Chapter 8

North American Gray Wolf
• Reduced to a few hundred
• Keystone species
• Restoration proposal angered ranchers, hungers, loggers
• 1995, reintroduced in Yellowstone, 136 by
2007
• Positive ripple effect after reintroduction

•
8-1 How Are We Affecting the Earth’s Biodiversity and
Why Should We Protect It?
Concept 8-1A We are degrading and destroying biodiversity in many parts of the world and these threats are increasing.
• Concept 8-1B We should protect biodiversity because it exists and because of its usefulness to us and other species.

Loss of Biodiversity
• Earth’s biodiversity depleted and degraded
–
Wetlands, grasslands & forests
• 83% land surface disturbed
– Antarctica & Greenland

Loss of Biodiversity
• Degradation of aquatic biodiversity
–
50% wetlands (globally)
–
15-35% coral reefs destroyed and damaged
• Ecological fishprint unsustainable
–
200 commercially valuable fish overfished or at their sustainable yield
–
29% collapsed, w/90% in decline
–
Need >2.5x current ocean area
– Japan, Indonesia and China

Lake Victoria
• Lake Victoria has lost their endemic fish species to large introduced predatory fish.

Lake Victoria
• Reasons for loss of biodiversity:
– Introduction of Nile perch.
– Algal blooms from nutrient runoff.
– Invasion of water hyacinth has blocked sunlight and deprived oxygen.
– Nile perch is in decline because it has eaten its own food supply.

Why Protect Biodiversity
• Intrinsic value
–
Value regardless of use to us
• Instrumental value
– Use Value : Usefulness in terms of economic and ecological services.
(farms, crops, fisheries)
• Nonuse values
–
Existence
–
Aesthetic
–
Bequest

Endangered Orangutans

• Concept 8-2 We can sustain forests by recognizing the economic value of their ecological services, protecting old-growth forests, harvesting trees no faster than they are replenished, and making most paper from fast-growing plants and agricultural residues instead of trees.

Forest Services
• Forests 30% of earth’s land surface –
– mostly in the mountains

Types of Forests
• Old-growth forests
–
(primary, ancient, primeval, frontier) diverse
–
150-500+ yrs old
–
22% of forests
• Second-growth forests
– Secondary succession
• Tree plantation
–
Managed, uniform, clear cut, economical, depletes nutrients

Short Rotation Cycle Forestry

Loss of Original Forests
• DEFORESTATION – temporary & permanent
– 46% in 8,000 years, most since 1950
• Most in tropical areas, developing countries
–
–
Crops and cattle
Latin America, Indonesia, Africa
• Estimated loss of 40% intact forests within next 20 years
– Clearing is exponential (0.3-0.8%)

Video: U.S. Forests
Videos/US_Forests.mov

Roads and Forests
• Fragmentation, destruction, and degradation.

Natural Capital Degradation: Deforestation
Fig. 8-6, p. 155

Putting a Price Tag on Nature’s Ecological Services
The long-term health of an economy cannot be separated from the health of the natural systems that support it.
• Estimated value of earth’s ecological services
–
$33.2 trillion per year
–
$4.7 trillion per year for forests
• What services do we need to start factoring into land use?

Good News on Forests
• 2000–2005 net total forested area stabilized or increased
– N. America, Europe, India, China, Turkey & Vietnam
• Most due to tree plantations
– Some secondary succession (cropland & cleared forests)
• BENEFIT
– Wood needs, decreased erosion & nutrient loss, CO
2
• LOSS
– Decreased biodiversity & nutrients

Return of Forests in the United States
• U.S. forests
–
Cover ~30% of land
–
Contain ~80% of wildlife species
–
Supply ~67% of nation’s surface water
• Forest cover greater now than in 1920
• Secondary succession

Return of Forests in the United States
• Second- and third-growth forests fairly diverse
• More wood grown than cut annually
• 40% of forests in National Forest System
– 155 National Forests
• LOSS: transformed into tree plantations
– Julia Hill – “Butterfly” – two years on a platform of California redwood tree

