Molecular fossils in a Pleistocene river terrace in southern China related to paleoclimate variation

The red paleosols (Oxisols) in southern China provide a record of global climate oscillation during at least the last 0.80 Ma. Here we present a correlation between the marine oxygen isotope record (stage 11–21) and the paleosol molecular fossil signature in the fourth Xiushui river terrace in southern China. Temporal variations seen in two molecular ratios—C15–21/C22–33 n-alkanes and pristane to phytane (Pr/Ph)—down the paleosol profile are postulated to have arisen from variations in biological input and subsequent pedogenesis in response to the changing strength of the East Asian summer monsoon climate. The preliminary findings suggest strong couplings among the soil, vegetation and climate, and provide a basis for a correlation between the terrestrial and oceanic records.