Sustaining Biodiversity: Sustaining Biodiversity: The Ecosystem ApproachThe Ecosystem Approach

Chapter 8Chapter 8

Sections 1-4Sections 1-4

Key ConceptsKey Concepts

Human impacts on biodiversityHuman impacts on biodiversity

Public lands and their use Public lands and their use

Use and management of forest resourcesUse and management of forest resources

Temperate Temperate and Tropical and Tropical DeforestationDeforestation

Problems associated with parksProblems associated with parks

Establishing and managing natural reservesEstablishing and managing natural reserves

Protecting and sustaining aquatic biodiversityProtecting and sustaining aquatic biodiversity

Importance of ecological restorationImportance of ecological restoration

Sustaining the EarthSustaining the Earth’’s biodiversitys biodiversity

Part 1

Part 2

Reintroducing Wolves to Reintroducing Wolves to Yellowstone (1995)Yellowstone (1995)

Why wolves were killedWhy wolves were killed- - 2 million killed 1850 - 1900 2 million killed 1850 - 1900 to to ““make the west safe for livestock and big-game animalsmake the west safe for livestock and big-game animals””

Wolf protection Wolf protection 1974 listed as endangered species1974 listed as endangered species

Ecological importanceEcological importance- - Keystone predator- culled Keystone predator- culled herds of bison, elk, caribou and mule deer, keep coyote pop low, …herds of bison, elk, caribou and mule deer, keep coyote pop low, …

Yellowstone controversyYellowstone controversy- - ranchers, hunters, ranchers, hunters, miners all opposedminers all opposed

Importance of biodiversityImportance of biodiversity- - ecological success- ecological success- willow & aspen re-growth in riparian areas, more beavers, elk willow & aspen re-growth in riparian areas, more beavers, elk carcasses feed grizzlies, coyote population reduced, squirrel carcasses feed grizzlies, coyote population reduced, squirrel & fox pop increase = more food for eagles & hawks& fox pop increase = more food for eagles & hawks

Fig. 8-1, p. 154

Human Impacts on BiodiversityHuman Impacts on Biodiversity Human Human ““footprintfootprint””

Disturbing the landDisturbing the land- - humans have disturbed humans have disturbed

50 - 83% of Earth50 - 83% of Earth

Destruction of wetlandsDestruction of wetlandshalf worldhalf world’’s wetlands lost in past 100 yrss wetlands lost in past 100 yrs

DeforestationDeforestation

Aquatic biodiversityAquatic biodiversity- - 27% coral reefs severely damaged- 27% coral reefs severely damaged- 75% fish are fished at or above limit75% fish are fished at or above limit

Premature extinctionsPremature extinctions- - current extinction rate likely 1,000 - 10,000 times current extinction rate likely 1,000 - 10,000 times greater than before humansgreater than before humans

Fig. 8-2, p. 155

Stepped Art

Fig. 8-3, p. 156

The Ecosystem ApproachThe Species Approach

Tactics• Protect habitat areas through

private purchase or government action

• Eliminate or reduce populations of nonnative species from protected areas

• Manage protected areas to sustain native species

• Restore degraded ecosystems

Tactics• Legally protect

endangered species

• Manage habitat

• Propagate endangered

species in captivity

• Reintroduce species

into suitable habitats

StrategyPreserve sufficient areas of habitats in different biomes and aquatic systems

Strategy

• Identify endangered species

• Protect their critical habitats

Goal

Protect populations of species in their natural habitats

Goal

Protect species frompremature extinction

Human Human Impacts on Impacts on

BiodiversityBiodiversity

Natural Capital Degradation: OrangutansNatural Capital Degradation: Orangutans

< 20,000 Organutans left- disappear at a rate >2,000 per year

Natural Capital: Scarlet Macaw Natural Capital: Scarlet Macaw

Fig. 8-5, p. 157

Types of US Public LandsTypes of US Public Lands(35% of US is public land)

Multiple-use lands:Multiple-use lands: National Forest System; Natural National Forest System; Natural Resource Lands (BLM)Resource Lands (BLM)

Moderately restricted-use lands:Moderately restricted-use lands: Natural Wildlife Refuges Natural Wildlife Refuges

Restricted-use lands:Restricted-use lands: Natural Park System; Natural Natural Park System; Natural Wilderness Preservation SystemWilderness Preservation System

What percent of U.S. land is What percent of U.S. land is federally-owned public land?federally-owned public land?

