Battling toxic blooms

Graduate student Tanten Buszka works in the tracer field

Graduate student Tanten Buszka works in the tracer well field in Charlotte County.

Harmful algal blooms (HABs) occur when colonies of algae grow out of control, producing hazardous toxins that threaten humans and aquatic life – and while Michigan has faced numerous HAB events, the problem is not unique to our state’s waterways.

In 2017, a team of WMU students led by Drs. Mohamed Sultan and Matt Reeves launched a research project that examines HABs along the Charlotte County, Florida coastline. Funded in part by the Enterprise Charlotte Foundation, the study aims to: 1) understand the factors and conditions that control the occurrences of the blooms, and 2) develop efficient, cost-effective and automated systems for mapping and predicting them.

“To accomplish these goals, we first extract statistical relationships that relate historical bloom events in Charlotte County and surrounding waters to observations extracted from satellite imagery on bloom days or acquired a few days earlier,” Sultan says. “We then look for similar observations to map and predict bloom occurrences.”

Using the researchers’ methods to forecast and identify the factors controlling HABs could help Charlotte County policymakers implement measures to reduce or mitigate the blooms.

“The beauty and biological productivity of Charlotte Harbor, such as fishing and wildlife, is the primary reason people live in this area,” Reeves adds. “Environmental degradation through pollution and eutrophication (algal blooms caused by excess nutrients) could have devastating impacts on the local community, so it’s important to understand the factors that contribute to them.”

Reeves says the HABs in Charlotte County are caused by excess nitrogen entering groundwater through the area’s septic systems. His research focuses on characterizing the flow and transport properties of the surficial aquifer system to better understand nitrogen loading into the harbor.

“The conversion of septic systems to sewers is underway, which will dramatically reduce nitrogen into Charlotte Harbor,” he says. “However, the full septic-to-sewer conversion will take over three decades. Our work on the characterization of ground water velocities and the surficial aquifer system can be used to identify areas within Charlotte County that should receive higher priority for sewer conversion.”

To learn more about WMU researchers' work in freshwater science and sustainability, view the 2018 Arts and Sciences Magazine.