Terrestrial Palaeoecology and Global Change

Chapter 3. Palaeoecology
61
Osmundion: a zonal mesotemperate peat-bog facies union of fern-marsh assemblages,
with Osmundo-Equisetetum (ferganensae) as an edaphic association of waterlogged
alluvial soil.
Czekanowskion: a major zonal mesotemperate (also interzonal, but rapidly decreasing
south of the mesotemperate realm) delta-plain/flood-plain peat-forming union of woody
wetland assemblages, with edaphic (waterlogged alluvial to peat-bog facies) Czekano-
Pseudotorellietum (angustifoliae) and Czekano-Pityophylletum associations.
Elatidion: an interzonal mesotemperate or warm-temperate delta-plain back-marsh
facies union of a taxodiaceous woodland type, polydominant, admixed by Czekanowskia
or boggy cycadophytes, spread over fern marshlands as Elati-Osmundetum (Elati-Todetum
in the warm-temperate zone).
Pityophyllion: an interzonal mesotemperate to warm-temperate peat-bog facies union
of a bog forest type represented by pure Pityophylletum angustifoliae (longifoliae) or
by a mixed Pityo-Pseudotorellietum or else in association with cycadophytes and bog
ferns, as Pityo-Nilssonietum, Pityo-Osmundetum, etc.
Class Ptilophylletea (Cycadeoidetea), includes the Meso-Mediterranean vegetation
of a warm-temperate to xerotemperate aspect, taxonomically rich, dominated by the
pachycaul cauliflorous bennettites of the pinnate Ptilophyllum, Zamites, Otozamites
leaf morphotypes and by brachyphyllous conifers and gnetalean coniferoids of the scaleleaved
Brachyphyllum, Pagiophyllum, Frenelopsis, Pseudofrenelopsis morphotypes,
with diverse matoniaceous, schizaeaceous and cyatheaceous ferns (Nathorstia, Klukia,
Tempskya, Cyathea), and with giant horsetails in the wetlands. The major unions are:
Ptilophyllion: a major zonal estuarine–lagoonal to riparian facies union of xeromorphic
bennettite assemblages, monodominant (Ptilophylletum) to polydominant with other
bennettites or a peltasperm Pachypteris as co-dominants in estuarine associations
(Ptilo-Otozamitetum, Ptilo-Pachipteridetum), with a fern-marsh component in the delta
fringe associations (Ptilo-Todetum) and with Zamites–Zamiophyllum large-leaved
bennettitalen morphotypes prominent in a riparian association Ptilo-Zamitetum.
Brachyphyllion: an interzonal but prevailingly xerothermic, fluvial to lacustrine facies
union of xeromorphic scale-leaved woodland to shrubland vegetation with diverse
bennettitalean, cycadophytic and coniferoid components. The associations are numerous,
not yet strictly defined, with Ptilophyllum, Otozamites, Ctenis, Baierella, Czekanowskia
as co-dominants.
The Late Cretaceous to Early Tertiary examples are given in Krassilov (1976a, 1979)
and below.
III.3. Basinal systems
The dead mass exported from a local ecosystem is imported and partly recycled by
neighbouring ecosystems downslope (as in the case of eutrophication by terrestrial or-