a. 35%

b. 7%

cc. 55%

d. 3%

e.e. 0%0%

Fig. 8-6b, p. 158

National parks and preserves National forests (and Xs) National wildlife refuges

US Federal Public LandsUS Federal Public Lands

Managing US Public LandsManaging US Public Lands principles of public land useprinciples of public land use

ConservationistsConservationists DevelopersDevelopersProtecting biodiversity is a primary goalProtecting biodiversity is a primary goal

No subsidies or tax breaks for use of No subsidies or tax breaks for use of resourcesresources

Public should get fair compensation for Public should get fair compensation for useuse

Users are responsible for environmental Users are responsible for environmental damagedamage

Alternative views from developers and Alternative views from developers and industryindustry

Sell public lands / resources @ less Sell public lands / resources @ less than market valuethan market value

Slash funding for regulation Slash funding for regulation

Cut old growth forests in national Cut old growth forests in national forests and replace with tree plantationsforests and replace with tree plantations

Open all public land to oil, mining, off-Open all public land to oil, mining, off-roading and commercial developmentroading and commercial development

Eliminate Nat. Park Service, mine Eliminate Nat. Park Service, mine without royalties, repeal Endangered without royalties, repeal Endangered Species Act, …Species Act, …

Which of the following is a Which of the following is a majormajor problem of U.S. national parks?problem of U.S. national parks?

a. wildfires

b. too much land area to manage

c. Popularity

d. lack of management plans

e.e. attack from vicious wildlife on attack from vicious wildlife on humanshumans

It is permissible to trap It is permissible to trap animals in most national animals in most national

wildlife refuges.wildlife refuges.a. True a. True

b. False b. False

The National Wilderness Preservation The National Wilderness Preservation System forbids the introduction of:System forbids the introduction of:

a. roads b. fishing c. camping d. sailboats e. APES students

Arctic National Wildlife RefugeArctic National Wildlife Refuge(CNN Video) (CNN Video) 2 min2 min

Types of ForestsTypes of Forests

Old-growthOld-growth- - not seriously disrupted for at least several hundred not seriously disrupted for at least several hundred yearsyears

Second-growth Second-growth - results from secondary succession - results from secondary succession

Tree plantation or tree farm Tree plantation or tree farm - - managed tract of uniformly managed tract of uniformly

aged trees of one or two species. Clear cut when commercially valuable, then aged trees of one or two species. Clear cut when commercially valuable, then replanted.replanted.

Fig. 8-7, p. 160

Support energyflow andchemical cycling

Reduce soilerosion

Absorb andrelease water

Purify water

Purify air

Influence localand regionalclimate

Storeatmosphericcarbon

Providenumerouswildlife habitats

Fuelwood

Lumber

Pulp to makepaper

Mining

Livestock grazing

Recreation

Jobs

Major Services of Forests Major Services of Forests

Forests

Natural Capital

Ecological Services

Economic Services

Ecological services of world’s forests valued at $4.7 trillion per year

Value of ecological services much greater than value of economic services

>>>Much greater than

Types of Forest ManagementTypes of Forest Management Even-aged managementEven-aged management (industry forestry) trees maintained @ (industry forestry) trees maintained @

about same age and size- simplified tree plantation- 1-2 fast-growing species about same age and size- simplified tree plantation- 1-2 fast-growing species harvested on rotation cycle.harvested on rotation cycle.EX: EX: Clear cuttingClear cuttingEX: EX: Seed tree methodSeed tree method: : In the seed-tree method, 2-12 seed trees per acre (5-30/ha) are In the seed-tree method, 2-12 seed trees per acre (5-30/ha) are left standing in order to regenerate the forest. left standing in order to regenerate the forest. EX: EX: Shelter wood methodShelter wood method: : The method's objective is to establish new forest The method's objective is to establish new forest reproduction under the shelter of the retained trees.reproduction under the shelter of the retained trees.

Rotation cycles:Rotation cycles: 25-30 years (temperate),25-30 years (temperate), 6-10 years (tropical)6-10 years (tropical)

EX: EX: Strip cuttingStrip cutting

Uneven-aged managementUneven-aged management- - variety of species w/ range of ages & variety of species w/ range of ages & sizes. Goals: biodiversity, sustainable high quality timbersizes. Goals: biodiversity, sustainable high quality timberEX: EX: Selective cuttingSelective cutting

Sustainable management Sustainable management intensive management of as little as 20% of intensive management of as little as 20% of worldworld’’s forests could meet current and future demand for commercial wood / s forests could meet current and future demand for commercial wood / fiberfiberEX: EX: Combine aspects of a number of these management techniquesCombine aspects of a number of these management techniques..

