Biodiversity and its Conservation

Transcription

1 Biodiversity and its Conservation

2 INTRODUCTION Biodiversity is the degree of variation of life forms within a given ecosystem, biome, or an entire planet. Biodiversity is the variety of the world s organisms, including their genetic diversity and the assemblage Biodiversity is a measure of the health of ecosystems.

3 INTRODUCTION Genes are component of species & species are component of ecosystem. Therefore, altering the make-up of any level of this can change the other species are the concept of this. Biodiversity is in part a function of climate. In terrestrial habitats, tropical regions are typically rich whereas polar regions support fewer species

4 (1) Genetic Diversity: It s a concept of the variability within species, as measured by the variation in genes within a particular species, variety, subspecies, or breed. Ex: all rice varieties belong to species Oryza sativa, but thousand of wild & cultivated varieties of rice which show variation at genetic level & differ in their colour, size, shape & aroma, nutrient content. This is genetic diversity of rice. Importance: Various applications of biotechnology such as crop & animal breed, improvement, depend upon the identification of genetic material for incorporating desirable traits.

5 (2) Species Diversity: Richness of species in an ecosystem is called species diversity. Species diversity means variety of living organisms on earth.

6 (3) Ecosystem diversity: It shows variations in ecological niches, trophic structure, food webs, nutrient cycling & also in physical parameters such as moisture, temperature, precipitation etc. Ex: grasslands, wetlands, rivers fresh water etc. Ecosystem diversity assessment may include estimation of richness in particular groups & evolution of their relative abundance.

7 Values of biodiversity: It is classifies into two: [1]Direct value: direct in agriculture, medicine & industry. These can be estimated by observing the activities of representative group of people, by monitoring collection point for normal products & by examining export/import statistics. It is also classified into two:

8 (i) Consumptive use value: This value is assigned where the biodiversity product can be harvested & consumed directly. Ex: fuel, food, drug etc. (ii) Productive Use value: These are commercially usable values where the product is marketed & sold in commercial markets. Ex: silk from silk worm, wool from sheep etc.

9 [II] Indirect values: These benefits ecosystem services, such as air & water purification, climate regulation & generation of moisture & oxygen. Ex: small animals like earthworms, insects, millipeds help to give soil its texture & fertility and are crucial for aeration. Rainforest tree in 100 years of lifespan can transfer 2.5 million gallons of water from soil to air. So, their roles are crucial in hydrological cycle. - It can be classifies into following:

10 (i) Non-consumptive/use value: It involves benefits such as soil protection/formation, climate regulation, air purification, medical research etc. (ii) Asthetic value: Natural & wild landscapes are aesthetically & provide opportunities to get away from human dominated landscapes. Ex: Wild life conservation, national parks, zoological & botanical gardens etc.

11 (iii) Social & cultural values: They are associated with social life, customs, religion & psycho-spiritual aspects of life. Ex: Tulsi, Lotus, Bael, Cow, Bull, Owl etc. (iv) Ethical value: It involves moral justification for conservation of biodiversity. These values are based on the belief that all species have a moral right to exist, independent of our need for them. Ex: Boycott of furs, animal skins etc. (v) Option Value: Value is the value of knowing that there are biological resources existing on existing, that may one day prove to be an effective option for

12 BIO-GEOGRAPHICAL CLASSIFICATION OF INDIA Bio-geographic classification of India was done by Rodgers and Panwar (1988), describing 10 biogeographic zones in India, further divided into 25 biogeographic provinces. The classification was done using various factors such as altitude, moisture, topography, rainfall, etc. Biogeographic zones were used as a basis for planning wildlife protected areas in India.

13 BIO-GEOGRAPHICAL CLASSIFICATION OF INDIA From the stand point of biodiversity, India is given the status of a Mega-diversity zone. There are 10 biogeographic zones witch are distinguished clearly in India. They are as follows a) Trans Himalayan zone. b) Himalayan zone. c) Desert zone. d) Semiarid zone. e) Western ghat zone. f) Deccan plateau zone. g) Gangetic plain zone. h) Coast i) North east zone. j) Islands present near the shore line.

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15 THE COUNTRY HAS 10 DIFFERENT BIO GEOGRAPHIC ZONES AND 26 BIOTIC PROVINCES: Bio geographic Zones Trans-Himalayas Biotic provinces Ladakh mountains, Tibetan plateau Himalayas Northwest, west, central and east Himalayas Desert Semi-arid Thar, Kutch Punjab plains, Gujarat Rajputana Western Ghats Deccan Peninsula Malabar plains, Western Ghats Central highlands, Chotta-Nagpur, Central Plateau, Deccan South Gangetic Plains Upper and Lower Gangetic plains Coast West and East coast, Lakshadweep North-East Brahmaputra valley, Northeast hills Islands Andaman and Nicobar

16 1. TRANS-HIMALAYAN REGION The Himalayan ranges immediately north of the Great Himalayan range are called the Trans- Himalayas..

17 The Trans-Himalayan region with its sparse vegetation has the richest wild sheep and goat community in the world. The snow leopard is found here, as is the migratory black-necked cranes.

