Environmental Sciences Hot Spots of Biodiversity
Total Page:16
File Type:pdf, Size:1020Kb
Paper No: 03 Biodiversity and Conservation Module: 15 Hot Spots of Biodiversity Development Team Prof. R.K. Kohli Principal Investigator & Prof. V.K. Garg& Prof. Ashok Dhawan Co- Principal Investigator Central University of Punjab, Bathinda Prof. Daizy Batish Paper Coordinator Panjab University, Chandigarh Prof. Daizy Batish Content Writer Central University of Punjab, Bathinda Dr. Sunil Mittal, Content Reviewer Central University of Punjab, Bathinda Anchor Institute Central University of Punjab Paper 03 Biodiversity and Conservation Environmental Sciences Hot Spots of Biodiversity Description of Module Subject Name Environmental Sciences Paper Name Biodiversity and Conservation Module Hot Spots of Biodiversity Name/Title Module Id EVS/BC-III/15 Pre-requisites 1. To understand the concept biodiversity Hot spots 2. biodiversity Hot spots at Global Level 3. Biodiversity Hot spots in India Objectives 4. Protecting and maintaining biodiversity hotspots 5. Keywords Paper 03 Biodiversity and Conservation Environmental Sciences Hot Spots of Biodiversity Module 15: Hot Spots of Biodiversity Biodiversity Species hotspot richness Level of Endemic threat to richness species Biodiversity hotspots are areas that support natural ecosystems that are largely intact and where native species and communities associated with these ecosystems are well represented. They are also areas with a high diversity of locally endemic species, which are species that are not found or are rarely found outside the hotspot. The concept of biodiversity hotspots was given by Norman Myers in two articles ‘’The Environmentalist’’ (1988 & 1990). In 1988 he first identified ten tropical forest ’’hotspots’’ characterized both by exceptional levels of plant endemism and by serious levels of habitat loss. In 1990, Myers added a further eight hotspots, including four Mediterranean type ecosystems. Conservation International (CI) adopted Myers’ hotspots as its institutional blueprint in 1989, and in 1996, the organization made the decision to undertake a reassessment of the hotspots concept. Three years later an extensive global review was undertaken, which introduced quantitative thresholds for the designation of biodiversity hotspots. Paper 03 Biodiversity and Conservation Environmental Sciences Hot Spots of Biodiversity According to CI, to qualify as a hotspot a region must meet two strict criteria: It must contain at least 1,500 species of vascular plants (> 0.5% of the world’s total) as endemics. It has to have lost at least 70% of its original habitat OR It must have 30% or less of its original natural vegetation In 1999, CI identified 25 biodiversity hotspots in the book “Hotspots: Earth’s Biologically Richest and Most Endangered Terrestrial Ecoregions”. Collectively, these areas held as endemics about 44% of the world’s plants and 35% of terrestrial vertebrates in an area that formerly covered only 11.8% of the planet’s land surface. The habitat extent of this land area had been reduced by 87.8% of its original extent, such that this wealth of biodiversity was restricted to only 1.4% of Earth’s land surface. In 2005 CI published an updated titled “Hotspots Revisited: Earth's Biologically Richest and Most Endangered Terrestrial Ecoregions”. Global Biodiversity Hotspots: World Currently, there are 35 Biodiversity Hotspots. Overall, These hotspots once covered 15.7 percent of the Earth's land surface. In all, 86 percent of the hotspots' habitat has already been destroyed, such that the intact remnants of the hotspots now cover only 2.3 percent of the Earth's land surface. The biodiversity hotspots hold especially high numbers of endemic species. Each hotspot faces extreme threats and has already lost at least 70% of its original natural vegetation. Over 50% of the world’s plant species and 42% of all terrestrial vertebrate species are endemic to the 35 biodiversity hotspots. I. Africa A total of 08 Hotspots in African continent hold a diversity of plant and animal life, many of which are found nowhere else on Earth. 1. Cape Floristic Region 2. Coastal Forests of Eastern Africa 3. Eastern Afromontane Paper 03 Biodiversity and Conservation Environmental Sciences Hot Spots of Biodiversity 4. Guinean Forests of West Africa 5. Horn of Africa 6. Madagascar and the Indian Ocean Islands 7. Maputaland-Pondoland-Albany 8. Succulent Karoo II. Asia-Pacific Composed of large land areas as well as islands dotting the Pacific seas, these 14 Hotspots represent important biodiversity. 1. East Melanesian Islands 2. Himalaya 3. Indo-Burma 4. Japan 5. Mountains of Southwest China 6. New Caledonia 7. New Zealand 8. Philippines 9. Polynesia-Micronesia 10. Southwest Australia 11. Forests of Eastern Australia (new) 12. Sundaland 13. Wallacea 14. Western Ghats and Sri Lanka III. Europe and Central Asia From the Mediterranean Basin to the Mountains of Central Asia, these four Hotspots are unique in their diversity. 