biology-class-12-unit-15-chapter-03-ecology-biodiversity-and-conservation-lecture-3-3-fy-txkagkui

<h3 id="successhabitat-loss-and-fragmentationsuccess"><Success>Habitat loss and fragmentation</Success></h3>
<div style='float: left; width:100%;font-size:30px; text-align:left;'>
<ul>
<li>Most important cause for extinction of plants and animals</li>
<li>The area covered by tropical rain forests have drastically reduced from 14% of the earth’surface to less than 6%</li>
<li>The Amazon rain forest is being cut and cleared for cultivating soybeans or for conversion to grasslands for raising beef cattle</li>
<li>Human activities like pollution, agriculture, settlements etc. are degrading many habitats or breaking them into small fragments</li>
<li>Fragmentation, largely, affects migratory birds and those animals requiring large territories</li>
</ul>
</div>
<div style='float: right; width:0%;'>
<p><img alt="image" src="https://temp-public-img-folder.s3.ap-south-1.amazonaws.com/sathee.prutor.images/subject-images/iitpal/image/biology-class-12-unit-15-chapter-03-ecology-biodiversity-and-conservation-lecture-3_3-fy-txkagkui-08.jpg"></p>
</div>

<h3 id="successoverexploitationsuccess"><Success>Overexploitation</Success></h3>
<div style='float: left; width:100%;font-size:30px; text-align:left;'>






<ul>
<li>“Earth provides enough to satisfy every man’s need, but not every man’s greed”</li>
<li>Detrimental Human Activities</li>
<li>Increased human population means more demand on nature’s limited resources</li>
<li>Wasting of resources and polluting it</li>
</ul>
</div>
<div style='float: right; width:0%;'>


</div>

<h3 id="successoverexploitationsuccess-1"><Success>Overexploitation</Success></h3>
<div style='float: left; width:100%;font-size:30px; text-align:left;'>






<ul>
<li>Overharvesting of marine fishes</li>
<li>Poaching and hunting</li>
<li>Mining and Burning of fossil fuels</li>
<li>Science and technology further adding artificial non biodegradable materials into the environment</li>
</ul>
</div>
<div style='float: right; width:0%;'>


</div>

<h3 id="successalien-species-invasionsuccess"><Success>Alien Species Invasion</Success></h3>
<div style='float: left; width:100%;font-size:30px;text-align:left;'>
<ul>
<li>
<p>Introduction of alien species leads to decline or extinction of indigenous species</p>
</li>
<li>
<p>Examples of Alien Species Invasion -</p>
</li>
<li>
<p>Invasive weeds like Parthenium, Lantana and water hyacinth (Eicchomia) has posed   threat to our native species</p>
</li>
<li>
<p>The Nile perch introduced into Lake Victoria in E.Africa led to extinction of more than 200 species of Cichlid fishes</p>
</li>
<li>
<p>Illegal introduction of African catfish Clarias gariepinus for aquaculture is posing threat to indigenous catfishes</p>
 </div>
 <div style='float: right; width:0%;'>
 	
</li>
</ul>

<h3 id="successco-extinctionssuccess"><Success>Co-extinctions</Success></h3>
<div style='float: left; width:100%;font-size:30px; text-align:left;'>
<ul>
<li>
<p>Species interactions in some organisms are tight one-to-one relationship i.e. they have co-evolved</p>
</li>
<li>
<p>For example - A given Fig species can be pollinated only by its ‘partner’ wasp species. The female wasp uses the fruit for oviposition and nourishes its larvae by developing seeds within the fruit</p>
</li>
</ul>












</div>
<div style='float: right; width:50%;'>


</div>

<h3 id="successwhy-should-we-conserve-biodiversitysuccess"><Success>Why should we conserve Biodiversity?</Success></h3>
<div style='float: left; width:100%;font-size:30px; text-align:left;'>
<table>
<thead>
<tr>
<th>Narrowly Utilitarian</th>
<th>Broadly Utilitarian</th>
<th>Ethical</th>
</tr>
</thead>
<tbody>
<tr>
<td>Direct, tangible or economic Benefits</td>
<td>Indirect, non tangible ecosystem services</td>
<td>Putting an intrinsic value to all living organism as per morals and ethics</td>
</tr>
<tr>
<td>Food (cereals, pulses, fruits, vegetables, spices)</td>
<td></td>
<td></td>
</tr>
<tr>
<td>Firewood and Timber</td>
<td>Production of oxygen by trees in a forest</td>
<td>We, being a part of nature owe something to all fellow species</td>
</tr>
</tbody>
</table>
</div>
<div style='float: right; width:50%;'>

