Wim Ozinga

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DISPERSAL ASSEMBLY RULES IN DUTCH PLANT
COMMUNITIES ?

• Wim Ozinga
• KUN Prof. Jan M. van Groenendael
• RUG Prof. Jan P. Bakker Dr. Renée M. Bekker
• Alterra Dr. Joop H.J. Schaminée Drs. Stephan
  M. Hennekens

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BACKGROUND

• Disappointing results nature restoration projects
• missing target species
• Constraints on assembly of local communities
• (a)biotic
• Dispersal

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DISPERSAL ASSEMBLY ?

• Importance of dispersal in determining species
  composition
• Species levelinterspecific differences traits,
  trade-offs
• Community level environmental constraints on
  efficiency dispersal vectors (trait-environment
  linkages)
• Landscape level spatial configuration,
  availability dispersal vectors

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TRAIT ENVIRONMENT LINKAGESAPPROACH

• Combination of 2 large databases
• Vegetation database
• Database dispersal traits

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DUTCH VEGETATION DATABASE

• Vegetation relevés (N40.000)
• Synoptic tables
• 170 plant communities (only inland, terrestrial)
• each community species sites occupied
• Ordination
• main environmental gradients
• water availability
• productivity
• light availability

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IRIS DATABASE ON REPRODUCTIVE TRAITS
www.synbiosys.alterra.nl/IRIS

• Focus on long distance dispersal (gt100 m)
• Wind (anemochory)
• Water (hydrochory)
• Herbivores, fur (epizoochory)
• Herbivores, internal (endozoochory)
• Birds (ornithochory)
• Dispersal in time
• Seed longevity

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IRIS DATABASE ON REPRODUCTIVE TRAITS
Example contents
Floating seedlings
T50
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IRIS DATABASE ON REPRODUCTIVE TRAITS
www.synbiosys.alterra.nl/IRIS

• Focus on long distance dispersal (gt100 m)
• Wind (anemochory)
• Water (hydrochory)
• Herbivores, fur (epizoochory)
• Herbivores, internal (endozoochory)
• Birds (ornithochory)
• Dispersal in time
• Seed longevity
• Rough classification species for each dispersal
  vector
• 0 low potential for long distance dispersal
• 1 relatively high ,,

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DATABASE LINKAGES
Species level
Community level
Combination
Dispersal traits
Matrix multiplications
Environment
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DISPERSAL BY WATER
Aquatic
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DISPERSAL BY WIND
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DISPERSAL BY HERBIVORES (FUR)
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DISPERSAL BY HERBIVORES (DUNG)
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SEED LONGEVITY
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SHIFT IN DISPERSAL TRAITS
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DISPERSAL TRAITS WITHIN A COMMUNITYTrait
spectrum broad leafed forest (Carpinetum)
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LIGHT AVAILABILITY POLYCHORY
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CONCLUSIONS

• Spectra of dispersal traits change along main
  environmental gradients (especially along light
  gradient)
• ? dispersal models should include habitat quality
• Within community diversity of dispersal traits
• ? dispersal models should include multiple
  dispersal vectors
• Relative importance of long distance dispersal
  increases along light gradient
• ? communities probably differ in sensitivity for
  habitat fragmentation and in potential for
  ecological restoration