Saturday 30 January 2021

Chapter 15 Biodversity and Conservation

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 15-BIODIVERSITY AND CONSERVATION 

CHAPTER NO.15 BOIDIVERSITY AND CONSERVATION

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INTRODUCTION


BIODIVERSITY

Biodiversity describes the richness and variety of life on earth.It is the most complex and important feature of our planet. Without biodiversity, life would not sustain.

The term biodiversity was coined in 1985. It is important in natural as well as artificial ecosystems. It deals with nature’s variety, the biosphere. It refers to variability among plants, animals and microorganism species.

 


Biodiversity includes the number of different organisms and their relative frequencies in an ecosystem. It also reflects the

organization of organisms at different levels.

 

Biodiversity holds ecological and economic significance. it provides us with nourishment, housing, fuel, clothing and several other resources. It also extracts monetary benefits through tourism.

Therefore, it is very important to have a good knowledge of biodiversity for a sustainable livelihood.

 

Levels of biodiversity

Biodiversity is usually explored at three levels —

GENETIC DIVERSITY,

SPECIES DIVERSITY and

ECOSYSTEM DIVERSITY.

 

These three levels work together to create the complexity of life on Earth.

 


Genetic diversity is the variety of genes within a species.Each species is made up of individuals that have their own particular genetic composition. This means a species may

have different populations, each having different genetic compositions. To conserve genetic diversity, different populations of a species must be conserved. Genes are the

basic units of all life on Earth. They are responsible for both the similarities and the differences between organisms.



Species diversity is the variety of species within a habitat or a region. Some habitats, such as rainforests and coral reefs,have many species. Others, such as salt flats or a polluted stream, have fewer.

 

In Australia, more than 80% of plant and animal species are endemic, which means that they only occur naturally in Australia.

 

Species are grouped together into families according to shared characteristics. In Australia, it is not just the individual species that are endemic - whole families of animals and plants are endemic. Seven families of mammals, four of birds and tweive

of flowering plants are endemic to Australia. No other country has as many endemic flowering plant families as Australia of these are insects. Invertebrates include crabs, snails, worms,corals and sea stars.



An ecosystem is a community plus the physical environment that it occupies at a given time. An ecosystem can exist at any scale, for

example, from the size of a small tide pool up to the size of the entire biosphere. However, lakes, marshes, and forest stands represent more typical examples of the areas that are compared in discussions of ecosystem diversity.

 

Broadly speaking, the diversity of an ecosystem is dependent on the physical characteristics of the environment, the diversity of species present, and the interactions that the species have with each other and with the environment. Therefore, the functional complexity of an ecosystem can be expected to increase with the number and taxonomic diversity of the species present, and the vertical and horizontal complexity of the physical environment. However, one should note that some ecosystems (such as submarine black smokers, or hot springs)that do not appear to be physically complex, and that are not especially rich in species, may be considered to be functionally complex. This is because they include species that have remarkable biochemical specializations for surviving in the harsh environment and obtaining their energy from inorganic chemical sources (e.g., see discussions of

Rothschild and Mancinelli, 2001).

 

“Let us know what we have learnt!”

PART: A VERY SHORT ANSWER TYPE QUESTIONS:

A. MCQs:

 

1. Which one has maximum genetic diversity in India?

a. Maize

b. Mango

c. Ground nut

d. Rice

 

2. Which of the following countries has the highest biodiversity?

a. Brazil

b. South Africa

c. Russia

d. India

 

3. Which of the following group of plants exhibit more species diversity?

a. Angiosperms

b. Algae

c. Bryophytes

d. Fungi

 

4. Among the ecosystem mentioned below, where one can find maximum biodiversity?

a. Mangroves

b. Desert

c. Coral leaves

d. Alphine meadow

 

B. TRUE/FALSE:

1. Lower diversity leads to uniformity in the species.

2. India has low ecosystem diversity.

3. Most species rich area is Amazonian rainforest in South America.

 

C. FILL UPs:

1. Within -community diversity is called__

2. Between- community diversity is called__ st.

3. Number of species per unit areais called__

 

PART - A

A. MCQS:

 

(d) Rice

(a) Brazil

(d) Fungi

(c) Coral leaves

 

B. TRUE/FALSE:

1. True

2. False

3. True

 

C. FILL UPs:

1. Alpha diversity

2. Beta diversity

3. Species richness

 

PART: B SHORT ANSWER TYPE QUESTIONS:

1. Explain Biodiversity.

2. Write a note on gradients of biodiversity.

3. Difference between genetic diversity and species diversity?

 

PART C: LONG ANSWER TYPE QUESTIONS:

1. Explain levels or components of biodiversity.

 

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INTRODUCTION

GRADIENTS OF BIODIVERSITY:Students, the distribution of richness of species of animals and plants is not same all over the globe. The changes in patterns of Biodiversity over different regions of the globe are called the gradients of Biodiversity.

 

Change in latitude or altitude leads to change in Biodiversity .It is called

latitudinal gradient.

 

Biodiversity increases from poles to equators (from high to low altitude) or we

can say that richness in Biodiversity decreases as we go from equatorial region to

polar region. Number of species increase in area with favorable environmental

conditions (e.g. in tropical rainforests). In temperate regions, plant grows for

shorter period due to adverse climatic conditions.

 

For example vascular plants in Tropic Rainforests are 118-236 per 0.1

hectare sample area when compared with temperate zones (only 21-48 species). It

has been found to be true with other taxonomic groups like ants, birds, butterflies,etc. can be noticed.

 

Also Change in altitude leads to change in biodiversity. It is called altitudinal

gradient. On mountains, decrease in species diversity takes place from lower to

higher altitude. Higher seasonal variations and fall in temperature leads to

reduction in biodiversity. With1000 m increase in altitude leads to temperature drop of about 6.5 degree Celsius.

 

So Biodiversity gradient exist according to change in latitude or altitude.HOTS POTS OF BIODIVERSITY;Hot spots are Bio geographical areas that are extremely rich in species with

high endemism (species confined to a particular region), and are under constant threat.Concepts of hot spots of biodiversity were developed by Norman Myers in 1988.

He identified 34 hot spots of biodiversity till date. India contributes about 8 percent

of global biodiversity, although it bears only 2.4 per cent of land area of world.

These areas are particularly rich in floral wealth and endemism, not only in

flowering plants but also in reptiles, amphibians, butterflies and some mammals.


CRITERIA FOR IDENTIFYING THE HOT SPOTS ARE:

1) Number of endemic species: It must contain at least 1500 species of vascular plants as endemics.

 

2) Degree of threat: It has to have lost at least 70% of its primary vegetation.

Number of hot spots identified are 25 (Till 2000). Few important are:Brazil's cerrado, Central Chile, California, floristic province, coastal forest of Tanzania, West African forest, Indo- Burma, South Central China etc.Out of 25, 15 are reported in Tropical Forest.About 20 percent of human population is inhabited in hot spots area.

Out of 25 hot spots 2 are found in India.

They are:

 

1) Eastern Himalayan Hot spot: It has temperate forests. It is rich in endemic

plant species. It has primitive angiosperms like Magnolia and Retula.

 

2) Western Ghat Hot spot: It has evergreen forests at 500m of sea level and semi evergreen forest between 500-1500m height.

 


LET US KNOW WHAT WE HAVE LEARNT!

PART: A- VERY SHORT ANSWER QUESTIONS:

A) MCQs:

 

Q1. Which of following habitats show the highest diversity of living species?

(a)Temperate Forest

(b) Grasslands

(C) Desert

(d) Tropical Rainforest

 

Q2.How many hotspots of Biodiversity have been identified till date by Normal Myers?

A) 18

B) 25

C) 34

D) 43

 

Q3. Which one is hotspot of Biodiversity?

