The fate of Holocene blue carbon in the Yangtze and Amazon coastal wetlands in response to precipitation and sea level changes

• Grant number: 22/08025-1
• Support Opportunities: Research Program on Global Climate Change - Regular Grants
• Start date: January 01, 2023
• End date: December 31, 2025
• Field of knowledge: Physical Sciences and Mathematics - Geosciences - Geology
• Agreement: National Natural Science Foundation of China (NSFC)
• Principal Investigator: André Oliveira Sawakuchi
• Grantee: André Oliveira Sawakuchi
• Principal researcher abroad: Xiaomei Nian
• Institution abroad: East China Normal University (ECNU), China
• Host Institution: Instituto de Geociências (IGC). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated researchers: Cristiano Mazur Chiessi ; Dailson José Bertassoli Junior ; Dongqi Wang ; Fabiano do Nascimento Pupim ; Henrique Oliveira Sawakuchi ; Marília de Carvalho Campos Garcia ; Qianli Sun ; Vania Neu ; Weiguo Zhang ; Yan Liu ; Yunping Xu

Abstract

This proposal aims to improve our understanding about the accumulation and emission of carbon in coastal wetlands developed near the mouth of large rivers. These areas have a crucial role for the carbon budget in continental and marine ecosystems. Thus, the presented proposal is in line with research theme 4 of funding direction 2 listed in the project description, namely "Carbon sink processes of sea shelf" under "The impacts of climate change on ecosystems, including coastal areas, agroforestry ecosystem and human health and their response". Coastal wetlands at the mouth of large rivers may behave as important carbon sinks or sources of greenhouse gases (GHG) to the atmosphere. However, there is still a lack of understanding of how carbon burial processes and GHG emissions in wetlands of large rivers will react to future precipitation change and sea level rise due to global warming. The (sub)tropics experienced significant climate and sea level changes during the Holocene. Hence, investigating carbon sources and sinks during this period is key to understand how coastal wetlands carbon burial will react to future climate change. The Yangtze and Amazon Rivers are the largest rivers in Asia and South America, respectively, both being affected by (sub)tropical monsoon, whose precipitation patterns are expected to change under global warming. Here we will perform a comparative study of sedimentation of organic material and GHG produced through organic-sediment biodegradation in coastal wetlands of the Yangtze and Amazon Rivers with the aim of understanding how the carbon budget of these systems will respond to future climate change. Based on a reliable chronological framework of Holocene sediments in coastal wetlands of the Yangtze delta and Amazon estuary, this study intends to explore the relationship between Holocene climate and sea-level change, wetland morphological evolution and organic carbon burial flux. Our study will provide scientific support for the assessment of blue carbon sink under future global climate change. (AU)