Rajasthan Board RBSE Class 11 Physical Geography Chapter 21 Bio-diversity
RBSE Class 11 Physical Geography Chapter 21 Text Book Questions
RBSE Class 11 Physical Geography Chapter 21 Multiple Choice Questions
Question 1.
In which country is the highest bio – diversity found in the world?
(a) Brazil
(b) India
(c) South Africa
(d) Germany
Answer:
(a) Brazil
Question 2.
Which trees are commonly used for making ‘Vandanvaar’?
(a) Ashok and Peepal
(b) Mango and Jamun
(c) Ashok and Mango
(d) Banyan and Peepal
Answer:
(c) Ashok and Mango
Question 3.
In which region is maximum bio – diversity found?
(a) Wet region
(b) Coral reefs
(c) Mangrove Ecosystem
(d) Tropical ecosystem
Answer:
(b) Coral reefs
Question 4.
Ranthambore National Park is located in:
(a) Bharatpur
(b) Alwar
(c) Jaipur
(d) Sawai Madhopur
Answer:
(d) Sawai Madhopur
Question 5.
State Tree of Rajasthan is:
(a) Dhonk
(b) Khejri
(c) Tamarind
(d) Kadamb
Answer:
(b) Khejri
RBSE Class 11 Physical Geography Chapter 21 Very Short Answer Type Questions
Question 1.
Define Bio – diversity.
Answer:
The number of species of living organisms and plants available in any natural region is called bio – diversity.
Question 2.
Mainly, the density of which factor increases bio – diversity ?
Answer:
Mainly the concentration of forests increases bio – diversity.
Question 8.
What is the basis for developing the concept of bio – diversity?
Answer:
The Concept of bio – diversity has evolved in the past years due to environmental degradation.
Question 9.
From what is the medicine named as quinine obtained?
Answer:
The medicine named quinine is obtained from the bark of cinchona tree.
Question 10.
What is the meaning of ecotourism?
Answer:
Seeing wild animals living in their natural habitat in an independent and fearless way is called eco – tourism seeing and experiencing different native surroundings is also included in this.
RBSE Class 11 Physical Geography Chapter 21 Short Answer Type Questions
Question 1.
Comment on the food value of bio – diversity.
Answer:
According to the famous ecologist Norman Myers, about 80,000 species of plants and animals are consumed by humans as food. The entire food procurement of the world is mainly dependent on wheat, rice, maize, barley, sorghum , bajra, soyabean, beetroot, tur, coconut, potato, cassava, chick peas, fieldbeans, sugarcane etc.
Apart from these, various types of fruits like banana, mango, papaya, grapes, apples, oranges, watermelons, melons etc. and various typeset vegetables, like – brinjal, ladies finger, cabbage, tomato, etc. and various types of fish and marine creatures play a major role in the world’s food supply. Apart from these, ginger, black pepper, turmeric, saffron, coriander, asafoetida, fennel seeds, cumin, oregano, bay leaf, etc. are also used in domestic and commercial form.
Question 2.
Illustrate the social value of flora.
Answer:
The social value of flora can be explained by the conditions found in the society. Humans are social beings and diversity of life reflects the social values in various forms. For example: basil, banana, peepal etc. are such plants which are integral part of every religious celebration held in our homes. Ashok is the common tree whose leaves are essentially placed during the ‘Vandanwar’ yagna, marriage, religious rituals. This type of attitude of a person, of course, keeps the vegetation estate of nature safe. Thus, social value of vegetation is important.
Question 3.
What is the significance of the genetic pool in the field of agriculture?
Answer:
The genetic pool has special significance in the field of agriculture, because the food problems of the future can be easily resolved through them. Advanced varieties of food crops, beverage crops and pulse crops can be cultivated through the gene pool by which more production can be obtained in lesser area. The genetic pool is prepared by processing the seeds so that they can withstand adverse hydro – logical conditions.
Question 4.
Write the definition of bio – diversity according to Johnson (1993).
Answer:
Johnson, a scholar, defined bio – diversity (Convention on Biological Diversity) in 1993 thus Biological variations are found in the land, sea and aquatic (ecological) ecosystems. This differentiation may occur in the sub species of a species among the species and in the species of the ecosystem.
