Unit 4: Biodiversity and Conservation
BIODIVERSITY AND ITS CONSERVATION
4.1 Introduction:
It is really amazing , if we divide the whole mother earth into 10 billion parts, it is only one part where life exists and the surprising variety of living organisms which could be about 50 million species are all restricted to just about a kilometer –thick layer of soil, water and air. It is indeed wonderful to see that so much diversity has been created by nature on this earth from so little physical matter. Biodiversity refers to the variety and variability among all groups of living organisms and the ecosystem complexes in which they occur. Biodiversity constitutes the biological wealth.
Importance of biodiversity
Biodiversity conservation, the practice of protecting and preserving the wealth and variety of species, habitats, ecosystems, and genetic diversity on the planet, is important for our health, wealth, food, fuel, and services we depend on. Biodiversity conservation is vital for economic growth and poverty reduction. This has created a great imbalance in nature. Thus, the importance of biodiversity has to be understood and actions have to be taken to maintain all the three levels of diversities.
4.2. Biogeographic Classification of India:
India is country of vast biodiversity. It is divided into different regions based on the geography, climate and pattern of vegetation seen and the communities of mammals, birds, reptiles, amphibians, insects and other invertebrates that live in them. Each of these regions contains a variety of ecosystems such as forests, grasslands, lakes, rivers, wetlands, mountains and hills, which have specific plant and animal species.
Biogeographic classification of India is the division of India according to biogeographic characteristics. Biogeography is the study of the distribution of species (biology), organisms, and ecosystems in geographic space and through geological time. There are ten biogeographic zones in India. 1. Trans Himalayan zone.
2. Himalayan zone
3. Desert zone.
4. Semiarid zone.
5. Western Ghat zone.
6. Deccan plateau zone.
7. Gangetic plain zone.
8. North east zone.
9. Coastal zone.
10. Islands present near the shore line.
Trans-Himalayan region
The Himalayan ranges immediately north of the Great Himalayan range are called the Trans- Himalayas. 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 crane.
Himalayas
The Himalayas consist of the youngest and loftiest mountain chains in the world. The Himalayas have attained a unique personality owing to their high altitude, steep gradient and rich temperate flora.
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 interesting animals live in the Himalayan ranges. Chief species include wild sheep, mountain goats, ibex, shrew, and tapir. Panda and snow leopard are also found here.
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. 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.
Thorny shrubs, grasses and some bamboos are present in some regions. A few species of xerophytic herbs and some ephemeral herbs are found in this semi-arid tract. Birds, jackals, leopards, eagles, snakes, fox, buffaloes are found in this region.
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, intercepting monsoon winds from the southwest and creating a rain shadow in the region to their East.
The varied climate and diverse topography create a wide array of habitats that support unique sets of plant and animal species. 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 hot-spots 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.
Expansion of traditional agriculture and the spread of particularly rubber, tea, coffee and forest tree plantations would have wiped out large pockets of primary forests in valleys. The Western Ghats are well known for harboring a large number of endemic species of caecilians (i.e., legless amphibians) out of 15 recorded from the region so far.
North-West Desert Regions
This region consists of parts of Rajasthan, Kutch, Delhi and parts of Gujarat. The climate is characterized by very hot, dry summer and cold winter. Rainfall is less than 70 cm. The plants are mostly xerophytic. 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.
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. The highlands of the plateau are covered with different types of forests, which provide a large variety of forest products. The Deccan plateau includes the region lying south of the Satpura range.it extends up to the southern tip of peninsular India. Anaimudi is the highest peak of this region.The Deccan plateau is surrounded by the Western and the Eastern Ghats. These Ghats meet each other at the Nilgiri hills. The Western Ghats includes the Sahyadri, Nilgiris, Anamalai, and cardamom hills. Many rivers such as Mahanadi, Godavari, Krishna, and Kaveri originates from Western Ghats and flow toward the east.The Eastern Ghats are broken into small hill ranges by river coming from the Western Ghats. Most of these rivers fall into the bay of Bengal.The Godavari is the longest river in the Deccan plateau .Narmada and the Tapi flow westwards and fall into the Arabian sea.
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. Ganga is the main river after whose name this plain is named. The aggradational Great Plains cover about 72.4mha area with the Ganga and the Brahmaputra forming the main drainage axes in the major portion.
The thickness in the alluvial sediments varies considerably with its maximum in the Gangetic plains. The physio geographic 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.
Topographic uniformity, except in the arid Western Rajasthan is a common feature throughout these plains. 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.
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 grown.
