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Sustaining Terrestrial
Biodiversity
Managing and Protecting Ecosystems
The Frontier Worldview Frontier worldview-the idea that
Earth’s resources are inexhaustible and it is there more human’s to conquer it. Contrast to Native American
views that deeply respected the land and its plants and animals
Led to enormous waste of resources because of belief that they were inexhaustible
By 1850 about 80% of land was owned by U.S. government, most taken from Native Americans
By 1900 more than half of U.S. public land was given away or sold cheaply to promote settlement.
Case Study: Yellowstone Wolves
Between 1850 & 1900, 2 million wolves were shot, trapped, and poisoned to keep W. and Great Plains safe for livestock
1973 U.S. Endangered Species Act only 400 wolves remained in lower 48 states.
1974 U.S. Fish and Wildlife Service (USFWS) listed them as endangered.
Case Study: Yellowstone Wolves
Keystone predator: Kept down populations of deer,
moose, and coyote and provided food for scavengers
Populations then rose drastically, devastating vegetation and increasing soil erosion.
1987 USFWS proposed introduction of gray wolves into Yellowstone, which was protested.
1995 caught wolves in Canada and relocated
Presently less damage due to elks and coyotes.
Human Impacts on Terrestrial Biodiversity
Humans have disturbed 50-80% of Earth’s land surface
82% of temperate deciduous forests cleared, fragmented, and dominated for crops and urban development
Tundra, tropical deserts, and land w/ ice are least disturbed b/c harsh conditions and poor soils are unappealing.
Humans ALONE use, waste, or destroy 10-55% of NPP of planet’s terrestrial ecosystems.
Human Impacts on Terrestrial Biodiversity
Global extinction rates of species are at least 100 to 1,000X’s what it was before humans existed Rate currently 1%/year Threats to increase sharply by 2018
Convention on Biological Diversity of the 1992 Earth Summit in Rio was ratified by 178 countries: National surveys of wildlife Establishment of parks and reserves Assessment and protection of endangered species.
Human Impacts on Terrestrial Biodiversity
Both the needy poor and the largest amount of biodiversity that is vanishing is located in developing countries.
We can’t address one without the other.
Projected Status of Biodiversity1998–2018
Critical and endangered Threatened Stable or intact
ANTARCTICA
NORTHAMERICA
EUROPE
AFRICA
ASIA
SOUTHAMERICA AUSTRALIA
PacificOcean
Antarctic Circle
PacificOcean
Tropic of Cancer
Tropic of CapricornIndianOcean
AtlanticOcean
150°90°60°E0°30°W90°120°150°0°
60°
30°N
30°S
60°
Arctic CircleArctic Circle
Human PopulationSize and resource use
Human ActivitiesAgriculture, industry, economic
production and consumption, recreation
Indirect Effects
Direct Effects
Degradation and destruction of natural ecosystems
Alteration of natural chemicalcycles and energy flows
Changes in number and distribution of species
Pollution of air, water, and soil
Climate change
Loss of biodiversity
What Can We Do? Two approaches:
1. Species approach- to protect species from premature extinction
2. Ecosystem approach- protect populations of species and their natural habitats affects all others of ecosystems.
**Notice importance of habitat!
The Species Approach The Ecosystem Approach
Goal
Protect species frompremature extinction
Strategies• Identify
endangered species
• Protect their critical habitats
Tactics
• Legally protect endangered species
• Manage habitat
• Propagate endangered species in captivity
• Reintroduce species into suitable habitats
Goal
Protect populations ofspecies in their naturalhabitats
Strategy
Preserve sufficient areasof habitats in differentbiomes and aquaticsystems
Tactics• Protect habitat areas
through private purchase or government action
• Eliminate or reduce populations of alien species from protected areas
• Manage protected areas to sustain native species
• Restore degraded ecosystems
Conservation Biology Multidisciplinary science
Started in 1970 Use emergency responses to slow down human’s
destruction and degradation of biodiversity Conservationists identify hot spots- most
endangered species-rich systems, and take action. Endemic plants- Those found nowhere else on
Earth.
Public Lands in U.S. >35% of U.S. land is managed by federal
government—More than any other country 73% of federal public lands in Alaska, and 22% in
western states Public lands can be classified into three categories:
Multiple–use lands, which include National Forests (National Forest Service) and National resource lands (Bureau of Land Management);
Moderately–restricted use lands, which include National Wildlife Refuges (U.S. Fish and Wildlife);
Restricted–use lands, which include National Parks (National Park Service), and the National Wilderness Preservation System.
