Plant Macrofossils

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Plant Macrofossils Bryophytes in Paleoclimate

• Calibration and Application of Paleo-Proxies
  Seminar

February 27, 2008
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Principles1. Dominant control on plants is
climate (temp., precip)2. Calibrations with
elevation, latitude3. Consistency among
sites4. Local data,regional signals, global
events5. Multiproxies in lake or wetland cores
(LOI, isotopes, chironomids, rhizopods)
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Methods

• Soak in NaOH
• Screen with 150 and 500 micron screens, washing
  with Hx0
• Pick under microscope

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Plant Macrofossils

• Strengths
• Species specificity
• Establish presence at site
• Complementary to pollen
• AMS C-14 dating material
• Limitations
• Absence not meaningful
• Few numbers

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Betula glandulosa cone bract
Dryas integrifolia leaf
TUNDRA MACROFOSSILS FROM SOUTHERN NEW ENGLAND AND
THEIR CURRENT DISTRIBUTION MAPS.
Salix bud
Vaccinium uliginosum leaf
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Birks, 1993
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Blomoy, western Norway2-6o C lower
Birks, l993
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Dryas fossil leaf
Subarctic Tundra
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(No Transcript)
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Aquatics
Najas seed
Potamogeton seed
Rubus seed
Caryophyllaceae seed
Upland plants
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Boreal Trees Shrubs
Picea glauca fossil needle
Picea fossil seed
Alnus fossil seed
Abies fossil needle tip
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Bryophytes (pH, water table)
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Janssens, 1983
More acidic
Wetter, rich fen
Emergent carpet
Rich fen pool