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Chapter 15: Biodiversity and Conservation, , Biodiversity – A vast array of varied species present on the earth, i.e. all living organisms and their, ecosystem together constitutes biodiversity. It was coined by W.G. Rosen, 1985., Levels of biodiversityi., , Genetic diversity- The variations in genetic compositions if individuals., Importancea. It is beneficial for the survival of a species in changing environment., b. It provides reproductive isolation of two different gene pools of related species leading to, speciation.., ii. Species diversity- Diversity of species in a given community or ecosystem., iii. Ecological diversity- It refers to the diversity at ecosystem level (diverse form of ecosystem)., a. Alpha diversity or α-diversity- Diversity within a community (within a habitat)., b. Beta diversity or β- diversity - Diversity between two communities., c. Gamma diversity or γ- diversity- Diversity of different habitats within a large geographical, region., Biogeographical regions of IndiaIndia is one of the 17 megadiversity regions of the world with 8.1% of the genetic resources of the, world. Megadiversity refers to the countries with a high total no. of species including a significant, percentage of endemic species. The concept was first proposed by Russell Mittermeier, 1988. According to, World Conservation Monitoring Centre (WCMC) 17 megadiverse countries., India has sub-divided into ten biogeographical regions-, , Animals are more diverse than plants asi., ii., iii., , They are mobile and to avoid competition they show niche specialization., They adapted themselves to the changing environment by developing various features such as, complex nervous system, protective external layers, etc., They are subjected to less seasonal and more constant environment.

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Patterns of biodiversity:, i. Latitudinal gradient – Distribution of species at different latitude. Species diversity decreases as, we move away from the equator towards the poles., Reason for higher species diversity in tropical region:, a. Tropical regions remained undisturbed for millions of years and thus got enough time for, species diversification while temperate region subjected to frequent glaciations in the past., b. Tropical regions are less seasonal, more constant and predictable., c. Tropical regions receive more solar energy and hence more productivity., ii. Species area relationship- Species richness increased with increasing explored area up to a limit, (Alexander von Humboldt)., The relationship between species richness and area turned out to be a rectangular hyperbola., On a logarithmic scale, the relationship is a straight line described by the equation log S = log C + Z log A, where, S= species richness,, A=Area,, Z= slope of the line (regression, coefficient), C= Y-intercept, , The value of Z is generally in the range of 0.1 to 0.2 except for large continents (0.6-1.2)., , Importance of biodiversity to ecosystem, i., , Stability - A community which is either resilient to natural or anthropogenic disturbance,, resistant to invasion species. Communities with more species tend to be more stable than, those with less species., , ii., , Productivity – Ecosystems with higher biodiversity are more productive then ecosystems, with lower biodiversity., , iii. Ecosystem Health – Biodiversity is essential for maintenance and health of ecosystems, through the occurrence of various checks, controls, negative and positive feed backs, critical, link and keystone species., Rivet popper hypothesis (Paul Ehlrich) - It explained the relationship between, species diversity and ecosystem health. It describes that if a species is continuously removed, from an ecosystem, it leads to extinction of that species. Thus, ecosystem health would be, dangerously affected leading to total collapse of the existing species diversity and, environment.

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Loss of biodiversity, The most serious aspect of the loss of biodiversity is the extinction of species., Extinction is of three typesa. Natural extinction – It is the slow process of replacement of existing species with the, better adapted species due to alternate evolution, changes in environmental conditions,, predators and diseases., b. Mass extinction – Extinctions due to environmental catastrophes. Earth has experienced, five mass extinctions. E.g. Extinction of Dinosaurs, Wooly Mammoth, Mastodon, Giant, sloth, etc., c. Anthropogenic extinction – Extinctions abetted by human activities like settlements,, hunting, overexploitation and habitat destruction. The “Sixth Extinction” presently in, progress by human activities is different from the mass extinction as the current rate of, species extinction are estimated to be 100 to 1000 times faster than the pre-human times., Effects of biodiversity loss, a. Decline in ecosystem productivity., b. Reduced resistance to environmental perturbations like drought., c. Drastic changes in ecosystem process like water use, pest and disease cycles., Causes of Biodiversity loss (Evil Quartet):, a. Habitat Loss and fragmentation- Loss of habitat due to human activities like, deforestation, water pollution etc. Large patches of forest area are cleared (habitat, fragmentation) for establishment of industries, human settlements etc., b. Over exploitation- Over exploitation of natural resources for fulfillment of increasing, human lead to extinction of many species., c. Invasion of alien species- Introduction of alien species also results in either death of species, due to inability to adaptation or proliferate at high rate., e.g. Parthenium, Lantana, Eicchornia, Nile Perch, Clarias gariepinus., d. Co-extinctions- The extinction of one species leads to the extinction of its associated, species due to population interactions., Red Data Book (IUCN Red List) - Listing of organisms based on their severity of threats faced by, them., i. Extinct (EX) - Last individuals of a species has died without doubt., ii. Extinct in Wild (EW) - Organisms which are extinct in wild but their survivor are present, only in cultivation., iii. Critically endangered (CR) - Organism facing high risk of extinction in wild in immediate, future., iv. Endangered (EN) - Organism that are facing high risk of extinction in wild in near future., v. Vulnerable (VU) - Organism that may face extinction risk in wild in medium-term future., vi. Least Concern (LC)-Organism which does not qualify for endangered but may be in, threatened category in future., vii. Near threatened (NT) - Organism that does not qualify for CR and EN, but may be close to, VU., viii. Data deficient (DD) - inadequate information.

