Lipid biomarkers of manuring practice in relict anthropogenic soils

This investigation tests the extent to which free soil lipids reflect known manuring practices associated with a relict twelth- to nineteenth-century anthropogenic deep top soil in West Mainland Orkney. The results demonstrat e that total lipid extracts reflect the expected spatial variability in man uring intensity across the deep top soil areal declining with distance from the farmstead. Specific organic manure inputs are also identified; the pre sence of campesterol, sitosterol and 5 beta-stigmastanol confirm expected c omposted turf and ruminant animal manure application to the deep top soil a rea. A departure from the expected results is the presence of coprostanol, reflecting omnivorous animal manure deposition and confirmed as pig manure through the identification of hyodeoxycholic acid. These analyses establish that lipid biomarkers of past land-management activity are retained in med ieval to early modern relict landscapes, and that they allow more precise i dentification of manure sources and patterns of deposition than conventiona l pedological techniques. Further, they suggest that historic documentation forms only a partial record of manuring practices.