Late-Holocene palaeoenvironmental reconstruction from a lake in the Amazon Rainforest-Tropical Savanna (Cerrado) boundary in Brazil using a multi-proxy approach

As an ecotone, the region between Amazon Rainforest and Tropical Savanna (Cerrado) biomes is, by definition, more susceptible to climate change. Therefore, understanding palaeoenvironmental dynamics is essential address future responses of such transition areas climatic fluctuations. In this context, we present a new sediment record for Late-Holocene retrieved from Barro-Preto, currently oxbow lake located in ecotone at southern Brazilian border. Our multi-proxy data include carbon nitrogen isotopes, as well bulk TOC, chlorophyll derivatives, grain-size microcharcoal analyses, all anchored on radiocarbon-dated chronology. The sedimentary process recorded Barro-Preto Lake responded both local regional dynamics. It was influenced river excursions associated precipitation changes activation palaeochannel connecting main-stem lake. This evidenced presence different colour lithology laminations accompanied coarser sediments also conditions known influence region. Depositional processes linked cycle stages were important explain verified record, endorsing use formation palaeoclimatic reconstructions. indicated rising humidity trend, reflected progressive increase lacustrine productivity, accordance other studies carried out concerning Late-Holocene, with southward displacement Intertropical Convergence Zone. Despite dry episodic events during charcoal data, coherent studies, albeit exhibiting increased intensity, suggesting that transitional nature environment might have susceptibility fires.