Pollen as a chronometer and sediment tracer, Burrinjuck Reservoir, Australia

Abstract

Pollen analysis is widely used to reconstruct vegetation and land use histories, but can also provide sedimentological information . At Burrinjuck Reservoir, in south-eastern Australia, annual grass pollen peaks are used to distinguish each year's sediment, even when there are no visible laminations . In conjunction with other dating methods, this allows the determination of year by year influxes of all sediment components . Pollen grains in the Burrinjuck sediments are shown to be predominantly waterborne so that they can be used to trace sediment to its source in particular vegetation stands . Pollen concentration and the proportion of damaged pollen might also distinguish sediment eroded from topsoils and that from subsoils . Pollen analysis can thus be used to locate specific erosion events in both time and space .

Monitoring fluvial pollen transport, its relationship to catchment vegetation and implications for palaeoenvironmental studies

“…The results of this catchment monitoring also have implications for the interpretation of near-shore marine cores which still present difficulties of interpretation (Clark, 1986;Wilmshurst et al, 1999;McGlone, 2001). Studies on modern pollen deposition in coastal waters indicate the rapid incorporation of pollen to marine sediments (Chmura and Eisma, 1995).…”

Seasonality of modern pollen and sediment deposition in an estuarine context: the Severn Estuary Levels, southwest England

“…The ebb and flow of the tides would be expected to resuspend some pollen, and potentially cause sorting according to pollen size and buoyancy (Brush and Brush, 1972;Holmes, 1990Holmes, , 1994. Several studies have suggested that pollen grains in suspension in water behave as fine silt-size particles (Brush and Brush, 1972;Clark, 1986;Farr, 1989;Holmes, 1994), although some contribute together with mineral matter to larger particles as the result of flocculation/agglomeration, to be expected in a saline environment, or are incorporated into faecal pellets (Pickrill, 1987;Chmura and Eisma, 1995;Chmura et al, 1999).…”

Seasonal patterns of pollen and the use of pollen as a chronometer in the north‐western Loess Plateau of China

“…Moreover, seasonal variations in pollen assemblages can even be used to distinguish seasonal layers in unlaminated sediments or those with indistinct laminations (Clark, 1986;Rull et al, 2017), such as reservoir sediments (Clark, 1986) and tidal flat sediments (Wang et al, 2000).…”

“…A number of previous studies have found that analysing the seasonal pollen signal can enable the distinction of annual layers in lake sediment (Gauthier & Muñoz, 2009;López-Merino et al, 2016;Lotter, 1989;St. Jacques et al, 2008;Tippett, 1964), even in the absence of macroscopically visible laminations (Clark, 1986;Rull et al, 2017). If this palynology could reach a seasonal resolution, the latter would provide the highest temporal resolution for lake sediments and represents a dating technique with an annual resolution that was comparable to those derived from tree rings, ice core laminations or speleothems.…”

“…Pollen analysis can be used not only to reconstruct the vegetation and the environment at different timescales but can also be used in new ways as a chronometer (Clark, 1986;Rull et al, 2017). The hypothesis is that if there had been marked seasonality during the flowering and pollen production stages of terrestrial plants and the prompt transport of pollen to the lake, each sediment layer should contain the pollen grains that had been dispersed at the time of year when the layer was deposited.…”