Understanding lipid signals in modern sediments of tropical South American rivers

• Grant number: 21/15101-3
• Support Opportunities: Scholarships abroad - Research Internship - Post-doctor
• Effective date (Start): April 01, 2022
• Effective date (End): July 31, 2022
• Field of knowledge: Physical Sciences and Mathematics - Geosciences - Geology
• Principal Investigator: Cristiano Mazur Chiessi
• Grantee: Dailson José Bertassoli Junior
• Supervisor: Enno Schefuß
• Host Institution: Escola de Artes, Ciências e Humanidades (EACH). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Research place: University of Bremen, Germany
• Associated to the scholarship: 19/24977-0 - Environmental signals recorded in modern sediments of tropical South American rivers, BP.PD

Abstract

Concerns about human-induced climate change have promoted efforts to understand how tropical ecosystems were affected by climate oscillations in the past. To date, a significant part of the available information has been obtained by analyzing organic molecular proxies in marine sediments. An appropriate interpretation of these proxies, however, depends on the understanding of how organic sediments are transported and transformed during their pathway from source to sink. Here we will prepare, analyze and interpret compound-specific carbon and hydrogen isotope signatures from long-chain n-alkanes and the distribution of glycerol dialkyl glycerol tetraethers of riverbed and suspended sediment samples from two major South American river systems, the Amazon and São Francisco Basins. The obtained results will elucidate the effects of spatial and seasonal variability on the biomarker signatures reaching the Atlantic Ocean and provide an important framework for the interpretation of paleoenvironmental reconstructions based on marine sediment cores retrieved off tropical South America. The internship will be developed at the world-leading institution MARUM - Center for Marine Environmental Sciences (University of Bremen, Germany) in collaboration with Dr. Enno Schefuß, a key scientist in the development and application of carbon and hydrogen isotopes from long-chain n-alkanes in paleoenvironmental studies. (AU)