1. Threats to Biodiversity & Restoration Ecology

2. Considerations about Biodiversity
Biodiversity is linked to ecosystem variability
The more variable ecosystems we have the greater biodiversity will be on Earth A B
Ecotones;
Have increased biodiversity
Edges;
Have increased biodiversity

3. Habitat Loss Natural Sources Human Activities Volcanic eruptions
Wildfires
Droughts
Severe storms (hurricanes)
Deforestation
Draining wetlands
Damming rivers

4. Deforestation in the Tropics
Deforestation occurs when forests are logged for timber or cleared for agricultural use
Tropical forests cover 7% of Earth’s land, but they contain about half of all the species on Earth
Tropical rainforests often have biodiversity hotspots
What can you infer about the bar graph?

5. Deforestation in Canada
Canada has a vast boreal plains ecosystem stretching across Manitoba, Saskatchewan and Alberta
This ecosystem is home to more species of breeding birds than any other forest ecosystem in North America
From forests decreased by up to 55%
The number of bird species declined from 105 in 1987 to only 67 in 1995

6. Wetlands and their importance
Areas of land that are covered by water
Cover about 6% of Earth’s surface
Wetlands provide habitat for many organisms
Wetland plants filter sediment and pollution from water

7. Canadian Wetlands 24% of the world’s wetlands are in Canada
Most wetlands are in Manitoba and Ontario
They cover about 14% of Canada’s total land area

8. Alien Species
Are species introduced to new parts of the biosphere from other places
They are also called introduced species or non-native species or exotic species
They usually arrive by accident in shipments of foods and other goods
They are harmless or beneficial most times

9. Invasive Species
Invasive species are alien species which can take over the habitat of native species or invade their bodies
Many alien species invade aquatic ecosystems through ballast water

11. Zebra Mussels
Introduced into the Great Lakes through the ballast water in the 1980s
Zebra mussels are native to Asia
Shrimp-like crustaceans have declined since then, because they feed on the same food as the Zebra mussels
As the number of crustaceans have declined, so have the numbers of fish

12. Round Gobies in the Great Lakes
The round goby from Asia now lives in the Great Lakes, where it competes with native fish for spawning areas
The round goby is also known to eat the eggs of native fish

13. Overexploitation
Overexploitation is the use or extraction of a resource until it is depleted
It can lead into the disappearance of a species
Examples include the Passenger pigeon, the Yellowfish tuna, and the Atlantic cod

14. The Passenger Pigeon
The Passenger pigeon disappeared in the early 1900s due to overhunting
The population of Passenger pigeons was once about 5 billion

15. The Yellowfish Tuna & the Atlantic Cod
The Yellowfish tuna and the Atlantic cod numbers have been reduced by 90% due to overfishing

16. Can salmon help to keep forests healthy?

17. Connectivity Across Ecosystems
Up to 70% of Nitrogen in organisms that live in the BC forests come via the salmon from the Pacific Ocean
Such nutrients help to increase biodiversity in the forest
Areas without salmon have lower biodiversity than in areas with salmon
Overfishing and habitat destruction from logging and dam construction has resulted into the decline of the salmon population

18. Extinction of Species
Occurs when death rate is higher than birth rate over an extended period of time
Background extinction happens over long periods of time. Ecosystems change gradually
Mass extinction happens relatively rapidly as ecosystems change suddenly e.g. dinosaurs

19. Plants at Risk in Ontario
Extirpated: Local extinction, species exists elsewhere
Endangered: risk of becoming extinct
Threatened: vulnerable to endangerment

20. Biodiversity Crisis?
Ecologists estimate that the current rate of extinction is times higher than a normal background rate
It appears that biodiversity crisis has resulted from the action of humans
Such actions include deforestation, habitat destruction, air and water pollution

21. Environmental Stewardship
Environmental stewardship is the idea that all humans are responsible for looking after a huge piece of property that belongs to all living things; the biosphere
Some ecosystems might be more vulnerable than others, and become unsustainable in less time

22. Restoration Ecology
Is the renewal of degraded or destroyed ecosystems through active human intervention
E.g. Don valley Brick Works

23. Restoration Methods; reforestation
Reforestation is the re-growth of a forest through natural processes or through planting seeds/trees

24. Wetland Restoration
Process by which a wetland is returned to its natural state in terms of soil quality, water coverage, type of plants grown, and habitat
Water control structures are used by wetland conservationists to help restore and maintain water levels

25. Controlling Alien Species
Biocontrol; the use of one species to control the population growth or spread of an undesirable species e.g. Gypsy moths and indiscretus
Chemicals; the use of chemicals to control the population of an undesirable species e.g. rats which reduced the colony of ancient murrelets

26. Bioremediation vs Bioaugmentation
Bioremediation involves the introduction of living plants, fungi or bacteria to detoxify soils, or to break down oil from oil spills
Bioaugmentation is the use of organisms to add essential nutrients to depleted soil
E.g. clover planted to replenish nitrogen levels in soil

27. The Future of Restoration Ecology
Restoration and enhancement of sustainable ecosystem would be essential especially when we consider our exponential population growth and our negative impact to ecosystems
The Alberta Tar Sands involves almost total destruction of huge areas of boreal forests and the production of toxic waste
The scale of this project promises to be a major challenge for restoration