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Sustaining Biodiversity


  • pg 1
									Sustaining Biodiversity
    North American Gray Wolf
• Reduced to a few hundred
• Keystone species
• Restoration proposal angered ranchers,
  hunters, loggers
• 1995, reintroduced in Yellowstone, 136 by
• Positive ripple effect after reintroduction
The Gray Wolf
How Are We Affecting the Earth’s Biodiversity
      and Why Should We Protect It?

• We are degrading and destroying
  biodiversity in many parts of the world and
  these threats are increasing.

• 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

• 83% land surface disturbed

• Degradation of aquatic biodiversity

• Ecological fishprint unsustainable
     Why Protect Biodiversity
• Intrinsic value

• Instrumental value

• Nonuse values
  – Existence
  – Aesthetic
  – Bequest
Endangered Orangutans
  How Should We Manage and
       Sustain Forests?
• 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

• Economic services

• Ecological services
          Types of Forests
• Old-growth forests

• Second-growth forests

• Tree plantation
Natural Capital: Forests
Old-growth Forest
Short Rotation Cycle Forestry
      Loss of Original Forests
• 46% in 8,000 years, most since 1950

• Most in tropical areas, developing

• Estimated loss of 40% intact forests within
  next 20 years
Natural Capital Degradation: Deforestation
Science Focus: Putting a Price Tag on
    Nature’s Ecological Services
• Estimated value of earth’s ecological
  – $33.2 trillion per year
  – $4.7 trillion per year for forests

• Need to start factoring values into land use
Roads and Forests
       Good News on Forests
• 2000–2005 net total forested area
  stabilized or increased

• Most of the increase due to tree

• Net loss of terrestrial biodiversity
 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

• More wood grown than cut

• 40% of forests in National Forest System

• Forests transformed into tree plantations
           Harvest Methods
• Step one – build roads
  – Erosion
  – Invasive species
  – Open up for human invasion

• Step two – logging operations
  – Selective cutting
  – Strip cutting
  – Clear cutting
Forest Harvesting Methods
Clear-cut Logging
Trade-offs: Clear-cutting Forests
           Forests and Fires
• Surface fires
  – Burn undergrowth only
  – Cool fire
  – Ecological benefits

• Crown fires
  – Burn the entire tree
  – Hot fire
  – Occur in forests with lack of surface fires
   Management of Forest Fires
• Fire suppression in all types of forests

• Some forests naturally fire adapted

• Restoration of fire’s natural role
Forest Fires
  Certifying Sustainably Grown
• Forest Steward Council (FSC) certification
  of forest operations
  – Environmentally sound practices
  – Sustainable yield harvest
  – Minimal erosion from operations
  – Retention of dead wood for wildlife habitat
• However, the FSC has been under fire for
  certifying areas that are not sustainable-
Solutions: Sustainable Forestry
           Trees and Paper
• Many trees are cut for paper production

• Alternatives
  – Pulp from rice straw and agricultural residues
  – Kenaf (U.S.)
Solutions: Kenaf
         In California, Texas and Louisiana,
         3,200 acres of kenaf were grown in
         1992, most of which was used for
         animal bedding and feed

         Kenaf grows quickly, rising to heights
         of 12-14 feet in as little as 4 to 5
         months. U.S. Department of
         Agriculture studies show that kenaf
         yields of 6 to 10 tons of dry fiber per
         acre per year are generally 3 to 5
         times greater than the yield for
         Southern pine trees, which can take
         from 7 to 40 years to reach
         harvestable size.
 How Serious Is Tropical Deforestation and
        How Can It Be Reduced?
• 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
• slowing population growth
              Tropical Forests
•   Cover 6% of earth’s land area
•   Habitat for 50% of terrestrial plants and animals
•   Vulnerable to extinction – specialized niches
•   Rapid loss of 50,000–170,000 km2 per year
Burning of a Tropical Forest
Destruction of Tropical Forests
   Causes of Tropical Forest
 Deforestation and Degradation
• Population growth and poverty

• Government subsidies

• International lending agencies encourage
                                               Gold Mining
                                                southern Venezuelan lowland tropical rainforest, the
                                                Caura basin has impressive levels of biodiversity -- 2,600
                                                vascular plant species, 168 mammal species, 475 bird
                                                species, 34 amphibian species, 53 reptile species, and
                                                441 species of fish to date -- and stores some 700 million
                                                metric tons of carbon, or about the amount released by
                                                162 million cars in a year.

