2. Biodiversity
• Biodiversity is the variety of life on
Earth,
• it includes all organisms, species, and
populations;
• the genetic variation among these; and
their complex assemblages of
communities and ecosystems.
3. Levels of biodiversity
1. Genetic diversity is all the different genes
contained in all the living species including
individual plants, animals, fungi, and
microorganisms.
2. Species diversity is all the different species, as
well as the differences within and between
different specie
3. Ecosystem diversity is all the different habitats,
biological communities and ecological processes,
as well as variation within individual ecosystems.
4. Causes of Biodiversity Loss
According to most sources, the major direct
causes of human-induced biodiversity loss
are
1. land-use change (the fragmentation,
degradation or loss of habitats)
2. pollution (air and water)
3. the over-exploitation of natural resources
4. the introduction of non-native (alien or
exotic) species
5. climate change-induced biodiversity
5. LAND USE CHANGES
Changes in landscape due to such activities as
agriculture, urban expansion and transportation
infrastructure are generally major causes of the
loss of biodiversity.
1. Agricultural expansion: (growing food)
• Agricultural expansion in the demand for
compensating meat
• Increased the level of land use change,
converting forests into grazing land.
6. 2. Agricultural expansion: the case of
biofuels
Biofuels which are produced from non-food
feedstock are known as lignocellulosic material.
E.g. wood, wood residues, grass, straw and fast
growing trees. It is important to note that direct
and indirect causes of biodiversity losses from
biofuel production.
7.
8. 1. Direct land use changes
biodiversity loss from degradation of high
conservation value areas (rainforests and
peat lands).
use of pesticides,
genetically modified crops (endanger
wildlife and biodiversity)
2. Displacement effects (also known as
“indirect land use changes or “leakage
effects”).
9.
10. 3. Infrastructure development
• The impact of infrastructural development
includes:
– the direct effects on wildlife by disturbance and
avoidance
– increased hunting activities
– Small scale settlements along roads.
1. Africa commercial logging and timber
production
2. In Latin America and the Caribbean, the
construction of dams, oil and gas pipelines and
new settlements can be seen as a cause of
deforestation.
11. 4. Deforestation
• 31% of the Earth’s land surface,
• Contain more than 1/2 of all terrestrial animal
and plant species (mostly in the tropics)
• Account for more than two-thirds of net primary
production on land (solar energy to plant matter)
• Despite policy efforts on reducing deforestation,
around 13 million hectares of forests continue
to be lost annually.
12.
13. Causes of Deforestation
• including conversion for agricultural uses,
infrastructure development, wood extraction,
agricultural product prices, and a complex set of
additional institutional
• high deforestation rates in Comoros, Burundi, Togo
and Mauritania
• The total size of the deforested area in Brazil and
Indonesia is almost 200 times as large as the area
destroyed in the three countries that experience the
highest deforestation rate.
14. Tropical Rainforest Deforestation
• hosts half of all global biodiversity
• direct cause of biodiversity loss due to the
associated loss of natural habitat.
• second largest source of anthropogenic
greenhouse gas emissions
• contributes significantly to increasing
sedimentation in surrounding coastal areas.
• In South East Asia, sediments reduce coral
growth in one of the most important biodiversity
hot spots.
15. • Brazil, which is estimated to have
around 55,000 species of flora, amounting
to some 22% of the world’s total
• India has about 46,000 and some 81,000
animal species (amounting to some 8% of
the world’s biodiversity), are also under
various pressures, from corporate
globalization, deforestation, etc.
16. Native bananas, palms, climbing
plants and epiphytes and many
invertebrates and birds
Epiphytes (lichens, mosses, ferns and
orchids) use trees for attachment
purposes only, and do no hurt their
host
Forest floor is filled with herbs,
herbivores and carnivores, insects
21. POLLUTION
1. Fresh Water pollution
• Heated water from nuclear power stations for
example and microorganisms from untreated
waste cause serious water pollution.
• Several coastal zones in South- East Asia, for
instance, have developed eutrophication rapidly
resulting in pollution of along others chemical
waste and this may seriously affect tropical coral
reefs.
22. 2. Marine pollution from oil spills
• An approximate 400 gallons of oil a day have
been released into the ocean that poses a
significant threat to wildlife
• toxic and sub-lethal effects on plankton, seabird
drowning or body heat loss following fouling of
plumage by oil
23. Marine Zones Affected by oil
• Open waters are generally considered as less
sensitive to oil spill damage, are typically not used
as habitats, spawning or breeding grounds.