18 2. HIMALAYAS The Himalayas consist of the youngest and loftiest mountain chains in the world.

19 The forests are very dense with extensive growth of grass and evergreen tall trees. Oak, chestnut, conifer, ash, pine, deodar are abundant in Himalayas. There is no vegetation above the snowline. Several animals live in the Himalayan ranges. Chief species include monal, wild sheep, mountain goats, ibex, shrew, and tapir. Panda and snow leopard are also found here.

20 3. SEMI-ARID AREAS Adjoining the desert are the semi-arid areas, a transitional zone between the desert and the denser forests of the Western Ghats.

21 The natural vegetation is thorn forest. This region is characterized by discontinuous vegetation cover with open areas of bare soil and soil-water deficit throughout the year. A few species of xerophytic herbs and some ephemeral herbs are found in this semi-arid tract. Asiatic lions, Birds, jackals, leopards, eagles, snakes, fox, buffaloes are found in this region.

22 4. WESTERN GHATS The mountains along the west coast of peninsular India are the Western Ghats, which constitute one of the unique biological regions of the world. The Western Ghats extend from the southern tip of the peninsula (8 N) northwards about 1600 km to the mouth of the river Tapti (21 N). The mountains rise to average altitudes between 900 and 1500 m above sea level.

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24 Apart from biological diversity, the region boasts of high levels of cultural diversity, as many indigenous people inhabit its forests. The Western Ghats are amongst the 25 biodiversity hotspots recognized globally. These hills are known for their high levels of endemism expressed at both higher and lower taxonomic levels. Most of the Western Ghat endemic plants are associated with evergreen forests. Rice cultivation in the fertile valley proceeded gardens of early commercial crops like areca nut and pepper. The Western Ghats are well-known for harboring 14 endemic species of caecilians (i.e., legless amphibians) out of 15 recorded from the region so far.

25 5. NORTH-WEST DESERT REGIONS This region consists of parts of Rajasthan, Kutch, Delhi and parts of Gujarat. The climate is characterized by very hot and dry summer and cold winter. Rainfall is less than 70 cms.

26 The plants are mostly xerophytes. Babul, Kikar, wild palm grows in areas of moderate rainfall. Indian Bustard, a highly endangered bird is found here. Camels, wild asses, foxes, and snakes are found in hot and arid deserts.

27 6. DECCAN PLATEAU Beyond the Ghats is Deccan Plateau, a semi-arid region lying in the rain shadow of the Western Ghats. This is the largest unit of the Peninsular Plateau of India.

28 The highlands of the plateau are covered with different types of forests, which provide a large variety of forest products. Fauna like tiger, sloth bear, wild boar, gaur, sambar and chital are found throughout the zone along with small relict populations of wild buffaloes, elephants and barasingha.

29 7. GANGETIC PLAIN In the North is the Gangetic plain extending up to the Himalayan foothills. This is the largest unit of the Great Plain of India. The Great Plains cover about 72.4mha area with the Ganga and the Brahmaputra forming the main drainage axes in the major portion.

30 The physiographic scenery varies greatly from arid and semi-arid landscapes of the Rajasthan Plains to the humid and per-humid landscapes of the Delta and Assam valley in the east. The plain supports some of the highest population densities depending upon purely agro-based economy in some of these areas. The trees belonging to these forests are teak, sal, shisham, mahua, khair etc.

31 8. NORTH-EAST INDIA North-east India is one of the richest flora regions in the country. It has several species of orchids, bamboos, ferns and other plants. Here the wild relatives of cultivated plants such as banana, mango, citrus and pepper can be found.

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33 9. ISLANDS The two groups of islands, i.e., the Arabian Sea islands and Bay Islands differ significantly in origin and physical characteristics. The Arabian Sea Islands (Laccadive, Minicoy, etc.) are the foundered remnants of the old land mass and subsequent coral formations. On the other hand, the Bay Islands lay only about 220 kms.

34 Away from the nearest point on the main land mass and extend about 590 kms. With a maximum width of 58 kms the island forests of Lakshadweep in the Bay of Bengal have some of the best-preserved evergreen forests of India. Some of the islands are fringed with coral reefs. Many of them are covered with thick forests and some are highly dissected.

35 10. COASTS o India has a coastline extending over 5,500 kms. The west coast is narrow except around the Gulf of Canbary and the Gulf of Kutch. o In the extreme south, however, it is somewhat wider along the south Sahyadri. The backwaters are the characteristic features of this coast.

36 o Extensive deltas of the Mahanadi, Godavari, Krishna and Kaveri are the characteristic features of east coast. Mangrove vegetation is characteristic of estuarine tracts along the coast for instance, at Ratnagiri in Maharashtra. o Larger parts of the coastal plains are covered by fertile soils on which different crops are grown. Rice is the main crop of these areas. Coconut trees grow all along the coast.

