Daphne Panie

Experimental Evaluation of Buffering Strategies to Mitigate Ocean Acidification in Long Island Sound

Started Aug. 22, 2025

Abstract or project description

Ocean acidification is an alarming problem driven by the increasing amount of atmospheric CO2. When absorbed by the oceans, CO2 undergoes a series of reactions that lower the ocean's pH and endanger marine habitats. Buffering strategies to increase pH have been considered as a complement to the necessary reduction of atmospheric CO2 concentration. This study experimentally compares the effectiveness of natural (crushed coral and oyster) and chemical (sodium bicarbonate) buffers in mitigating ocean acidification. Using manually acidified Long Island Sound (LIS) saltwater, the effects of natural and chemical buffers, at different doses and applications, and under single or repeated acid shocks, were measured daily across a series of experiments. In addition, the health of different aquatic plant species was monitored when placed in buffered and unbuffered acidified water. It was hypothesized that buffers would help with recovery, with their particular strength and effectiveness depending on the dose, and that plants would help mitigate acidification through photosynthesis. Results showed that natural buffers supported long-term, stable pH recovery, while sodium bicarbonate caused the pH to quickly spike. The buffer's effect did not seem to weaken under repeated acidification. The impact of plants differed across experiments, and no concrete conclusions could be drawn. Atmospheric exchanges seemed to play a dominant role, shadowing the impact of buffers, although only after a certain time. This study helps scientists assess the effectiveness of different types of buffers and highlight areas for future research.