Controversy over the National Forests
• Forest service mandate
– Principle of sustainable yield
• Harvest at replenishing rate
– Principle of multiple use
• Recreation, hunting & fishing in forests = 10x timber revenue
• Timber companies push for tree cutting to be primary goal
•
•
Subsidized by taxpayers money
Timber sales have lost money 97 out of last 100 yrs (cost of roads, timber prep, admin, etc)

Harvest Methods
• Step one – build roads
– Erosion
– Invasive species
– Open up for human invasion
– DISQUALIFY LAND FOR PROTECTION AS WILDERNESS
• Step two – logging operations
– Selective cutting
– Strip cutting
– Clear cutting

Forest Harvesting Methods

Clear-cut Logging
Fig. 8-9, p. 157

Trade-offs: Clear-cutting Forests
Fig. 8-10, p. 157

Forests and Fires
• Surface fires
– Burn undergrowth only
– Cool fire
– Ecological benefits –
– remove flammables, release minerals & seeds (lodgepole), stimulate germination (sequoia/jack pine), control pathogens, post-fire food (deer, moose, elk, quail, etc)
• Crown fires
– Burn the entire tree, hot fire
– Occur in forests with lack of surface fires (buildup)
– Flames leap, are rapid, destructive, kill & erode

Management of Forest Fires
• Fire suppression in all types of forests
– Smokey Bear
• Some forests naturally fire adapted
– Not all fires are bad
– Prescribed fires
– Native Americans

Management of Forest Fires
Restoration of fire’s natural role:
• Allow fires to burn
•
• 60 m buffer zone around homes (thinning)
Healthy Forests Restoration Act, 2003
–
Allows timber companies to cut med-large trees in return for clearing
–
Exempts thinning projects from environmental review
–
Paid for by taxpayers – may increase damage

Forest Fires
• Forest fires have increased – past 15 yrs
– Drying from climate change
– Increases climate change

Certifying Sustainably Grown Timber
• Forest Steward Council certification of forest operations
–
Scientific Certification Systems (SCS)
–
Environmentally sound practices
• Sustainable yield harvest
• Minimal erosion from operations
• Retention of dead wood for wildlife habitat
• Steward of land and water
–
2005 – only 6% certified
• Sweden, Poland, US, Canada

Solutions: Sustainable Forestry
Fig. 8-12, p. 159

Trees and Paper
• Many trees are cut for paper production
• Alternatives
–
Pulp from rice straw and agricultural residues (China)
–
Kenaf (U.S.)
• More paper pulp/land area
• Require fewer pesticides and herbicides http://www.environmentalpaper.org/PAPER-statistics.html

• Concept 8-3 We can reduce tropical deforestation by protecting large forest areas, teaching settlers about sustainable agriculture and forestry, using government subsidies that encourage sustainable forest use, reducing poverty, and slowing population growth.

Tropical Forests
• Cover 6% of earth’s land area (size of US)
– Lost 50% since 1950
• Habitat for 50% of terrestrial plants and animals
– Diversity increases pole to equator
• Vulnerable to extinction – specialized niches
• Rapid loss of 50,000–170,000 km 2 per year
• Imazon (2004) - land occupation/deforestation = 47%

Burning of a Tropical Forest
• Accounts for ¾ greenhouse gas emissions.
Fig. 8-14, p. 160

Destruction of Tropical Forests

Causes of Tropical Forest Deforestation and Degradation
• Population growth and poverty
– Subsistence farming & poor search for land
• Government subsidies
–
–
Reducing cost of harvest and grazing
Gov. gives title to land-clearers to reduce poverty but don’t teach sustainability (Ind, Mex, Brazil)
• International lending agencies encourage development
– Roads, soybeans, coffee, mines, logging, oil, dams
– Africa, Latin America

Effects of Tropical Deforestation
• Fragmentation of remaining patches
– Roads, erosion, toppling
• Remaining forests get drier and may burn
–
Degrades biodiversity
–
CO
2 to the atmosphere
–
Accelerates climate change
–
Converts forest to savannah

Animation: Effects of Deforestation
Animations/effects_deforestation.html

How to Protect Tropical Forests
• Teach settlers to practice small-scale sustainable agriculture
• Harvest renewable resources from the forests
•
•
Debt-for-nature swaps
–
Foreign aid & debt relief to be stewards
Conservation concessions
–
Gov & NPOs give $
• Gentler logging methods

Solutions: Sustaining Tropical Forests
Fig. 8-16, p. 162

Wangari Maathai and Kenya’s Green Belt Movement
• Backyard small tree nursery
• Organized poor women
• Women paid for each surviving seedling planted
–
Breaks cycle of poverty
–
Reduces environmental degradation
–
People walk less distance to get fuelwood
• Sparked projects in 30+ African countries

How Should We Manage and Sustain Grasslands?
• Concept 8-4 We can sustain the productivity of rangeland by controlling the number and distribution of livestock and by restoring degraded rangeland.

