Early-Late Holocene Paleoenvironment Shifts: Berijam and Kukkal Lakes

Two lakes situated in the Palani Hills, Tamil Nadu, India, were investigated for reconstructing the fluctuations in the south-west monsoon since the Early Holocene period. Sediment cores were raised from both the lakes and radiocarbon dated. The ages reveal non-linear phases of deposition. Berijam lake core is dated from 2400 yrs BP to the present. Older ages were obtained for the Kukkal lake sediment core (9000 yrs BP to Present). Wet, Holocene climatic optimum (9000 yrs to 5000 yrs BP) was noted in the Kukkal sediment core. However, from 5000 yrs BP to present, drier conditions prevailed due to the decline in south-west monsoon intensity. During this long dry period, several wetter events of shorter duration occurred. Medieval warm period and Little Ice Age events were noted in the Berijam lake core. The C/N ratio of Berijam and Kukkal lake sediments indicate that the organic carbon is mainly sourced from the lacustrine algae and aquatic weeds.Pollen data exhibit savanna vegetation around the Kukkal Lake during the Early Holocene, but shifting to more open vegetation cover because of dry environment since the Middle Holocene to present.