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 Km.
Away from the nearest point on the main land mass and extend about 590 Km. With a maximum width of 58 Km the island forests of Lakshadweep in the Arabian Sea 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.
Coasts
India has a coastline extending over 5,500 km. The Indian coasts vary in their characteristics and structures. The west coast is narrow except around the Gulf of Cambay and the Gulf of Kutch. In the extreme south, however, it is somewhat wider along the south Sahyadri.
The backwaters are the characteristic features of this coast. The east coast plains, in contrast are broader due to depositional activities of the east-flowing rivers owing to the change in their base levels.
Extensive deltas of the Godavari, Krishna and Kaveri are the characteristic features of this coast. Mangrove vegetation is characteristic of estuarine tracts along the coast for instance, at Ratnagiri in Maharashtra.
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.
4.3 Value of Biodiversity
As all the organisms in an ecosystem are interlinked and interdependent, the value of biodiversity in the life of all the organisms including humans is enormous.
• Loss of biodiversity contributes to climatic change.
• Forest converts carbon dioxide into carbon and oxygen. Loss of forest covers due to release of carbon dioxide and other gases due to industrialization, contributes to ‘Green House Effect’. This leads to Global warming which results in raise in sea-level submerging the low-lying areas in the world and causing atmospheric changes.
• Biological diversity is also essential for preserving ecological processes.
• Tribal communities who directly gather resources from the forest or fisher folk who catch fish in marine or freshwater ecosystems are directly or indirectly linked to the biological variety present in the biosphere.
• For agricultural communities, biodiversity is used to grow their crops to suit the environment. • Urban communities generally use the greatest amount of goods and services, which are all indirectly drawn from natural ecosystems.
• Preservation of biological resources is essential for the well-being and long-term survival of mankind.
Biodiversity everyday around the globe is being lost and some species are being pushed towards extinction. Evolution also brought forth new life forms, replacing species that were lost. Today we are losing about 1500 species every two months.
Some of the major values of biodiversity are as follows:
1. Consumptive value 2. Productive Value 3.Social Value 4.Ethical Value 5.Aesthetic Value and 6.Option value.
4.3.1 Consumptive use
The value of Nature’s Products that are consumed directly such as firewoods , fodder and meat. In other words the products which are consumed directly without passing through the market .Consumptive use value seldom appear in National income accounts.
• A straight forward example is the direct utilization of timber, food, fuel wood and fodder by local communities.
• The biodiversity contained in the ecosystem provides forest dwellers with all their daily needs, food, building material, fodder, medicines and a variety of other products. They are well-known about the qualities and different uses of wood from different species of trees, and collect a large number of local fruits, roots and plant material that they use as food, construction material or medicines.
• Fisher folks are completely dependent on fish and know where and how to catch fish and other edible aquatic animals and plants.
4.3.2 Productive use
These are the direct use values where the product is commercially sold in national and international market. Many industries are dependent upon these values. Example: Textile, leather, silk, paper and pulp industry etc. There is an international ban on trade of products from endangered species like tusks of elephants, wool from sheep, fur of many animals etc.
4.3.3 Social values
Social value of Biodiversity in India is particularly important for its religious,spiritual and other cultural uses. Many plants and animals have ritual significance. The entire ecosystem is utilized for cultural and spiritual purposes.Some examples among auspicious flowers offered in temples are Hibiscus (Shoe flower) offered to the goddess Kali, Datura (Ummam) flowers to God Siva. A network of sacred groves is still in evidence in some parts of India.
4.3.4 Ethical values
Ethical values are economic arguments that can be advanced to justify the protection of biological diversity. Ethical arguments assert that humans have a duty to protect species based on their intrinsic value, unrelated to human needs.
People do not have the right to destroy species and should take action to prevent their extinction. 4.3.5 Aesthetic value
Regardless of our own material self-interest, we should treat nature respectfully. Enlightened self interest, arguing that preserving biodiversity and developing our knowledge of it will make us better and happier people. Symbols from wild species such as the lion of Hinduism, the elephant of Buddhism and the vehicles of several deities are animals that have been venerated for thousands of year. The sacred Basil or the ‘Tulsi’ has grown in the courtyards of household for centuries.
4.3.6 Option values
Keeping future possibilities open for their use is called the option value. It is impossible to predict which of our species or traditional varieties of crops and domestic animals will be greatest use in the future.
4.4 India as a Mega-Diversity Nation
India is very rich in the diversity of plants and animals, so it is called as mega diversity center.Mega means large, so mega diversity means a large number and wide range of species present in an ecosystem.
