Presented by Luis Miguel Acevedo-Soto, a recipient of the NOAA Ernest F. Hollings Scholarship

In this lecture, Luis will share the research he carried out over the past several weeks, focusing on freshwater acidification in the Great Lakes, a critical and understudied environmental issue.

Short description:

The Great Lakes represent one of the most extensive and critical freshwater ecosystems on the planet, containing nearly 20% of the world’s surface freshwater. Their ecological significance is reflected in their high biodiversity, while their economic value supports key sectors such as fisheries, transportation, and tourism. However, Lake Huron and the other Great Lakes are subject to increasing environmental stressors, including rising atmospheric CO2 concentrations, land-use changes, invasive species, harmful algal blooms, hypoxia, and the decline of native biodiversity, all of which threaten its biogeochemical stability.

In response, the Thunder Bay National Marine Sanctuary (TBNMS), in collaboration with the Great Lakes Environmental Research Laboratory (GLERL), is conducting a long-term acidification monitoring program focused on establishing a baseline for pH and related biogeochemical parameters. Water samples are collected at seven fixed locations, which are also archaeological shipwreck sites. These locations provide a unique opportunity to monitor environmental change within a historically significant context. In situ measurements of temperature, conductivity, and depth are taken using a handheld conductivity-temperature-depth (CTD) profiler, and samples are filtered through 47 um membranes. Laboratory analysis at GLERL employs high-precision pH electrodes and geochemical modeling to generate spatial distribution maps of pH levels.

This research seeks to detect gradual acidification in Lake Huron, which mirrors ocean trends. The resulting baseline data will be critical for identifying future chemical changes and guiding adaptive conservation strategies. By integrating environmental monitoring with cultural protection, this work supports the mission of TBNMS to preserve both ecological integrity and maritime history for future generations.

This lecture will take place at the Great Lakes Maritime Heritage Center at 12pm on Wednesday, July 23rd.  This is a free event and open to all.