Sustaining Biodiversity: The Ecosystem Approach Chapter 6

Sustaining Biodiversity: The Ecosystem ApproachSustaining Biodiversity: The Ecosystem Approach

Chapter 6

Biodiversity - DefinedBiodiversity - Defined

• Speciation – Extinction = Biodiversity– Raw genetic material for further

evolution

SuccessionSuccession

• Highest diversity occurs when there is enough disturbance to prevent the dominant competitors from taking over, but not so much that the community is unable to develop.

Human Activities and BiodiversityHuman Activities and Biodiversity

Habitat Loss and DegradationHabitat Loss and Degradation

Greatest threat to species diversity

“HIPPO”Habitat destruction Invasive speciesPopulation (humans) growthPollutionOver-harvesting

Greatest threat to species diversity

“HIPPO”Habitat destruction Invasive speciesPopulation (humans) growthPollutionOver-harvesting

Rate = 80 million new people/year+ New York City every month+ Germany every year+ United States every 3.7 years

Biodiversity isaffected by humanpopulation sizeand resourceuse

Agriculture Industry

Economic production and consumption Recreation

Global Biodiversity StatusGlobal Biodiversity Status

Forests Grassland

Rainforests Desert

Everything

5% of our virgin forests remain uncut

2% of our native grasslands are left in their native state

15% of our redwood forests are old growth

Less than 50% of our wetlands remain

Open Season On Wetlands Destruction Begins

Menards filling wetlands for new store

Their existence being deemed less important than others…

In Puget Sound, we have lost 70% of our estuaries to farms and development

Over 800 miles of Puget Sound shorelinehas been armed withbulkheads.

Importance of BiodiversityImportance of Biodiversity

• Intrinsic value – right to exist, to have evolved means they have important roles

• Instrumental value – because of their use to us

• Existence value – knowing it exists

• Aesthetic value – wildlife viewing

• Bequest value – willing to pay for its existence

Solutions for Protecting BiodiversitySolutions for Protecting Biodiversity

Types of US Public LandsTypes of US Public Lands

• Multiple-use lands: National Forests; National Resource Lands (BLM)

• Moderately-restricted use lands: National Wildlife Refuges

• Restricted-use lands: National Park System; National Wilderness Preservation System

US Public LandsUS Public Lands

Fig. 11-6 p. 198

Managing US Public LandManaging US Public Land

Conservation biologists support:

• Biodiversity and ecological function

• No subsidies or tax breaks for use

• Public should get fair compensation

• Users held responsible for actions

Developers and Resource Extractors Support:

• Sell public land• Cut funding to

administer lands• Cut old growth

forests• Drill in the Artic

Refuge

Ecological and economic services of forests

Ecological and economic services of forests

Trade-Offs

Advantages

Helps meet country’s timber needs

Cut areas grow back

Keeps lumber and paper prices down

Provides jobs in nearby communities

Promotes economic growth in nearby communities

Disadvantages

Provides only 4% of timber needs

Ample private forest land to meet timber needs

Has little effect on timber and paper prices

Damages nearby rivers and fisheries

Recreation in national forests provides more local jobs and income for local communities than logging

Decreases recreational opportunities

Logging in U.S. National Forestsand other publicly owned lands

*

Clear cutting our forests: Advantages and Disadvantages

Trade-Offs

Clear-Cutting Forests

Advantages

Higher timber yields

Maximum economic return in shortest time

Can reforest with genetically improved fast-growing trees

Short time to establish new stand of trees

Needs less skill and planning

Best way to harvest tree plantations

Good for tree species needing full or moderate sunlight for growth

Disadvantages

Reduces biodiversity

Disrupts ecosystem processes

Destroys and fragments some wildlife habitats

Leaves moderate to large openings

Increases soil erosion

Increases sediment water pollution and flooding when done on steep slopes

Eliminates most recreational value for several decades

Sustainable ForestrySustainable Forestry

• Several methods can be used to sustain harvests and maintain biodiversity

Longer rotations will provide a morestable ecosystem and greater biodiversity

Selective logging leaves habitat,minimizing disturbance and fragmentation

Habitat fragmentation and island biogeography

Leave snags and downed logs for cavity nesting animals

Logging roads like this one have dozens of ditches, culverts and other conduits that dump pollution from clear cut and herbicide-sprayed hillsides directly into streams and rivers.

Recent efforts by the forest industry, the tribes and government agency scientists have worked to lessen theimpacts of logging roads.

Include ecologicalservices in estimatingeconomic value

Rainforests harbor the greatest gene pool in the world. The rainforest has nurtured this "pool" to become home for 170,000 of the world's 250,000 known plant species.

Tropical Deforestation: ConsequencesTropical Deforestation: Consequences

• Rapid and increasing

• Loss of biodiversity

• Loss of resources (e.g., medicines)

• Contributes to global warming

Tropical Deforestation: CausesTropical Deforestation: Causes

• Population growth• Poverty• Environmentally harmful

government subsidies (encourage poor to colonize tropical forests)

• Debts owed to developed countries• Low value of ecological services

Managing and Sustaining National ParksManaging and Sustaining National Parks

• Inadequate protection• Often too small to sustain

biodiversity• Invasions by nonnative species• Too many human visitors• Traffic jams and air pollution• Better pay for park staff

Establishing, Designing, and Managing Nature Reserves Establishing, Designing, and Managing Nature Reserves

• Include moderate to large tracts of land

• Involve government, private sector and citizens

• Biosphere reserves• Adaptive ecosystem management• Protect most important areas (“hot

spots”)• Wilderness areas

Ecological Restoration: Basic PrinciplesEcological Restoration: Basic Principles

• Mimic nature • Recreate lost niches • Rely on pioneer species • Control nonnative species• Reconnect small patches

Protecting Biodiversity in Washington StateProtecting Biodiversity in Washington State

• Governor Locke’s Executive Order• Establishment of the Washington

Biodiversity Council– Develop 30-year comprehensive prioritized

strategy to protect biodiversity– Assess existing and potential landowner

incentive program– Develop public education and a web site– By December 31, 2007

Ecosystem Planning in Washington StateEcosystem Planning in Washington State

• Mitigation “banks”• Growth Management Act Critical

Area Ordinances• CREP and CRP• Marine Protected Areas• Eco-regional Assessments for

Biodiversity