A) Eastern Ghats

B) Western Ghats

C) Aravalli Hills

D) Shivalic Hills

 

Q4. Biodiversity gradient exist according to:

A) Latitude

B) Altitude

c) Longitude

D) BothA&B

 

Q5.Varierty of vascular plants in Tropical rainForests when compared with Temperate Zone is:

A)More

B)Less

C) Same

D) None of the Above

 

B) TRUE/FALSE TYPE QUESTIONS:

1. Hot spots are biogeographical areas that are extremely rich in species 

with high endemism, and are under constant threat .( True/False)

2. The number of hot spots had increased from 25 to 34. ( True/False)

3. Tropical Zone is winterless and very hot.(True/False)

 

C) FILL UP TYPE QUESTIONS:

1. Richness in Biodiversity ----—----as we go from equatorial region to polar region.

2. In India hot spots included Western Ghats and —----------—---

 

ANSWER KEY: PART -A

(A) MCQs:

 

1. d Tropical Rain Forest; there is no dry season in all months & has favorable

environmental conditions.

2.c 34

3. b Western Ghats; covers most of the deciduous and rain forests, known for

their high species richness.

4. d_ Both Latitude and Altitude

5.a More


(B) TRUE/FALSE:

1. True

2. True

3. True

 

(C) FILLIN THE BLANKS:

1) Decreases

2) Eastern Himalayas

 

PART: B - SHORT ANSWER TYPE QUESTIONS:

Q1. Define Hot spots of Biodiversity.

Q2. Name Hot spots of India. What kind of Biodiversity do they have?

Q3. What are the main criteria for determining Hotspots?

 

PART:C - LONG ANSWER TYPE QUESTIONS:

Q1. Explain Gradients of Biodiversity.

 

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INTRODUCTION

 

India is the seventh largest country in the world, with this 2.4% of the world’s

land area, India accounts for about 7-8% of recorded species of the world.

 

The varied edaphic, climate and topographic conditions and years of geographical stability have resulted in a wide range of ecosystems and habitats.

 

India is one of the 17 Mega Biodiversity Nation in the world. From about 70

% of the total geographical area surveyed by the Ministry of Environment and Forests in India, 45,500 plant species (including fungi and lower plants) and 91,000 animal species, representing about 7 % of the world’s flora and 6.5% of the world’s fauna respectively, have been described.

 

BIOGRAPHIC ZONES IN INDIA

BIOGRAPHIC is the study of distribution of species, organisms and ecosystems in

geographic space and through geological time.

India has very typical geology, terrain conditions, and topography, land use,

geographic and climate factors. Based on these factors, the country can be divided

into ten recognizable biogeographic zones.



 TRANS-HIMALAYAN REGION:It is a favourable habitat for the biggest populations of wild sheep and Goat (Bharal) in the world. The other rare fauna includes Snow Leopard and the Migratory Black-necked Crane (Grus nigricollis). The cold dry desert of this zone represents an extremely fragile ecosystem.

 

HIMALAYAN REGION:Himalayan Zone, in the far North is another Biogeographic zone. It covers about 6.4% of the total geographical area in India. It includes some of the highest peaks in the world. This zone makes India as one of the richest areas in terms of habitats and species. The Alpine and sub-alpine forests, grassy meadows and the moist

mixed deciduous forests provide diverse habitat for endangered species such

as:

Bharal (Pseudois nayaur)

Ibex (Capra ibex)

Markhor (Capfalconeri Jemlabicus)

 

INDIAN DESRT ZONE:The Indian Desert zone is another important biodiversity Zone. It covers about 6.6% of the total geographical area. It includes the Thar and Kutch deserts. It has large expanses of grassland that supports several endangered species of

mammals such as: Wolf (Canis lupus), Caracal (Felis caracal), Desert Cat (Felis

Libyca) and birds of conservation interest viz, Houbara Bustard (Chamydotis

undulate) and the Great Indian Bustard (Ardeotis nigriceps).

 


SEMI-ARID REGION:The Semi-arid biodiversity region in India covers about 16.6% of the total geographical area. It is a transition zone between the desert and dense forests of

western Ghats. Peninsular India has two large regions, which are climatically semi-arid. This semi-arid region also has several article and natural lakes and marshy

lands. The Dominant grass and palatable shrub layer in this Zone support the highest wildlife biomass.

 


THE WESTERN GHATS:The Western Ghats covers about 4% of the total geographical area. It is one of the major tropical Evergreen Forest regions in India. This zone represents one of the biodiversity ‘hot spots’ with some 15,000 species of higher plants, of which 4,000

(27%) are endemic to the region. The Western Ghats harbour Visible populations of most of the vertebrate species found in the peninsular India, besides an endemic faunal element of its own.

 

Significant species in this region: Nilgiri Langur (Presbytis Jobni). Lion Tailed

Macaque (Macaca silenus), Grizzled Gaint squirrel (Ratufa Macrouca) and

Malabar Givet (Viverricula megaspila).

 


DECAN PLATEAU:The Decan plateau covers about 42% of the total geographical area. It is a semi-arid region that fails in the rain shadow area of the Western Ghats. This

biographical zone of Peninsular India is by far the most extensive zone. These

include India’s finest forests particularly in the States of Madhya Pradesh,

Maharashtra and Orissa. Majority of the forests are deciduous in nature with

regions of the greater biological diversity in the hill ranges.It consists of deciduous forests, thorns forests and degraded Scrubland, all of which support Diverse wildlife species. Species such as: Chital (Axis axis), Sambar (Cervus unicolor), Nilgai( Boselpus tragocamelus) and Chousingha (tetracerus quadricornis) are abundant in this zone.

 


DESERT PLATEAU:Some other species like Barking deer (Muntiacus muntjak) and Gaur (Antilope cervicapra) are more frequent in, or are restricted to moister areas. They are still found in fairly large numbers. Species with small populations Include the Elephants

(Elephasmaximus) In Bihar-Orissa and Karnataka-Tamil Nadu belts, Wild Buffalo

(Bubalus bubalis) In a small area at the junction Of Orrisa, Madhya Pradesh and

Maharashtra and the hard ground Swamp Deer (Cervus duvauceli) Single locality

in Madhya Pradesh.

 


GANGETIC PLAIN:The Gangetic plain. It covers about 10.8% of the total geographical area in India. It is a flat alluvial region lying to the North and South of the Ganga River and its major tributaries and in the foothills of the Himalayas.

 

The characteristic fauna of this region include: Rhino (Rhinoceros unicornis),

Elephant (Elephas maximus), Buffalo (Bubalus bubalis).

 


COASTAL REGION:India has an extensive coastal belt. These constitute about 2.5% of the total geographical area. This belt includes very vast sandy beaches mangroves, mud

flats, coral reefs and marine angiosperm pastures.The coastal regions are also considered as the wealth and health zones of India.The coastline from Gujrat to Sunderbans is estimated to be 5,423 km long. A total

of 36 islands constitutes the Lakshadweep, which are of coral origin. However, the

densely populated Lakshadweep islands virtually have no natural vegetation.

 

NORTH-EAST REGION:The North-East Region covers about 5.2% Of the total geographical area, in India.It represents the transition zone between The Indian, Indo-Malayan and Indo-Chinese Bio-geographical regions as well as being a meeting point of the

Himalayan mountains and peninsular India.

The North-East is thus the biogeographical ‘gateway’ for much of India’s fauna and

flora. It is a major biodiversity hotspot. A diverse set of habitats coupled with long

 

term geological Stability has allowed the development of significant levels of

endemism in all animal plant groups.

 

ANDAMAN & NICOBAR ISLANDS:The Andaman and Nicobar Islands constitute about 0.3% of the total geographical area. They are one of the three tropical moist evergreen forests zones in India. The islands house an array of Flora and fauna which are not found elsewhere. Hence these islands are centres of high endemism. They support a wide diversity of

corals.Some of the endemic fauna of Andaman & Nicobar Islands include Narcoma

hornbill, South Andaman Krait etc.

 

LET US KNOW WHAT WE HAVE LEARNT!!

