serve as a green house gas causing global warming. Thus ecologically diverse forest ecosystems help in mitigation of global warming.

Biodiversity provides stability to the ecosystem and maintains the ecological balance. Plants and animals in ecosystem are linked to each other through food chain and food web. The loss of one species in the ecosystem affects the survival of other species. Thus the ecosystem becomes fragile.

animal species constituting 7 per cent of the world’s fauna of which 33 per cent flora and 62 per cent fauna are endemic (found nowhere else in the world) to India. Among the plant species, the flowering plants have a much higher degree of endemism, a third of these are not found elsewhere in the world. Of the estimated 45,000 species of plants about 5,000 species of algae, 20,000 of fungi, 1,600 of lichens, 2,700 of bryophytes, 600 of pteridophytes and 15,000 of flowering plants have been identified and described so far. Indian flowering plants represent 15 per cent of the flowering plants

YOJANA August 2010

of the world. Among flowering plants orchids have high species diversity (1,082) found mainly in North-eastern Himalaya. Apart from the high biological diversity in Indian wild plants there is also great diversity of cultivated crops. The traditional cultivar includes 30,000 to 50,000 varieties of rice and a number of cereals, vegetables and fruits. The highest diversity of cultivars is concentrated in high rainfall areas of the Western Ghats, Eastern Ghats, Northern Himalayas and the North-Eastern hills. As far as faunal diversity is concerned, India is home for 67,000 species of insects (including 13,000 butterflies and moths), 4,000 of molluscs, 6,500 other invertebrates 2,000 of fishes, 1,200 of birds, 540

of reptiles, 200 of ambhibians, and 500 of mammals, in which 62 per cent ambhibians and 32 per cent reptiles are endemic to India. Among lizards, of the 153 species recorded 50 per cent are endemic. Among the larger animals 79 mammals, 44 birds, 15 reptiles and 3 amphibians are threatened today and 1,500 plant species belong to endangered category (the species which are in danger of extinction). Indian sub-continent alone has given the world nearly 320 species of wild animals, whose centre of origin lies in India. Livestock diversity is also high i.e. 27 breeds of cattle, 40 breeds of sheep, 22 breeds of goats and 8 breeds of YOJANA August 2010

buffaloes are available in the country. However, today many of these are standing on the verge of extinction due to the increased use of exotic breeds. Jersey and Holsteins have largely replaced indigenous breeds of cattle. India has contributed 167 species of cultivated plants along with their 320 species of wild relatives and land races and several domestic animals. Rice, sugarcane, jute, jackfruit, ginger, turmeric, black pepper, bamboos, camel, mithun and water buffalo have originated in India. India is extremely rich in Ecosystem diversity as well. According to Wildlife Institute of India the country has 10 biographic zones: (i) TransHimalayas (ii) Himalayas (iii) Desert (iv) Semi-arid (v) Western Ghats (vi) Deccan (vii) Gangetic Plain (viii) North-East India (ix) Islands; and (x) Coasts The North-East, the Western Ghats, Western and NorthWestern Himalayas are rich in endemism. At least 200 endemic species are found in the Andaman and Nicobar islands. Hot spots are the regions of high biodiversity with massive threat to flora and fauna due to high biotic pressure. Of the 18 biodiversity hot spots of the world 2 belong to India. Western Ghats and Eastern-Himalayas are the hot spots of biodiversity in India. The Andaman and Nicobar islands are extremely rich in

species, and many subspecies of different animals and birds have evolved here. The islands alone have as many as 2,200 species of flowering plants and 120 species

of ferns. Out of 135 genera of land mammals in India 85 (63%) are found in the north-east. The

north-eastern states also have 1,500 endemic plant species. A major proportion of amphibian and reptile species, especially snakes, is concentrated in Western Ghats, which is also habitat for 1,500 endemic plant species. The Coral reefs around the Andaman and Nicobar islands, the Lakshadweep islands and the Gulf areas of Gujarat and Tamil Nadu are biologically diverse ecosystems and are often called ‘tropical rain forest’ of the ocean. Causes of loss of biodiversity The fundamental causes of biodiversity loss include: 1. Unsustainably high rates of human population growth and natural resource consumption. 2. Introduction of exotic species associated with agriculture, forestry and fisheries. 3. Economic systems and policies that fail to value the environment and its resources. 4. Inequity in ownership and access to natural resources, including the benefits from use and conservation of biodiversity. 5. Inadequate knowledge and inefficient use of information. 59

6. Legal and institutional systems that promote unsustainable exploitation. Conservation of Biodiversity Conservation of biodiversity refers to planning and management of biological resources in a way so as to secure their wide use and continuous supply, maintaining their quality, value and diversity. The World Conservation Strategy has suggested the following steps for biodiversity conservation:

1) Efforts should be made to preserve the species that are endangered. 2) Prevention of extinction requires sound planning and management. 3) Varieties of food crops, forage plants, timber trees, livestock, animals and their wild relatives should be preserved. 4) Each country should identify habitats of wild relatives and ensure their protection. 5) Habitats where species feed, breed, nurse their youngs and rest should be safeguarded and protected. 6) International trade in wild plants and animals be regulated.

