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| {{merge from|Palynofacies|discuss=Talk:Palynology#Proposed merge with Palynofacies|date=January 2014}}
| | My name is Jimmie Bucklin. I life in Voorschoten (Netherlands).<br><br>My site [http://mototai.ru/content/dog-training-kinds-containment-fence dog training pads wholesale] |
| [[Image:Palynologie-exemple.jpg|thumbnail|right|270px|[[Pine]] [[pollen]] under the microscope]]
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| [[Image:Trilete spores.png|thumb|A late Silurian sporangium bearing trilete spores. Such spores are the earliest evidence of life on land.<ref name=Gray1985>{{cite journal
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| | author = Gray, J.
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| | year = 1985
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| | title = The Microfossil Record of Early Land Plants: Advances in Understanding of Early Terrestrialization, 1970–1984
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| | journal = [[Philosophical Transactions of the Royal Society B]]
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| | volume = 309
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| | issue = 1138
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| | pages = 167–195
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| | doi = 10.1098/rstb.1985.0077
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| | last2 = Chaloner
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| | first2 = W. G.
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| | last3 = Westoll
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| | first3 = T. S.
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| | jstor=2396358
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| | bibcode=1985RSPTB.309..167G
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| }}</ref> '''Green''': A spore tetrad. '''Blue''': A spore bearing a trilete mark – the <math>Y</math>-shaped scar. The spores are about 30–35 μm across.]]
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| '''Palynology''' is the "study of dust" (from [[Greek language|Greek]] παλύνω - ''palunō'', "strew, sprinkle"<ref>[http://www.perseus.tufts.edu/hopper/text?doc=Perseus%3Atext%3A1999.04.0057%3Aentry%3Dpalu%2Fnw παλύνω],
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| Henry George Liddell, Robert Scott, ''A Greek-English Lexicon'', on Perseus</ref> and [[-logy]]) or "particles that are strewn". A classic palynologist analyses particulate samples collected from the air, water, or from deposits including sediments of any age. The condition and identification of those particles, organic and inorganic, give the palynologist clues to the life, the environment, and energetic conditions that produced them.
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| The term is sometimes narrowly used to refer to a subset of the discipline, which is defined as "the study of microscopic objects of macromolecular organic composition (i.e. compounds of carbon, hydrogen, nitrogen and oxygen), not capable of dissolution in hydrochloric or hydrofluoric acids."<ref>W.A.S. Sarjeant, 2002. 'As chimney-sweeps, come to dust': a history of palynology to 1970. pp. 273-327 In: Oldroyd, D. R. The earth inside and out: some major contributions to geology in the twentieth century. Geological Society (London) Special Publication no. 192.</ref> It is the science that studies contemporary and fossil [[palynomorph]]s, including [[pollen]], [[spores]], [[orbicule]]s, [[dinocysts]], [[acritarchs]], [[chitinozoa]]ns and [[Scolecodonts|scolecodont]]s, together with particulate organic matter (POM) and [[kerogen]] found in [[sedimentary]] rocks and [[sediment]]s. Palynology does not include [[diatoms]], [[foraminiferans]] or other organisms with [[siliceous]] or [[calcareous]] [[exoskeletons]].
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| Palynology is an interdisciplinary science and is a branch of [[earth science]] ([[geology]] or geological science) and [[biological science]] ([[biology]]), particularly [[plant science]] ([[botany]]). [[stratigraphy|Stratigraphical]] palynology is a branch of [[micropaleontology|micropalaeontology]] and [[paleobotany]], which studies [[fossil]] palynomorphs from the [[Precambrian]] to the [[Holocene]].
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| ==A history of palynology==
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| ===Early history===
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| The earliest reported observations of pollen under a microscope are likely to have been in the 1640s by the English [[botanist]] [[Nehemiah Grew]]<ref>
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| {{cite book
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| | last=Bradbury
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| | first=S
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| | year=1967
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| | title=The Evolution of the Microscope
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| | publisher=Pergamon Press
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| | place=New York
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| | pages=375 p}}</ref> who described pollen, the stamen, and correctly predicted that pollen is required for sexual reproduction in flowering plants. As microscopes began to improve, further studies included work by [[Robert Kidston]] and [[P. Reinsch]] who examined the presence of spores in coal and compared them to modern spores.<ref>
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| {{cite journal
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| | last= Jansonius
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| | first=J
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| | coauthors=D.C. McGregor
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| | year=1996
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| | title=Introduction, Palynology: Principles and Applications
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| | journal=AASP Foundation
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| | volume=1
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| | pages=1–10
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| | url=http://www.palynology.org/history/jansonmcgrgrhist.html}}</ref> The early pioneers also included [[Christian Gottfried Ehrenberg]] ([[radiolarian]]s, [[diatoms]] and [[dinoflagellate cysts]]), [[Gideon Mantell]] ([[desmid]]s) and [[Henry Hopley White]] ([[dinoflagellate cysts]]).