• Coastal waters are the most biologically diverse
marine environments
1. Seabirds breeding and feeding in coastal areas
are faced with a high rate of mortality.
2. Benthic organisms are usually heavily damaged,
as are fish spawning areas and coastal and
seabed vegetation.
24. • Polar region, more specifically offshore sub-
Arctic and Arctic areas temporarily or
permanently covered with sea ice, are subject to
an increasing amount of oil and gas exploration
and sea transport activities.
• Due to the slow growth and decay process
typical for arctic environments, biodegradation
as well as recovery and re-growth of oiled
coastal areas is greatly delayed.
25. UNSUSTAINABLE NATURAL
RESOURCE USE
1. Fisheries
• 90 % of all large fish have disappeared from
the world’s oceans in the past half century, the
devastating result of industrial fishing.
• In the last decade, in the north Atlantic region,
commercial fish populations of cod, hake, have
fallen by as much as 95%,
26. Bluefin tuna (sushi)
• Bluefin tuna disappeared from Danish marine
waters in the 1960s. Now the species could
become depleted throughout the northeast
Atlantic and Mediterranean.
Common cockle
• The common cockle is a species of edible
saltwater clams, a marine bivalve mollusc. It is
commercially overfished in the Netherlands
and the British Isles.
• Declined over 50%
27.
28. 2. Mining
i) Impacts on Fresh water biodiversity
• Minerals that may be present either in the coal or
associated rocks, which causes degradation of
water quality.
• Particulate matter resulting from mining activities
has been shown to be detrimental to local fish
populations.
• Decreased densities of macro invertebrate- and
benthic invertebrate populations have been
associated with increased suspended solids.
29. • Enhanced sedimentation inhibits spawning
and the development of fish eggs and larvae,
as well as smothering benthic fauna (fauna
that inhabit the bottom/beds of rivers and
lakes).
• high turbidity may impair the passage of light,
• E.g. Australian miner spilt approximately 100
million litres of cyanide-contaminated water
into Romanian rivers that killed over one
million kilograms of fish in Hungary.
30. ii) Impacts on marine biodiversity
In many coastal areas oil and gas companies
extract huge quantities of gas and oil, for
instance in the North Sea.
In South East Asia, several oil companies extract
oil from or in the vicinity of the for biodiversity.
Coral reefs can be threatened by oil spills.
31. CLIMATE CHANGE
1) Biodiversity is threatened by human-induced
climate change.
2) of the main threats to biodiversity in the Coral
Triangle and widely reported as the cause of
coral bleaching.
3) desertification may increase in some areas
causing species vulnerable to extinction.
4) Climate change has also been implicated in the
decline of amphibians in tropical forests.
32. INVASIVE ALIEN SPECIES
• Invasive species have been cited as being the
second most important threat to global biodiversity
loss, after land use change.
• More than 80 species have been introduced to the
North Sea.
• These species have an impact on other species
and sometimes reduce the numbers of indigenous
species.
33. Over view of some endangered
species
• The International Union for Conservation of
Nature (IUCN) notes that many species are
threatened with extinction. In addition,
• At threat of extinction are
– 1 out of 8 birds
– 1 out of 4 mammals
– 1 out of 4 conifers
– 1 out of 3 amphibians
– 6 out of 7 marine turtles
34. • 75% of genetic diversity of agricultural crops has
been lost
• 75% of the world’s fisheries are fully or over
exploited
• Up to 70% of the world’s known species risk
extinction if the global temperatures rise by more
than 3.5°C
• 1/3rd of reef-building corals around the world are
threatened with extinction
• Over 350 million people suffer from severe water
scarcity
35.
36. Biodiversity Conservation
Protected areas are an essential part of
conservation programs. To be successful, sites for
protected areas need to be carefully chosen,
ensuring that all regional ecosystems are well
represented.
Market tools, such as direct payments for ecosystem
services or transfers of ownership rights to private
individuals, can provide economic incentives to
conserve biodiversity and to use ecosystem
services sustainably
37. Prevention and early intervention have proven to
be the most successful and cost-effective way of
tackling invasive species
Biodiversity must be integrated into the
agriculture, fishery, and forestry sectors
Strong institutions at all levels are essential to
support biodiversity conservation and the
sustainable use of ecosystems.
38. Informing all of society about the benefits of
conserving biodiversity, and explicitly considering
trade-offs between different options in an
integrated way, helps maximize the benefits to
society.
Ecosystem restoration is generally far more
expensive than protecting the original ecosystem,
but is becoming increasingly important as more
areas become degraded.
