Taphonomy of Prospective Plant Macrofossils in a River Catchment on Spitsbergen

Abstract

SUMMARYRepresentation of recent plant parts in fluvial sediments and in the vegetation of a braided-river catchment on Spitsbergen was studied quantitatively in order to provide a model for taphonomy of plant macrofossils during cold stages of the British Pleistocene. The area studied on the Adventelva is in a region with continuous permafrost and on a river that has high (nival) peak discharges in early summer, features that were also present in the British lowlands during the Pleistocene cold stages.Deposition of 'prospective macrofossils' in silts of channels on the Adventelva floodplain occurred mainly during the decline from the early summer peak of discharge. Surface runoff overland was much the most important process by wKich 'prospective macrofossils' reached river channels, and this accounts for them giving a surprisingly even overall representation of the abundance of similar parts in the vegetation. Taxa having 'prospective macrofossil parts' that were under-represented in the deposits had parts that were: (a) very small, (b) of soft or perishable texture, (c) firmly attached to stems, (d) neither deciduous nor renewed annually, or (e) they were plants growing on the river floodplain. Taxa with parts over-represented in the deposits were: (a) those with parts that break into numerous identifiable fragments, or (b) they were plants growing in localized areas of late snow-lie.

An objective method based on assemblages of subfossil plant macro-remains to reconstruct past natural vegetation: a case study at Swifterbant, The Netherlands

“…A quantitative translation of our seed numbers into standing vegetation would require extensive studies on the relationship between species composition in an area and the accumulation of the remains in drift litters (Moore 1986, p. 545). Such studies have been performed by Holyoak (1984) and Wolters and Bakker (2002). However, to make such a study applicable to our dataset, it would have to be carried out in an area comparable to the area under study, which would inevitably require some circular reasoning.…”

Developmental morphology of ovules and seeds of Nymphaeales

“…The significance of comparative neo-and paleobotanical studies is increasingly obvious, because approaches combining fossil data with molecular data improve phylogenetic interpretations. Fossil records of delicate ovules are scarce as compared to seed fossils due to taphonomical bias (Holyoak, 1984). Therefore, combined data of seed fossils and extant angiosperm ovules are useful for determining the primitive characteristics of ovules.…”

Plant macroscopic remains from recent sediments of Banks Island, Northwest Territories, and Bathurst Island, Nunavut, Canada, and the interpretation of Quaternary cold stage plant macroscopic assemblages

“…Although fluviatile transport brings the plant remains to the sediment, the origin from parent plants may be diverse, with overland movement by surface run-off (Holyoak, 1982) or by spring or winter dispersal by wind (Glaser, 1981). Such processes will also affect the final selection of remains for deposition in sediment, making the pathway from plant to sediment a complex one.…”

“…Birks, 1973;West et al, 1974;Ritchie et al, 1987), but there have been far fewer in respect of plant macrofossils (e.g. Glaser, 1981;Holyoak, 1982), in spite of their significance for reconstructing past vegetation and climate.…”