National parks and preserves National forests (and Xs) National wildlife refuges
Public Lands in U.S. National Forest System
Run by U.S. Forest Service (part of Department of Agriculture)
i.e. Hoosier National Forest 155 forests, 22 grasslands Used for logging, mining, livestock farming, oil
and gas extraction and recreation. National Resource Lands
Managed by Bureau of Land Management (BLM) Used for mining, oil and gas, livestock grazing
Public Lands in U.S. National Wildlife Refuges
Managed by U.S. Fish and Wildlife Service (USFWS)
Most protect habitats and breeding areas for waterfowl and big game
Some protect endangered species from extinction
Permitted activities: hunting trapping fishing, mining, logging, and grazing
Public Lands in U.S. National Park System
More restricted use Managed by National Park Service (NPS) 56 major parks, 331 national recreation
areas, monuments, and historic sites. 1,100 all over the world for other
countries’ programs Human activities threaten them due to:
Noise, congestion, eroded trails Off-road vehicles, damage to vegetation Nonnative species introduction Water pollution
Solutions
National Parks
•Integrate plans for managing parks and nearby federal lands
•Add new parkland near threatened parks
•Buy private land inside parks
•Locate visitor paring outside parks and use shuttle buses for entering and touring heavily used parks
•Increase funds for park maintenance and repairs
•Survey wildlife in parks
•Raise entry fees for visitors and use funds for park management and maintenance
•Limit number of visitors to crowded park rangers
•Increase number and pay of park rangers
•Encourage volunteers to give visitor lectures and tours
•Seek private donations for park maitenance and repairs
Public Lands in U.S. National Wilderness Preservation
System Collectively unites all 760
individual wilderness areas. Wilderness zones lie within other
types of public lands and managed by agencies in charge of those lands
Storehouses for biodiversity and centers of natural evolution
Only non-motor sports allowed U.S. Wilderness Act of 1964-
"...lands designated for preservation and protection in their natural condition..." "...an area where the earth and its community of life are untrammeled by man..."
Public Lands in U.S. 3/30/09 Obama signed the Omnibus
Public Land Management Act of 2009 (Public law 111-11) into law which designated 52 new wilderness areas and added acreage to 26 existing areas, a total addition to the NWPS of over 2 million acres.
The most land to go into the system on record was during the Reagan administration in 1984.
Other Types of Reserves Biosphere reserves-
UN Educational, Scientific, and Cultural Organization (UNESCO) created the Man and the Biosphere (MAB) Programme.
Goal: To establish a least one biosphere reserve in each of the earth’s 193 biogeographical zones.
Today, more than 425 exist Have a core area (protected from human
activities) surrounded by buffer zone (sustainable activities and recreation) and a final, outer, transition zone (more intensive but sustainable activities)
Biosphere Reserve
Core areaCore area
Buffer zone 1Buffer zone 1
Buffer zone 2Buffer zone 2
Human settlements
Tourism andeducation center
Research station
Management of U.S. Public Lands Conservation biologists
Protect biodiversity and habitats Users-pay approach All users or extractors of resources should be
responsible for environmental damage. Economists and developers:
Sell public lands to corporations Slash federal funding Repeal or modify Endangered Species Act Wise-use approach- public lands should be managed
wisely and scientifically to provide needed resources
Major Types of Forests Biomes with forests: boreal,
temperate and tropical. Three types of forests1. Old-growth- uncut or
regenerated that hasn’t been seriously disturbed by humans or natural disasters for 200+ years Storehouses of biodiversity b/c
lots of ecological niches 63% of world’s forests Russia, Canada, Brazil, New
Guinea, etc.
Major Types of Forests2. Second-growth- stand of trees from secondary
succession after removal by humans or natural forces Decent biodiversity 22% of all forests
3. Tree plantations (farms)- uniformly aged trees of one species (monoculture) that are harvested by clear-cutting and then replanted Low diversity 20% of all forests
Years of growth30
2515
10
5
Clear cut
Weak treesremoved
Seedlingsplanted
Two Forest Management Systems Even-aged management (industrial
forestry)- maintaining trees in given stand at about same age and size for harvesting Tree plantations replace biodiverse old-growth
or second-growth forests Uneven-aged management- variety of tree
species at many ages and sizes to foster natural regeneration For biodiversity, sustainable production of
timber, wildlife, and recreation.
Harvesting Trees1st Build roads
Habitat fragmentation and biodiversity loss
Increased erosion and sediment runoff
Exposure to pests and nonnative species
Access to miners, farmers, and off-road vehicles
2nd Harvest trees Various methods, such as
selective cutting, shelterwood cutting, seed-tree cutting, and clear-cutting
Old growth
Highway
HighwayCleared plotsfor grazing
Cleared plotsfor agriculture
Harvesting Trees Selective cutting- removing intermediate
age or mature trees in an uneven-aged forest cut singly or in small groups Reduces crowding and encourages growth and
regeneration Protects site from erosion and wind damage High-grading- selective cutting in many tropical
forests to remove only largest and best trees. Many other trees damaged in process due to hanging vines.