PART: A- VERY SHORT ANSWERS TYPE QUESTIONS:

(I) MULTIPLE CHOICE QUESTIONS:

 

1. How many Biogeographical Zones in India?

(a) 12

(b) 10

(c) 13

(4) 18

 

2. How many percent of species recorded in India?

(a) 7-8%

(b) 10-12%

(c) 16-18%

(d) 2-4%

 

3. How many numbers of animal species present in India?

(a) 81000

(b) 71000

(c) 91000

(d) None

 

4. How much area covered by Himalayan Region in India?

(a) 6.4%

(b) 7.4%

(c) 8.4

(d) 9.4%

 

5. Which area present in Decan Plateau?

(a) Punjab, Haryana

(b) Kamataka, Tamil Nadu

(c) Madhya Pradesh, Orissa

(d) All

 

(Il) FILL IN THE BLANKS:

(1) The Gangetic plain covers about ...........% of total geographical area in

India.

 

(2) The Semi-arid biodiversity region covers about........% of the total geographical area in India.

 

(3) The coastal Regions are considered as........ Zones of India.

 

(Ill) TRUE/FALSE:

(1) In Andaman and Nicobar Islands is present hornbill, Andaman krait.

(2) In Trans Himalayan Regions are present white sheep, Goats and Black head Crane.

 

ANSWER KEY: PART—A

 

1. (b) India has 10 biographical regions.

2. (a) Total percentage of species found in India is 7.8%.

3. (c) Total number of species found in India is 91000.

4. (a) Himalayan region covers 6.4% area In India.

5. (c) In Deccan plateau Madhya Pradesh, Maharashtra, Orissa states are present.

 

 

1. 10.8%

2. 16.6 %

3. health and wealth

 

1. True

2. True

 

PART: B - SHORT ANSWER TYPE QUESTIONS:

Q1. Write the example of birds of Indian Desert zones.

Q2. Explain Fauna and Flora of the Western Ghats.

 

PART: C - LONG ANSWER TYPE QUESTIONS:

Q1. Write a note on Geographical regions of India.

 

A175

 

INTRODUCTION

Biodiversity means variety and variability among living organisms at all levels

of biological organisation.According to the international union for conservation of nature and natural resources IUCN, the total number of plant and animal species described till now is slightly more than 1.5 million. Although India has only 2.4 % of world's

total land area but it shares 8.1 % of global species diversity.Biodiversity is very important to mankind. Now we will discuss some benefits of biodiversity.

 

USES/BENEFITS OF BIODIVERSITY

Due to following uses biodiversity is very important for mankind:

 

1. ROLE OF BIODIVERSITY IN ECOSYSTEM:

All the living organisms are closely interlinked with each other through food chain,food webs, material cycling, energy flow, etc. Destruction of one kind of wildlife may disturb the ecological balance in nature e.g., if all the snakes are destroyed then the population of rats will increase and destroy the crops. Biodiversity is required for maintaining and sustainable use of goods and services from ecosystems like maintenance of gaseous composition in atmosphere, pollination, formation of soil,

nutrient cycling, climate control by forests and oceanic systems.

 

2. FOOD:Biodiversity is very important as it provides food. Food is obtained from sources like livestock, forestry, plants and fish.

 


3. INDUSTRIAL IMPORTANCE:Wildlife is beneficial to us in many ways

(a) Fur, skin of animals, musk, leather, honey, pearis etc. obtained from wild

animals is good source of trade.

 

(b) Ivory of elephants, horns of rhino, antlers of deer etc. fetch large amount of

money in foreign market.

 

(c) We get several useful products like Timber, gums, resins, paper, tannins, dry

fruits, fibres, tea and coffee from wild plants.

 

4. AESTHETIC AND CULTURAL IMPORTANCE:

Biodiversity have great aesthetic value for us because of beautiful birds, colourful

butterflies, mammals and green forests. Aesthetic pleasure derived from biodiversity

includes pet keeping, bird watching, gardening, wild life sanctuaries etc.

Many plants are worshipped in India for example Peepal, Tulsi, Mango and Khejiri.

Many animals like birds and snakes are also worshipped.

 


5. ETRICAL NEEDS:Organic evolution started about 3.5 billion years ago and the present wildlife is the outcome of that organic evolution. So it becomes our ethical duty to preserve and conserve the wildlife for our upcoming generations.

 

6. RELIGIOUS IMPORTANCE:Biodiversity has religious importance too. Some animals are symbolised as the Vahanas of Hindu gods and goddesses for example mouse for Ganesh Ji, peacock for Subramaniam, tiger for Devi Durga, Garuda for lord Vishnu, etc.

 


7. SCIENTIFIC IMPORTANCE:Biodiversity is also very important for scientific reasons.

Wildlife is very important source of gene bank for breeding programmes in fisheries, animal husbandry, agriculture, etc. Many animals like frogs, rats, guinea pigs, rhesus monkey, rabbits, etc. are used as research materials for drug testing before applying to mankind. By genetic modifications in wild varieties plant breeders have produced a number of high yielding and disease resistant varieties. So there is a great need to preserve wildlife for getting new varieties.

 

8. DRUGS AND MEDICINES:Many plants or plant extracts are used as medicines. Some examples of drugs and medicines extracted from plants are given below:

 

Morphine: Obtained from Papaver somniferum is used as analgesic drug.

 

Taxol: It is anticancer drug extracted from bark of Taxus brevifolia.

Penicillin: It is widely used as antibiotic and is derived from a fungus called

Penicillium notatum.

 

Tetracyclin: It is obtained from bacteria

 

Digitalin: It is used to cure heart ailments is obtained from Digitalis.

 

Quinine: It is used for the treatment of malaria and is obtained from Cinchona

ledgeriana.

 

9. SPORTS AND ENJOYMENT:In circus shows some animals are used for recreation of people. National parks and sanctuaries give us thrilling experiences.Many benefits of wildlife is still not known to us. So conservation of non beneficial species is equally important.

 

LET US KNOW WHAT WE HAVE LEARNT!

PART: A-VERY SHORT ANSWER TYPE QUESTIONS:

A) MULTIPLE CHOICE QUESTIONS:

 

1. Importance of wildlife lies in:

a. Balancing the population

b. Maintenance of food chains and natural cycles

c. Usefulness in breeding programs

d. All of the above

 

2. Had Cinchona been eliminated before its use was discovered, man would have been deprived of:

a. Use ofits bark as dalchini

b. Tejpatta used as a spice

c. Antimalarial drug

d. Valuable timber

 

3. Destruction of species would be unethical because:

a. It is a product of long evolutionary history

b. It forms a part of rich biological diversity

c. It may still have certain unknown values

d. All of the above

 

4. Morphine is used as:

a. Analgesic drug

b. Anticancer drug

c. Antibiotic

d. To cure heart ailments

 

5. Percentage of global species diversity shared by India is:

a. 8.1%

b. 9.3%

c. 24%

d. 1.5%

 

(B) TRUE / FALSE:

1. Penicillin is obtained from Papaver somniferum.

2. Biodiversity don't have any religious importance.

 

(C) FILL IN THE BLANKS:

1. Organic evolution started about --—-----years ago

2. —-----— is obtained from Cinchona.

3. -------- means variety and variability among the living organisms.

 

ANSWER KEY: PART -A

(A) MCQ's:

 

1. (d) all of the above

2. (c) antimalarial drug (Quinine is obtained from Cinchona)

3. (d) all of the above

4. (a) analgesic drug (Morphine is derivative of Opium.It is very strong and

effective sedative and analgesic)

5. (a)8.1%

 

(B) TRUE/ FALSE:

1. False. (Penicillin is obtained from Penicillium notatum.)

2. False. (Some animals and birds are symbolised as vahanas of gods and

goddesses. )

 

(C) FILL IN THE BLANKS:

1. 3.5 Billion years ago

2. Quinine

3. Biodiversity

 

PART: B - SHORT ANSWER TYPE QUESTIONS:

Q1. Explain industrial importance of biodiversity.

Q2. State the uses of biodiversity in moder agriculture.

Q3. How morphine, taxol and quinine are important to us?

 

PART: C - LONG ANSWER TYPE QUESTION:

Q1. Give benefits of biodiversity.