</div>

<h3 id="successin-situ-conservationsuccess"><Success>In situ conservation</Success></h3>
<div style='float: left; width:100%;font-size:30px; text-align:left;'>
<ul>
<li>When we conserve and protect the whole ecosystem, its biodiversity at all level is protected</li>
<li>This approach is In-situ or on the site conservation where species are facing the threat of extinction</li>
<li>Conserving all biological wealth seems unrealistic and uneconomical to many nations faced with the conflict of development</li>
<li>Number of species waiting to be conserved far exceeds the conservation resources available
<ul>
<li>Eminent conservationists have addresses this problem by identifying ‘Biodiversity Hot spots’</li>
</ul>
</li>
</ul>







</div>
<div style='float: right; width:25%;'>

<h3 id="successbiodiversity-hot-spotssuccess"><Success>Biodiversity hot spots</Success></h3>
<div style='float: left; width:100%;font-size:30px; text-align:left;'>






<p>A biodiversity hotspot is characterized by -</p>
<ol>
<li>
<p>High level of species richness</p>
</li>
<li>
<p>High degree of endemism</p>
</li>
<li>
<p>Enormous threat of destruction</p>
</li>
</ol>
<ul>
<li>
<p>Initially 25 biodiversity hotspots were identified but later 10 more have been added bringing it to a total of 35      hotspots currently.</p>
</li>
<li>
<p>Although these hotspots put together cover less than 2% of earth’s land area, strict protection of these can reduce    the ongoing mass extinction by 30%.</p>
</li>
</ul>
</div>
<div style='float: right; width:25%;'>

<h3 id="success4-biodiversity-hot-spots-have-been-identified-in-indiasuccess"><Success>4 biodiversity hot spots have been identified in India</Success></h3>
<div style='float: left; width:50%;font-size:30px; '>
<ul>
<li>
<p>Eastern Himalayas</p>
</li>
<li>
<p>Indo-Burma</p>
</li>
<li>
<p>Western Ghats</p>
</li>
<li>
<p>Sundaland in India-Malayan archipelego</p>
</li>
</ul>
</div>
<div style='float: right; width:50%;'>
<img src="https://imagedelivery.net/YfdZ0yYuJi8R0IouXWrMsA/0b63fc2b-051e-453a-33f7-f42076f79900/public" width="100%">



</div>

<h3 id="successin-situ-conservation-methodssuccess"><Success>In situ conservation methods</Success></h3>
<div style='float: left; width:60%;font-size:28px; '>
<ul>
<li>On the site conservation of ecosystem and species within</li>
<li>Involves conservation of Biodiversity within their natural ecosystem</li>
<li>Natural habitats are declared as Protected Areas</li>
<li>Protected Area Network (PAN) includes Biosphere reserves, National Parks, Wildlife sanctuaries and Sacred grooves</li>
<li>India has 18 Biosphere reserves, 102 National Parks and 515 wildlife sanctuaries</li>
</ul>
</div>
<div style='float: right; width:40%;'>
<img src="https://imagedelivery.net/YfdZ0yYuJi8R0IouXWrMsA/0b63fc2b-051e-453a-33f7-f42076f79900/public" width="100%">

	<!--![image](https://temp-public-img-folder.s3.ap-south-1.amazonaws.com/sathee.prutor.images/subject-images/iitpal/image/biology-class-12-unit-15-chapter-03-ecology-biodiversity-and-conservation-lecture-3_3-fy-txkagkui-138-2365.2.jpg)-->