For the conservation of biodiversity the immediate task will be to devise and enforce time bound programme for saving plant and animal species as well as habitats of biological resources. Action plan for conservation, therefore must be directed to: i) Inventorization of biological resources in different parts of 60

the country including the island ecosystems. ii) Conservation of biodiversity through a network of protected areas including National Parks, Sanctuaries, Biosphere reserves, Gene Banks, Wetlands, Coral reefs etc. iii) Restoration of degraded habitats to their natural state. iv) Reduction of anthropogenic pressure by cultivating the species elsewhere. v) Rehabilitation of the threatened and endangered species. vi) Protection and sustainable use of genetic resources/germplasm through appropriate laws and practices. vii) Conservation of microbes which help in reclamation and rehabilitation of wastelands and revival of biological potential of land. viii)Control of over-exploitation through Convention on International Trade in Endangered Species (CITES) and other agencies. ix) Rehabilitation of tribals displaced owing to creation of protected areas. x) Protection of domesticated plant and animal species in order to conserve indigenous genetic diversity. xi) Multiplication and breeding of threatened species through modern techniques of tissue culture and biotechnology. xii) Maintenance of corridors between different nature

reserves for the possible migration of species in response to climate, or any other disturbing factor. xiii)Restriction on the introduction of exotic species without adequate investigation. xiv) Support for protecting traditional indigenous knowledge and skills for conservation. xv) Discouragement of monoculture plantations. There are two main categories of biodiversity conservation: Ex situ conservation and In situ conservation: 1. Ex situ conservation: This is conservation outside their habitats by perpetuating sample population in genetic resources centres, zoos, botanical gardens, culture collection etc. or in the form of gene pools, and gamete storage for fish; germplasm banks for seeds, pollen, semen, ova, cells etc. In this type of conservation, plants are maintained more easily than animals. Seed banks, botanical gardens, pollen storage, tissue culture and genetic engineering have been playing important role. India has done commendably well as far as ex situ conservation of crop genetic resources is concerned. Gene banks have collected over 34,000 cereals and 22,000 pulses grown in India. It has also taken up such work on livestock, poultry and fish genetic resources. However, there is need to develop facilities for YOJANA August 2010

long and medium term conservation through : i) Establishment of Genetic Enhancement Centres for producing good quality of seeds. ii) Enhancement in the existing zoos and botanical garden network. iii) Seed-gene banks. iv) Tissue culture gene banks v) Pollen and spore banks vi) Captive breeding in zoological gardens; and vii) In vivo and in vitro preservation 2. In situ conservation : This is the conservation of genetic resources through their maintenance within natural or even human made ecosystem in which they occur. This type includes a system of protected areas of different categories, managed with different objectives to bring benefit to the

society. Strict Nature Reserve/ Wilderness Area, National Parks, National Monuments/ Natural Landmark, Habitat/ Species Management Area, Protected Landscapes and Seascapes, Managed Resource Protected Area, Wildlife sanctuaries and Biosphere Reserves belong to this type of conservation. Protected Area Network in India The protected areas in India includes National Parks, Wildlife Sanctuaries and Biosphere

Reserves. YOJANA August 2010

National Parks: These are areas dedicated to conserve the scenery, natural objects and the wildlife therein. In these areas, all private rights

are

non-existent,

forestry

operations and grazing of domestic animals are prohibited. Certain parts of the parks are developed for tourism, enjoyment and study in such a way that it will not disturb or scare the animals. The boundaries of the National Parks are circumscribed by legislation. There are 89 National Parks in India, occupying nearly 4.1 million hectares (1.25%) of the land area of

the country. Wildlife Sanctuaries: These are dedicated to protect the wildlife, and their boundaries are not limited by state legislation. In a sanctuary, killing, hunting or capturing of any species of birds and mammals is prohibited except by, or under the control of the highest authority in the department responsible for management of a sanctuary. Forestry and other usages are permitted to the extent that they do not adversely affect the wildlife.. India has 500 wildlife sanctuaries occupying about 12 million hectares (3.6%) of land area of the country.

Biosphere Reserves: These are multipurpose protected areas which are meant for preserving genetic diversity in representative ecosystems by protecting wild populations, traditional life style of tribals and domesticated plant/ animal genetic resources. Each biosphere reserve has following zones:

i) Core zone: where no human activity is allowed. ii) Buffer zone: Limited human activity is allowed. iii) Manipulation zone: Human activity is allowed but ecology is not permitted to be disturbed. iv) Restoration zone: Degraded area for restoration to natural or near natural form. Nilgiri Biosphere reserve was the first biosphere reserve of India

established in 1986. Today there are 15 Biosphere Reserves in India, three of which i.e. Sunderban, Gulf of Mannar and Agasthymalai Biosphere Reserves have been improved as World Biosphere Reserves by United Nations Educational, Scientific and Cultural

Organization (UNESCO). Conclusion In a biodiversity rich developing country like India the fast growing human population has put tremendous pressure on biological resources. Hence unsustainable use of the biological resources has resulted in the loss of biological diversity of the country. Besides this, introduction of exotics have also substantially contributed to the loss of biological wealth of the country. Therefore, conservation of biodiversity is the need of the hour not only for the fulfillment of food,

fodder, fuel, timber and medicinal requirements but also for the enhanced agricultural production, ecological balance, mitigation of environmental pollution and natural calamities.  (E-mail: [email protected])

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