 

A176

 

INTRODUCTION

Biodiversity refers to the variety and variability of all animals, plants and

microorganisms and the ecological complexes of which they are a part.The term biodiversity was coined by W. G Rosen in 1985.Biodiversity represents the totality of genes, species and ecosystems of a

region.Biodiversity is very useful because of its role in ecosystem, its scientific importance.We get food and many drugs and medicines from nature for example morphine,

taxol, penicillin, tetracycline etc.

There may be certain benefits which are still not known to us and may become known in future so the conservation of even non beneficial species is equally significant.

As we have seen that biodiversity is very important to us but due to unplanned

activities of man the rate of decline of wildlife has been particularly rapid in the last 100 years. So we have to make a check on the loss of biodiversity.Today we will study some of the causes of the loss/ extinction of biodiversity.There are a number of causes which are known to cause extinction of biodiversity.We will discuss these causes one by one:

 


1. DESTRUCTION OF HABITATS AND FRAGMENTATION:

This is the most serious threat to wildlife. Destruction of habitat leads to decrease in

hiding places and increased chances of predation. It is due to:

Pollution due to automobiles.

 

Deforestation

 

Soil erosion

 

Overgrazing

 

Urbanisation

 

Formation of dams, roads, railway lines etc .

 

Fragmentation is reduction of habitat in smaller and scattered areas. It results in

formation of smaller populations which are not able to sustain. Barriers are created

which limit the potential of species for proper dispersal and colonization.

 

2. INDISCRIMINATE HUNTING:Hunting of various animals for food, musk, tusk, horn, fur and for recreation purposes leads to loss of biodiversity. Excessive hunting is the main cause of extinction of Dodo and Cheetah.

 

3. OVER EXPLOITATION OF NATURAL RESOURCES:

Overfishing and mechanical catching of animal species is also a serious threat to

the wildlife.

 

4. DISTURBANCE IN MIGRATORY OUTES:

Construction of dams leads to disturbance in the migratory routes of some fishes so

these are not able to reach their spawning grounds and are facing extinction.

 

5. INTRODUCTION OF EXOTIC SPECIES:Due to introduction of exotic species native species are becoming extinct for example Parthenium (carrot grass) has replaced herbs and shrubs in open spaces.

 


6. HIGHWAYS:Large number of species of animals and plants become extinct during formation of highways. Moreover wild animals get confused and are run over by vehicles on the highways so decreasing their number.

 

7. LACK OF EDUCATION:Majority of people in world are not aware of the importance of the wildlife and ill effects of its destruction. So people must be properly educated to save the wildlife.

8. INTERNATIONAL TRADE IN INCREASING SCARCE ANIMAL PRODUCTS:Increase in the international trade of scarce animal products like perfume,cosmetics, medicines, museum, specimens, etc, is also the main cause of destruction of many species.

 

9. OFFICIAL LAXITY:Official laxity in the implementation of wildlife (protection) act.Most of the destruction of wildlife is avoidable.

 

10. ENVIRONMENTAL POLLUTION:Large scale use of synthetic compounds, release of radioactive chemicals, oil spills are polluting the rivers and oceans and reducing the species number. Lead poisoning is also causing death of many wildlife species.



So people all over the world must be educated about the benefits of the wildlife.

Seminars should be conducted in each and every street of the world and ill effects

of the loss of biodiversity should be discussed there.

 

LET US KNOW WHAT WE HAVE LEARNT!

PART: A - VERY SHORT ANSWER TYPE QUESTIONS:

A) MULTIPLE CHOICE QUESTIONS:

 

1. The biological wealth of our planet is declining rapidly due to?

a) animal activities

b) human activities

c) plant activities

d) ecological activities

 

2. Who gives the red list?

a) NSS

b) l1UCN

c) WHO

d) NCC

 

3. Which one of the following is said to be the most important cause for the

extinction of animals and plants?

a) Loss of habitat and fragmentation

b) Over exploitation of species

c) Invasion of alien species

d) Co extinctions

 

4. Which animals are badly affected when a large habitat is broken up into small fragments due to various human activities?

a) Extinct species

b) Migratory species

c) Non migratory species

d) Humans

 

5. The cause of loss of biodiversity is:

a) Indiscriminate hunting

b) Lack of education

c) Over exploitation of natural resources

d) All of the above

 

B) TRUE / FALSE:

1. Construction of highways and dams leads to increase in number of species.

2. Parthenium is friendly for native herbs and shrubs.

 

C) FILL IN THE BLANKS:

1. Due to disturbance in-—---- fishes are not able to reach their spawning grounds.

___ in increasing scarce animal products is the cause of destruction of many

species.

3. Soil erosion and overgrazing is the major cause of destruction of —--—-.

 

(A) MCQ'S:

1. (b) Human activities (various human activities like deforestation poaching ,

pollution and hunting is responsible for decreasing our biological wealth)

 

2. (b) IUCN (international union for conservation of nature and natural resources)

 

3. (a) Loss of habitats and fragmentation.

4. (b) migratory species (when habitat is broken into fragments migratory species

like fishes can't reach to their spawning areas)

 

5. (d) all of the above

 

(B) TRUE/ FALSE:

1. False. (during construction of highways and dams number of species decreases)

2. False (Parthenium is exotic species that has replaced native species of herbs

and shrubs of open spaces.

 

(C) FILL IN THE BLANKS:

1. Migratory routes

2. International trade

3. Habitats.

 

PART: B - SHORT ANSWER TYPE QUESTIONS:

Q1. Q1. How disturbance in migratory routes results in decrease of species

number?

Q2. What do you mean by fragmentation of habitats?

 

PART: C - LONG ANSWER TYPE QUESTION:

Q1. Explain causes of loss of biodiversity.

 

A177

 

INTRODUCTION

 

Biological diversity is currently decreasing at an alarming rate. In the long

geological history of earth, numerous species disappeared and new ones have

evolved.It is an irreversible loss because once a species become extinct it can never

reappear this is called extinction of species.

 

EXTINCTION OF SPECIES

Extinction of any species is an irreversible loss of part of the biological richness of

earth. Extinction happens when environmental factors or evolutionary problems causes a species to die out. Humans also cause other species to become extinct by hunting, overharvesting, introducing invasive species to the wild, polluting and changing wetlands forests to croplands and urban areas.

 

EXTINCTION OF SPECIES

Extinction of Species is of three types:

Natural extinction

 

Mass extinction

 

Anthropogenic extinction

 

1. Natural extinction:- Disappearance of old species due to changed environmental conditions is called natural extinction, in place of older species new species appear which are more adapted to changed environmental conditions.

 

2. Mass extinction:- Disappearance of large number of species due to catastrophes is called mass extinction, it has taken place many times of earth's surface 225 million years ago. A mass extinction occurred when 90% shallow water marine invertebrates disappeared.

 

3. Anthropogenic extinction:- There is too much pressure on earth’s surface due to rapid increase in human population. Large number of species become extinct due to human activities. The man-made mass extinction of

species is called as anthropogenic extinction. It severely damages biodiversity.

 


THE CHARACTERISTICS OF SPECIES WHICH ARE SUSCEPTIBLE TO EXTINCTION ARE GIVEN BELOW:

 

Large size of the body of the organism, for e.g. Bengal tiger, Lion and Elephant.

 

Low reproductive rate for e.g. Giant panda, Blue whale.

 

Localized and narrow range of distribution, for e.g. Woodland Caribou.

 

Feeding at high trophic levels in the food chain, for e.g. Bengal tiger & Bald Eagle.

 


Fixed habitat and migratory roots, for e.g. Blue Whale & Whooping Crane.

 

It was formerly known as international union for conservation of nature and natural resources or IUCN the international union for conservation of nature and natural resources has headquarters at Morges, in Switzerland IUCN’s Red Data Book is name given to the book dealing with threatened species of plants and animals of any region.

IUCN has recognized eight red list categories of species:-

Extinct

 

Extinct in wild

 

Critically Endangered

 

Endangered

 

Vulnerable

 

Lower risk

 

Data deficient

 

Not Evaluated

 


Extinct: Species which is no longer known to exist is called extinct. There is no doubt that the last individual of the species has died.

