Ecosystems Under Stress

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Ecosystems Under Stress
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Forest Biomes
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Some Forest Facts

• What is a forest? gt 10 canopy cover
• 3.86 billion hectares (2000) (100 m x 100 m,
  10000 m2)
• Deforestation rate 9.4 million hectares/yr
• About 10 of worlds forest protected
• North, Central, South America 16-17!
• New Jersey 464,000 acres out of 4,748,000 acres

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Consequences of Forest Clearing

• Productivity of area reduced
• Nutrients/biomass in tree is gone
• Decreased biodiversity
• Increased likelihood of erosion
• Hydrogeologic cycle changed
• CO2 sink gone
• Lost livelihood for those dependent on forest

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Forest Management (silviculture)

• Trees take a generation or more to mature
• Rotation (which tree gets cut down)
• Even-age vs. Uneven age management (all trees of
  same age cut down versus trees of different age
  cut down)

Even Age Cutting Uneven Age Cutting
Clear-cutting Selective cutting
Fragmentation Maintain ecosystem function
Negative impact on biodiversity Reduced impact
Efficient Sustainable
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Tropical Forests

• Tropical forests are key (biodiversity, climate
  stabilization
• Between 1960-1990 20 of the worlds tropical
  forests were converted to other uses
• No logging in the Philippines - Why?
• Deforestation due to conversion to
  pasture/agriculture
• Often promoted by government policies
• Population issue
• BUT, forests can be a large source of revenue
• No forests left to cut down!

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Encouraging Trends

• Move to sustainable management (6 of tropical
  forests have a management plan)
• Tree plantations in place of field agriculture
  (palm, rubber)
• Extractive resources beyond timber (latex, nuts,
  fiber, fruit)
• Tourism
• Empowering indigenous peoples (not state control)
• Revised World Bank policy
• Sustainable logging only
• Forest Stewardship Council (NGO) promotes
  sustainability through certification (check that
  label)

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Palm Oil Forests

• http//www.youtube.com/watch?vWsLxIdUkGQE