Unmasking the succession and driving mechanisms of marine biological communities using sedimentary DNA: Case studies from Antarctica and Macao

• Grant number: 25/11793-9
• Support Opportunities: Regular Research Grants
• Start date: January 01, 2026
• End date: December 31, 2028
• Field of knowledge: Physical Sciences and Mathematics - Oceanography - Biological Oceanography
• Principal Investigator: Paulo Yukio Gomes Sumida
• Grantee: Paulo Yukio Gomes Sumida
• Principal researcher abroad: Ybing Ma
• Institution abroad: Macau University of Science and Technology ,
• Host Institution: Instituto Oceanográfico (IO). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• City of the host institution: São Paulo
• Associated researchers: Ke Shi ; Rodrigo Rodrigues Domingues ; Yanfu Wei

Abstract

Marine biodiversity is fundamental to the health and functioning of marine ecosystems. It directly supports a range of irreplaceable ecosystem services critical to human well-being, including food provision (e.g., fisheries), climate regulation (e.g., carbon sequestration), supporting services (e.g., nutrient cycling and primary production), and cultural services (e.g., coastal tourism and recreation). Highly diverse systems have greater functional redundancy, making them more resilient to potential disruptions However, marine biodiversity is experiencing rapid and unprecedented declines, now recognized as a key driver behind the degradation of over 60% of ecosystem services. Climate change-especially global warming-and intensifying anthropogenic activities, such as environmental pollution and coastal land reclamation, are the primary causes of this biodiversity loss, posing serious threats to the long-term sustainability of marine ecosystems. Biodiversity loss occurs across various spatial and temporal scales and often results from cumulative, long-term impacts that are difficult to detect using conventional monitoring techniques. To accurately determine the causes of biodiversity and ecosystem function loss, it is essential to quantify changes in biological, abiotic, and functional systems before, during, and after key environmental events. Marine sediments function as ecological archives, preserving biological and environmental signals that span from pre-anthropogenic baselines through periods of significant human impact. These sediments offer valuable insights into the temporal dynamics of biological communities, abiotic conditions, and ecosystem functions. We will use sedimentary DNA (sedDNA) collected with piston corer from distinct layers to reconstruct historical marine biodiversity across trophic levels to explore the long-term succession and assembly of marine sediment communities under dual stressors, i.e., climate change and anthropogenic impact. We propose a differential model for community construction processes based on stressor type. In the polar deep sea, climate warming is a deterministic force by compressing thermal niches, leading to low-diversity but functionally resilient communities. In contrast, coastal systems experience both deterministic filtering (e.g., through pollutant selection) and amplified stochasticity due to habitat fragmentation and trophic disruption. This framework allows for predictive modeling of biodiversity change under climate and pollution regimes. We aims to uncover the evolutionary trajectories and driving mechanisms of marine sediment communities under global climate change. By analyzing millennial-scale succession patterns recorded in ancient DNA from Antarctic deep-sea sediments and shallow, alongside decadal-scale biological responses to pollution gradients in the coastal waters of Macao, we will reconstruct the long-term dynamics of community assembly. Through comparative analysis of two distinct systems-climate-dominated Antarctic sediments and anthropogenically impacted coastal zones-we seek to identify the divergent mechanisms governing marine biodiversity patterns. By integrating multi-scale observational data, sediment DNA-based reconstructions, and machine learning prediction models, this research will clarify the pathways of biodiversity and functional shifts, ultimately contributing to a cross-regional, multi-stressor predictive model. The outcomes will provide a scientific foundation for the adaptive management of marine ecosystems facing climate and human pressures. (AU)