 

Extinct in the wild: Species that are no longer known to exist in the wild

but survive in cultivation are called extinct in wild.

 

Critically Endangered: A Taxon or species is critically endangered when it is facing high risk of extinction in the wild in the immediate future.

 

Endangered: A taxon or species is endangered when it is not critically endangered, but is facing high risk of extinction in the wild in nearfuture.There are few individuals in the species due to environmental or human

factors.

 

Vulnerable: These are the species whose population number is decreasing and likely to become more severely damaged with time in near future. They may represent the category of endangered species, if unfavorable conditions in the environment continue to operate.

 

Lower Risk: A taxon is in lower risk when it has been evaluated and does not fall in the category of critically endangered or vulnerable.

 

Data Deficient: A taxon is called data deficient when due to inadequate

information it is difficult to make assessment of its risk of extinction.

 

Not Evaluated: A species which has not been assessed against the above criteria is called not evaluated.



According to IUCN Red Data Book, Cheetah, Indian Rhinoceros, Pink headed duck and Forest Owlet have become extinct in India.

 


LET’S KNOW WHAT WE HAVE LEARNT!

(A) Multiple Choice Questions:

 

Q1: Which of the following is the pair of endangered species?

a) Garden Lizard

b) Rhesus monkey and Sal tree

c) Indian peacock and carrot grass

d) Hornbill and Indian Aconite

 

Q2: An extinct species can be genetically preserved in:

a) National park

b) Gene bank

c) Herbarium

d) None of these

 

Q3: Red data book includes list of:

a) Useful animals

b) Useful plants

c) Endangered species

d) Both a) and b)

 

Q4: According to IUCN red list what is the status of red panda?

a) Critically endangered species

b) Vulnerable species

c) Extinct species

d) Endangered Species

 

Q5: IUCN stands for:

a) Indian Union for Conservation of Nature

b) International Union for Conservation of Nature and Natural Resources

c) Indian Union for Chemical Nomenclature

d) International Union for Conservation for Nutrients

 

(B) True/False:

Q1: Keeping animals in zoological parks is not a cause for loss of

biodiversity.

Q2: Russia has the world’s highest diversity.

 

(C) Fill Ups:

Q1: The majority species facing extinction today are endangered because oft

Q2: The species may become endangered if proper steps are not taken are called_

Q3: IUCN stands for. .



 

PART:B SHORT ANSWER TYPE QUESTIONS:

Q1: Which institution maintain red data book?

Q2: Name three categories of threatened species.

Q3: Write two major uses of red data book.

Q4: What is the major cause of species loss in a geographical region?

 

PART:C LONG ANSWER TYPE QUESTIONS:

Q1: Write short note on the following:

a) Mass extinction b) Natural extinction —c) Critically endangered

Q2: What are three major threat categories of species? Describe with examples.

 

A178

 

INTRODUCTION

Why should we conserve biodiversity? What is the need of Biodiversity?

There are many reasons and all are important reasons that biodiversity needs to be conserved.

 

We can group the reasons to conserve BIODIVERSITY into three categories:

1) Narrowly utilitarian

2) Broadly utilitarian

3) Ethical utilitarian

 

1) NARROWLY UTILITARIAN:Humans derive countless economic benefits from nature. Food, firewood, fiber,construction material, industrial products, lubricants, dyes, resins, perfumes & products of medicinal importance.

 

2) BROADLY UTILITARIAN:Biodiversity plays major role in many ecosystem services.

“AMAZON FOREST is estimated to produce 20%of the total oxygen by the process of photosynthesis in earth’s atmosphere.

POLLINATION is another service, ecosystems provide through pollinators like bees, bumblebees, birds, & bats.

 

“AESTHETIC PLEASURES of walking through thick forests, watching spring flowers in full bloom &walking up to a bulbul’s song-intangible benefit we derive from nature is priceless

 

3) ETHICAL UTILITARIAN:Ethical argument for conserving biodiversity relates to what we owe to all plants,animals, and microbes species with which we share this planet. We need to realize that.

 

LET US KNOW WHAT WE HAVE LEARNT!

PART-A VERY SHORT ANSWER TYPE QUESTIONS:

A) MULTIPLE CHOICE QUESTIONS:

 

Q1 The ..................... arguments for conserving biodiversity are obvious.

a) narrowly utilitarian

b) broadly utilitarian

c) ethical

d) co extinctions.

 

Q2 How many species of plants contribute to the traditional medicines used by native people around the world?

a) 24000

b) 22000

c) 25000

d) 21000

 

Q3 Which argument says that biodiversity plays a major role in many ecosystem

services that nature provides?

a) narrowly utilitarian

b) Ethical

c) Broadly utilitarian

d) Habitat loss

 

Q4 Plants cannot give us fruit or seeds without:

a) Pollination

b) Endemism

c) Co extinction

d) Sacred grove

 

Q5. Which argument is used for conserving biodiversity relate to what we owe to millions of plants , animal or microbe species?

a) narrowly utilitarian

b) Broadly utilitarian

c) Ethical

d) Co extinction

 

Q6: How many percent of total oxygen in earth’s atmosphere is produced by Amazon forest?

a) 20 percent

b) 30 percent

c) 40 percent

d) 50 percent

 

 

 

Q7: Which of the following does not contribute for means of conservarion of biodiversity?

a) intrinsic value

b) Economic value

c) Ethical value

d) None of these

 

Q8: Which of the following is not a pollinator?

a) bumblebees

b) Birds

c) Bats

d) Spirogyra

 

Q9: What is bioprospecting?

a) most important cause driving animals and plants to extinction

b) Exploring molecular genetics and species level diversity for product of economic importance

c) Argument for conserving biodiversity

d) Protect the whole ecosytem

 

Q10:The narrowly utilitarian products include:

a) cereals, pulses, fruits

b) Construction material

c) Tannins, lubricants, dyes

d) All the above

 

B) TRUE/FALSE:-

1. Philosophically or spiritually we need to realize every species has an intrinsic

value.

2. Amazon forest is estimated to produce 80 percent of total oxygen in earth's

atmosphere.

3. Biodiversity plays a major role in many ecosystem services that nature provides.

4. Bats do not act as pollinators.

5. Biodiversity does not have spiritual importance.

 

ANSWER KEY: PART -A

A. MCQs:

 

1. a) Narrowly utilitarian (because we get economic benefits)

2. c) 25000 (25% of drugs are derived from plants worldwide)

3. c) Broadly utilitarian (pollination, oxygen release by forests)

4. a) Pollination (fertilization is possible only after pollination)

5. c) Ethical (because each and every species has its own value)

6. a) 20 percent

7. d) None of these

8. d) Spirogyra

9. b) Exploring molecular genetics and species level diversity for product of

economic importance.

10. d) All the above

 

B. TRUE/FALSE:

1.TRUE(each species is a part of various food chains)

2.FALSE(actual percentage is 20%)

3. TRUE(biodiversity is important for many ecosystem services)

4.FALSE(bats undergo chiropterophily type pollination in plants

5.FALSE(biodiversity has a lot of spiritual value)

 

PART-B SHORT ANSWER TYPE QUESTIONS:

Q.1) Why should we conserve biodiversity?

Q.2) Define ethical argument for conserving biodiversity?

Q.3) Explain economic benefits that we get from nature?

 

PART- C LONG ANSWER TYPE QUESTIONS:

Q.1) Differentiate narrowly utilitarian and broadly utilitarian arguments for

conserving biodiversity?

 

A179

 

INTRODUCTION

IN SITU CONSERVATION :It is conservation and protection of whole ecosystem and its biodiversity of all levels IN THEIR ORIGINAL PLACE in order to protect the threatened species.It is not economically possible to conserve or biological wealth and all existing ecosystems. The number of

Species which are required to be saved from extinction is far greater than the

conservation resources.

 

Two alternate methods are being used to save biodiversity, HOT SPOTS and PROTECTED AREAS.

