Transcript biodiversity

Lecture 5
Biodiversity
Biodiversity
- also called biological diversity
- consists of the forms of life that can best
survive Earth’s conditions
- includes genetic diversity, species
diversity & ecological diversity
Genetic Diversity
- variability in the genetic makeup among
individuals within a single species
Species Diversity
- the
variety of species on Earth
- ~ 1.4 million species described
Ecosystem Diversity
- also
called ecological
diversity
- variety of forests,
deserts, grasslands,
streams, lakes, oceans
and other biological
communities
Aquatic Ecosystems
Aquatic ecosystems include:
- Wetlands
- Mangrove Forests
- Coral Reefs
Wetland
- an area of land covered all or part
of the year with salt water or fresh
water
(excludes lakes, ponds, streams)
Mangrove Forests
- dominated by mangrove trees
- warm tropical climates
- live partly submerged in coastal
wetlands
- habitat for ~ 2,000 species
MANGROVE ROOTS – A Microhabitat
SEAGRASSES
stabilize sediments – provide cleaner waters
absorb nutrient before waters reach coral reefs
food source
habitat (among leaves) and microhabitat (on leaf surface)
Coral Reefs
- found in warm, tropical and subtropical oceans
- coastal, shallow waters
- habitat for many marine plants & animals
- protect shoreline from erosion
POSITION OF CORAL REEFS – EQUATORIAL
REGION (IN GREEN)
• net benefit / yr (World Resources Institute
Global Compilation 2008):
 Worldwide: $US 29.8 billion / yr
 Caribbean: $US 3.1 – 4.6 billion / yr
(largest share from dive tourism)
Importance of Biodiversity
- we
are dependent on the rich variety of genes,
species and ecosystems, for example:
◦ food
◦ medicine
◦ wood
◦ energy
◦ industrial chemicals
◦ raw materials
8 Main Areas of Biodiversity Importance
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Ecosystem Stability
Genetic Reserves
Medicinal
Agricultural
Industrial
Aesthetic
Ethical
Religious / Spiritual
Threatened Species
• any species – animal, plant, fungi etc. – which
is vulnerable to extinction in the near future.
• according to the IUCN (International Union for
the Conservation of Nature) there are three
categories of threatened:
1.
2.
3.
Vulnerable
Endangered
Critically endangered
Threatened Species
Vulnerable: the least critical of the three
categories; species are likely to become
endangered unless circumstances threatening its
survival and reproduction improve e.g. cheetah,
lion, polar bear, komodo dragon
Threatened Species
Endangered: faces a very high risk of extinction
in the near future e.g. blue whale, giant panda,
tiger.
Threatened Species
Critically Endangered: faces an extremely high
risk of extinction in the immediate future e.g.
Mountain Gorilla, Javan Rhino.
Extinction
- complete disappearance of a species
from Earth
- Jamaican Examples:
Jamaica rice rat
Giant yellow galliwasp
Jamaican Parauque
Black-capped Petrel
Examples of Jamaica’s
Threatened Species
Black-billed Parrot
Yellow-billed Parrot
Giant
Swallowtail
Butterfly
Jamaican Iguana
Jamaican Hutia
Jamaican Boa / Yellow
Snake
Characteristics of Endangered Species
• extremely small, localised range
• require a large territory to survive
• living on islands (in isolation)
• low reproductive success
Characteristics of Endangered Species cont’d
• specialised breeding areas
• specialised feeding habits
The 3 Main Human Causes of Extinction
• Habitat Destruction
• Biotic Pollution
• Hunting
Habitat Destruction
- the greatest threat to most wild species
Biotic Pollution
- introduction of foreign or exotic species into
an ecosystem in which it did not evolve
Conservation Biology
- aims to investigate human impact on
biodiversity
- develops practical approaches to prevent
species extinction
- develops compromises between
conservation priorities & human needs
In Situ Conservation
- on-site preservation
- preservation of natural populations in the
wild
- best strategy for the long-term protection
of biodiversity
Ex Situ Conservation
- off-site preservation
- includes:
artificial insemination
in vitro fertilisation
captive breeding programmes
zoos
NATURAL RESOURCE
VALUATION
NATURAL RESOURCE VALUATION
- Process of placing monetary values on
natural environmental resources, their
services, including those that are not
usually accounted for by the market
- Does not value biodiversity for its own
sake but for services provided.
RESOURCE VALUATION cont’d
Services may be estimated in various ways
such as:
- Direct market price.
Decline in the value of fish catch between
1975 and 2000 cost the country an
estimated US$1.6 billion
(Sary, Munro and Woodley, 2003)
RESOURCE VALUATION cont’d
- Damage cost avoided.
• Models have been used to estimate the role of coral
reefs in preventing wave damage.
• The reef in Discovery Bay being severely degraded
would result in 100 structures including two hotels, a
church and an airfield being flooded during a storm
event within a 25 year period.
RESOURCE VALUATION cont’d
- Travel costs.
• Visitors pay money to travel to Jamaica and to stay in hotels.
Damage to beaches would reduce visitation to Jamaica and thus
tourism revenue.
• It has been estimated that at the end of 10 years, current erosion
rates at the beaches in Negril, Montego Bay and Ocho Rios will
cause an annual loss in value of US$19 million.
• If beaches degrade further this value could increase to US$33
million per year.
RESOURCE VALUATION Cont’d
- Costs people are willing to pay for
measures to save a natural resource.
Sewage treatment plants provide the services of
easier waste disposal and cleaner water for swimming
and beach use.
In Barbados a survey revealed that persons living near
where a new sewage treatment plant was to be
constructed were willing to pay US$178 per household
per quarter while those outside the area were only
willing to pay US$11 per household.