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Potential conflicts. I am going to assign you all a role, you must look up what your opinions on the ANWR development would be You will then have to talk to other people and complete your conflict matrix You can use pages 96-97 to help. Complete a conflict matrix of the various views.
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Potential conflicts I am going to assign you all a role, you must look up what your opinions on the ANWR development would be You will then have to talk to other people and complete your conflict matrix You can use pages 96-97 to help
Biodiversity distribution BIODIVERSITY UNDER THREAT Learning intention: To understand the distribution of biodiversity and what a hotspot is
What does this map tell us about the global distribution of biodiversity?What is the link?
Global variations in biodiversity • 70% of the world’s species is found in just 12 countries It is not surprising that new species have been discovered in the tropical rainforests of Papua New Guinea because biodiversity is greatest in the tropics and declines as you move towards the poles
Determining factors What factors determine the distribution of biodiversity? Climate Endemism Human activity
Global variations in biodiversity • Tropical rainforests contain over 50% of the world’s species in just over 7% of the world’s land area • 80% of all insects • 90% of all primates • Brazil, Indonesia and Madagascar contain over 55% if the world’s mammals • Tropical America has about 85 000 species of flowering plants, compared with about 11 300 in Europe
Global variations in biodiversity Biodiversity is low where there are climatic extremes Biodiversity is greatest in the tropics Biodiversity is generally greatest in the southern hemisphere
What makes a hotspot? I would like you to discuss what you think the term ‘biodiversity hotspot’ means What criteria makes a hotspot?
Hotspot criteria 1. Species richness 2. Number of endemic species 3. Number of species at risk
Biodiversity hotspot A biodiversity hotspot is an area containing a huge number of species, a large percentage of which are endemic. Hotspots have been described as ‘the most remarkable places on Earth and the most threatened’. They cover less than 2% of the Earth’s surface yet they contain 44% of the world’s plant species and 35% of its animal species.
Biodiversity hotspots Initially 25 terrestrial hotspots, recently updated to include marine reserves so there are now 34 Terrestrial hotspots cover 1.4% of the earth’s surface, but contain 44% of the world’s plants and 35% of the world’s animal species Marine hotspots are essentially coral reef areas in the tropics Terrestrial and marine hotspots are often adjacent to each other
Biodiversity hotspots The location of hotspots does not correlate exactly with the location of greatest biodiversity, e.g. France Tropical distribution of both types of hotspot is due to an absence of limiting factors, which allow maximum primary productivity NET PRIMARY PRODUCTIVITY – rate at which all the plants in an ecosystem produce net useful chemical energy (how quick plants grow)
What makes a hotspot Using the information provide I would like you to complete a case study about your hotspot You will then have to share this with others
Advantages of hotspots Has ensured that the ‘best bits’- areas with the highest levels of biodiversity, substantial levels of endemism (unique/rare species) are conserved and protected. Areas under threat are commonly in the tropics and in developing countries where conservation costs are much lower (cheap labour) – idea of value for money. Hotspots now covers marine area under threats in addition to terrestrial ecosystems
Disadvantages of hotspots Even with the additions of marine hotspots under 2% of the earth and 0.017% of oceans are protected by this approach The distribution of areas protected is very uneven. Most hotspots lie in the tropics e.g. rainforests. Many ecosystems such as Tundra, Taiga and Temperate Forest are not included. Huge areas of the world are not covered including many areas under great threat e.g. Arctic Ocean, or many outstanding smaller regions such as Galapagos . These are not protected because they do not meet all three criteria to be a hot spot. Polar bears subsequently face extinction. Hotspots tend to follows protectionist approach. This entails removing people and their activities from areas under threat. This has occurred in tropical countries where indigenous people have been forced off their land in favour of creating big reserves.
Exam Question A) explain the distribution of the world’s terrestrial and marine hotspots in the fig. below. (10)