                                                Area home to indigenous groups -- Ye'kwana, Sanema
                                                and Hoti -- who rely heavily upon local rivers for drinking
                                                water, food, and transportation. isolated parts Amazonia,
                                                these Indians live in mostly traditional ways.
                                   Miners rely heavily on
                                   hydraulic mining
                                   techniques, blasting away
                                   at river banks with high-
                                   powered water cannons
                                   and clearing forests to
                                   expose potential gold-
                                   yielding gravel deposits.

                                   Gold is usually extracted
                                   from this gravel using a
                                   sluice box to separate
                                   heavier sediment and
                                   mercury used to
                                   amalgamate the precious

―Mercury sales are poorly regulated and its use is
widespread…bioaccumulation of mercury in fish poses
health threats to people living downstream.
Fish account for the major share of protein in the diet of
local residents, …Venezuela's Minister of Environment,
said that it will take 300 years to re-plant destroyed forest
in the area and 70 years to decontaminate areas polluted
by the miners.‖          
Effects of Tropical Deforestation
• Fragmentation of remaining patches

• Remaining forests get drier and may burn
  – Degrades biodiversity
  – CO2 to the atmosphere
  – Accelerates climate change
How to Protect Tropical Forests
• Teach settlers to practice small-scale
  sustainable agriculture
• Harvest renewable resources from the
• Debt-for-nature swaps
• Conservation concessions
• Better logging methods
Solutions: Sustaining Tropical Forests
          Individuals Matter:
Wangari Maathai and Kenya’s Green Belt

• Backyard small tree nursery
• Organized poor women
• Women paid for each surviving seedling
  – Breaks cycle of poverty
  – Reduces environmental degradation
  – People walk less distance to get fuel wood
• Sparked projects in +30 African
• 2004 Nobel Peace Price
      Wangari Maathai on Climate Change and
               Copenhagen 2009
 • ―The world hopes that in Copenhagen, governments will
   be guided by the realities of available scientific evidence,
   and act accordingly. I welcome the development of new
   incentive mechanisms, such as reducing emissions from
   deforestation and forest degradation (REDD), which
   should also address degradation of agricultural land.
   REDD would compensate developing countries for
   environmental services provided by indigenous forests
   left standing.‖
 • ―Other mechanisms have been proposed and should be
   considered, including an ―emergency fund‖ by the Prince
   of Wales’ Rainforest Project, which would provide
   payments from public and private sources to countries
   that protect their rainforests. ―
 How Should We Manage and Sustain
    Parks and Nature Reserves?

• Sustaining biodiversity will require
  protecting much more of the earth’s
  remaining undisturbed land area, starting
  with the most endangered biodiversity hot
            National Parks
• >1,100 national parks in 120 countries

• Only 1% of parks in developing countries
  are protected

• Local people invade parks to survive
    Problems Protecting National
• Illegal logging
• Illegal mining
• Wildlife poaching
• Most parks too small to protect large
• Invasion of nonnative species
   Illegal Killing and Trading of
• Poaching endangers many larger
  animals, rare plants
• Over two-thirds die in transit
• Illegal trade $6–$10 billion per year
• Wild species depleted by pet trade
• Exotic plants often illegally gathered
White Rhinoceros Poached for Its Horn
The Value of Wild Rare Species
• Declining populations increase black
  market values

• Rare species valuable in the wild – eco-

• Some ex-poachers turn to eco-tourism
    Rising Demand for Bush Meat
•   Traditional use of bush meat
•   Demand increasing with population growth
•   Increased road access
•   Loggers, miners, ranchers add to pressure
•   Local and biological extinctions
Bush Meat on the Rise
Stresses on U.S. National Parks
• Biggest problem popularity

• Damage from nonnative species

• Threatened islands of biodiversity
       Species Introductions
• Most beneficial – food crops, livestock,
  pest control
• 500,000 alien invader species globally
• 50,000 nonnative species in the U.S.
• The economic toll from damage by
  invasive species—and the costs of trying
  to control them—is enormous: U.S. $137
  billion a year, according to a 1999 Cornell
  University study.
Deliberately Introduced Species
Accidentally Introduced Species
  Case Study: The Kudzu Vine
• Kudzu introduced to control erosion

