Elemental Composition and Isotopic Signature of Particulate Organic Matter in Admiralty Bay, King George Island, Antarctica.

• Grant number: 24/07616-1
• Support Opportunities: Scholarships in Brazil - Master
• Start date: April 01, 2025
• End date: September 30, 2026
• Field of knowledge: Physical Sciences and Mathematics - Oceanography - Chemical Oceanography
• Principal Investigator: Cesar de Castro Martins
• Grantee: Jamile Tamer Nasser
• Host Institution: Instituto Oceanográfico (IO). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

The Antarctic Peninsula holds significant environmental and climatic importance due to its freshwater reserves and extreme weather conditions, in additon is remote from major human activities, facilitating the study of Earth's ecological and evolutionary processes with minimal human interference. Research aims to comprehend organic matter (OM) processes across various Antarctic environments, identifying sources and oceanographic influences on its distribution and seabed deposition by analyzing elemental composition. The studyof OM in marine settings involves parameters like total organic carbon (TOC), total nitrogen (NT), TOC/NT ratio (C/N), and carbon (´13C) and nitrogen (´1N) isotopic ratios. This project focuses on Admiralty Bay, King George Island, Antarctic Peninsula, here environmental changes resulting from progressive global warming in recent decades require greater understanding. The aim is to determine OM elemental and isotopic parameters in Suspended Particulate Matter (SPM) samples across different Admiralty Bay sites during four periods (spring, late spring, summer, and late summer) over two campaigns (2023/2024 and 2024/2025). The goal is to assess multiproxy variability in the face of different environmental conditions that act on the biogeochemical cycle of local particulate organic carbon on a short time scale (monthly) and on an annual scale. Additionally, it aims to compare elemental and isotopic composition between SPM and sediment samples from the same campaigns to understand OM transfer mechanisms between compartments. The results of this project should contribute to a greater understanding of local biogeochemical cycles and environmental changes across different time frames.