Question 5.
Write a brief comment on the medicinal value of bio – diversity.
Answer:
Various medicines are obtained in the form of bio – diversity. These different types of medicines are obtained from living beings and vegetation. Anti – cancer drugs, such as winnablastin and wincristine are produced from the plants of the Madagascar – Perivic or evergreen plant. These drugs have been successful in controlling 99% of blood cancer (leukemia) in childhood. Penicillin is obtained from fungus, and a drug named Quinine is prepared from the bark of the Cinchona tree. Similarly, antimicrobial drugs called erythromycin, tetracycline are prepared from bacteria. All these examples reveal the medicinal value of bio – diversity.
RBSE Class 11 Physical Geography Chapter 21 Essay Type Questions
Question 1.
Define Bio – diversity. Summarize the concept of bio – diversity in brief.
Answer:
The number of species of living organisms and plants available in any natural region is called bio – diversity. The word bio – diversity was first used by American entomologist E. A. Wilson in 1986, which was later adopted by other scientists and environmentalists in the form of a concept.
There are countless organisms present on the earth, in which genetic, ethnic and ecological diversity is found. Biological diversity is defined differently by different people. Different types of variations found in living beings are the result of biological evolution in millions of years. All the biospheres are evolved and controlled through these variations. This variation in animal and plant species scientific is called bio – diversity in language. Some scholars have written that the basis of human life on the earthly, homestead ship is the bio – diversity.
Concept / Theory of Bio – diversity:
The body of each organism is made of its genes, and the functioning of its body is also controlled by these genes. Gene is the fundamental basis of the bio – diversity of the biosphere. Concept / theory of bio – diversity has developed in the past years due to environmental degradation. Biological diversity and prosperity is one of the most important qualities of nature, which is the result of the process of development on the earth and which requires sustained protection.
Due to the unimaginable destruction of natural habitats, there has been a crisis of declining bio – diversity over the past years. For example, the hunting of Krishna (black) deer in our province of Rajasthan, hunting of around half a dozen elephants in the world famous Jim Corbett National Park, the death of 13 tigers in due to a disease called Triapinasymiosis, in Nandan Kanan reserve, etc. Such unbearable events strongly support this reality that even in our country, the bio – diversity sphere has not remained untouched by the imminent crises.
The survival of bio – diversity is very important for the sustenance of human life. The origin of pollution is the product of human activities. The graph of bio – diversity is definitely decreasing due to pollution which continues to be progressively increasing. So far, humans have ended the entire existence of about one million animal species and about 76% of wild animals, for their own benefit.
The decrease in bio – diversity is an important problem in the current world. Its deficiency affects the evolutionary capacity of living organisms and they find themselves helpless to adapt to environmental changes.
In the concept of bio – diversity, the species have a decisive position. In nature, it is said to be a kind of productive life and the same type of living creature as the productive descendant of a lineage growth. In nature, species join and give rise to new ones through evolution. Thus, bio – diversity is a very important condition for sustainability of life and longevity and sustenance of the environment.
Question 2.
Write a detailed note on the value of bio – diversity.
Answer:
The animals and plants present in nature are beneficial in many ways for human survival and progress. Our intellectual, religious and cultural diversity is also a part of bio – diversity. The economic process of state, nation and the world depends only on natural resources. The value of bio – diversity has been described mainly in the following points:
1. Food Value:
A large variety of food items are obtained from bio – diversity. These meet the food requirements in the world. These mainly include food grains like wheat, rice, maize, barley, sorghum, millet, soyabean, beetroot, tur, coconut, potato, cassava, sweet potato, chick peas, field beans and sugarcane, banana, mango, cilantro, papaya, grapes, apples, orange, watermelon, melon in the form of fruits and vegetables like brinjal, cucumber, cauliflower, tomato and ginger, turmeric, coriander, asafoetida, fennel seeds etc. They all reflect the food value of bio – diversity.
2. Medicinal value:
Different types of medicines are obtained from animals and plants. In which Madagascar perivial or evergreen plants are used to obtain life-saving medicines such as Winnablastin and Wincristine, and penicillin, tetracycline, etc. are obtained from fungus.
