Simultaneous extraction of phytoliths, pollen and spores from sediments

Archaeological sediments often offer opportunities to examine local palaeoenvironmental conditions from analysis of included microfossils. On-site conditions commonly vary, and thus so do the preservation conditions for microfossils. Consequently, a range of palynological preparation techniques are commonly used. While different types of microfossils provide valuable palaeoenvironmental information, the use of separate extraction methods for different microfossil types may be both time- and resource-consuming, especially where the recovery predicability is low. This paper examines the possibility of combining preparation techniques for three commonly encountered microfossils—pollen, spores and phytoliths—by comparing pollen extractions using heavy liquid extraction and standard pollen recovery procedures. Although the use of heavy liquids for pollen and spore preparations has been well-documented, for several reasons it has not been a favoured technique for pollen extraction. The research reported here shows that for most of the sediments tested, heavy liquid extraction procedures produced comparable results to those arising from standard pollen extraction techniques. For oxidized sediments, especially, more reliable results are likely to be obtained from heavy liquid extraction procedures than from those employing acetolysis. Overall, heavy liquid procedures allow complementary suites of data to be investigated with the least cost and effort, thus enabling palynologists and phytolithologists to adopt more effective research practices for environmental reconstruction.