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| ===Modern palynology===
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| The earliest quantitative analysis of pollen was published by [[Lennart von Post]] who laid out the foundations of modern pollen analysis in his [[Kristiania]] lecture of 1916.<ref name="FIPol">
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| {{cite book
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| | last=Fægri | first= Knut |authorlink=Knut Fægri
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| | coauthors= [[Johs. Iversen]]
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| | url=http://www.palynology.org/history/erdtman.html
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| | title=Textbook of Pollen Analysis
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| | publisher=[[Blackwell Scientific Publications]]
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| | year=1964
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| | place=Oxford}}</ref> Pollen analysis was initially confined to Nordic countries because many early publications were in Nordic languages.<ref name="InMem">
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| {{cite journal
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| | last=Faegri
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| | first= Knut
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| | title=In memoriam O. Gunnar E. Erdtman
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| | journal=Pollen et Spores
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| | year=1973
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| | volume=15
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| | pages=5–12
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| }}</ref> This isolation ended with the publication of [[Gunnar Erdtman]]'s thesis of 1921 when pollen analysis became widespread throughout [[Europe]] and [[North America]] for use in studies of [[Quaternary]] vegetation and climate change.<ref name="FIPol" />
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| Modern pollen analysis dates back to [[Lennart von Post]] when he presented a paper on fossil pollen grains in [[Sweden|Swedish]] bogs to the 1916 [[Scandinavian Scientist Conference]] in [[Oslo]].<ref>von Post, L (1918) "Skogsträdpollen i sydsvenska torvmosslagerföljder", Forhandlinger ved de Skandinaviske naturforskeres 16. møte i Kristiania 1916: p. 433</ref> The paper was repeated in the same year in [[Stockholm]] but was not fully published until 1918. Antecedents of this work can be traced to the writings of scientists such as Früh (1885),<ref>Früh, J (1885) "Kritische Beiträge zur Kenntnis des Torfes", Jahrb.k.k.Geol.Reichsanstalt 35</ref> who enumerated most of the common tree pollen types, together with a considerable number of [[spore]]s and [[herb]] pollen grains. In a study of bottom samples from Swedish lakes by Trybom (1888),<ref>Trybom, F (1888) "Bottenprof fran svenska insjöar", Geol.Foren.Forhandl.10</ref> [[Pinus]] (Pine) and [[Picea]] (Spruce) pollen was found in such profusion that he considered them to be serviceable as "[[index fossils]]". [[Georg F.L. Sarauw]] studied fossil pollen of middle Pleistocene age ([[Cromerian]]) from the harbour of [[Copenhagen]].<ref>{{cite journal | last=Sarauw | first=G. F. L. | year= 1897 | title = Cromer-skovlaget i Frihavnen og trælevningerne i de ravførende sandlag ved København | language = Danish | trans_title = The Cromer Forest layer in the Free Harbour and Wood Remains in the Amber containing strata near Copenhagen | journal = Meddelelser fra Dansk Geologisk Forening / Bulletin of the Geological Society of Denmark | volume=1 | issue=4 | pages= 17–44 | url = http://2dgf.dk/xpdf/bull-1897-1-4-17-44.pdf }}</ref> Lagerheim (in Witte 1905) and C.A.Weber (in H.A.Weber 1918) appear to be among the first to undertake 'percentage frequency' calculations.
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| Pollen analysis was refined and developed by [[Johannes Iversen]] and [[Knut Fægri]] in their now classical textbook on the subject.<ref>Fægri, K. & Iversen, J. (1989) ''Textbook of pollen analysis''. 4th ed. John Wiley & Sons, Chichester. 328 p.</ref>
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| The term ''palynology'' was introduced by Hyde and Williams in 1944, following correspondence with the Swedish [[geologist]] Antevs, in the pages of the [[Pollen Analysis Circular]] (one of the first journals devoted to pollen analysis, produced by [[Paul Sears]] in North America). Hyde and Williams chose ''palynology'' on the basis of the [[Ancient Greek|Greek]] words ''paluno'' meaning 'to sprinkle' and ''pale'' meaning 'dust' (and thus similar to the [[Latin]] word ''pollen'').<ref>
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| {{cite journal
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| | last=Hyde
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| | first=H.A.