Tree Plantation Tree Plantation

Fig. 8-8, p. 160

Degradation of Forests from Degradation of Forests from Logging RoadsLogging Roads

Increased erosion and sediment runoffIncreased erosion and sediment runoff

Habitat fragmentationHabitat fragmentation

Biodiversity lossBiodiversity loss

Pathways for pests, diseases, and invasive speciesPathways for pests, diseases, and invasive species

More accessible for humansMore accessible for humans

HighwayCleared plotsfor grazing

Cleared plotsfor agriculture

Fig. 8-10b, p. 161

Degradation of Forests Degradation of Forests

Degradation Degradation from Clear-cut from Clear-cut

Logging Logging

Fig. 8-12, p. 163

Fig. 8-13, p. 163

Trade-Offs

Clear-Cutting Forests

Advantages Disadvantages

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

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

Tradeoffs of Clear-cutting Forests Tradeoffs of Clear-cutting Forests

© 2006 Brooks/Cole - Thomson Fig. 8-14, p. 164

Natural Capital Degradation

Deforestation

• Decreased soil fertility from erosion

• Runoff of eroded soil into aquatic systems

• Premature extinction of species with specialized niches

• Loss of habitat for migratory species such as birds and butterflies

• Regional climate change from extensive clearing

• Releases CO2 into atmosphere from burningand tree decay

• Accelerates flooding

Harmful Effects of Deforestation Harmful Effects of Deforestation

Deforestation has all of the following Deforestation has all of the following effects effects exceptexcept::

a. increase in soil fertility. b. regional climate change. c. flooding. d. extinction of species with specialized niches. e. increase in soil erosion.e. increase in soil erosion.

© 2006 Brooks/Cole - Thomson Fig. 8-15, p. 164

Solutions

Sustainable Forestry

• Grow more timber on long rotations

• Rely more on selective cutting and strip cutting

• No clear-cutting, seed-tree, or shelterwood cuttingon steeply sloped land

• No fragmentation of remaining large blocks of forest

• Sharply reduce road building into uncut forest areas

• Leave most standing dead trees and fallen timber for wildlife habitat and nutrient recycling

• Certify timber grown by sustainable methods

• Include ecological services of trees and forests inestimating economic value

Sustainable ForestrySustainable Forestry

Conserves biodiversity, water & soil resources

Surface and Crown Forest FiresSurface and Crown Forest Fires

Fig. 8-16, p. 166

Ground fire = underground surface fire, common in northern peat bogs

Minimizing Forest Damage from FireMinimizing Forest Damage from Fire

Prescribed burningPrescribed burning- - reduce underbrushreduce underbrush

Allow small fires in National Parks, forests & Allow small fires in National Parks, forests & wilderness to burn wilderness to burn (if people & property not threatened) (if people & property not threatened)

Defensible space- Defensible space- clear 200 feet around buildingsclear 200 feet around buildings

Effects of the Healthy Forests InitiativeEffects of the Healthy Forests InitiativeTimber Co. allowed to take large/medium trees in Nat. Forests if Timber Co. allowed to take large/medium trees in Nat. Forests if they clear away smaller, fire-prone trees- criticized by fire they clear away smaller, fire-prone trees- criticized by fire scientists (large tree most fire resistant, logging creates slash)scientists (large tree most fire resistant, logging creates slash)

Healthy Forests Initiative Healthy Forests Initiative (CNN Video) (CNN Video)

Read more about this!

Managing US National ForestsManaging US National Forests Status of US forests- Status of US forests- 30% of USA forested, more wood grown than cut30% of USA forested, more wood grown than cut

more forests now than in 1920 (old growth forests decreasing)more forests now than in 1920 (old growth forests decreasing)

Importance of national forestsImportance of national forests

Management of forestsManagement of forests

Lost revenue from timber salesLost revenue from timber sales-- timber sales from US federal land lost timber sales from US federal land lost taxpayer money in 97 of past 100 yearstaxpayer money in 97 of past 100 years

Controversies of logging national forestsControversies of logging national forests- 10x more $ and 7x more jobs - 10x more $ and 7x more jobs added to economy by using national forests for recreation, hunting & fishing added to economy by using national forests for recreation, hunting & fishing

Tree-free fibers and paper- Tree-free fibers and paper- agricultural residues, kenaf & industrial hempagricultural residues, kenaf & industrial hemp

Fig. 8-17, p. 168

Trade-Offs

Advantages Disadvantages

Logging in U.S. National Forests

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

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 ForestsLogging in U.S. National Forests

KenafKenaf

Fig. 8-18, p. 169

Holds potential to greatly reduce pressure to cut trees for paper

End Part 1