• Prolific growth

• Uses
  – Asians use powdered starch in beverages
  – Source of tree-free paper
  – Japanese kudzu farm in Alabama
Invasive Kudzu Vine
         Disruptions from Accidentally
              Introduced Species
  • Downside of global trade
  • Argentina fire ant
  • Burmese python
                                      13-foot (4-meter) Burmese python in
                                      Florida's Everglades National Park, the
                                      headless python was found in October
                                      2005 after it apparently tried to digest
                                      a 6-foot-long (2-meter-long) American
Argentina Fire Ant
     Prevention of Nonnative
          Species (1)
• Identify characteristics of successful
• Detect and monitor invasions
• Inspect imported goods
• Identify harmful invasive species and ban
     Prevention of Nonnative
          Species (2)
• ships discharge ballast waters at sea

• introduce natural control organisms of
Characteristics of Successful

                           Fig. 9-12, p. 187
What Can You Do?

                   Fig. 9-13, p. 188
Natural Capital Degradation:
     Off-road Vehicles
   Nature Reserves Occupy a
           of Earth
• 12% of earth’s land protected

• Only 5% fully protected – 95% reserved
  for human use

• Need for conservation
  – Minimum 20% of land in biodiversity reserves
  – Protection for all biomes
      Solutions for Protection
• Requires action – bottom-up political

• Nature Conservancy – world’s largest
  private system of reserves

• Buffer zones around protected areas

• Locals to manage reserves and buffer
Solutions: National Parks
     Case Study: Costa Rica
• Superpower of biodiversity

• Conserved 25% of its land, 8

• Government eliminated deforestation

• Paid landowners to maintain and restore
Model Biosphere Reserve
Costa Rica’s Megareserve
 Protecting Wilderness Protects
• Wilderness

• Minimum size >4,000 km2

• Preserves natural capital

• Centers for evolution
 Case Study: Controversy over
  Wilderness Protection in the
• 1964 Wilderness Act

• Roadless Rule protects 400,000 sq. miles

• Pressure from oil, gas, mining, and logging
  Protecting Global Biodiversity
• 17 megadiversity countries in tropics and

• Two-thirds of biodiversity

• Developing countries economically poor
  and biodiversity rich

• Protect biodiversity hotspots
34 Global Hotspots
Biodiversity Hotspots in the U.S.
  8-6 What Is the Importance of
      Restoration Ecology?
• Concept 8-6 Sustaining biodiversity will
  require a global effort to rehabilitate and
  restore damaged ecosystems.
       Ecological Restoration
• Ecological Restoration

• Restoration

• Rehabilitation

• Replacement

• Creating artificial ecosystems
  Science-based Principles for
• Identify cause of degradation

• Stop abuse by reducing factors

• Reintroduce species if necessary

• 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
   Will Restoration Encourage
       Further Degradation
• Some worry environmental restoration
  suggests 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
 8-7 How Can We Help Sustain
      Aquatic Biodiversity?
• 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
• 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
   Human Impacts on Aquatic
• Destroyed or degraded by human

• Ocean floor degradation 150 times larger
  than area clear-cut annually

• 75% of most valuable fish species
Effects of Bottom Trawling

                         Fig. 8-25, p. 172
   Why Is Protection of Marine
    Biodiversity So Difficult?
• Human aquatic ecological footprint

• Not visible to most people

• Viewed as an inexhaustible resource

• Most ocean areas outside jurisdiction of a
        Solutions for Marine
• Protect endangered and threatened

• Establish protected marine sanctuaries

• Marine reserves – work well and quickly

• Integrated coastal management
Solutions: Managing Fisheries

                          Fig. 8-26, p. 173
     8-8 What Should Be Our
      Priorities for Protecting
• Concept 8-8 Sustaining the world’s
  biodiversity requires mapping terrestrial
  and aquatic biodiversity, protecting
  terrestrial and aquatic hotspots and old-
  growth forests, initiating ecological
  restoration projects worldwide, and making
  conservation profitable.
       Priorities for Protecting
• Map terrestrial and aquatic biodiversity

• Immediately preserve biodiversity hotspots

• Keep old-growth forests intact

• Protect and restore lakes and rivers

• Initiate ecological restoration

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