ecological hotspots observed and predicted loss of biodiversity over the years = sixth extinction ...
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Ecological HotspotsEcological Hotspots
Observed and predicted loss of biodiversity over the years = sixth extinction
Loss of biodiversity permanent Conservation biology therefore very important Identification of areas under sever threat of
permanent loss “Hotspots” origin
Evolution of the term: HotspotEvolution of the term: Hotspot Norman Myers-first to develop concept Geographical regions that deserved conservation
priority High numbers of endemic (rare) species in
relatively small areas First 10 hotspots were identified-all tropical
rainforest, plants were indicators for diversity Myers then added a further 8 hotspots
(Mediterranean-type ecosystems added) High species number or high degree of endemism
or under huge threat or combination of factors
Evolution of the term:Hotspot (Cont.)Evolution of the term:Hotspot (Cont.) A consequent analysis resulted in 25 hotspots A minimum number of plant species was required to
be analyzed Two criteria: endemism and degree of threat Not just “pristine” vegetation included-fragmented
vegetation included Mammal, bird, reptile and amphibian endemism and
diversity patterns also analyzed Hotspots covered much more diverse terrestrial
ecosystems A further 9 hotspots has been added but is currently
still being peer-reviewed
The 34 Terrestrial HotspotsThe 34 Terrestrial Hotspots
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The 34 Terrestrial Hotspots (Cont.)The 34 Terrestrial Hotspots (Cont.)1) Atlantic Forest
2) California Floristic Province
3) Cape Floristic Province
4) Caribbean Islands
5) Caucasus
6) Brazilian Cerrado
7) Central Chile
8) Coastal Forests of Eastern Africa
9) East Melanesian Islands
10) Eastern African Afromantane
11) Guinean Forests of West Africa
12) Himalayas
13) Horn of Africa
14) Indo-Burma
15) Irano-Anatolia
16) Japan
17) Madagascar and Indian Ocean Islands
18) Madrean Pine-Oak Woodlands
19) Maputaland-Pondoland-Albany
20) Mediterranean Basin
21) Mesoamerica
22) Mountains of Central Asia
23) Hengduan Mountains of Southwest China
24) New Caledonia
25) New Zealand
26) Philippines
27) Polynesia-Micronesia
28) Southwest Australia
29) Succulent Karoo
30) Sundaland
31) Tropical Andes
32) Tumbès-Chocò-Magdalena
33) Wallacea
34) Western Ghats and Sri Lanka
The 11 Marine HotspotsThe 11 Marine Hotspots
Major limitation to present hotspot analysis Lack of marine realm-purely terrestrial based Study of marine ecosystems based on coral reefs Hotspots located entirely within tropics Study presented not yet comprehensive Research is still on going Although many marine hotspots extend from
terrestrial hotspots=extension
The 11 Marine Hotspots (Cont.)The 11 Marine Hotspots (Cont.)
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The 11 Marine Hotspots (Cont.)The 11 Marine Hotspots (Cont.)
1) Philippines2) Sundaland Islands3) Wallacea4) Gulf of Guinea 5) Southern Mascarene Islands6) Eastern South Africa7) North Indian Ocean8) Southern Japan, Taiwan and Southern China9) Cape Verde Islands10) Western Caribbean11) Red Sea and Gulf of Aden
Tropical RegionsTropical Regions
More specifically tropical forests-renowned for housing the most biologically diverse ecosystems
Occurs between the Tropic of Cancer and Tropic of Capricorn
Share characteristics: climate, precipitation, canopy structure, complex symbiotic relationships
Stable climate Canopy-provides array of niches Holds up to 50% of planet’s species
Tropical Regions-High DiversityTropical Regions-High Diversity
“Latitudinal gradient in species diversity”-increases from poles to equator
Hypotheses: energy/climate based hypotheses and historical/evolutionary base hypotheses
Energy/climate-species based–energy and climate stability hypothesis
Historical/evolutionary based- historical changes and evolutionary rate hypothesis
These hypotheses do however have critiques and need further research to be fully accepted
Other hypotheses do exist This latitudinal gradient is also observed in the marine
realm
High Concentration of Hotspots in High Concentration of Hotspots in Equatorial RegionsEquatorial Regions
High diversity compared to temperate and polar regions-latitudinal gradient hypothesis
High degree of endemism in tropical regions Restricted to relatively small land areas Most tropical regions are under sever threat-mainly due to