<pre><code>### <Success>In situ conservation methods</Success>
</code></pre>
<div style='float: left; width:70%;font-size:30px; text-align:left;'>
<ul>
<li>
<p>Biosphere Reserve Established under UNESCO’s ‘Man and the
Biosphere Programme, biosphere reserves are a series of protected areas linked through a global network, intended to   demonstrate relationship between conservation and development.</p>
</li>
<li>
<p>National Parks → National Park is an area having adequate ecological, faunal, floral, natural or zoological            significance.</p>
</li>
<li>
<p>Wildlife Sanctuaries → Certain rights of people living inside the Sanctuary could be permitted, otherwise it’s same    as a National Park.</p>
</li>
</ul>
</div>
<div style='float: right; width:30%;'>
<img src="https://imagedelivery.net/YfdZ0yYuJi8R0IouXWrMsA/0b63fc2b-051e-453a-33f7-f42076f79900/public" width="100%">

<h3 id="successin-situ-conservation-methodssuccess-1"><Success>In situ conservation methods</Success></h3>
<div style='float: left; width:60%;font-size:30px; text-align:left;'>
<ul>
<li>Sacred Grooves These are certain tracts of forests which are venerated and given total protection by a community       because of religious or cultural connotation. Examples: Khasi and Jaintia hills in Meghalaya, Aravalli hills of        Rajasthan, Western ghat regions of Karnataka and Maharashtra, Sarguja, Bastar and Chanda regions of Madhya Pradesh.</li>
</ul>
</div>
<div style='float: right; width:40%;'>
<p><img src="https://imagedelivery.net/YfdZ0yYuJi8R0IouXWrMsA/0b63fc2b-051e-453a-33f7-f42076f79900/public" width="100%">

<h3 id="successconcern-for-biodiversity-conservation-at-national-levelsuccess"><Success>Concern for biodiversity conservation at national level</Success></h3>
<div style='float: left; width:100%;font-size:30px; '>
<ul>
<li>India is home to world’s largest wild tigers population</li>
<li>It has got unique assemblage of globally important endangered species like Asiatic lion, Asian Elephant, One-horned Rhinoceros, Gangetic River Dolphin, Snow Leopard, Kashmir Stag, Dugong, Gharial, Great Indian Bustard, Lion Tailed Macaque etc.</li>
<li>Wildlife Protection Act, 1972 has been modified from time to time</li>
<li>It is further complemented by other Acts viz. Indian Forest Act, 1927, Forest(Conservation) Act, 1980, Environment (Protection) Act, 1986 and Biological Diversity Act, 2002 and the Scheduled Tribes and Other Traditional Forest Dwellers (Recognition of Forest Rights) Act, 2006</li>
</ul>
</div>
<div style='float: right; width:50%;'>

<!--### <Success>Biodiversity Conservation Efforts at International level</Success>-->

<!--</div>-->
<!--<div style='float: right; width:50%;'>-->
	<!--![image](https://temp-public-img-folder.s3.ap-south-1.amazonaws.com/sathee.prutor.images/subject-images/iitpal/image/biology-class-12-unit-15-chapter-03-ecology-biodiversity-and-conservation-lecture-3_3-fy-txkagkui-22.jpg)-->
	<!--![image](https://temp-public-img-folder.s3.ap-south-1.amazonaws.com/sathee.prutor.images/subject-images/iitpal/image/biology-class-12-unit-15-chapter-03-ecology-biodiversity-and-conservation-lecture-3_3-fy-txkagkui-23.jpg)-->

<h3 id="successbiodiversity-conservation-efforts-at-international-levelsuccess"><Success>Biodiversity conservation efforts at international level</Success></h3>
<div style='float: left; width:100%;font-size:28px; '>
<table>
<thead>
<tr>
<th></th>
<th></th>
</tr>
</thead>
<tbody>
<tr>
<td>Ramsar convention</td>
<td>The ramsar convention is an international treaty for the conservation and sustainable use of wetlands. It is also known as the convention on wetlands. It is named after the city of ramsar in iran, where the convention was signed in 1971</td>
</tr>
<tr>
<td>Convention of International Trade in Endangered Species (CITES)</td>
<td>It is an international agreement endorsed by 118 countries in 1973 to ensure that international trade in specimens of wild animals and plants does not threaten their survival</td>
</tr>
</tbody>
</table>
</div>
<div style='float: right; width:0%;'>
<p><img alt="image" src="https://temp-public-img-folder.s3.ap-south-1.amazonaws.com/sathee.prutor.images/subject-images/iitpal/image/biology-class-12-unit-15-chapter-03-ecology-biodiversity-and-conservation-lecture-3_3-fy-txkagkui-22.jpg"></p>
<p><img alt="image" src="https://temp-public-img-folder.s3.ap-south-1.amazonaws.com/sathee.prutor.images/subject-images/iitpal/image/biology-class-12-unit-15-chapter-03-ecology-biodiversity-and-conservation-lecture-3_3-fy-txkagkui-23.jpg"></p>
</div>

