Biography：
Dr. Nina Bednaršek is a biological oceanographer and Senior Scientist at the Jožef Stefan Institute, Slovenia, specializing in the impacts of ocean acidification and multiple climate stressors on marine ecosystems. Her work integrates field observations, experimental biology, ecosystem modelling, and large-scale syntheses to assess biological vulnerability and develop thresholds relevant for fisheries and aquaculture risk assessment. She also leads research on marine carbon dioxide removal, with a focus on ocean alkalinity enhancement, evaluating its mitigation potential, ecological risks, and governance needs.
She has held research positions at NOAA’s Pacific Marine Environmental Laboratory, the University of Washington and has led multi-institutional projects in the North Pacific, Arctic, US West Coast, Adriatic, and Mediterranean. Internationally, she serves as a Lead Author for the IPCC Methodology Report on Carbon Dioxide Removal Technologies, Vice Chair of the IMBeR Executive Steering Committee, and Executive Committee member of the UN Decade Ocean Negative Carbon Emission (ONCE) Program.
Abstract：
Marine ecosystems are already experiencing unprecedented climate‑driven change, with ocean acidification emerging as a central pressure on ecologically and economically important calcifies and the services they underpin. Drawing on more than a decade of integrated work across the North Pacific, Arctic, US West Coast, Adriatic, and Mediterranean, I will first show how present‑day carbonate chemistry variability translates into biological vulnerability, using pelagic and benthic calcifies as well as aquaculture species as case studies. I will highlight how biological thresholds and large‑scale syntheses can be used to assess risks for fisheries and aquaculture, and to develop early‑warning indicators that support adaptive management.
Building on this foundation, I will then turn to marine carbon dioxide removal (mCDR), focusing on ocean alkalinity enhancement (OAE). I will discuss how mesocosm experiments and natural‑analogue studies can be used to constrain both the mitigation potential and ecological risks of OAE, emphasizing carbonate‑system dynamics, species‑specific sensitivity, and the conditions under which enhanced alkalinity might translate into durable carbon sequestration. Using recent work from the Adriatic and Mediterranean—including expert‑based assessments of governance and readiness—I will argue that OAE and other mCDR approaches should currently be treated as research‑first, precautionary options rather than deployment‑ready solutions, and outline what advances in experimentation, monitoring, and governance are needed to move forward responsibly.
The seminar will close by exploring how biological vulnerability assessments and mCDR research can be integrated into broader climate‑resilient ocean governance, and by identifying opportunities for collaboration with MEL and Xiamen University on organism‑to‑ecosystem‑scale assessments of both ocean acidification impacts and OAE interventions.
