l2 2015 location of bio and hotspots

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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)

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