Grasslands
• Ecological services
– Soil formation, erosion control, nutrient cycling, carbon storage, maintaining biodiversity
• Second most used and altered ecosystem by humans
– Rangeland - unfenced (temperate/tropical) forage land
• 42% grazed by cattle, sheep, and goats
• Pasture – fenced, managed, sometimes planted
• Grow from the bottom – tops dispensable

Grasslands

Grasslands
• Overgrazing – over carrying capacity
–
–
–
Erosion/compaction,
Invasives (sagebrush, mesquite, cactus, cheatgrass and salt cedar) loss of productivity

Video: Desertification in China
Videos/Desertification_in_China.mov

Manage Rangelands Sustainably
• Practice rotational grazing
– Move fences and confine animals
• Fence out riparian zone areas

Manage Rangelands Sustainably
• Suppress invader plants
– Expensive – herbicides, uproot, trample
• Replant barren soil with seeds
– Expensive – seeds and fertilizer
• Employ controlled burns to control exotic vegetation

San Pedro River Rangelands

8-5 How Should We Manage and Sustain Parks and Nature
Reserves?
• Concept 8-5 Sustaining biodiversity will require protecting much more of the earth’s remaining undisturbed land area, starting with the most endangered biodiversity hot spots.

National Parks
• >1,100 national parks in 120 countries
– Only 1% of parks in developing countries are protected

Problems Protecting National Parks
• Local people invade parks to survive
–
Illegal logging & mining
–
Wildlife poaching
–
Most parks too small to protect large animals
–
Result in invasion of nonnative species

Stresses on U.S. National Parks
• System Est. 1912 by Congress
–
Biggest problem popularity
• Damage from nonnative species
–
Threatened islands of biodiversity

Nature Reserves Occupy a Fraction of Earth
• 12% of earth’s land protected
– Only 5% fully protected (places we don’t want to live) – 95% reserved for human use
• Need for conservation
–
Minimum 20% of land in biodiversity reserves – multiple examples of all biomes

Solutions for Protection
• Requires action – bottom-up political pressure
– We, the people
• Nature Conservancy – world’s largest private system of reserves
– Maintained by private, local citizens
– Opposed by those who say areas contain valuable resources
• Buffer zone Concept
– U.N. Biosphere Reserves (425) – underfunded/staffed
–
Locals to manage reserves and buffer zones

Model Biosphere Reserve
Fig. 8-20, p. 167

Solutions: National Parks
Fig. 8-19, p. 166

Case Study: Costa Rica
• Superpower of biodiversity
– More bird species than all North America
• Government eliminated deforestation subsidies
– Paid landowners to maintain/restore tree coverage
• Goal to make sustainable forestry profitable
– Has gone from highest to lowest deforestation

Costa Rica’s Megareserve Network
• Conserved 25% of its land, 8 megareserves
Fig. 8-21, p. 167

Protecting Wilderness Protects Biodiversity
• Wilderness – land legally set aside/undeveloped
– US Wilderness Society - Minimum size >4,000 km 2
– Otherwise impacted by air, noise, water pollution
• Preserves natural capital
• Centers for evolution
• CRITICS: we cannot use it for its economic value

STEPS: FWS - NPS

STEPS: USFS

Controversy over Wilderness Protection in the U.S.
• 1964 Wilderness Act
–
–
–
–
National Wilderness Preservation System
Increased wilderness 10-fold (1970-2000),
¾ in Alaska, 98% of lower 48 unprotected
Only 4 of 413 wilderness areas >4,000 sq km, 81 of 233 distinct ecosystems
• Roadless Rule protects 400,000 sq. miles
• Pressure from oil, gas, mining, and logging
– 2005 Secretary of Interior removed protection & disqualified cow paths and off-road vehicle trails