 

1.HOT SPOTS:Conservationist identified for maximum protection certain ‘biodiversity hotspots’.These are the 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). These are also regions of accelerated habitat loss. Initially 25 biodiversity hot spots were identified. Later on nine more have been added to the list. So now there are 34. Three of these hotspots Western

Ghats and Shri Lanka, Indo Burma and Himalya are in India. These cover our country’s exceptionally high biodiversity region. Although all the biodiversity hotspots put together cover less than 2% of the earth's land area, They have extremely high number of species. So strict protection of these hotspots could reduce the present mass extinction by almost 30%.

 

2.PROTECTED AREAS:These are ecological areas where biological diversity along with natural and cultural resources is protected, maintained and managed through legal or other

effective measures. Protected area include national parks, sanctuaries and biosphere reserve.

 

a)National Parks:These are areas maintained by government and reversed for betterment of wild life. Cultivation, grazing, forestry and habit manipulation are not allowed. At

present India has 90 national parks occupying nearly 1.1% of geographical area. The first national park of India was Jim Corbett National Park.

 

b)Sanctuaries:These are tract of land where wild animal can take refuge without being hunted other activities like collection of forest products harvesting of timber private

ownership of land extra allowed India has 448 wildlife sanctuaries occupying 3.6% of geographical area.

 

c)Biosphere Reserve:These are multipurpose protected area which are meant for preserving a genetic diversity in ecosystem of various natural biomes and unique biological

communities by protecting wild population, traditional lifestyle of tribals and domesticated plant, animal genetic resources. Creation of biosphere reserve was initiated in 1975 under MAB (man and biosphere)

programme of UNESCO. Till may 2002,408 biosphere reserves had been established in 94 countries. Indian now has 14 biosphere reserves. Each biosphere reserve has following Zones:

 

1.Core or Natural zone:No human activity is allowed the area is un .distributed and legally protected ecosystem.

 

2.Buffer Zone:It surrounds the core area limited human activity is allowed.

 

3.Transition Zone (Manipulation Zone):

It is the outer most part of biosphere reserve where an active cooperation is

present between reserve management and local people. Activities like settlements,

cropping, recreation, foresty are allowed but without disturbing the ecology.

 

ZONES OF BIOSPHERE:-



IMPORTANCE OF BIOSPHERE RESERVES:

1.Restoration: Biosphere reserve help in Restoration of degraded ecosystem and habitats.

 

2.Conservation: They are means of conserving genetic resources,species, ecosystem and landscapes without uprooting the local People.

 

3.Development: They ensure culturally, socially and ecologically sustainable economic development.

 

4.Education and Research: Each biosphere reserve support education and research in various ecological aspect of the ecosystem.

Sacred forests and Lakes:india has also a history of religious and cultural tradition that lay stress on protection of nature. In many cultures, tracts of forest where set aside. All the trees and wild life within were given total protection. This sacred groves are found in khasi and jaintia Hills in Meghalaya,Aravalli Hills of Rajasthan, Western Ghat region of Karnataka and Maharashtra and the Sarguja , Chanda andBastar areas of Madhya Pradesh. In Meghalaya,the sacred groves are the last refuges for the large number of rare and

threatened species.Bishnois of Rajasthan protected Prosopis cineraria and black buck religiously.Some water bodies are also held sacred in certain places. Example:

Khecheopalri in Sikkim. Their aquatic flora and fauna are naturally preserved.

  

“LET’S KNOW WHAT WE HAVE LEARNT!”

PART: A VERY SHORT ANSWER TYPE QUESTIONS:

A. MULTIPLE CHOICE QUESTIONS :

 

1) Which of the following is not the approach for in-situ conservation?

a) Biosphere reserve

b) Sanctuary

c) Wild life safari park

d) Sacred groove

 

2) Which one of the following pairs of geographical areas show maximum

biodiversity in our country?

(a) Sunderbans and Rann of Kutch

(b) Eastern Ghats and West Bengal

(c) Eastern Himalaya and Western Ghats

(d) Kerala and Punjab

 

3) Which of the following is considered a hot-spot of biodiversity in India?

a) Indo-Gangetic plain

b) Eastern Ghats

c) Aravalli Hills

d) Western Ghats

 

 

4) Which of the following is not observed in biodiversity hotspots?

a) Species richness

b) Endemism

c) Accelerated inter-specific competition

d) Lesser inter-specific competition

 

5) Hotspots of biodiversity means:

a) Areas of the earth that contain many endemic species.

b) Species serves as proxy for entire communities in particular area.

c) Species in particular niche/area.

d) Species diversity at particular area.

 

B. FILL IN THE BLANKS:

1) The area where wild population, traditional life style and genetic resources are protected is called .

2) Animals and plants are best protected in .

3) Sacred groves of Sarguja, Chanda and Baster are present in .

 

C. TRUE/FALSE:

1) Core zone buffer zone and manipulation zone are found in Biosphere reserve

(true/false).

2) Total number of biodiversity hot spots in the world is 25 (true/false)

 

 

 

ANSWER KEY: PART —-A

A. MULTIPLE CHOICE QUESTIONS:

 

1. (c) Wild life safari park.

HINT: In situ conservation is the conservation of genetic resources within natural or human-made ecosystems in which they occur. E.g. protected areas such asnational parks, sanctuaries, biosphere reserves, cultural landscapes, natural monuments

 

2. (c) Eastern Himalya and Western Ghats

HINT: Eastern Himalayan and Western Ghats are the hotspot area which shows maximum biodiversity in our country.

 

3. (d) Western Ghats.

HINT: Hot spots are the areas or regions of high endemism andf very high levels of

species richness. These are the richest and the most threatened reservoirs of plant

and animal life on earth. There are 34 hot spots in the world, of which three are in

India; namely Western Ghats and Sri Lanka, Indo-Burma and Himalaya.

 

4. (d) Lesser inter-specific competition.

HINT: Inter-specific competition is less in biodiversity hotspots.

 

5. (c) Indian Union for Chemical Nomenclature.HINT: Hot spots are the areas or regions of high endemism and very high levels of species richness. These are the richest and the most threatened reservoirs of plant

and animal life on earth.

 

B. FILL IN THE BLANKS:

1. Biosphere reserve

HINT: Biosphere reserve is an area created to protect the biological and cultural

diversity of a region. It is a place of collaboration, education and experimentation,where scientists etc. can share research data to better understand man's impact on

nature, and where local communities, environmental groups, and economic interestscan work collaboratively on conservation and development issue.

 

2. National parks

HINT: National Park is a protected area, which is strictly reserved for the welfare of the wildlife and where activities like forestry, grazing and cultivation are not permitted.Their boundaries are well marked and circumscribed. In national parks, theemphasis is on the preservation of a single plant or animal species.

 

3. Madhya Pardesh HINT: Sacred groves of Sarguja, Chanda and Baster are present in Madhya Pardesh.

 

C. TRUE/FALSE:

1. TRUE

HINT: Each biosphere reserve has folloeing zones: Core or national zone, Buffer

zone and Transition zone(manipulation zone).

2. FALSE

HINT: Total number of biodiversity hot spots in the world is 34.

 

PART: B SHORT ANSWER TYPE QUESTIONS:

1. What is Biosphere reserve?

2. Why is biosphere called a life supporting zone of earth?

3. Difference between national park and sanctuaries.

 

PART: C LONG ANSWER TYPE QUESTION:

1. What are sacred groves? What is their role in conservation?

 

A180

 

INTRODUCTION

Biodiversity -The wide variety of plants and animals along with microorganisms living in a particular region is called biodiversity.

 


Importance of biodiversity -“ Stability: Ecologists believed that communities with more species, generally,tend to be more stable than those with less species.

 

Productivity: Increased diversity contributes to higher productivity.

 

Health of Ecosystem: Rich biodiversity is essential for Ecosystem health and

survival of human race.

 

WHY SHOULD WE CONSERVE BIODIVERSITY?

Reason of conservation is grouped into three categories:-

 

Narrowly utilitarian: Countless direct economic benefits from nature such as

fruits, vegetables, cereals, pulses, firewood, fibre, industrial products and

medicinal products.