1. Caucasus 2. Irano-Anatolian 3. Mediterranean Basin Paper 03 Biodiversity and Conservation Environmental Sciences Hot Spots of Biodiversity 4. Mountains of Central Asia IV. North and Central America North and Central America play host to thousands of acres of important habitat. 1. California Floristic Province 2. Caribbean Islands 3. Madrean Pine-Oak Woodlands 4. Mesoamerica V. South America From Brazil's Cerrado to the Tropical Andes, South America has some of the richest and most diverse life on Earth. 1. Atlantic Forest 2. Cerrado 3. Chilean Winter Rainfall-Valdivian Forests 4. Tumbes-Chocó-Magdalena 5. Tropical Andes Hottest hotspots Some hot spots are much richer than others in terms of their numbers of endemics. The analysis so far has considered five key factors: numbers of endemics and endemic species/area ratios for both plants and vertebrates, and habitat loss. These factors do not carry equal weight, so they cannot be combined into a single quantitative ranking. For comparative purposes in qualitative fashion, Hear is a list of eight 'hottest hotspots', which appear at least three times in the top ten listings for each factor. 1. Madagascar 2. Philippines 3. Sundaland 4. Brazil’s Atlantic forests 5. Caribbean island 6. Indo – Burma region 7. Western Ghats & Srilanka Paper 03 Biodiversity and Conservation Environmental Sciences Hot Spots of Biodiversity 8. Eastern arc & coastal forests of Tanzania/Kenya The leaders are Madagascar, the Philippines and Sundaland, appearing for all five factors, followed by Brazil's Atlantic Forest and the Caribbean, appearing for four. Three of these hotspots, Madagascar, the Philippines and the Caribbean, have small areas, which further highlights their importance. The map shows 34 biodiversity hotspots. These are the areas which are suffering biodiversity loss and where attention is needed. Originally Norman Myers gave the twenty-five biodiversity hotspots (green, coded as 1-25) and later nine hotspots (blue, 26-34) added by Mittermeier. http://www.drishtiias.com/upsc-exam-gs-resources-BIODIVERSITY-HOTSPOT Paper 03 Biodiversity and Conservation Environmental Sciences Hot Spots of Biodiversity Megadiverse countries The concept of megadiversity is based on the total number of species in a country and the degree of endemism at the species level and at higher taxonomic levels. The World Conservation Monitoring Centre recognized 17 megadiverse countries in July 2000 including: 1. Australia 6. India 11. Brazil 16. United States 2. The Congo 7. Indonesia 12. Colombia 17. Venezuela 3. Madagascar 8. Malaysia 13. Ecuador 4. South Africa 9. Papua New Guinea 14. Mexico 5. China 10. Philippines 15. Peru This group of countries has less than 10% of the global surface, but support more than 70% of the biological diversity on earth. The concept was first developed by Russell Mittermeier in 1988, as a way to prioritize conservation action. Based on an analysis of primate conservation priorities, he found that four countries accounted for two-thirds of all primate species. The analysis was then expanded to include other mammals, birds, reptiles, amphibians, plants and selected groups of insects. This countries representing majority of tropical rainforests, coral reefs and other priority systems. The results of the assessment were published in the Megadiversity: Earth's biologically wealthiest nations (Mittermeier, Gil and Mittermeier eds. 1997. Cemex, Mexico). Global Biodiversity Hotspots: Asia-Pacific 1. East Melanesian Islands Once largely intact, the 1,600 East Melanesian Islands are now a hotspot due, sadly, to accelerating levels of habitat loss. 2. Himalaya The Himalaya Hotspot is home to the world’s highest mountains, including Mt. Everest. Paper 03 Biodiversity and Conservation Environmental Sciences Hot Spots of Biodiversity 3. Indo-Burma Encompassing more than 2 million km² of tropical Asia, Indo-Burma is still revealing its biological treasures. 4. Japan The islands that make up the Japanese Archipelago stretch from the humid subtropics in the south to the boreal zone in the north, resulting in a wide variety of climates and ecosystems. 5. Mountains of Southwest China With dramatic variations in climate and topography, the Mountains of Southwest China support a wide array of habitats including the most endemic-rich temperate flora in the world. 6. New Caledonia An island the size of New Jersey in the South Pacific Ocean, New Caledonia is the home of no less than five endemic plant families. 7. New Zealand A mountainous archipelago once dominated by temperate rainforests, New Zealand harbors extraordinary levels of endemic species.