social and economical issues Severe habitat loss and destruction Tropical forests once covered 12% of Earth's surface-now
reduced to a mere 5% (maybe even less) Vanishing at disturbingly high rates Therefore most of world’s hotspots found within tropical
regions
Distribution of Endemic (rare) Terrestrial Distribution of Endemic (rare) Terrestrial Species and Freshwater Fish-PlantsSpecies and Freshwater Fish-Plants
Tropical Andes Hotspot contains 15 000 endemic plant species
Sundaland Hotspot also contains 15 000 endemic plant species
Together these hotspots harbor nearly 14% of all vascular plants found on the planet
Cape Floral Kingdom contains the world’s greatest concentration of non-tropical endemic plant species
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biodiversityhotspots.org/xp/Hotspotsbiodiversityhotspots.org/xp/Hotspots
Distribution of Endemic (rare) Terrestrial Distribution of Endemic (rare) Terrestrial Species and Freshwater Fish-MammalsSpecies and Freshwater Fish-Mammals
Sundaland hotspot contains the highest number of endemic mammals-172 species, 17 genera
Madagascar and Indian Ocean Islands hotspot houses 144 endemic mammals species- world's leader in endemic primates houses 5 endemic lemur families
Wallacea hotspot – 127 endemic mammal species
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Distribution of Endemic (rare) Terrestrial Distribution of Endemic (rare) Terrestrial Species and Freshwater Fish-BirdsSpecies and Freshwater Fish-Birds
Tropical Andes hotspot harbors 579 endemic bird species
This hotspot contains all or parts of 21 different Endemic Bird Areas
This high degree of endemism does not compare to any other area in the world
Wallacea hotspot –262 endemic bird species which is astonishing because of its relatively small land
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Distribution of Endemic (rare) Terrestrial Distribution of Endemic (rare) Terrestrial Species and Freshwater Fish-ReptilesSpecies and Freshwater Fish-Reptiles
Caribbean Islands hosts the largest number of endemic reptiles-469 species
Two examples of entirely endemic genera (both snakes) include: Tropidophis sp.(all 26 species endemic) and Alsophis sp.(all 13 species endemic)
The Madagascar and Indian Ocean Islands harbors 367 reptile species and is a major center of chameleon diversity
biodiversityhotspots.org/xp/Hotspotsbiodiversityhotspots.org/xp/Hotspots
Distribution of Endemic (rare) Terrestrial Distribution of Endemic (rare) Terrestrial Species and Freshwater Fish-Amphibians Species and Freshwater Fish-Amphibians
and Freshwater Fishand Freshwater Fish
The Tropical Andes hotspot is the most significant area in the world concerning amphibian diversity as it hosts 980 species of which 670 are endemic
The Mesoamerica hotspot contains 358 endemic amphibian species
The Eastern Afromontane hotspot, where the Great Rift lakes reside, is home to 617 endemic freshwater fish
The Indo-Burma hotspot houses 553 endemic freshwater fish species, 30 endemic genera and 1 endemic family
ThreatsThreats Social and economic threats=habitat loss
and degradation Major cause-exponential human population
growth Increase in foreign debt loads Decrease funds available for conservation Poverty Over hunting and illegal pet trade
Threats (Cont.)Threats (Cont.) Human impact overwhelming Pollution Introduction of invasive alien species Unsustainable use and management of
biodiversity (commercial exploitation) Climate change-global warming Global warming most probably the most
enveloping threat as it has the ability to affect areas out of range of humans
Future predictions state that hotspots could lose between 39-43% of biodiversity
Lack of efficient practical protection
Threats (Cont.)Threats (Cont.) Marine hotspots have specific threats Destructive fishing methods Over exploitation of fish stocks (unsustainable
use) Pollution from urban and agricultural runoff Pollution from sediment logging Live fish trade Oil spills from tankers Coastal and agricultural development
ConservationConservation Priority-identification of regions under severe threat
of extinction which is why hotspots originated Protection of areas through establishment of
reserves, national parks, botanical gardens, heritage sites, wildlife refuges, etc…
Incentive measures are essential for conservation Regulations and market based tools are also used Increase in new conservation tools and conservation
professionals promote action against biodiversity loss
Unique projects- Working for water Ecotourism-mutually beneficial