Selective Cutting
Harvesting Trees
Shelterwood cutting- removing all mature trees in area in 2-3 cuttings over a certain period of time
Seed-tree cutting- loggers harvest nearly all trees, but leave a few evenly distributed seed-producing trees
Shelterwood Cutting
Cut 1Cut 2
Seed-Tree Cutting
Harvesting Trees Clear-cutting- all trees removed
Shelterwood and seed-tree cutting are forms of this that occur in 2 or more phases
Strip-cutting- clear-cutting variation that provides sustainable timber yield w/o widespread destruction. Less fragmentation
Clear-Cutting
Strip Cutting
Uncut Cut Cut Cut Uncut
6–10 years ago 3–5 years ago1 year ago
Cutting methods video clip
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
Deforestation Deforestation- temporary or
permanent removal of large expanses of forest for agriculture or other uses.
Human activities have reduced Earth’s forest cover by 20-50%
Deforestation is still continuing at an rapid, exponential rate (0.3-0.8%/year), except in most temperate forests in N. America and Europe
Over 4/5 of losses taking place in tropics
Most common use of wood? Fuel!!!!
Biomass as Fuel
Historically, and certainly before the industrial revolution in developed countries, forests were cleared to use the wood for fuel. In 2000, an estimated 1.8 billion
cubic meters of fuelwood were used globally
Deforested trees or charcoal derived from them are used as fuel by many in developing countries today. In tropical locations, 80% of all
wood used goes toward fuel or charcoal production.
Selling charcoal is a source of income for many.
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 burning and tree decay
•Accelerates flooding
Tropical Deforestation Tropical forests:
Cover 6% of Earth’s land area, but once covered at least 2X’s as much, (since 1950)
Contain more than 50% of terrestrial plant and animal species
**Center for Interaction Forestry Research says the rapid spread in cattle ranching is the biggest threat to the Amazon’s tropical forests!
What’s the Problem? Tropical rainforests provide chemicals as
blueprints for making most of world’s prescription drugs!
Clearing of tropical rainforests results in: Loss of natural cloud cover and rainfall that is produced
by the rainforest itself due to transpiration. Fewer trees = less rain in rainforest
CO2 released through burning of the trees as they’re cleared that act as a storehouse for carbon when intact
Positive feedback This affects the climates of the entire world.
Case Study: Brazil Brazil
Contains 40% of world’s remaining tropical forests in Amazon
Without aggressive action may largely disappear in 40-50 yrs
Their Atlantic coastal rainforest is 93% cleared!
Growing of sugar cane for ethanol Soybeans Cattle grazing Timber plantations
Brazil deforestation
The Incredible Neem Tree Broadleaf evergreen member of mahogany family Quickly reforests degraded land (5-7yrs) Grows well in semiarid conditions Provides fuel wood, lumber, and lamp oil Extracts from seeds and
leaves: Fight bacterial, viral,
and fungal infections Contains natural pesticides that kill > 200 insect species Potential for male birth
control pill.
Case Study: Costa Rica
Once covered by tropical forests, but b/t 1963 and 1980, powerful ranching families cleared much of its forest to graze cattle.
Mid 1970’sestablished system of national parks and reserves, consolidated into 8 megareserves
Each has protected inner core surrounded by buffer zones that local people can use.
Eliminated subsidies for converting forests to cattle grazing land
Pays landowners to maintain forests.
Case Study: Costa Rica As part of the U.S. Tropical Forest Conservation
Act, in 2007 the U.S. granted Costa Rica the largest debt-for-nature swap on record at that time. CR owed the U.S. over $90 million. U.S. and two NGO’s (nongovernmental
organizations) contributed $14 million to help pay down $26 million of the loan (at a discounted rate.)
CR reduced their debt and generated money for their environment.
They are required to use the money they would have paid for the loan for forest conservation efforts.
Nicaragua
CostaRica
Pacific Ocean
Panama
Caribbean Sea
Peninsula Osa
Pacifico Central
CordilleraVolcanica Central
Bajo Tempisque
Arenal
GuanacastleLlanuras deTortuguero
La Amistad
Reducing Deforestation and Degradation
Protect most diverse andendangered areas
Educate settlers about sustainableagriculture and forestry
Phase out subsidies that encourageunsustainable forest use
Add subsidies that encouragesustainable forest use
Protect forests with debt-for-natureswaps, conservation easements,and conservation concessions
Certify sustainably grown timber
Reduce illegal cutting
Reduce poverty
Slow population growth
Reforestation
Rehabilitation of degradedareas
Concentrate farming andranching on already-clearedareas
RestorationPrevention
Solutions
Sustaining Tropical Forests
Logging
Removal of trees for timber, paper, and other goods
Deforestation is just to get rid of the trees.
