The potential of leaf wax biomarkers from fluvial soil-sediment sequences for paleovegetation reconstructions - Upper Alazani River, central southern Greater Caucasus (Georgia)

With respect to paleovegetation patterns, our investigations gave the following results: (i) Leaf waxes in fluvial sediments deposited prior to/around the Pleistocene/Holocene transition and between ca. 5 and 1.7 cal. ka BP are indicative of more deciduous trees/shrubs in the catchment compared with the other periods that were dominated by grasses/herbs. Considering a possible time lag of ca. 1-4 ka between biomarker formation and deposition, this indicates delayed Holocene reforestation in the catchment compared with western and central Europe, in agreement with regional pollen studies. The subsequent decline of deciduous trees/shrubs could be linked to human activity in the catchment during the late Holocene. (ii) Leaf waxes in floodplain paleosols indicate local grass/herb dominance throughout the Holocene, which is possibly caused by long-lasting local human activity.