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
Gwich’in
Environmental
Group
Environme
ntal
Groups
Inupiats
Gwich’in
Alaskan Residents
Inupiats
Arctic Power
Alaskan
Residents
Politicians
Arctic
Power
Politicians
Complete a conflict matrix of the
various views
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?
Is this surprising?
Global variations in biodiversity
 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
 70% of the
world’s
species is
found in
just 12
countries
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
Species
richness
Level of
threat to
species
Endemic
richness
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
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)