3. Beauty value:
Bio – diversity is beautiful. The more the diversity in nature the more beautiful it is. Increased bio – diversity attracts the visitors at large. Natural beauty has a very important role in the development of tourism. The colours and fragrance in the flowers naturally depict the value of beauty.
4. Genetic value:
Many genes are found in living organisms. In any group there are representative genes related to the species. In the field of agriculture, the genetic pool is also important because the food problems of the future can be successfully resolved through them.
5. Ethical value:
Indian society has always been the forerunner of preserving trees by worshiping them from ancient times. Our society, religion and civilization have made us morally strong. In our country, worship of Kadamb, Mango, Tamarind, Dhak and Mahua in the form of bio – diversity reflects our ethical attitude.
6. Social value:
The social value of bio – diversity has been a part of human life since the ancient past. Humans are social creatures and the diversity of life reflects the social values in various forms. Basil, banana, peepal etc. are plants which have a specific place as they are associated with our social traditions.
Question 3.
“Bio – diver sity provided by nature is a boon for humans”. Explain.
Answer:
Nature – provided bio – diversity is highly useful for humans. For this reason, it is considered a boon for humans. The gift of nature has been clarified in the following points:
- The entire biosphere is evolved and controlled by natural bio – diversity.
- bio – diversity is an important process for sustenance of life and long-term durability of the environment.
- Man has been dependent on biodiversity from ancient times to the present period, directly and indirectly. This includes elements such as food, clothes, shelter, etc.
- Our intellectual, religious and cultural diversity is also the result of bio – diversity.
- Natural resources also determine the economic system of the state, nation and the world.
- Different types of food items, fruits and vegetables are the result of biodiversity by which our daily needs are complete.
- Various types of medicines are made available to us by living beings and vegetation.
- The social value of bio – diversity has been a part of human life since ages.
- Biological diversity reflects social values in various forms.
- From our biological diversity, our society, religion and civilization have got a strong structure.
- Biodiversity gives us beauty. It also provides us entertainment.
- Natural beauty has an important role in the spread of tourism.
- Ecotourism and modern tourism are possible only due to bio – diversity.
- The variety of genes found in living beings is very useful for us.
From all the above points, it becomes evident that bio – diversity is highly useful to humans. For this reason, it is considered a boon for humans.
RBSE Class 11 Physical Geography Chapter 21 Other Important Questions
RBSE Class 11 Physical Geography Chapter 21 Multiple Choice Questions
Question 1.
What is mainaly included in the structure of the biosphere?
(a) Iroposphere
(b) Emacination sphere
(c) Lithosphere
(d) Exosphere
Answer:
(c) Lithosphere
Question 2.
From where do the creatures obtain nutrition on the lithosphere?
(a) From air
(b) from heat
(c) From water
(d) from soil
Answer:
(d) from soil
Question 3.
Water is present on how much part of the earth?
(a) 50.8%
(b) 69.6%
(c) 70.8%
(d) 87.6%
Answer:
(c) 70.8%
Question 4.
The lowest layer of the atmosphere is:
(a) Troposphere
(b) Stratosphere
(c) Ionosphere
(d) Exosphere
Answer:
(a) Troposphere
Question 5.
The amount of nitrogen in the atmosphere is:
(a) 21 per cent
(b) 78 per cent
(c) 9 per cent
(d) 0.03 per cent
Answer:
(b) 78 per cent
Question 6.
Who was the first to use the term bio – diversity?
(a) Odam
(b) Hakal
(c) Wilson
(d) Rauland
Answer:
(c) Wilson
Question 7.
How many hot spots are there in the world and India respectively?
(a) 30 and 6
(b) 25 and 2
(c) 22 and 3
(d) 35 and 7
Answer:
(b) 25 and 2
Question 8.
How many national parks have been established in Rajasthan?
(a) 2
(b) 3
(c) 4
(d) 6
Answer:
(c) 4
Question 9.
Where is the Gajner National Park situated?
(a) in Jaipur
(b) in Jodhpur
(c) in Udaipur
(d) in Bikaner
Answer:
(d) in Bikaner
Question 10.
Where was the Earth summit -2 held?
(a) in Kathmandu
(b) in Rio – de – Janeiro
(c) in Johannesburg
(d) in Paris
Answer:
(c) in Johannesburg
Matching Type Questions
Question A.