 

Broadly utilitarian: Biodiversity plays a major role in many ecosystem services e.g.:Amazon Forest is estimated to produce 20% of total oxygen in the earth's atmosphere through photosynthesis.

 

Ethical: We have a moral duty to care for their well - being and pass on our biological legacy in good order to future generations.

 


HOW DO WE CONSERVE BIODIVERSITY?

Conservation of biodiversity: It is the management of the biosphere in such a way

that it may yield the sustainable benefit to the present generation while maintaining

its potential to meet the needs of future generations.

1. To maintain essential life supporting systems such as air, water and soil.

2. To preserve the diversity of species or the range of genetic material.

Major Biodiversity conservation methods are:

A) In - situ conservation - It refers to on - site conservation in which threatened

species are protected in their natural habitat

 


B) Ex -situ conservation - Threatened animals and plants are taken out from their

natural habitat and are placed in special environments where they can be protected

and given special care.



EX - SITU CONSERVATION

 

Now we will study ex - situ conservation in detail:-

Few methods of ex - sifu conservation are:-

 

1. Seed gene bank or germplasm bank-

The term Seed bank refers to cryogenic laboratory facilities in which the seeds of

some species are kept viable for long period. This is the easiest way to store

the germplasm of plants at low temperature.

 

2. Field gene bank-Genetic variabilitycan also bepreserved by field gene bank under normal growing conditions .The gene banks are used to store living sperms, eggs or embryos.

3. Cryopreservation-Gametes of threatened species can be preserved in viable and fertile conditions for long periods at very low temperatures of -196 degree Celsius in liquid nitrogen .This technique is highly successful in crops like potato .

 

4. Botanical Parks In  botanicalgardensparticular trees and shrubs are grown.|n these gardens more than 80000 speciesare found.Many botanical gardens have the facilities of Seed bank, tissue culture and latest techniques of ex - situ conservation.

 

5. Zoological Parks—There are about 800 zoos in the world. These zoos have 3000 species of vertebrates. Some zoos have undertaken captive breeding programmes.Captive breeding is the process of maintaining plants and animals in controlled environment.

 


LET US KNOW WHAT WE HAVE LEARNT!

PART: A- VERY SHORT ANSWER TYPE QUESTIONS:

A) MULTIPLE CHOICE QUESTIONS;

 

1. What is the protection and conservation of species outside their natural habitat called?

a) No conservation

b) Ex-situ conservation

c) Biosphere reserves

d) In-situ conservation

 

2. In which approach do we protect and conserve the whole ecosystem to protect the endangered species?

a) Ex-situ conservation

b) Off-site conservation

c) No conservation

d) In-situ conservation

 

3. In Cryopreservation gametes of threatened species are preserved for long time at temperature:

a) -190 °C

b) -196 °C

c) -195 °C

d) -193 °C

 

4. By which of the following techniques the gametes of threatened species are preserved in viable and fertile conditions for long periods?

a) Botanical gardens

b) Cryopreservation techniques

c) Zoological parks,

d) Wildlife safari parks

 

5. Which of the following is an odd one?

a) Botanical gardens

b) Zoological parks

c) Wildlife safari parks

d) National parks

 

B) TRUE / FALSE:

1) Seed gene bank is the way to store the germplasm of plants at high temperatures.

2) Cryopreservation is a type of conservation at very low temperature of -196 degree Celsius in liquid nitrogen.

 

C) FILL IN THE BLANKS

1) In world there are about ------—- zoos

2) Amazon forest is estimated to produce -----—---—% of total oxygen in the earth's atmosphere.

3) The variety of plants , animals and microorganisms living in a particular region is

called ---—---—--— .

 

ANSWER KEY: -PART-A

(A) MCQs:

 

1. (b) Ex - Situ conservation (outside natural habitats like zoo, aquarium etc. )

2. (d) In- Situ conservation (like national parks, sanctuaries, biosphere reserve etc)

3. (b) -196 degree Celsius (temperature of liquid nitrogen)

4. (b) Cryopreservation techniques

5. (d) National Parks (It is In-Situ conservation technique)

 

(B) TRUE /FALSE:

1) False (in this we store the germplasm of plants at low temperature)

2) True

 

(C) FILL IN THE BLANKS:

1) 800

2) 20%

3) Biodiversity

 

 

 

PART: B- SHORT ANSWER TYPE QUESTIONS:

1). What is biodiversity conservation? Write different ways to conserve Biodiversity.

2). What is cryopreservation?

3). Write difference between ex -situ conservation and in-situ conservation.

 

PART: C - LONG ANSWER TYPE QUESTIONS:

1) What is Ex - Situ conservation? Explain different ways of Ex-Situ conservation?

 

A181

 

RECAPITULATION

Dear students in this Chapter “BIODIVERSITY AND CONSERVATION”, you have read all the topics of this chapter in detail.

 

As this chapter deals with biological diversity, which is the occurrence of different types of ecosystems, different species of an organisms with

the whole range of their variant and genes adapted to different climates,

environments along with their interactions.

 

NCERT EXERCISE QUESTIONS:

Q.1. Name the three important components of biodiversity?

Ans. 1. Genetic diversity

2. Species diversity

3. Ecological diversity

 

Q.2. How do ecologists estimate the total number of species present in the world?

Ans. Ecologists can estimate the total number of species on earth through a statistical comparison between species richness of a well-studied group of insects of tropical and temperate regions. Later these ratios are extrapolated with groups of other plants and animals to estimate the net species richness on earth.Robert May has estimated the number of species to be 7 million.

 

Q.3. Give three hypotheses for explaining why tropics show the greatest levels of species richness?

Ans.

1. Speciation is generally a function of time. Tropics have remained without any

disturbance from glaciations for millions of year and thus time for species richness.

 

2. Tropical environments are less seasonal and are relatively more constant and

predictable.

 

3. There is more solar energy available in the tropics which contribute to higher

productivity.

 

Q.4. What is the significance of the slope of regression in a species-area relationship?

Ans. The slope of regression makes it easier to measure species richness along an area. Alexander Von Humboldt observed that within a region species richness increases with increasing explored area but only up to a limit (0.1 to 0.2). On a logarithmic scale, the relationship is a straight line. When the analysis is taken on large areas like entire continents, slope of line will be much steeper (0.6 to 1.2).

 

Q.5. What are the major causes of species losses in a geographical region?

Ans.The major cause of species losses are:

1. Habitat loss and fragmentation: This is the most important cause driving plants

and animals to extinction. Uncontrolled and un-sustainable human activities such as

deforestation, burning, mining etc. lead to the destruction of habitats of many

species.

 

2. Over exploitation: Human always depend upon nature for food and shelter but

when need turns to greed, it leads to over exploitation of natural resources.

 

3. Alien species invasions: When alien species are introduced unintentionally or

deliberately for whatever purpose, some of them turn invasive and cause decline or

extinction of other native species. For example: carrot grass (Parthenium) , water

hyacinth ( Eichhornia).

 

4. Co-extinctions: When a species becomes extinct, the plant and animal species

associated with that in an obligatory way also become extinct. For example, in case

of a coevolved plant pollinator mutualism where extinction of one invariably leads to

the extinction of the other.

 

Q.6. How is biodiversity important for ecosystem functioning?

Ans.1. Humans derive countless direct benefit from nature food cereals, fruits,firewood, fiber, construction material and many medicinal products.

 

2. The rich biodiversity is important for stability, productivity and for health of

ecosystem. D. Tilman confirmed that higher the biodiversity, higher is the productivity.

 

3. Rich biodiversity provides resilience against natural/ manmade disturbances.

 

4. The species richness is essential for ecosystem health and survival of human

race.

 

5. If an ecosystem is rich in species, each tropic level will have other food

alternatives which would increase the life expectancy.

 

6. As different trophic levels are connected through food chains, illness /missing

of one organism at any tropic level would disrupt the whole food chain.

 

Q.7. What are sacred groves? What Is the role in conservation?

