l2 2015 location of bio and hotspots
TRANSCRIPT
HOMEWORK
• Complete the A3 sheet
What patterns exist in the global distribution of Biodiversity?
MAP OF GLOBAL BIODIVERSITY
Biodiversity is greatest in the tropics
Biodiversity is generally greatest in the southern hemisphere
Seventy per cent of the world's species is found in just 12 countries: Australia, Brazil, China, Colombia, Costa Rica, Ecuador, India, Indonesia, Madagascar, Mexico, Peru and Democratic Republic of Congo
Biodiversity is low where there are climatic extremes
Mark these features on your top map!
Tropical Rainforests only cover 7% of earths surface yet contain high levels of biodiversity
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’. I.e. threatened areas are ‘hotspots’
Video here:https://www.youtube.com/watch?v=YqUdcW_uNMo
DEVISED HOTSPOT CONCEPT
AIMED TO IDENTIFY PRIORITY AREAS FOR BIODIVERSITY CONSERVATION
ENVIRONMENTAL SCIENTIST
NORMAN MEYERS
NORMAN MEYERS = LEDGEND!!!
HOTSPOT CRITERIA…
1.) THE NUMBER OF SPECIES (SPECIES RICHNESS)
2.) THE NUMBER OF ENDEMIC SPECIES3.) THE NUMBER OF SPECIES AT RISK
Species richness
Endemic richness
Level of threat to species
Biodiversity hotspot
4 CATEGORIES OF HOTSPOT
• Continental Hotspots• Large Island Hotspots• Small Island Hotspots• Marine Hotspots
ATLANTIC FOREST
AUSTRALIA
MADAGASCAR
CORAL REEF
THE DISTRIBUTION OF THE WORLDS HOTSPOTSInitially 25 terrestrial hotspots. Recently updated to include marine hotspots. Now 34 hotspot areas identified.
Terrestrial hotspots cover approximately 1.4% of the earth’s surface. Together they 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 (contain 24% of world’s coral reefs yet cover 0.017% of oceans)
Terrestrial and marine hotspots are often adjacent to each other e.g. Caribbean
The location of hotspots does not
correlate exactly with the location of
greatest biodiversity. E.g. France does not
have a particularly high biodiversity but
yet its southern shores are part of
the Mediterranean Basin Hotspot.
Limiting Factors: The tropical distribution of both types of hotspot is due to an absence of limiting factors which allows maximum primary productivity. In the tropics high temperatures, high humidity, abundant rainfall, and plentiful nutrients all encourage rapid growth of rainforests and reefs
HOTSPOT: BIODIVERSITY PATTERNS
‘Pivotal Areas’ exist where a large number of hotspots exist, important due to variety of species. E.g. Indonesia
Altitude: rapid change in
temp / rainfall over short
distance produces
many different ecosystems all with different
species.
Size and ageSome areas have been undisturbed for centuries and therefore contain a high endism value. E.g. Amazon
Endemism: unique species have evolved on islands. E.g. Lemur in Madagascar here
Perfect conditions for growth: essentially close to the equator where heat, light and moisture are always available and seasonality is minimal; conditions maximise biomass andstratification producing a wide range of niches and continual growth.
ADVANTAGES OF HOTSPOTS1. Has ensured that the ‘best bits’- areas with the highest levels of biodiversity, substantial levels of endemism (unique/rare species) are conserved and protected.
2. 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.
3. Hotspots now covers marine area under threats in addition to terrestrial ecosystems
DISADVANTAGES OF HOTSPOTS1. Even with the additions of marine hotspots under 2% of the earth and 0.017% of oceans are protected by this approach
2. 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.
3. 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.
4. 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.
Where in the world?
Case Study:Cape Floral Kingdom - South Africa
Cape Floral Kingdom or Fynbos is the smallest but the richest hotspot, with highest concentration of plant species,
1,300 per 10,000km.
Here are some of the reasons why its so special …
Intensification of agriculture, destroys natural habitat.
7,700 plant species, 70% of them are endemic
Plants well suited to drought and unusual geology.
Your Turn!
• Create a Dummies Guide to The Location of Biodiversity Hotspots.
• You will need to – Define Hotspots– Assess their merit (i.e. positives and negatives)– Add in a case study of a hotspot (Cape Floral
Kingdom Hot Spot, South Africa)
Dummies Guide to Hotspots
What is a hotspot?
Where are they in the world?
CASE STUDY: Cape Floral Kingdom Hot Spot
Pros Cons