Match column A with column B:
| Column A (Name of the National Park) | Column B (District) |
| (i) National desert Park | (a) Churu |
| (ii) TalchhaDar | (b) Ajmer |
| (iii) Ravali Toderarh | (c) Karauli |
| (iv) Kailadevi | (d) Jaipur |
| (v) Nahargarh | (e) Kota |
| (vi) Chambal | (f) Jaisalmer |
Answers:
- (f)
- (a)
- (b)
- (c)
- (d)
- (e)
Question B.
Match column A with column B:
| Column A (Condition) | Column B (Related value) |
| (i) Sweet potato | (a) Ethical value |
| (ii) Evergreen plants | (b) Beauty value |
| (iii) Zoo | (c) Social value |
| (iv) Vandanavar | (d) Genetic value |
| (v) Genetic pool | (e) Food value |
| (vi) Worship of trees | (f) Medicinal value |
Answers:
- (e)
- (f)
- (b)
- (c)
- (d)
- (a)
RBSE Class 11 Physical Geography Chapter 21 Very Short Answer Type Questions
Question 1.
In what forms is bio – diversity visible on the earth?
Answer:
bio – diversity is visible on the earth in the form of micro-protozoans to giant whales and in the form of micro – lichens to large-sized trees.
Question 2.
What is biosphere the result of ?
Answer:
The biosphere is the result of the complex activities of biotic and abiotic components found on the surface of the earth.
Question 3.
How many types of adaptations are there in the organisms?
Answer:
There are mainly two types of adaptations in organisms:
- Hereditary adaptation.
- Acquired adaptation.
Question 4.
What is the difference between hereditary and acquired adaptation?
Answer:
Hereditary adaptation is obtained from birth, whereas the acquired adaptation is generated from the response of organism to any particular stimulus.
Question 5.
What has been included in the structure of the biosphere?
Answer:
In the structure of the biosphere, lithosphere, hydrosphere and atmosphere are mainly included.
Question 6.
What is meant by hydrosphere?
Answer:
The part of the earth’s surface which is covered with water is called hydrosphere.
Question 7.
What does genetic diversity mean?
Answer:
The properties of each organism are determined by genes at the genetic level. An estimate of the different forms of the same genes in any species of organisms is called genetic diversity.
Question 8.
What is the meaning of ethnic diversity?
Answer:
Details of the number of organisms of different species available in an ecosystem is called ethnic diversity.
Question 9.
What is ecological diversity?
Answer:
The complexity of the bio – species available in an ecosystem is called ecological diversity.
Question 10.
Why is variation present in the climate of India?
Answer:
Due to geographical disparities in India:
In the north, due to the Himalayan mountains, great ocean in the south, wet area in the east and arid zone in the west, the climate is different in India.
Question 11.
How many plant and animal species are found in India?
Answer:
There are about 46,000 plant species and 81,000 animal species are found in India.
Question 12.
When was the bio – diversity Bill passed?
Answer:
The bio – diversity Bill was passed in the Lok Sabha on December 2, 2002, and in the Rajya Sabha on December 11, 2002.
Question 13.
What is the main objective of the bio – diversity Bill?
Answer:
The main objective of this bill is to protect India’s vast bio – diversity, prevent foreign organisations and people from one – sided use and stop Bio – smuggling.
Question 14.
In which states is the Western Ghats hot spot spread in India?
Answer:
This hot spot of India is spread across Maharashtra, Karnataka, Tamil Nadu and Kerala states.
Question 15.
What are the natural causes for bio – diversity depletion?
Answer:
Growth in global temperature, climate change, thinning of ozone layer and acid rain are the natural causes for bio – diversity depletion.
Question 16.
What does the conservation of bio – diversity mean?
Answer:
Proper management of preserving bio – diversity and natural resources, to check the continuous decline in bio – diversity while keeping human interest in mind, is called the conservation of bio – diversity.
Question 17.
What steps have been taken to protect (conserve) wildlife in Rajasthan?
Answer:
Four National parks, 26 sanctuaries, 35 prohibition areas and 5 zoos have been set up in Rajasthan for the conservation of wildlife.
Question 18.