Ans. Sacred groves are the traditionally protected patches of forests around

place of worship where the local tribal do not allow cutting the trees. These are

found in Western Ghats of Karnataka, Rajasthan, Maharashtra and Meghalaya.

These groves help in Safeguard the threatened, rare and endemic species of animals and plants.

 

Q.8. Among the Ecosystem services are control of floods and soil erosion. How is this achieved by the both biotic components of the ecosystem?

Ans. Ecosystem has two types of components: A biotic components are air,water; temperature and Biotic components are constituted by the animals, plants and human beings. The role of plants is crucial in controlling soil erosion and floods as plant roots secure and bind the soil particles together, thus inhibiting the

top layer of the soil to get eroded by running water or wind. Further, plant roots

cause porosity of the soil to enable the groundwater infiltration and averting the

floods.They also increase biodiversity and fertility of soil. That is why plants are helpful to prevent soil erosion and natural calamities such as droughts and floods.

 

Q.9. The species diversity of plants (22%) is much less than of animals (72%).What could be the explanation to how animals achieved greater diversity?

Ans. Animals have achieved greater diversification than plants due to following

reasons:

1. They have a central nervous system to receive stimuli and respond to it

which is better to survival in adverse situations.

 

2 They are mobile to avoid competition whereas; plants are fixed and less chance to avoid competition.

 

3. They are subjected to more stable environment and to less seasonal environment.

 

4. Plants are fixed and they require more evolutionary adaptations in order to

obtain their requirements of water, minerals, sunlight and avoiding herbivores.Thus, there is a higher diversity among animals than plants.

 

10. Can you think of a situation where we deliberately want to make a species extinct? How would you justify it?

Ans. Yes, some harmful pathogens i.e. disease-causing organisms with little or

no role in the ecosystem can be made to get extinct. Their extinction will not lead

to any effect on the ecological balance. These pathogens may include smallpox

virus is about to get eradicated. There are efforts to make this world free from

diseases such as TB, Malaria, and Aids etc. Since the microorganisms causing

these diseases have no role to play in the environment, they can be made to get

eradicated.

 

A182

 

INTRODUCTION

 

Dear students in this chapter

“BIODIVERSITY AND CONSERVATION”, we have taken all the topics of this chapter in detail. As this chapter deals with biological

diversity which includes more than 20000 species of ants 300,000 species of beetles 28,000 species of fishes and nearly about 20,000 species of orchids.

 

Now, we shall revise the whole chapter topic wise:in our Diospnere, Immense aiversily (neterogenelty )exists not only at the species level but at all levels of biological organization ranging from the macromolecules within cells to biomass. Biodiversity term

was popularized by the Sociobiologist, Edward Wilson.There are three main components of biodiversity:

 

1. GENETIC BIODIVERSITY: A single species might show high diversity at the genetic level over its distributional range. the genetic variation shown by the medicinal plant Rauwolfia vomitoria growing in different Himalayan ranges might be in term of its potency and concentration of

active chemical (reserpine) . Similarly, there are more than 50,000 genetically different strains of rice and 1000 varieties of mango.

 

2 SPECIES DIVERSITY: The diversity at the species level. The number of species per unit area is called as Species richness. For

example: the Western Ghats have a greater amphibian species diversity than the Eastern Ghats.

 

3. ECOLOGICAL DIVERSITY: it represents the diversity in the availability of various types of ecosystem in a given area. In comparison with Norway, India has a greater ecosystem diversity with its desert,

rainforests, mangroves, coral reefs, wetlands , estuaries and alpine meadows.

 

2. NUMBER OF SPECIES IN INDIA AND ON EARTH :

According to IUCN (International union for Conservation of Nature), the total number of plants and animals species is slightly more than 1.5 million. Robert May places the global species diversity at about 7

million. More than 70% of all the species recorded are animals while plan (algae, fungi, bryophytes, gymnosperm and  angiosperm). Among animals insects are the richest species.

 


PATTERN OF BIODIVERSITY:

LATITUDINAL GRADIENTS:The species diversity decreases as we move away from the equator towards the poles. Tropics, have (latitudinal range of 23.5 N to 23.5 S) more species

han the temperate or polar areas.Colombia located near equator has nearly 1400 species of birds while New York at 41 N only 56 species. The Amazon rain forest in South America has the greatest biodiversity on earth with home for more than 40,000 species of plants, 3000 species of fishes, 1300 birds, 427 of mammals and 378 reptiles

Tropic > Temperate > Polar 



The great German naturalist and geographer Alexander Von Humboldt,observed that within a region species richness increased with increasing explored area but only up to a limit (0.1 to 0.2). On a logarithmic scale, the relationship is a straight line. When the analysis is taken on large areas like entire continents, slope of line will be much steeper (0.6 to 1.2).

 


IMPORTANCE OF SPECIES DIVERSITY TO THE ECOSYSTEM:A stable community should not show too many variations in productivity from year to year, it must be either resistant or

resilient to occasional disturbances and it must be resistant to invasions by

alien species. Paul Ehrlich gave Rivet Popper hypothesis which impacts of extinction of the species on the ecosystem through an air plane analogy.

 

LOSS OF BIODIVERSITY:IUCN Red list is the world’s most comprehensive inventory

of the global conservation status of biological species.Example of recent extinctions:

Dodo Mauritius

Quagga Africa

Thylacine Australia

Steller's seacow Russia

 

EXTINCT = Species that have ceased to exist

 

ENDANGERED = facing high risk of extinction in near future

 

CRITICALLY ENDANGERED = can become extinct at any moment in immediate Future

 

VULNERABLE = may become extinct in medium term future.

 

CAUSES OF BIODIVERSITY LOSS:

1. Habitat loss and fragmentation: Uncontrolled and un sustainable human activities such as deforestation, burning, mining etc. lead to the destruction of habitats of many species.

 

2 Over exploitation: Human always depend upon nature for food and shelter but when need turns to greed, it leads to over exploitation of natural resources.

 

3. Alien species invasions: When alien species are introduced unintentionally or deliberately for wnatever purpose, some of them turn invasive and cause decline or extinction of other native species. For

example: carrot grass (Parthenium), water hyacinth ( Eicchornia) .

 

4. Co-extinctions: When a species becomes extinct, the plant and animal species associated with id in an obligatory way also becomes extinct. For example, in case of a coevolved plant pollinator mutualism

where extinction of one invariably leads to the extinction of the other.

 

HOW TO CONSERVE BIODIVERSITY?

 

IN SITU CONVERSATION:It is on site conservation. It includes Hotspot which are 34 in number.

 

BIOSPHERE: it is a region with significant reservoir of biodiversity that is under threat from human. India has 14 biospheres reserves.

 

For example: Nanda Devi, Uttarakhand, Gulf of Mannar, Tamil Nadu.

 

NATIONAL PARKS: These are maintained by the government and reserved for betterment of wildlife and in India there are 90 National

Park.

 

WILD SANCTUARIES: These are tracts of land with or without a lake where wild animals refuse without hunting and in India there are 448 wildlife sanctuaries.

 

SACRED GROVES: Sacred groves are the traditionally protected patches of forests around place of worship where the local tribal do not allow cutting the trees.

 

EX-SITU CONSERVATION’ In this approach,wild animals and plants are taken out of their natural habitat and placed in special places.

Zoological Park, Botanical Park, and wildlife Safari serve this purpose.Now ,Gametes of threatened species could be preserved in viable and fertile condition for long period using Crypto preservation ,eggs can be fertilized in vitro and plants could be propagated using tissue culture methods .

 

IMPORTANT DAYS:

03 March: World Wildlife Day

22 April: Earth day

05 June: world environment day

08 June: World ocean day

16 September: World Ozone day

04 October: World animal day

21 March: World Forest day

 

EARTH SUMMIT 1992:Held in, Rio de Janerio, for conservation of biodiversity and its benefits.

 

WORLD SUMMIT ON SUSTAINABLE DEVELOPMENT-2002:

Held in Johannesburg, South Africa by 190 countries, for reduction in, current

rate of biodiversity-loss, at global, regional and local levels.

Chapter 15 Biodversity and Conservation