Introduction to Tropical forests

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Introduction to Tropical forests
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What are tropical forests?
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What are tropical forests?

• Tropical rainforests drier (deciduous) forests

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Where are tropical forests?
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What area?
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Tropical lowland evergreen r.f.

• What?
• Closed canopy, up to 45 m high
• Evergreen
• Very diverse
• No dominance
• Most (tree) species are rare
• Different tree layers
• Lianas, epiphytes

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Tropical lowland semi-evergr. r.f.

• What?
• Closed canopy, up to 45 m high
• Deciduous and evergreen trees
• Very diverse, but less than evergreen r.f.
• No dominance
• Most (tree) species are rare
• Different tree layers less emergents than in
  evergreen r.f.
• Lianas, epiphytes

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Tropical lowland evergreen r.f.

• Where?
• evenly distributed rain 2000-4000mm
• gt 100 mm per month
• gt 18 degr C monthly temperature
• lt 1200 m altutude

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Tropical forests biodiversity

• Harbour ca. 50 of all species on 7 of land
  surface

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What are threats to tropical forests?
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Threats to tropical forests

• Habitat loss (deforestation) 1-2 / y
• Habitat fragmentation
• Unsustainable use degradation

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Deforestation

• 1990-2000
• FAO 2001

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What happens to forests?

• In mln ha (per y)
• FAO FRA 2000 in SOFO 2001

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Forest loss and gain
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What are solutions to problems?
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What percentage is conserved?
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Protected tropical forests
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Conservation by use or value

• Only 10 in PAs
• Strong and growing demand for timber local use
  of forest products
• Need to conserve forests for
• Carbon sequestration
• Cleaning water
• Preventing erosion
• Great potential for conservation by sustainable
  use of the remaining 90 of forests

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Conservation by use or value

• If without significant biodiversity loss
• Timber
• Non-timber
• And other options
• Ecotourism
• Possible medicinal uses
• Water uses
• Carbon fixation

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What is sustainable use?

• What criteria? Under what conditions?

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Three aspects

• Economically viable
• Socially acceptable
• Ecologically sustainable
• Levels
• Population
• Species
• Ecosystem