Late Quaternary hydroclimatic reconstruction based on compound-specific hydrogen isotope ratios in lake sediments, southeastern Amazonia

• Grant number: 17/20062-1
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate
• Effective date (Start): May 07, 2018
• Effective date (End): November 06, 2018
• Field of knowledge: Interdisciplinary Subjects
• Principal Investigator: Luiz Carlos Ruiz Pessenda
• Grantee: Luiza Santos Reis
• Supervisor: Ioanna Bouloubassi
• Host Institution: Centro de Energia Nuclear na Agricultura (CENA). Universidade de São Paulo (USP). Piracicaba , SP, Brazil
• Research place: Université Pierre et Marie Curie (Paris 6), France
• Associated to the scholarship: 15/25744-8 - Interdisciplinary Pleistocenic reconstitution of lake deposits of Serra Sul of Carajás, Southeastern Amazon region, BP.DR

Abstract

Several previous studies have confirmed the importance of the D/H ratio [deuterium (2H or D) and hydrogen (H)] in compound-specific extracted from lacustrine sediments such as paleohydrological proxies. Innovative analytical methods demonstrated that the hydrogen-isotopic composition of individual lipids from aquatic and terrestrial organisms is strongly correlated with rainwater composition used in the plant's biochemical processes. The relative abundance of hydrogen isotopes in rainfall, in turn, is directly linked to the flow of water in the hydrological cycle. Thus, oscillations in d2H values recorded, for example, in plant leaf waxes and/or lacustrine sediments are essential for understanding changes in atmospheric dynamics over geological time. However, even though it was recognized as a promising tool in paleohydrological reconstitution studies, few studies containing isotopic data (d2H, d13C) of lipids extracted from lacustrine sediments was performed in South America. Thus, the present study aims to analyze compound-specific D/H ratio in lacustrine sediments in eastern Amazonia, in order to obtain information about paleohydrological and paleoclimatic regional variations along the late Quaternary and its paleoenvironmental implications.