India recorded:
• 45,000 + species of wild plants
• 89,000 + species of wild animals
• 320 species of wild relatives of crops have been originated here.
• 1,39,000 species of plants, animals and microbes are recorded ϖ More than 4 lakh species are yet to be identified
4.5 Hot-Spots of Biodiversity
It is a biogeographic region with a significant reservoir of biodiversity, that is under threat from humans. Concept was first introduced by Norman Myer. Twenty five hotspots have been identified all over the world.
Important hot spots are
1 .Western Ghats and Sri Lanka
2. Eastern Himalaya
3. Mediterranean basin
4. Indo-Burma
5. Horn of Africa
6. Madagacsar and Indian Ocean islands
7. Sundaland
8. Forests of Australia
9. Caucasus
10. Mesoamerica
Two out of ten hot spots are located in India ( Western Ghats and hilly regions of north east Himalaya).
4.6.Threats to Biodiversity
4.6.1. Habitat loss
Habitat loss can be described when an animal loses their home. Every animal in the animal kingdom has a niche (a comfortable or suitable position).
Reasons of habitat loss caused by humans:
• Agriculture and farming
• Harvesting natural resources for personal use
• For industrial and urbanization development
Habitat destruction is currently ranked as the primary causes of species extinction worldwide. Example: The impact upon China’s panda, once found across the nation. It is now only found in fragmented and isolated regions in the south west of the country as a result of wide spread deforestation in the 20th century.
Natural causes of habitat are volcanic eruption,, fire and climatic changes.
Solutions for habitat loss are:
• Protecting the remaining sections of natural habitats.
• Reduce human population and expansion of urbanization and industries.
• Educating the public about the importance of natural habitat and bio diversity. 4.6.2 Poaching of wildlife
Poaching is the hunting and harvesting, taking of wild plants or animals. It is for large profits gained by the illegal sale or trade of animal parts, and meat. Many cultures believe that certain animal parts have medicinal value. Poaching or illegal hunting endangers animals. If more animals becomes extinct there's a disruption in the food chain, and that will cause major problems in our ecosystem, resulting eventually in new adaptations of animals, and or species beyond human control.
4.6.3 Man-wildlife conflicts
Any conflict that arises where the behavior of one (human or wildlife) is unacceptably disadvantageous to other.Increase in man wildlife conflict is due to resource limitations such asfood, shelter and space. It is also due to increasing population of human beings, loss of forest, and decrease in the quality of forest and development activities.
4.7 Endangered and Endemic Species of India
The endangered species are those living organisms which are almost on the critical level of being extinct. Thousands of species of plants and animals are endangered and the number increases each year. World Wildlife Federation (WWF) published a book containing the details of endangered and threatened species of Flora and Fauna called as RED DATA BOOK or RED LIST BOOK. The RED DATA BOOK symbolizes a warning signal for those species which are endangered and have to be protected. Otherwise they are likely to become extinct in the near future. Some examples for animals are red panda, Red fox, Python and Golden monkey. Plants like Cycasrevoluta, Rauwolfiaserpentina, Nepenthes etc.
An Endemic Species is one that is only found in that region and nowhere else in the world. As such they are of conservation concern, because they are not widespread and may be confined to only one or two protected areas. Some examples for endemic species of plants in India are:
4.7.1 IUCN Threat Categories
International Union for Conservation of Nature (IUCN), is a network of environmental organization for the Protection of Nature. The IUCN maintains the IUCN Red List of Threatened Species, a comprehensive assessment of the current risk of extinction of thousands of plant and animal species.The main aims of IUCN are;
• To convey the urgency of conservation issues to the public and policy makers. • To help the international community to try to reduce species extinction.
• To provide scientifically based information on the status of species and subspecies at a global level.
• To provide information to guide actions to conserve biological diversity.
4.7.2 Red Data Book
The IUCN Red List of Threatened Species also known as the IUCN Red List or Red Data List. The Red Data Book is the state document established for documenting rare and endangered species of animals, plants and fungi as well as some local sub-species that exist within the territory of the state or country. It uses a set of criteria to evaluate the extinction risk of thousands of species and subspecies.
4.8. Conservation of Biodiversity
Conservation of biological diversity is essential for the survival of the human race. Objectives and advantages of biodiversity conservation
• Conservation of biological diversity leads to conservation of essential ecological diversity to preserve the continuity of food chains.
• The genetic diversity of plants and animals is preserved.
• It ensures the sustainable utilisation of life support systems on earth.
