Fire-prone plant communities and palaeoclimate of a Late Cretaceous fluvial to estuarine environment, Pecinov quarry, Czech Republic

The botanical identity and facies distribution of fossil charcoal is descri bed from Middle to Late Cenomanian (90-94 Ma) fluvial to estuarine units at Pecinov quarry, near Prague, Czech Republic. Braided alluvial facies assoc iations contain charred conifer woods (family Pinaceae) possibly derived fr om upland forest fires, and abundant charred angiosperm woods, flowers and inflorescences (families Lauraceae and ?Platanaceae) derived from riparian gallery forest fires (Unit 2). Retrogradational coastal salt marsh facies a ssociations contain abundant charred conifer wood (families Cheirolepidiace ae and Cupressaceae/Taxodiaceae) derived from fires in halophytic backswamp forest, and rare pinaceous charred cones and lauraceous angiosperm wood wa shed downstream from fires further inland (Units 3-4). Progradational coast al facies associations within an estuary mouth setting contain abundant cha rred conifer wood (family Cup ressaceae/Taxodiaceae), common taxodiaceous c onifer and angiosperm leaves, fern rachises, and lycopsid stems derived fro m fires in mesic backswamp taxodiaceous forests and supra-tidal fern-lycops id thickets (Unit 5). Growth rings in angiosperm and conifer woods, leaf ph ysiognomy and computer models indicate that climate was equable, warm and h umid, but that there was a short annual dry season; most fires probably occ urred during these annual drought periods. The abundance of charcoal and th e diversity of taxa preserved in this state indicate that nearly all plant communities were fire-prone. Physiognomically, the Pecinov flora resembles present-day seasonally-dry subtropical forests where fires are a common occ urrence.