Where is the highest and lowest bio – diversity found in the world?
Answer:
The highest bio – diversity in the world is found in equatorial region on both sides of the equator and the lowest bio – diversity is found on the poles.
Question 19.
Where and when were the Earth Summits organised?
Answer:
The first Earth Summit was organised in Rio – de – Janeiro, Brazil and the Second Earth Summit was organised in 1992 in the city of Johannesburg, South Africa, in 1992.
Question 20.
More bio – diversity is found in which ecosystems in the world?
Answer:
The highest bio – diversity in the world is found in coral reefs, wet regions, mangrove ecosystems and tropical ecosystems.
Question 21.
What is meant by species ?
Answer:
In nature, the same type of organisms, worthy of productive life and reproduction are called species.
Question 22.
What does Genetic pool mean?
Answer:
Connecting of the genes of the organisms of any species shows the position of the genetic fund.
Question 23.
How can the bio – diversity of organisms be preserved?
Answer:
Genetic pool and the collection of genes of the organisms of various species.
RBSE Class 11 Physical Geography Chapter 21 Short Answer type Questions (SA-I)
Question 1.
Explain the nature of the lithosphere.
Answer:
The lithosphere is the solid part of the Earth, which is spread over almost 29.2 per cent of the entire earth in the form of continents and islands. Its upper surface is made of unorganized soil, under which rocks are found. But the upper surface of the earth is important in terms of the biosphere. Because all creatures receive nutrition only from soil present in the lithosphere.
Question 2.
Explain the term genetic diversity.
Answer:
The properties of each organism are determined by genes at genetic level. Assessment of different forms of the same genes in any species of organisms is called genetic diversity. If the genetic diversity is more, a species will be able to adapt itself to environmental changes. On the contrary, if the genetic diversity is low, then that species will be prone to extinction because the species will fail to adapt themselves according to the environmental changes. Various plant species are born by genetic diversity.
Question 3.
What are the responsible factors for the degradation of bio – diversity?
Answer:
Two types of factors are responsible for the degradation of bio – diversity:
- human factors.
- natural factors.
At present, the destruction of natural habitats of animals, hunting, increasing pollution as a result of human economic activities are the human causes of bio – diversity degradation, whereas there are natural factors also such as increase in global temperature, climate change, thinning of ozone layer and acid rain, etc.
Question 4.
Which types of improvements have been done in the habitats of organisms in India?
Answer:
In order to improve the habitat of living organisms in India, many biosphere reserve areas have been set up, in which Nilgiri, Nandadevi, Nokrek, Great Nicobar, Gulf of Mannar, Manas, Sunderban, Simlipal, Pachmarhi, Kanchenjunga, Agasthyamalai, Panna, Achankaram – Amarkantak, Seshachalam Namdapha, Uttarakhand, Thar Desert, Smaller Rann of Kutch, Kanha, Kaziranga and Northern Andaman Biosphere reserve area are included.
Question 5.
Write the names of the major National Sanctuaries / National Parks of Rajasthan.
Answer:
The major wildlife and bird sanctuaries of Rajasthan mainly include Rajiv Gandhi National Park Ranthambore (Sawai Madhopur), Keoladeo Ghana National Bird sanctuary (Bharatpur), National Desert park (Jaisalmer) and Sariska Wildlife National Park (Alwar). In addition to these National Parks, major sanctuaries include Darrah Sanctuary (Jhalawar), Talchapar Sanctuary (Churu), Nahargarh (Jaipur), Jaisamand (Udaipur), Kumbhalgarh (Pali), Bandh Baretha (Bharatpur), Van Vihar (Dholpur), Sitamata (Chittorgarh), Mount Abu (Sirohi), Raoli Todgarh (Ajmer), Chambal (Kota), Jawahar Sagar (Kota), Jamua Ramgarh (Jaipur), Kailadevi (Karauli) and Gajner Sanctuary (Bikaner).
RBSE Class 11 Physical Geography Chapter 21 Short Answer Type Questions (SA-II)
Question 1.
Demonstrate the organisation and distribution of gases found in the atmosphere.
