n -Alkane Distribution—A Paleovegetation Change Indicator during the Period from Late Glacial to Late Holocene on Russian Plain (Bryansk Region)

摘要

Loess-paleosol series are well preserved in the south part of the Russian Plain. However, these sequences have a low number of studies on their organic matter, such as researches of isotope composition, n -alkane and other biomarkers. Thus, the purpose of the study was to reconstruct vegetation conditions from the Late Glacial to Late Holocene. We used the leaf wax-derived n -alkanes to detect vegetation evolution of the Bryansk Region. The stable carbon isotope composition of organic matter and pedogenic carbonates was carried out for the same aim. Three paleosols (of Lasko, B?lling-Aller?d warmings and Holocene second humus horizons) and modern soils of different relief positions were investigated. n -Alkane distribution, as well as isotope composition indicates changes from grassy to woody vegetation during this period. The use of biomarkers such as n -alkanes helps to more clearly interpret isotopic data.