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| | coauthors=D.A. Williams
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| | url=http://www.geo.arizona.edu/palynology/riteword.html
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| | title=The Right Word
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| | journal=Pollen Analysis Circular
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| | volume=8
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| | pages = 6
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| | year=1944
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| }}</ref>
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| == Methods of study ==
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| ===Palynomorphs===
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| Palynomorphs are broadly defined as organic-walled [[microfossil]]s between 5 and 500 [[micrometre]]s in size. They are extracted from rocks and [[pollen core|sediment cores]] both physically, by [[sieve analysis|wet sieving]], often after ultrasonic treatment, and chemically, by using chemical digestion to remove the non-organic fraction.
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| A palynomorph (from [[Ancient Greek|Greek]], meaning "strewn or sprinkled forms") is a particle of a size between five and 500 micrometres, found in rock deposits ([[sedimentary rock]]s) and composed of organic material such as [[chitin]], [[pseudochitin]] and [[sporopollenin]]. Described palynomorphs are sometimes referred to as palynotaxa.
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| Palynomorphs form a [[geological]] record of importance in determining the type of [[prehistoric life]] that existed at the time the sedimentary formation was laid down. As a result, these microfossils give important clues to the prevailing [[paleogeography|climatic conditions]] of the time. Their paleontological utility derives from an abundance numbering in millions of [[Cell (biology)|cells]] per gram in organic marine deposits, even when such deposits are generally not [[fossiliferous]]. Palynomorphs, however, generally have been destroyed in [[Metamorphic rock|metamorphic]] or recrystallized rocks.
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| Typically, palynomorphs are [[dinoflagellate cysts]], [[acritarch]]s, [[spore]]s, [[pollen]], [[fungi]], [[scolecodonts]] (scleroprotein teeth, jaws and associated features of [[polychaeta|polychaete]] [[annelid]] worms), [[arthropod]] organs (such as [[insect]]-mouth parts), [[chitinozoa]]ns and [[foram|microforam]]s.
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| Palynomorph microscopic structures that are abundant in most sediments are resistant to routine pollen extraction including strong acids and bases, and acetolysis, or density separation.<!--Check this sentence, before I copy/edit-ted it. It had GROSS errors.-->
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| ===Chemical preparation===
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| Chemical digestion follows a number of steps.<ref>{{cite book
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| |last=Bennett
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| |first=K.D.
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| |coauthors=Willis, K.J.
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| |chapter=Pollen
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| |year=2001
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| |title=Tracking Environmental Change Using Lake Sediments. Volume 3: Terrestrial, algal, and siliceous indicators
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| |editor-last=Smol
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| |editor-first=John P.
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| |editor2-last=Birks
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| |editor2-first=H. John B.
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| |editor3-last=Last
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| |editor3-first=William M.
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| |publisher=Kluwer Academic Publishers
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| |place=Dordrecht
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| |pages=5–32}}
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| </ref> Initially the only chemical treatment used by researchers was treatment with [[Potassium hydroxide|KOH]] to remove [[Humic acid|humic]] substances; defloculation was accomplished through surface treatment or ultra-sonic treatment, although sonification may cause the pollen exine to rupture.<ref name="InMem" /> The use of [[hydrofluoric acid]] (HF) to digest [[silicate]] [[mineral]]s was introduced by Assarson and Granlund in 1924, greatly reducing the amount of time required to scan slides for palynomorphs.<ref>{{cite journal
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| | last=Assarson
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| | first=G. och E.
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| | coauthors=Granlund, E.
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| | title=En metod for pollenanalys av minerogena jordarter
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| | journal=Geol. Foren. Stockh. Forh.
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| | volume=46
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| | pages=76–82
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| | doi=10.1080/11035892409444879
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| | year=1924}}
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| </ref> Palynological studies using peats presented a particular challenge because of the presence of well preserved organic material including fine rootlets, moss leaflets and organic litter. This was the last major challenge in the chemical preparation of materials for palynological study. [[Acetolysis]] was developed by Gunnar Erdtman and his brother to remove these fine cellulose materials by dissolving them.<ref>{{cite journal
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| | last=Erdtman
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| | first= O.G.E.