Answer:
The highest amount of atmospheric gases constitute nitrogen (78%) and oxygen (21%), the remaining 1% other gases are carbon dioxide, neon, argon, ozone, etc. Various tests have shown that in the troposphere the proportion of atmospheric gases varies to a height of 50 kilometers. Heavy and dense gases such as carbon dioxide can reach only up to 20 km, and oxygen and nitrogen gases also become extinct after the height of 140 km. After the height of 150 km, only hydrogen is found in the form of a major gas.
Oxygen, i.e. Oxygen is the most essential gas for respiration of all organisms, while carbon-dioxide is the most essential gas for photosynthesis in plants. Similarly, nitrogen is an important component in all organisms, which they get from food.
Question 2.
Describe the hot spots found in India.
Answer:
Such parts of the world where abundant plant and animal species, which are not found in any other area are present, are called hot spots.
India’s hot spots:
So far, 25 hot spots have been identified in the entire world, two of them are in India which are described as following:
- Western Ghats.
- Eastern Himalayas.
1. Western Ghats:
The expanse of this hot spot is found in the states of Maharashtra, Karnataka, Tamil Nadu and Kerala in about 1600 sq. km area, along the western coast of the country. It is , only 5 per cent of the total land area of the country, but here 25 percent of the plant species of the country are found. There are two centers in terms of bio – diversity:
- Amambalam Reserve
- Agasthamalai Mountains
2. East Himalayan region:
Temperate forests are extensively extending from 1700 to 3500 meters height, in which 11540 plant species are located. Of these, 4052 are local species.
Question 3.
Explain the threats of bio – diversity.
Answer:
Various species have become extinct from time immemorial, and due to genetic diversity, new species keep evolving according to the changing environment. But in the last century, through human, scientific and technological advancements, bio – diversity has been greatly degraded due to human exploitation of the nature at the highest level to elevate his standard of living.
As a result, the natural extinction rate of different species has increased from one species per decade to 100 species per decade in various ecosystems. If this rate of extinction continues to grow like this then many species of plants and organisms will become extinct in the near future. Therefore, due to human impact, the surviving species at present are at risk of extinction.
At present, the destruction of natural habitats of animals and their hunting, increasing pollution as a result of human economic activity, is the main human reason for the decline of bio – diversity. As a result of some other natural causes, the decline in bio – diversity has increased. In these natural factors, global warming, climate change, thinning of ozone layer, acid rain, etc. are the major ones.
RBSE Class 11 Physical Geography Chapter 21 Essay Type Questions
Question 1.
What is meant by biosphere? Explain its structure.
Answer:
Biosphere is the habitat of living organisms in which the organisms living in lithosphere, hydrosphere and organisms living in the atmosphere, their mutual interactions and relationships are included.
Structure of the biosphere:
The lithosphere, hydrosphere and atmosphere are included in the structure of the biosphere. The description of these organs of the biosphere is as follows:
1. Lithosphere:
The lithosphere is the solid part of the Earth, which is spread in about 29.2 percent of the entire Earth in the form of continents and islands. Its upper surface is made of unorganized soil, under which rocks are found. But the upper surface of the Earth’s surface is important, because all the organisms receive nutrition only from the soil obtained on the lithosphere.
2. Hydrosphere:
Ocean is present at over 70.8 per cent of the entire Earth. If rivers, ponds and other aquatic sources are also included in it, then about 72 per cent of the Earth’s surface is covered with water, which is called hydrosphere. Water is the second most important requirement of the organisms after oxygen, so water has been called life. The human body’s requirement of oxygen and hydrogen is met by the availability of water.
According to an estimate, about 1360 million cubic km. of water is available on the Earth’s surface, out of which 97 per cent i.e., 1320 million cubic km is located in the oceans, approximately 30 million cubic km. of water is located in the form of ice and less than 1 per cent is available in the form of underground water. The water available on the surface of the Earth is converted into a cyclic flow and then it falls on Earth in the form of rainfall by the process of condensation.
3. Atmosphere:
An envelope of gaseous mixture is found surrounding the earth’s surface, which is called the atmosphere. This part stretches from the surface of the Earth to the height of thousands of kilometers. There are many types of gases, water vapor and dust particles mixed in it. The combination of these elements is not universally found, but it varies with varying height, latitude, weather, etc.