<!--### <Success>LETS DISCUSS!</Success>-->

<h3 id="successlets-discusssuccess-1"><Success>Let’s discuss!</Success></h3>
<div style='float: left; width:100%;font-size:30px;text-align:left;'>
<p><strong>Question.</strong> What is a Tree Line?</p>
<p><strong>Answer.</strong> When we go up an altitude, beyond a particular height no trees are found and the vegetation comprises only of    shrubs and herbs. The altitude beyond which no tree is seen is known as tree line.</p>
<p><strong>Question.</strong> Can you give any one example, based on your day-to-day observations, showing how loss of one species may lead to extinction of another.</p>
<p><strong>Answer.</strong> Plant-pollinator relationship. Example-Fig-wasp</p>
</div>

<h3 id="successlets-discusssuccess-2"><Success>Let’s discuss!</Success></h3>
<div style='float: left; width:100%;font-size:30px;text-align:left;'>
<p><strong>Question.</strong> Do you think that more biodiversity enhances the chances of a community to remain stable or resilient under changing   environmental situations. How?</p>
<p><strong>Answer.</strong> Yes, David Tilman’s experiment using outdoor plots has given some evidence to show that with more species diversity, there is less fluctuation in productivity per year. They also show more resilience and biomass generation</p>
</div>

	<!--![image](https://temp-public-img-folder.s3.ap-south-1.amazonaws.com/sathee.prutor.images/subject-images/iitpal/image/biology-class-12-unit-15-chapter-03-ecology-biodiversity-and-conservation-lecture-3_3-fy-txkagkui-168-2907.6.jpg)-->

<h3 id="successlets-evaluatesuccess"><Success>Let’s Evaluate</Success></h3>
<div style='float: left; width:100%;font-size:30px;text-align:left;'>
<p><strong>Question.</strong> What are the major causes of species losses in a geographical region?</p>
<p><strong>Answer.</strong> ‘The Evil Quartet’ is the sobriquet used to describe the four major causes of Biodiversity loss -</p>
<ol>
<li>Habitat loss and fragmentation</li>
<li>Overexploitation</li>
<li>Alien species invasion</li>
<li>Co-extinction</li>
</ol>
</div>

<h3 id="successlets-evaluatesuccess-1"><Success>Let’s Evaluate</Success></h3>
<div style='float: left; width:99%;font-size:28px; '>
<p><strong>Question.</strong> Among the ecosystem services are control of floods and soil erosion. How is this achieved by the biotic components    of the ecosystem?</p>
<p><strong>Answer.</strong> Control of flood is carried out by retaining water and preventing run off of rain water. Litter and humus of  plants helps in retaining the water which percolates down</p>
<p>Control of soil erosion is done by roots of plant which hold the soil particles</p>
</div>

<h3 id="successlets-evaluatesuccess-2"><Success>Let’s Evaluate</Success></h3>
<div style='float: left; width:99%;font-size:28px; '>
<p><strong>Question.</strong> Can you think of a situation where we deliberately want to make a species extinct? How would you justify it?</p>
<p><strong>Answer.</strong> We are trying to eradicate disease causing organism. For ex. Small pox virus, polio</p>
<p>As these organisms are not essential components of any ecosystem, losing one or few such organism would not affect    the functioning of an ecosystem much.</p>
</div>

	<!--![image](https://temp-public-img-folder.s3.ap-south-1.amazonaws.com/sathee.prutor.images/subject-images/iitpal/image/biology-class-12-unit-15-chapter-03-ecology-biodiversity-and-conservation-lecture-3_3-fy-txkagkui-180-3061.2.jpg)-->

	<!--![image](https://temp-public-img-folder.s3.ap-south-1.amazonaws.com/sathee.prutor.images/subject-images/iitpal/image/biology-class-12-unit-15-chapter-03-ecology-biodiversity-and-conservation-lecture-3_3-fy-txkagkui-183-3112.8.jpg)-->