Global Biodiversity Hotspots
• 17 megadiversity countries in tropics and subtropics
– Indonesia, Colombia, Mexico, Brazil, Ecuador
• Two-thirds of biodiversity
–
Animations/hotspots.html
Biodiversity hotspots – economically poor/diversity rich

Biodiversity Hotspots in the U.S.
Fig. 8-23, p. 169

• Concept 8-6 Sustaining biodiversity will require a global effort to rehabilitate and restore damaged ecosystems.

Ecological Restoration
• Ecological Restoration – repairing the damage
–
–
Replanting, reclaiming urban (brownfields), restoring wetlands, reintroducing natives/removing invasives & dams effective if GLOBAL & mostly natural (secondary succession)
• Restoration – return to similar state
•
•
•
Rehabilitation – return to functional/useful, not necessarily natural
Replacement – for another ecosystem
Creating artificial ecosystems – e.g. wetlands

Science-based Principles for Restoration
1.
Identify cause of degradation
– Pollution, overgrazing, invasives
2.
Stop abuse by reducing factors
– Remove soil, invasives, cut down on grazing
3.
Reintroduce species if necessary
– Pioneer, keystone, foundation
4.
Protect area from further degradation

Case Study: Ecological Restoration of Tropical
Dry Forest in Costa Rica
• One of world’s largest ecological restoration projects
• Restore a degraded tropical dry forest and reconnect it to adjacent forests
• Involve 40,000 people in the surrounding area – biocultural restoration
• Ecotourism

Will Restoration Encourage Further Degradation?
• It’s cheaper to protect than to restore
• Does environmental restoration suggest any harm can be undone?
• Scientists disagree
–
Restoration badly needed
–
Altered restored site better than no restoration

What Can You Do?
Fig. 8-24, p. 171

• Concept 8-7 We can sustain aquatic biodiversity by establishing protected sanctuaries, managing coastal development, reducing water pollution, and preventing overfishing.

Three Patterns of Aquatic Biodiversity
• Relatively little known about the ocean and freshwater systems
• Greatest biodiversity in coral reefs, estuaries, and deep-ocean floor
• Higher near the coast than in open sea
• Higher in the bottom region of ocean than in surface layer
– More diverse habitats & food sources

Human Impacts on Aquatic Ecosystems
• Ecological Services
– $1.7 trillion/yr
– $3.2 million/minute
• Human activities
– Ocean floor degradation 150x larger than area clear-cut annually
– 75% of most valuable fish species overfished
• IUCN - Likely extinction within our lifetime (more than any other group of species)
– 34% marine fish species
– 71% freshwater species

Effects of Bottom Trawling
• 2004- Scientists attempted high-seas bottom trawling moratorium
– Iceland, Russia, China & S. Korea blocked it
Fig. 8-25, p. 172

Why Is Protection of Marine Biodiversity So Difficult?
• Human aquatic ecological footprint expanding
• Not visible to most people
• Viewed as an inexhaustible resource

Why Is Protection of Marine Biodiversity So Difficult?
• Most ocean areas outside jurisdiction of a country

Solutions for Marine Ecosystems
• Protect endangered and threatened species
–
–
ESA, MMPA, MBTA, The Bald and Golden Eagle Protection Act, the Wild Bird Conservation Act
CITES, International Convention on the Regulation of Whales, and the Convention for the Protection and Development of the Marine
Environment of the Wider Caribbean Region
• Establish protected marine sanctuaries
– Since 1986, IUCN has established 1,300 global MPAs
• Marine reserves – work well and quickly
– Pops double, reproduction triples, adult size grows, diversity increases by 25%
• Integrated coastal management
• Protect existing coastal wetlands

Solutions: Managing Fisheries
Fig. 8-26, p. 173

8-8 Priorities for Protecting Biodiversity
• Map terrestrial and aquatic biodiversity
• Immediately preserve biodiversity hotspots
• Keep old-growth forests intact
• Protect and restore lakes and rivers
• Initiate ecological restoration
• Make conservation profitable