The lowest percentage of the atmosphere is found in the troposphere, except the water vapor and dust particles, and the average percentage of other gases is found almost everywhere, because the flowing nature of winds, air pressure and temperature keeps their proportion constant.
Question 2.
Define bio – diversity and describe its types.
Answer:
The number of species of living organisms and plants available in any natural region is called bio – diversity. The term bio – diversity was first used by American entomologist E.O. Wilson in the year 1986.
Format of bio – diversity:
On Earth, countless organisms are found. Based on the variations found in these organisms, the following formats of bio – diversity are seen:
- Genetic diversity.
- Ethnic diversity.
- Ecological diversity.
All these forms of bio – diversity are described as follows:
1. Genetic diversity:
The properties of each organism are determined by genes at the genetic level. Presence of different forms of the same genes in any species of organisms is called genetic diversity. A species will be able to adapt itself to environmental changes if sufficient genetic diversity is present. On the contrary, if the genetic diversity is less, than species will be prone to extinction, because such species will fail to adapt itself to the environmental changes. Various species are born by genetic diversity in plants and animals.
2. Ethnic diversity:
The description of the number of organisms of different species available in an ecosystem is called ethnic diversity.
3. Ecological diversity:
The complexity of bio – diversity available in an ecosystem is called ecological diversity. Ecological diversity involves the processes of circulating energy from one nutritional level to another nutritional level, synchronized food traps and mineral substances. Diverse bio – diversity is found in the saline aquatic system of the sea as well as different aquatic systems. In saline water, large animals like whales, sharks are found, while there are no such creatures in the non – saline water. Similarly, there are different types of plants and wild animals found in forests, grasslands and deserts.
Question 3.
What measures are needed to be adopted for the prevention of rapid decline in bio – diversity?
Answer:
It is necessary to adopt the following measures for the prevention of decline of bio – diversity:
1. Artificial collection:
The protection of such species is included under artificial collection, which are at an increased risk of extinction. Such species can be easily preserved in the same areas, where they are on the verge of extinction.
2. Improvement in natural habitats:
Mankind has either destroyed or distorted the natural habitats of the animals for its own advancement and prosperity. Improvement of such deformed or destroyed natural habitats of organisms is necessary to provide food and other essentials to the species living in them. So far, 18 biosphere reserve areas have been set up in India.
These are the Nilgiri, Nanda Devi, Nokrek, Great Nicobar, Mannar Bay, Manas, Sunderban, Simlipal, Pachmarhi, Kanchenjunga, Agasthamalai, Panna, Achankamar – Amarkantak, Seshachalam Namdapha, Uttarakhand, Thar Desert, Little Rann of Kutch, Kanha, Kaziranga, North Andaman, etc. Out of these 18 reserved biospheres, nine (09) – Nilgiri, Sunderban, Gulf of Mannar, Nandadevi, Great Nicobar, Simlipal, Pachmarchi and Achankamar-Amarkantak have been recognised by UNESCO.
3. Ban on Hunting:
Hunting can be allowed in those biological regions where there is excess of wildlife, and high fertility rates are there.While hunting should be strictly prohibited in all the other sensitive areas.
4. Wild life Conservation Act:
International nature and natural resource conservation organisation has asked all the nations of the world to develop such an effective system of environmental protection rules, so that human rights can remain safe and at the same time it does not harm the future generations.
Our country is one of the few select countries where Forest Policy is applicable since 1894. This forest policy was amended in 1952 and 1988. The main basis of the Revised Forest Policy, 1988, is the protection, conservation and development of forests.
Not only this a major plan has been prepared under the National Wild life Programe for the next 20 years, aimed at preventing deforestation and covering one – third of the country with trees / forests. Similarly, the National Wild life Workshop, 1993 has been modified to form a new Wild life Action Plan (2000 – 2016) under which programmes for wild life conservation and conservation of extinct species are made.
5. Establishment of National Parks and Sanctuaries:
In our country, so far, 89 national parks and 490 protected reserves have been established, which are spread over a. total area of about 150,000 square km. of the total area of the country. Their main objective is to preserve wild life, prevent hunting of wild animals and illegal trade of wild life products, and to promote ecological development in the adjoining areas of national parks and sanctuaries.