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Conservation of biodiversity, Objectives i. To maintain ecological process in their natural states., ii. To preserve the species diversity by germplasm collection and preservation., iii. To utilize nature and natural resources in a sustainable way., Narrowly utilitarian, , Broadly utilitarian, , Ethical utilitarian, , It describes the, economical values of, bioresources., , It describes the ecological services, like O2 production from plant,, pollination and aesthetic values., [Amazon lungs of planet- supply 20%, of total oxygen on earth atmosphere], , It describes the, conservation of intrinsic, value of organisms and, sustainable process for, future generation., , Conservation strategies, There are two types of conservation strategies –, A. In situ conservation- Conservation of wildlife within their natural habitat., E.g. hotspots, protected areas such as sacred groves, National parks, biosphere reserves, and wildlife sanctuaries., a. Biodiversity Hotspots - A biodiversity hotspot is a region with significant number of species, richness, endemism and at the same time most threatened., Criteria of a biodiversity hotspot a. It must contain at least 0.5% of endemic vascular plants., b. At least 70% of its primary vegetation must have lost., Endemic species- The species that are confined to a particular region and are not found, anywhere else are called endemic species., Indian biodiversity hotspotsi., , Indo-Burma Hotspot - Covers tropical Asia, East of Ganges, Brahmaputra, some, parts of NE India., ii. Himalayan hotspot - Cover Northern Pakistan, Nepal, Bhutan, part of NE India., iii. Western Ghats and Sri Lanka- Western Ghats of south western India., *[Sundaland - Nicobar Islands, Singapore, Malaysia.], b. Protected areas i., , Sacred groves- Grove of trees that are of special religious importance to a particular region., Trees were venerated and given total protection by preserving tracts of forest land. E.g., Aravalli (Rajasthan), Sarguja Chhatisgarh), etc., ii. National Parks- A relatively large area where one or several ecosystems are not materially, altered by human exploitation and occupation. E.g. Kaziranga, Manas, Keibul Lamjao, etc.

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iii. Wildlife sanctuary- A protected area mainly for fauna where killing, capturing and hunting, of any species is prohibited except with permission from highest authority. E.g. Manipur, Yaingangpokpi Lokchao., iv. Biosphere reserve - Area of terrestrial and coastal ecosystem meant for conserving and, protecting wildlife in order to promote sustainable development based on local community, efforts. Recognised under UNESCO and MAB programme., Objectives of Biosphere Reservei. To conserve wildlife diversity within natural ecosystems., ii. To safeguard genetic diversity of species., iii. To provide areas for research and monitoring., iv. To provide facilities of educating and training., v. To ensure sustainable use of natural resources., Design of Biosphere reservea. Core Area- Zone which is kept free from human pressure., b. Buffer zone- Zone where education, experimentation research, recreation, cropland,, fisheries, vegetation can perform without hindering the conservation objectives., c. Transition zone- Outermost part which is not delineated. Human settlement,, management of crops can be done here., Function (Importance) a. Restoration function – Helps in restoration of degraded ecosystems and habitats., b. Conservation function- Conservation of genetic resources, species, ecosystems, etc., c. Development function- Culturally, socially and ecologically sustainable economic, development., d. Logistic function- Information exchange through education and research., Biosphere Reserves in NE India (5 out of 18):, i., ii., iii., iv., v., , Nokrek – Meghalaya., Manas – Assam., Dibru-Saikhowa – Assam., Dehang-Dibang - Arunachal Pradesh., Khangchendzonga- Sikkim., National park, , Sanctuary, , a. It is meant for protection of both flora, and fauna., , a. It is meant for protection of only, fauna., , b. Cultivation of land and grazing are not, permitted., , b. Cultivation of land and grazing are, permitted., , c. Forest products are not harvested and, boundary is well demarcated., , c. Forest products are harvested and, boundary is not well demarcated.

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B. Ex situ conservation- Conservation of wildlife outside their natural habitat with conditions similar, to the natural habitat., E.g. botanical garden, zoological parks, arboretum, gene banks, etc., a., , Offsite collection – They are live collections of wild and domesticated species in, botanical gardens, zoological parks, wildlife safari parks, arboretum, etc., , b., , Gene banks – They are type of biorepository that maintain stocks of viable seeds (seed, banks), live growing plants (orchards), tissue culture and frozen germplasm, (cryopreservation) with the whole range of genetic variability (i.e. collection of genetic, variability of all economically important and threatened species)., , In situ conservation, , Ex situ conservation, , a. It is the conservation of endangered, species in their natural habitats., , a. It is conservation of endangered species, outside their natural habitats., , b. The endangered species are protected, from predators., , b. The endangered species are protected, from all adverse factors., , c. The depleting resources are augmented., , c. They are kept under human supervision, and provided all the essentials., , International efforts for Conserving Biodiversity, a. Convention on International Trade in Endangered Species (CITES) – It aims to ensure, that the international trade of wildlife and plant does not threaten their survival and to put ban, on international trade in wildlife., b. World Conservation Union (WCU) – The IUCN seeks to influence, encourage and assist, societies throughout the world to conserve the diversity of natural resources and their, sustainable use., c. United Nations Conference on Environment and Development (UNCED) or Earth, Summit – The Earth Summit at Rio de Janeiro (1992), Brazil promoted Convention on, Biological Diversity (CBD) which was signed by 152 nations. India became a party to this, convention in May, 1994. The various commitments were – Adoption of ways and means to, conserve biodiversity, managing biodiversity for sustainable use and equitable sharing of, benefits from biological and genetic resources. A second World Summit was held in 2002 in, Johannesberg, South Africa that pledged to significantly reduce the current rate of, biodiversity loss at global, regional and local levels by the year 2010. An Earth summit (Rio, +20) was again held in 2012 in Rio de Janeiro to chalk out new strategies for sustainable, development.