37 HOT SPOTS OF BIODIVERSITY Areas which exhibit high species richness as well as high species endemism is called as hot spots of biodiversity. There are 35 such hot spots on a global level and only two of which are in India, namely Eastern Himalayas and Western Ghats. These hot spots cover less than 2% of the world land area and have about 50% of terrestrial biodiversity. Two hot spots in India are: (i) (ii) Indo-Burma region covering Himalayas Western-Ghats-Srilanka region

38 THREATS TO BIODIVERSITY Elimination of species is a natural process is known as species extinction. Human actions causes extinction of biodiversity as follows: (i) Loss of Habitat (ii) Poaching (iii) Man-Wildlife Conflicts

39 (I) HABITAT LOSS & DEGRADATION (i) Pollution: various human activities like industries, automobiles etc. pollutes water & air bodies. Ex: population of fish eating birds are greatly decline due to DDT deposition in the fish which was sprayed in water to kill mosquitoes. (ii) Introduction of exotic species: A species entering in new geographical area is called exotic species. Main cause is accidental transport, agriculture etc. ex: Nile Perch an exotic predatory fish introduced in lake Victoria has threatened the entire ecosystem by eliminating small fishes.

40 (iii) Disease: Polluted water & soil may act as disease causing & killing agent for biodiversity. (iv) Over-exploitation: Growing rural poverty, increasingly efficient methods of harvesting & globalization of the economy combine to exploit species to the point of extinction. (v) Shifting: Some rural people destroy biological communities & hunt endangered species because they are poor & have no land of their own.

41 (vi) Natural calamities (vii) Global warming & acid rain: Affects climate, ecology, agriculture, aquatic & terrestrial ecosystem.

42 [II] POACHING It is the illegal trade of wildlife products by killing prohibited endangered animals. Animals are killed for skin, meat & internal organs as well as for sport & accidental killing. Measures for prevention: 1.Ban on illegal trade. 2. Prepare a database of wildlife related crimes. 3. Establish trans-boundary control posts. 4. Develop collaborative partnerships with all commercial logging & transport companies.

43 [III] MAN WILDLIFE CONFLICT This occurred due to expansion of human populations towards the natural habitats of wildlife. Animals may move out of forest to search of food. Generally ill, weak & injured animals have a tendency to attack man. Some of the incidents are: In Orissa 195 humans were killed in last 5 years by elephants. Thus villagers killed98 elephants.

44 Prevention: 1. Adequate crop compensation & cattle compensation scheme must be started. 2. Cropping pattern should be changed near forest borders. And adequate fodder should be available for animals in forests. 3. Wild life corridors should be provided for mass migration of big animals.

45 CONSERVATION OF BIODIVERSITY 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 need & aspirations of future generations.

46 OBJECTIVES To maintain essential ecological processes & life supporting systems. To preserve the diversity of species. To ensure sustainable utilization of species & ecosystem which support milllions of rural communities as well as major industries.

47 [I] In Situ Conservation: It deals with conservation of living resources through their maintenance within the natural ecosystem in which they occur. This is done using biosphere reserves, national parks and wildlife sanctuaries. (i) National parks: Its an area strictly reserved to the betterment of the wildlife & their activities such as forestry, grazing or cultivation are not permitted, and no private ownership is allowed.

48 (ii) Sanctuary: It is generally species oriented. Operations such as harvesting of timber, forest products & private ownerships are permitted as long as they don t interfere with well being of animals. (iii) Biosphere Reserves: It is undisturbed natural areas for scientific study as well as areas where any sort of disturbance is under control. They have been set for ecological research & habitat preservations.

49 The zones of biosphere reserve: a) Core zone: No human activity is allowed in this zone. Comprises of legally protected ecosystem. b) Buffer zone Limited human activity is permitted in the buffer zone. c) Manipulation zone or Transition zone Several human activities can occur in the manipulation zone. Example: Settlements, cropping, forestry, recreation etc.

50 Characteristics: 1. Contain abundant genetic diversity 2. Biosphere should be unique. 3. Should have sufficient energy resources. 4. Have legal protection.

51 ROLE OF BIOSPHERE RESERVES A biosphere reserve preserves a) wild population b) life style of tribal c) genetic resources of domesticated plants and animals. It helps in 1) Conservation 2) promotes economic development 3) Scientific research, monitoring and education.

52 EX-SITU CONSERVATION Conservation out side the habitats. (i) Zoos: It s the place where animals are kept for public showing. (ii) Botanical gardens: Important role in conservation of plant species. Record of plants that are in cultivation have been kept in GREEN BOOKS (acc. To botanical survey of India) Has a special role in active research & action oriented plan for conservation.

53 (iii) Seed Banks: Seeds have to be stored under minimal life so that they can be kept for several years without accumulations of mutations & with minimum loss of viability It can be done with cold storage. (iv) Pollen storage: For conservation of genetic diversity.

54 (v) Tissue culture: Best method for preservation of tissue banks. Low maintenance cost. genes through Protection of genotypes from natural calamities & diseases.

55 ADVANTAGES OF EX-SITU CONSERVATION Organisms is assured of food, shelter & security & hence can have longer life span & breeding. Chances of survival are enhanced. Also provides the possibility of using genetic techniques to improves the concerned species.

56 DISADVANTAGES Employed to selective species because of limitation of space, finance & facilities. New life forms can not be evolve & gene pools get stagnant.