Landscape preservation under post‐European settlement alluvium in the south‐eastern Australian tablelands, inferred from portable OSL reader data

• Published in: Reproduction in Domestic Animals
• Main Authors: Portenga, Eric W., Bishop, Paul, Gore, Damian B, Westaway, Kira E
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: Oxford University Press 2016
• Subjects: preserved landscapes; PSA; Australia; portable OSL reader; optically stimulated luminescence; Geology and Earth Sciences; Science; Arctic
• Online Access: https://hdl.handle.net/2027.42/134129; https://doi.org/10.1002/esp.3942

Human land‐use changes leading to widespread erosion and gully incision have been well studied, but the effects that erosion and sediment mixing, which accompany the deposition of post‐(European) settlement alluvium (PSA), have in valley bottoms and wetlands receive considerably less attention. PSA overlying pre‐disturbance swampy meadow (SM) wetland sediments is commonly exposed along incised stream channel gully walls throughout the south‐eastern Australian Tablelands, providing an ideal setting in which to assess and understand better how PSA deposition affects valley bottoms and the wetland environments that often occupy them. Portable optically stimulated luminescence (pOSL) reader data were measured on bulk sediment samples from SM‐PSA stratigraphies at 16 locations throughout the south‐eastern Australian Tablelands to assess the effects of erosion and sediment mixing at the SM‐PSA boundary. Trends of pOSL data with depth at each profile were used in conjunction with visual profile descriptions to identify the stratigraphic boundary between SM and PSA sediment and to infer the degree of valley bottom erosion and sediment mixing during PSA deposition. At most sites, SM sediments experienced minimal, if any, disturbance during PSA deposition, and we refer to these as non‐eroded sites. Many sites, however, experienced a significant degree of erosion and sediment mixing – eroded sites – often corresponding to visually diffuse sedimentary boundaries between the two stratigraphic units. Our findings demonstrate that SM landscapes in the Tablelands can be preserved with minimal disturbance under PSA at non‐eroded sites and are preserved beneath a mixing zone at all eroded sites. Copyright © 2016 John Wiley & Sons, Ltd. Peer Reviewed http://deepblue.lib.umich.edu/bitstream/2027.42/134129/1/esp3942.pdf http://deepblue.lib.umich.edu/bitstream/2027.42/134129/2/esp3942_am.pdf