pollen zone

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pollen zone(pollen assemblage zone) The pollen and spore assemblage that is considered classically characteristic of a particular type of climate over a fairly extensive region and therefore indicative of it. Changes from one group of pollens to another characteristic assemblage are used to define pollen-zone boundaries. The standard British and very similar European late Devensian and Flandrian chronology recognizes eight major pollen zones. Zones I–III characterize the late-glacial sequence (i.e. Older Dryas (I), Allerød (II), and Younger Dryas (III)). More recently, based on North American work, the importance of regional variation in the typical zone floras has been acknowledged and a more flexible approach applied to the definition of pollen zones. Pollen zones are defined in terms of their pollen and spore profiles for a particular site, initially without reference to or matching with the standard zone models, which have strong climatic links. This allows local variations, often induced by human activities rather than climatic change, to be elucidated more clearly.

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