Transcript chapter8_PartII2011short

Sustaining Biodiversity:
The Ecosystem Approach
Chapter 8
Sections 5-8
The Short Version
Tropical Deforestation

Rapid and increasing - 11 football fields per minute lost in 2004

Loss of biodiversity at least half world’s terrestrial species live in tropical
forests

Deforestation for croplands, logging and ranching

Problems measuring deforestation- satellite images difficult, countries
misreport, varying definitions

Causes of tropical deforestation = pop. Growth, poverty, gov. subsidies, debt,
failure to value ecological services

Burning: contributes CO2 to global warming

Possible solutions - prevention & restoration - see next slide
Protecting Tropical Forests
Solutions
Sustaining Tropical Forests
Prevention
Protect most diverse and endangered areas
Restoration
Reforestation
Educate settlers about sustainable
agriculture and forestry
Phase out subsidies that encourage
unsustainable forest use
Add subsidies that encourage
sustainable forest use
Rehabilitation of degraded areas
Protect forests with debt-for-nature swaps,
conservation easements, and conservation
concessions
Certify sustainably grown timber
Concentrate farming and ranching on
already-cleared areas
Reduce illegal cutting
Reduce poverty
Slow population growth
Fig. 8-21, p. 171
Burning of Amazon Tropical Forest
Fig. 8-19, p. 170
Basic and Secondary Causes of the
Destruction of Tropical Forests
•Oil drilling
•Mining
•Flooding from dams
•Tree plantations
•Cattle ranching
•Cash crops
•Settler farming
•Fires
•Logging
•Roads
Secondary Causes
•Not valuing
ecological services
•Exports
•Government policies
•Poverty
•Population growth
•Roads
Basic Causes
Fig. 8-20, p. 170
Global Outlook: Threats to National Parks

Too little protection

Illegal wood collection, logging, poaching, and mining

Too little money to support the parks

Too small to sustain biodiversity

Invasions from nonnative species

Too many visitors to US national parks

Traffic jams and air pollution in US parks

Underpaid park officials

Harm from dirt bikes, dune buggies, and snowmobiles
Establishing, Designing, Protecting
Nature Reserves

Currently 12% of earth’s land is “protected”

Include large to moderate tracts of land

Preserve biodiversity

Involve government, businesses, and private groups

Buffer zone concept: biosphere reserves

Costa Rica’s accomplishments

Adaptive ecosystem management

Emergency action and biodiversity hot spots

Wilderness
Biosphere Reserve
Biosphere Reserve
Core area
Buffer zone 1
Buffer zone 2
Tourism and
education center
Human
settlements
Research
station
Fig. 8-23, p. 174
Biodiversity Hot Spots
Fig. 8-26, p. 176
Animation
Biodiversity hot-spots interaction.
Wilderness Protection in US

Mostly a losing battle

Wilderness Act of 1964

National Wilderness Preservation System

Protected wilderness increased 10 fold since 1970

Most protected areas are small (4.6% of US land is protected as
wilderness)

Only 81 of 233 distinct US ecosystems are protected

Efforts to expand wilderness areas in the US
Ecological Restoration
= “process of repairing damage caused by humans to the biodiversity &
dynamics of natural ecosystems”

Restoration, rehabilitation and replacement

Creating artificial ecosystems
4 Principles of Ecological Restoration:
1.
Mimic nature
2.
Recreate important ecological niches
3.
Rely on pioneer, keystone and foundational species and natural ecological
succession
4.
Control or remove nonnative species

Accomplishments in Costa Rica
Restoration of a Stream Bank
Area restored in 10 years after banning grazing and off-road vehicles.
Fig. 8-28, p. 178
General Patterns of Marine
Biodiversity

Greatest biodiversity in coral reefs, estuaries,
and deep-sea floor

Biodiversity is higher near coasts than open sea

Biodiversity is higher on the ocean bottom than
the surface
Major Human Impacts on Aquatic
Biodiversity

Loss and degradation of habitat is greatest threat

Damage to coral reefs and other habitats

Dredging / trawler operations destroy bottom habitats

Overfishing

Premature extinction
Degradation of the Ocean Floor
Fig. 8-29, p. 179
Why Is It Difficult to Protect Marine
Biodiversity?

Coastal development

Unseen pollution

Lack of protection in international waters

“Tragedy of the Commons”
Protecting and Sustaining Marine
Biodiversity

Protecting endangered and threatened species

Establish large and unpolluted protected areas- marine reserves work.

Integrated coastal management

Protect wetlands

Prevent overfishing

Regulate and prevent pollution
Managing Fisheries
Solutions
Managing Fisheries
Fishery Regulations
Set catch limits well below the maximum
sustainable yield
Bycatch
Improve monitoring and enforcement of
regulations
Use net escape devices for seabirds and sea turtles
Economic Approaches
Sharply reduce or eliminate fishing subsidies
Use wide-meshed nets to allow escape of smaller
fish
Ban throwing edible and marketable fish back into
the sea
Aquaculture
Charge fees for harvesting fish
and shellfish from publicly owned
offshore waters
Restrict coastal locations for fish farms
Certify sustainable fisheries
Depend more on herbivorous fish species
Protected Areas
Establish no-fishing areas
Nonative Invasions
Establish more marine protected areas
Filter organisms from ship ballast water
Rely more on integrated coastal management
Dump ballast water far at sea and
replace with deep-sea water
Consumer Information
Label sustainably harvested fish
Publicize overfished and
Control pollution more strictly
Kill organisms in ship ballast water
Fig. 8-30, p. 181
What Can We Do? Wilson’s Priorities

Preserve world’s biological “hot spots”

Save the old-growth forests

Map world biodiversity so we know what we have

Identify and protect marine “hot spots”

Protect and restore lakes and streams

Ensure the full range of ecosystem types in the conservation strategy

Make conservation profitable

Initiate worldwide ecological restoration projects