2/3 wood consumed in U.S. wasted (how?)
Big debate on logging in National Forests
Trade-Offs
Advantages Disadvantages
Logging in U.S. National Forests
Helps meet country’s timber needs
Cut areas grow back
Keeps lumber and paper pricesdown
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 forestsprovides more localjobs and incomefor local communities thanlogging
Decreasesrecreationalopportunities
How To Slow Logging? Decrease pressure to harvest
trees Make paper from tree-free fibers,
which are agricultural residues left over from crops
Use fast-growing crops such as kenaf (kuh-NAHF) and hemp
Kenaf needs fewer pesticides b/c outer covering insect-proof
Needs less fertilizerit’s a nitrogen fixer
Breakdown of fibers easier less energy and fewer chemical to make the paper
Fires and Forests3 types of forest fires:1. Surface fires- burn undergrowth and leaf litter on
floor. Can kill seedlings, but usually spares mature trees Most animals escape
Benefits: Burn away flammable ground material preventing more
destructive fires Release valuable nutrients from undergrowth Stimulates germination of certain seed trees, such as
sequoia and jack pines Helps control pathogens and insects
Surface fire
Fires and Forests2. Crown Fires- start on ground, but then
burn whole trees, leaping from treetop to treetop. Occur where there hasn’t been surface fires in
a long time b/c of built up undergrowth Destroys vegetation, kills wildlife, increases soil
erosion, and burns human structures.
3. Ground fires- fires burn decomposed leaves underground May smolder a long time before detected.
Crown fire
Reduction of Fires Prevention
Require burning permits and close parks during periods of drought
Educate public (i.e. Smokey Bear) Prescribed burning
Controlled ground fires to prevent build up Severe fires threaten 40% of all forest lands
through buildup from past fire prevention programs, increased logging leaving behind debris, and greater public use.
2003 Healthy Forest Initiative Law- timber companies allowed to cut down medium and large trees for 10 years in return for clearing smaller, fire prone trees and underbrush.
Pests in the Forests Emerald ash borer
Exotic, invasive, transported in campfire wood and lumber—some states are quarantined
Larvae feed on trees, stopping their ability to transport nutrients
Tens of millions of ash trees destroyed.
Bagworm Look very similar to pine cones Native pest Attack 100’s of types of trees.
Pine shoot beetle Introduced here in the U.S., and China has
suffered extreme loss of pine trees Attacks new shoots of pine trees,
stunting growth.
Price Tag of Ecological Services Researchers claim the
economic value of long-term ecological services from natural capital of forests is much greater than their short term economic gains
World’s forests provide us with $4.7 trillion/year (1/10 of all good and services of the entire world in 2004.)
What are some of these services?
Forests play a various important ecological roles:Regulate the flow of water
Slow runoff and continual recharge of groundwater and streams, reduce soil erosion and stream sediments
Influence climateincrease local precipitation and lower local temperatures
Vital to carbon cycletake up 90% of carbon fixed by terrestrial ecosystems
Provide wildlife habitatAccording to one calculation a typical tree provides
$196,250 worth of ecological benefits in its lifetimeoxygen, air purification, soil fertility and erosion control, water recycling and humidity control, wildlife habitat
Ecological Importance of Forests
Managing Forests More Sustainably
Harvesting no faster than replenished Reduce road building Protecting old-growth and second-growth
forests and their biodiversity No fragmentation Use selective or strip-cutting Let trees fall and decompose to return
nutrients Include the economic value of forests’
ecological services in price of lumber Certification of sustainably grown timber
Forest Stewardship Council (FSC) Home Depot, Lowes, Andersen, etc. all
participate to guarantee they get supplies from sustainably managed forests.
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
Current Forests in the U.S.
Forests cover more area now (30%) than in 1920! Good news!
More wood grown than cut, and we’ve set aside large areas of protected forests.
Since 1960’s, increasing area of old-growth and second-growth clear cut and replaced with tree plantations. Bad news!
5 Basic Principles of Restoration Most of the damage we have inflicted on
nature is at least partially reversible. Mimic nature! Recreate important ecological niches that have
been lost (i.e.reclaiming industrial areas (brownfields))
Rely on pioneer species, keystone species, and ecological succession to facilitate the process.
Control or remove harmful nonnative species Reconnect small patches to form larger ones
and create corridors where existing patches are isolated.
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