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| | title=Uber die Verwendung von Essigsaureanhydrid bei Pollenuntersuchungen
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| | journal= Sven. Bot. Tidskr.
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| | volume=28
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| | pages=354–358}}</ref> In acetolysis the specimen is treated with [[acetic anhydride]] and [[sulfuric acid]], dissolving [[cellulose|cellulistic]] materials and thus providing better visibility for palynomorphs.
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| Some steps of the chemical treatments require special care for safety reasons, in particular the use of HF which diffuses very fast through the skin and, causes severe chemical burns, and can be fatal.<ref>{{cite web
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| |url=http://www.monash.edu.au/ohs/topics/hazard-alerts/hydrofluoric-acid-fatality.html
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| |title=Hydrofluoric acid fatality in Perth - hazard alert
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| |date=1995-03-06
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| |accessdate=2011-12-18}}
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| </ref>
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| Another treatment includes kerosene flotation for [[chitin]]ous materials.
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| ===Analysis===
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| Once samples have been prepared chemically, they are mounted on [[microscope]] slides using silicon oil, glycerol or glycerol-jelly and examined using light [[microscopy]] or mounted on a stub for [[Scanning electron microscope|scanning electron microscopy]].
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| Researchers will often study either modern samples from a number of unique sites within a given area, or samples from a single site with a record through time, such as samples obtained from [[peat]] or lake sediments. More recent studies have used the modern analog technique in which paleo-samples are compared to modern samples for which the parent vegetation is known<ref>{{cite journal
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| |last=Overpeck
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| |first=J.T.
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| |coauthors=T. Webb, I.C. Prentice
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| |year=1985
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| |title=Quantitative interpretation of fossil pollen spectra: Dissimilarity coefficients and the method of modern analogs
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| |journal=Quaternary Research
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| |volume=23
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| |pages=87–108
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| |doi=10.1016/0033-5894(85)90074-2|bibcode = 1985QuRes..23...87O }}</ref>
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| When the slides are observed under a microscope, the researcher counts the number of grains of each pollen taxon. This record is next used to produce a [[pollen diagram]]. These data can be used to detect [[human impact on the environment|anthropogenic]] effects, such as logging,<ref>
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| {{cite journal
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| |last=Niklasson
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| |first=Mats
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| |coauthors=Matts Lindbladh, Leif Björkman
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| |title=A long-term record of ''Quercus'' decline, logging and fires in a southern Swedish ''Fagus-Picea'' forest
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| |journal=Journal of Vegetation Science
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| |year=2002
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| |volume=13
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| |pages=765–774
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| |url=http://www.bioone.org/perlserv/?request=get-abstract&doi=10.1658%2F1100-9233(2002)013%5B0765%3AALROQD%5D2.0.CO%3B2
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| |doi=10.1658/1100-9233(2002)013[0765:ALROQD]2.0.CO;2
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| |issue=6
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| }}</ref> traditional patterns of land use<ref>
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| {{cite journal
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| |last=Hebda
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| |first=R.J.
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| |coauthors= R.W. Mathewes
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| |title=Holocene history of cedar and native cultures on the North American Pacific Coast
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| |journal=Science
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| |volume=225
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| |pages=711–713
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| |year=1984
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| |doi=10.1126/science.225.4663.711
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| |pmid=17810290
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| |issue=4663|bibcode = 1984Sci...225..711H }}</ref> or long term changes in regional climate<ref>{{cite journal
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| |last=Heusser
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| |first= Calvin J.
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| |coauthors=L.E. Heusser, D.M. Peteet
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| |title=Late-Quaternary climatic change on the American North Pacific coast
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| |journal=Nature
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| |volume=315
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| |pages=485–487
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| |year=1985
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| |doi=10.1038/315485a0
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| |issue=6019|bibcode = 1985Natur.315..485H }}</ref>
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| Palynology can be applied to problems in many fields including [[geology]], [[botany]], [[paleontology]], [[archaeology]], [[pedology (soil study)]], and [[physical geography]].
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| == Applications ==
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| Palynology is used for a diverse range of applications, related to many scientific disciplines:
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| * [[Biostratigraphy]] and [[geochronology]]. Geologists use palynological studies in biostratigraphy to correlate [[stratum|strata]] and determine the relative age of a given bed, horizon, formation or [[stratigraphy|stratigraphical]] sequence.