• It provides a vast knowledge of potential use to the scientific community.
• A reservoir of wild animals and plants is preserved, thus enabling them to be introduced, if need be, in the surrounding areas.
• Biological diversity provides immediate benefits to the society such as recreation and tourism. • Biodiversity conservation serves as an insurance policy for the future
4.8.1 Types of conservation
In situ conservation: Faced with the conflict between development and conservation, many nations find it unrealistic and economically not feasible to conserve all their biological wealth. Invariably, the number
of species waiting to be saved from extinction far exceeds the conservation resources available. On a global basis, this problem has been addressed by eminent conservationists. They identified for maximum protection, certain ‘biodiversity hotspots’ regions with very high levels of species richness and high degree of endemism (that is, species confined to that region and not found anywhere else). Although all the biodiversity hotspots put together cover less than 2 percent of the earth’s land area, the number of species they collectively harbour is extremely high and strict protection of these hotspots could reduce the ongoing mass extinctions by almost 30 per cent.
In India, ecologically unique and biodiversity-rich regions are legally protected as biosphere reserves, national parks and sanctuaries. India now has 14 biosphere reserves, 90 national parks and 448 wildlife sanctuaries. India has also a history of religious and cultural traditions that emphasized protection of nature. In many cultures, tracts of forest were set aside, and all the trees and wildlife within were venerated and given total protection. Such sacred groves are found in Khasi and Jaintia Hills in Meghalaya, Aravalli Hills of Rajasthan, Western Ghat regions of Karnataka and Maharashtra and the Sarguja, Chanda and Bastar areas of Madhya Pradesh. In Meghalaya, the sacred groves are the last refuges for a large number of rare and threatened plants.
Ex situ Conservation:
In this approach, threatened animals and plants are taken out from their natural habitat and placed in special setting where they can be protected and given special care. Zoological parks, botanical gardens and wildlife safari parks serve this purpose. There are many animals that have become extinct in the wild but continue to be maintained in zoological parks. In recent years ex situ conservation has advanced beyond keeping threatened species in enclosures. Now gametes of threatened species can be preserved in viable and fertile condition for long periods using cryopreservation techniques, eggs can be fertilised in vitro, and plants can be propagated using tissue culture methods. Seeds of different genetic strains of commercially important plants can be kept for long periods in seed banks. Biodiversity knows no political boundaries and its conservation is therefore a collective responsibility of all nations. The historic Convention on Biological Diversity (‘The Earth Summit’) held in Rio de Janeiro in 1992, called upon all nations to take appropriate measures for conservation of biodiversity and sustainable utilisation of its benefits. In a follow-up, the World Summit on Sustainable Development held in 2002 in Johannesburg, South Africa, 190 countries pledged their commitment to achieve by 2010, a significant reduction in the current rate of biodiversity loss at global, regional and local levels.
QUESTIONS
SECTION A (2 MARKS)
1. What do you mean by Hotspots?
2. Name the hotspot centers of India.
3. What are the reasons of habitat loss caused by humans? 4. Give the solutions for habitat loss.
5. What is poaching? How does it affect biodiversity? 6. Explain endangered species with two examples. 7. What is Red data book? Give its importance. 8. Describe endemic species. What is IUCN? 9. Name the in-situ conservation centers of India. 10. List the ex-situ conservation centers in India.
SECTION B (5 Marks)
1. Enumerate the importance of Biodiversity. 2. What are the different biogeographic zones of India? 3. Write notes on species diversity of Himalayan zone. 4. Briefly describe “Trans Himalayan regions”. 5. Explain the biodiversity of Western Ghats. 6. Discuss the biodiversity of Gangetic plains. 7. Write notes on species diversity of “Islands”. 8. Enumerate the biodiversity of “Coast”.
9. What are the consumptive use values of biodiversity? 10. Describe productive values of biodiversity. 11. State the social values of biodiversity.
12. List out the ethical values of biodiversity.
13. What are the aesthetic values of biodiversity? 14. List out different hotspots of biodiversity centers in India. 15. How habitat loss affect biodiversity. Give example. 16. What is IUCN? Give its objectives.
SECTION C (15 Marks)
1. Write an essay on Biogeographic classification of India and explain “Biodiversity at Global, National and local levels”.
2. Enumerate major values of biodiversity. Explain with examples.
3. What are the threats to biodiversity. Write short notes on endemic species of India? Explain its significance
4. Discuss biodiversity conservation. Describe Ex-situ conservation and In-situ conservation in detail.
5. Describe different types of biodiversity conservation with examples.
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