biodiversity and conservation. by Srimaathangi
- 1. SEMINAR TOPIC: LOSS OF BIODIVERSITY- CAUSES AND CONSERVATION(IN-SITU AND EX- SITU) NAME: SRI MAATHANGI S. ROLL NO:2023BOT021 BHARATHIDASAN UNIVERSITY Subject: ECOLOGY AND PHYTOGEOGRAPHY
- 2. 3 MAJOR ASPECTS: LOSS OF BIODIVERSITY CAUSES OF BIODIVERSITY CONSERVATION OF BIODIVERSITY
- 3. BIODIVERSITY LOSS ◦ It refers to reducing any aspect of biological diversity, destruction, or manual removal; it can refer to many scales. From global extinction to population extinctions, it is resulting in decreased total diversity at the same scale(IPBES). ◦ Natural extinction: with the change in environmental conditions, some species disappear and others, more adapted to changed conditions, take their place. This loss of species occurred in the geological past at a very slow rate. ◦ Mass extinction: it is the dying off or extermination of a large number of species to catastrophes. ◦ Anthropogenic extinction: it is the extermination of a large number of species directly or indirectly by human activities like habitat destruction, over-exploitation, hunting, pollution, etc.
- 4. 32% AMPHIBIANS 31% GYMNOSPERMS 23% MAMMALS 12% BIRDS SPECIES FACING THREAT OF EXTINCTION 1st Qtr 2nd Qtr 3rd Qtr 4th Qtr Presently some 15,500 species world wide are facing the threat of extinction. They includes in the pie chart:
- 5. CAUSES OF BIODIVERSITY ◦ Under the natural process of evolution the unfit species becomes extinct due to natural selection, but in the last couple of centuries, the earth’s biological diversity has been threatened by various human activities. ◦ According to estimates, tropical deforestation may result in the loss of 5- 15% of species the year 2020(WRI,1989). ◦ More than 1,00,000 species become extinct each year due to biotic and abiotic factors. But today, an even more dangerous and devastating threat the global warming caused by greenhouse gases.
- 6. MAJOR CAUSES HABITAT LOSS AND FRAGMENTATION OVER- ECPLOITATION ALIEN SPECIES INVASIONS CO-EXTINCTIONS
- 7. HABITAT LOSS AND FRAGMENTATION: When people cut down trees, fill a wetland, plow a grassland, or burn a forest; the natural habitat of a species is changed and destroyed. Large habitats are broken into small fragments resulting in habitat loss and fragmentation. OVER-EXPLOITATION: Humans have always depended on nature for food and shelter, but when “need” turns to “greed”, it leads to over-exploitation like deforestation and over- harvesting. ALIEN SPECIES INVASIONS: New species entering a geographical region are called exotic or alien species. When these species are introduced deliberately they cause the destruction of native species through interactions. CO-EXTINCTIONS: There are many obligate associations amongst different species. When one of them becomes extinct, the plant or animal species associated with it also becomes extinct.
- 8. BIODIVERSITY CONSERVATION ◦ Conservation of biological diversities is the protection of plant and animal species from the over-exploitation and destruction of habitats and forests. ◦ Biodiversity plays a major role in many ecosystem services that nature provides. They include oxygen, pollination, aesthetic pleasure, flood and erosion control. ◦ There are many species which has an intrinsic value,though it may not be of direct use to us, it is therefore, our moral and ethical duty not to destroy them, instead we should take care of their well being so as to pass the rich biological legacy to future generations. ◦ THERE ARE TWO BROAD CATEGORIES OF CONSERVATION.
- 9. IN-SITU CONSERVATION ◦ In-situ conservation emphasizes the protection of the whole ecosystem, therefore its biodiversity at all levels is protected. It means we save the entire forest to save a single tiger. ◦ There are two strategies for in-situ: Hotspots: this concept was developed to designate priority areas for this type of conservation. Biodiversity hotspots in India include the Western Ghats, Indo-Burma, and the Himalayas. ◦ Protected areas: these are areas dedicated to the protection and maintenance through legal or other effective means. This network broads into sacred groves, biosphere reserves, and national parks and wildlife sanctuaries. ◦ India has 14 biosphere reserves,90 national parks, and 448 wildlife sanctuaries covering 4.7% of the land surface. ◦ Also there are four sacred groves in India.
- 10. EX-SITU CONSERVATION ◦ In this type of conservation strategy, threatened animals and plants are taken out of their natural habitat and placed in a special setting where they can be protected and given special care. ◦ If an animal or plant is endangered or threatened and needs urgent measures to save it from extinction, this ex-situ is the desirable approach. Ex-situ conservation includes; ◦ Home gardens, seed banks, field gene banks, cryopreservation, botanical gardens, zoological parks, aquaria and wildlife safari parks. ◦ Thus many animals and plants that become extinct are saved and continue to be maintained in these conservating places.
- 11. THANKYOU