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| * [[paleoecology|Palaeoecology]] and [[climate change]]. Palynology can be used to reconstruct past [[vegetation]] (land plants) and [[ocean|marine]] and [[freshwater]] [[phytoplankton]] communities, and so infer past [[natural environment|environmental]] ([[paleoenvironment|palaeoenvironment]]al) and [[paleoclimatology|palaeoclimatic]] conditions.
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| * [[organic compound|Organic]] [[palynofacies]] studies, which examine the preservation of the particulate organic matter and [[palynomorph]]s provides information on the depositional environment of sediments and depositional palaeoenvironments of [[sedimentary|sedimentary rocks]].
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| * [[Geothermal]] alteration studies examine the [[color|colour]] of [[palynomorph]]s extracted from rocks to give the thermal alteration and [[hydrocarbon|maturation]] of [[sedimentary]] sequences, which provides estimates of maximum [[paleotemperatures|palaeotemperatures]].
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| * [[Limnology]] studies. Freshwater [[palynomorphs]] and animal and plant fragments, including the [[prasinophyte]]s and [[desmid]]s ([[green alga]]e) can be used to study past lake levels and long term [[climate change]].
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| * [[scientific classification|Taxonomy]] and [[evolution|evolutionary studies]].
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| * [[Forensic palynology]]: the study of [[pollen]] and other [[palynomorph]]s for evidence at a crime scene.
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| * [[Allergy]] studies. Studies of the geographic distribution and seasonal production of pollen, can help sufferers of allergies such as [[hay fever]].
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| * [[Melissopalynology]]: the study of pollen and spores found in honey.
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| * [[Archaeological]] palynology examines human uses of plants in the past. This can help determine seasonality of site occupation, presence or absence of agricultural practices or products, and 'plant-related activity areas' within an archaeological context. [[Bonfire Shelter]] is one such example of this application.
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| Because the distribution of [[acritarchs]], [[chitinozoa]]ns, [[dinoflagellate cysts]], [[pollen]] and [[spore]]s provides evidence of [[stratigraphy|stratigraphical correlation]] through [[biostratigraphy]] and [[palaeoenvironment]]al reconstruction, one common and lucrative application of palynology is in [[petroleum|oil]] and [[Natural gas|gas]] exploration.
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| Palynology also allows scientists to infer the climatic conditions from the vegetation present in an area [[geologic timescale|thousands or millions of years]] ago. This is a fundamental part of research into [[climate change]].
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| ==See also==
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| * [[Aperture (botany)]]
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| == References ==
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| {{Reflist}}
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| *Moore, P.D., et al. (1991), ''Pollen Analysis'' (Second Edition). Blackwell Scientific Publications. ISBN 0-632-02176-4
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| *Traverse, A. (1988), ''Paleopalynology''. Unwin Hyman ISBN 0-04-561001-0
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| *Roberts, N. (1998), ''The Holocene an environmental history'', Blackwell Publishing. ISBN 0-631-18638-7
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| == External links ==
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| * [http://www.geo.arizona.edu/palynology/ifps.html International Federation of Palynological Societies]
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| *[http://www.ifpindia.org/Palaeoenvironments-in-South-India.html Palynology Laboratory, French Institute of Pondicherry, India]
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| * [http://www.rbgkew.org.uk/scihort/palyn.html The Palynology Unit, Kew Gardens, UK]
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| * [http://www.paldat.org/ PalDat, palynological database hosted by the University of Vienna, Austria]
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| * [http://www.nhm.ac.uk/hosted_sites/tms/ The Micropalaeontological Society]
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| * [http://www.palynology.org/ The American Association of Stratigraphic Palynologists (AASP)]
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| * [http://www.shef.ac.uk/~cidmdp/ Commission Internationale de Microflore du Paléozoique (CIMP)], international commission for Palaeozoic palynology.
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| * [http://www.linnean.org Linnean Society Palynology Specialist Group (LSPSG)]
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| * [http://www.scirpus.ca/cap/cap.shtml Canadian Association of Palynologists]
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| * [http://www.geo.arizona.edu/palynology/polident.html Pollen and Spore Identification Literature]
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| * [http://www.palynologischekring.nl Palynologische Kring, The Netherlands and Belgium]
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| [[Category:Palynology| *]]
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| [[Category:Earth sciences]]
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| [[Category:Archaeological science]]
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| [[Category:Subfields of paleontology]]
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| [[Category:Fossils]]
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| [[Category:Branches of botany]]
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