A neotaphonomic experiment in pollen oxidation and its implications for archaeopalynology

Mid Holocene vegetation reconstruction from Vanevan peat (south-eastern shore of Lake Sevan, Armenia)

“…High amounts of Cichorioideae can be considered as taphonomically biased as this pollen grain is less easily corroded than other grains (e.g. Bottema, 1975;Hall, 1981;Havinga, 1984;Lebreton et al, 2010). According to Havinga (1984), dominance of Cichorioideae is associated with low taxa diversity and inconsistencies in the pollen assemblage.…”

The impact of oxidation on spore and pollen chemistry

“…The physical effects of oxidative treatments on sporomorphs are well known: initial darkening of the exine, increased size, degradation and, in time, destruction (Johnson 1985;Traverse, 1988;Wood et al, 1996;Lebreton et al, 2010). However, there is currently much less of an understanding of how oxidation affects sporomorph chemistry, and what this means for recovering information on UV-B flux and plant taxonomy from standard palynological preparations, and from fossil sporomorphs that have undergone natural oxidation prior to burial.…”

Galilee Blooming: First palynological and archaeological data from an Early Byzantine Cistern at Horvat Kur

“…Those processes including the vertical transport of palynomorphs through sediments via water (downwash) or by animal activity (bioturbation) are comparable to processes observed in terrestrial soils (Dimbleby 1961;Davidson et al 1999;Gavin and Brubaker 1999). Consequently, the pollen concentration in archaeological contexts, especially in dry soils in arid regions, is often too low to achieve a precise portrait of the vegetation, the record is usually greatly influenced by anthropogenic disturbances and alteration of palynomorphs has often led to overrepresentation of more resistant pollen types (Fish 1989, see references in Lebreton et al 2010). Poor, respectively differential pollen preservation may lead to the accumulation of certain pollen types, e.g., Cichorioideae, especially under dry climatic conditions (Weinstein-Evron and Chaim 1989;Weinstein-Evron 1994;compare Bottema 1975).…”

“…Taphonomical studies on different pollen and sporetypes have shown that Cichorioideae pollen were more resistant to decay than other pollen-types (Havinga 1984). Consequently, this pollen-type is supposedly over-represented, e.g., in pollen spectra from archaeological sites (Bottema 1975), although more recent studies on the oxidation of different pollen types underline that oxidation might not be the only taphonomical process involved since Cichorioideae pollen do not appear to be more resistant than other experimentally tested pollen types (Lebreton et al 2010). Lebreton et al (2010) point out that, due to their unique morphology, pollen of Cichorioideae is simply less easy to confuse with other pollen types even after alteration.…”

“…Consequently, this pollen-type is supposedly over-represented, e.g., in pollen spectra from archaeological sites (Bottema 1975), although more recent studies on the oxidation of different pollen types underline that oxidation might not be the only taphonomical process involved since Cichorioideae pollen do not appear to be more resistant than other experimentally tested pollen types (Lebreton et al 2010). Lebreton et al (2010) point out that, due to their unique morphology, pollen of Cichorioideae is simply less easy to confuse with other pollen types even after alteration. On the other hand, Cichorioideae and Tubuliflorae are also rather resistant and similarly typical open land indicators (Neumann et al 2007a, b).…”