Early-Holocene to present palaeoenvironmental shifts and short climate events from the tropical wetland and lake sediments, Kukkal Lake, Southern India: Geochemistry and palynology

Abstract

The Kukkal basin, Tamil Nadu, India, receives most of its rain from the southwest monsoon. A sediment core from Kukkal Lake, preserves a continuous sediment record from the Early Holocene to present (9000 yr BP to present). The present lake is artificial, situated at an elevation of ~1887 m a.s.l.,, in a small basin that appears to have alternated between a and wetland depositional environment. Climate proxies, including sediment texture, TOC, Total Nitrogen (TN), C/N, pollen and geochemical composition indicate a steady progression to wetter conditions, with two stepwise changes at about 8000, and between 3200 and 1800 yr BP. The change at 8000 yr BP appears to correspond to a brief (100-150 yr) dry spell to about 8000 yr BP, followed by grassland with palms, the appearance of ferns just prior to 3200 yr BP, and the establishment of forest between 3200 and about 1800 yr BP.

A multi-proxy reconstruction of the late Holocene climate evolution in Lake Bolgoda, Sri Lanka

“…The first wet phase between ~3000 and 2400 cal yr BP recorded in the Bolgoda Lake coincides with other regional studies including the Horton Plains (Premathilake and Risberg, 2003) and various Indian lakes such as the Pookude Lake (Veena et al, 2014a), Kukkal Lake (Rajmanickam et al, 2016), Lonar Lake (Prasad et al, 2014) and Pokharan Lake (Roy et al, 2009;Fig. 5).…”

“…Wang et al, 2012) and efforts have been taken to correlate this trend with other regional palaeoclimate records from southern India (e.g. Rajmanickam et al, 2016).…”

Holocene palaeoenvironmental records from the high-altitude Wular Lake, Western Himalayas

“…Millennial to centennial scale climate changes as observed in the Wular Lake sediments have also been documented by other studies from the Himalayan region (Babeesh et al, 2019; Demske et al, 2009; Khan et al, 2018; Lone et al, 2019; Rawat et al, 2015; Srivastava et al, 2017), in south Indian lakes and deltas (Achyuthan et al, 2016; Ponton et al, 2012; Rajmanickam et al, 2016; Sarkar et al, 2015), marine sediment records (Bond et al, 1997; Cullen et al, 2000; Gupta et al, 2003; Nagasundaram et al, 2014; Orme et al, 2018; Staubwasser et al, 2003), ice core records (Grootes and Stuiver 1997; Stuiver et al, 1995; Thompson et al, 1997), and speleothem records (Cai et al, 2010; Fleitmann et al, 2003; Lone et al, 2014; Smith et al, 2016; Wang et al, 2005; Yadava et al, 2004). These palaeoclimate records provide an integrated record that includes short and extreme dry/cool events such as at 10,300 yr BP, 8200 yr BP, 6300 yr BP, 4200 yr BP and 600–400 yr BP during the Holocene.…”

Temperature and Monsoon Tango in a Tropical Stalagmite: Last Glacial-Interglacial Climate Dynamics

“…Hence, studies based on various physical and chemical proxies in a range of different climate archives such as lakes, rivers, peat deposits, and stalagmites retrieved from the core monsoon zone have been investigated to trace the variability in southwest monsoon. Changes in the intensity within the core monsoon zone have been assessed using grain-size variation, pollen assemblages 4 , 5 , δ 13 C shifts in vegetation 6 , diagnostic biomarkers 7 and δ 18 O shifts 8 – 10 . Notably, comparison of these different paleoclimate records indicates that periods of strongest and weakest monsoon winds were not always coupled to wettest or driest periods 4 .…”