Pollen, phytoliths and palynomorphs

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Pollen, phytoliths and palynomorphs

Importance of waterborne pollen


Distance classification of pollen

• Local,

• Extralocal,

• Regional,

• Long distance


What happens during transport


• DEGRADED

• CORRODED

• CRUMPLED

• BROKEN

• HIDDEN


Pollen in air


Pollen in water


Pollen in coastal deposits

• Biological controls on

deposition


Pollen in lakes


Pollen in bogs

• Generally great preservation

• Very different catchment than lakes


Lakes vs. bogs


Other places for pollen

• Packrat middens

• Paleosols

• Spring deposits

• Caves

• Fecal deposits


Preservation requirements

http://www.geo.arizona.edu/palynology/geos581/lec_07.html


• Coring

Sampling


Sampling 2

• Number of samples,

volume

• The darker, the better


Pollen extraction

• Must analyze comparable volumes of sediment

• Subsampling strategy

• General procedure

– Screen big stuff out

– (Add tracer)

– (centrifuge)

– Dissolve everything else

– Put grains on slide

– Count and ID (!)



The pollen diagram


Pollen

divided into

zones


Some things to keep in mind…

• Sedimentological changes masking as climatic

• The effect of unidentifiable grains

– Greater as you go older

• Was modern work done

• Dating and sedimentation rates!!

• Catchment size and scale

• Strength of the analog

– CO 2


Does it actually work

• Yes!

• Sort of.

• Sure, it

does.

• Mostly.


PreQuaternary pollen

• Generally restricted to higher

taxonomic levels (family),

qualitative climate indications

• NLR (nearest living relative)

analogy


• Mesozoic and older Cenozoic palynofloras use

biogeographic methods.


Best case scenario

• Mesozoic genus Classopollis

• Found with cones and leaves from plants in

the family Cheirolepidiaceae.

– Associated with rocks, other plants

– warm and semiarid andor seasonal climates


Pollen records

• …document floristic turnover at TRJ boundary

(Newark Supergroup)

• “ at K/T boundary (Western US)

• “Among the various hypotheses to explain the

extinction that closed the Mesozoic era were

allergies by dinosaurs to pollen produced by

flowering plants, increased radiation levels that led

to male dinosaur sterility, diseases brought by

migrating animals, and a gradual climate

deterioration that the dinosaurs were unable to cope

with.”

http://www.emc.maricopa.edu/faculty/farabee/biobk/BioBookPaleo5.html


Phytoliths

• Good in tropical rainforests where

pollen poorly preserved

• Also survives oxidation nicely

• Generally don’t move around much

• Widely used in studies of early

agriculture

– Degraded cattle and sheep dung, and

peat can be identified

– Also sampled from teeth, cooking

residues, and edges of stone tools

• Hard to separate from silt fraction

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