Drs. Daniel Roelke and Jessica Labonté at Texas A&M University at Galveston have Study Published in Inland Waters Journal
The work of the “20 Lakes team” shows how algal blooms in inland lakes have the potential to disrupt key processes in the nitrogen cycle well downstream
The Texas A&M University at Galveston Department of Marine Biology’s “20 Lakes Team,” led by Drs. Daniel Roelke, Professor, Marine Biology, College of Marine Sciences & Maritime Studies, Texas A&M University at Galveston and Jessica Labonté, Associate Professor, Marine Biology College of Marine Sciences & Maritime Studies, Texas A&M University at Galveston, along with several graduate students, postdocs, and a Research Scientist, recently published a study in Inland Waters titled “Total microcystins reduce the activity of genes involved in nitrogen fixation and denitrification in lakes of the south-central USA”. The study shows that cyanotoxin-producing algal blooms in inland lakes have the potential to disrupt key processes in the nitrogen cycle. These disruptions may increase the amount of nitrogen transported to downstream coastal systems
“To understand what drives the health of our coastal estuaries, bays and seas, one must look holistically at the landscape, starting from headwaters of tributaries, continuing with inflows to our lakes, and culminating with discharges to our marine environments,” said Dr. Roelke. “In the western Gulf, nitrogen is often the primary nutrient limiting productivity; however, excessive inputs can have harmful effects. Elevated nitrogen loading may contribute to more frequent hypoxia and harmful algal blooms in coastal waters.”
While coastal systems can tolerate a certain degree of algae, when too many algae forms fueled by nitrogen gone wild, entire coastal ecosystems can be impacted. Too much nitrogen in the water can deplete oxygen levels leading to numerous impacts on marine life including fish kills. In other cases, algae blooms can block the sun from reaching the bottom of the water where sea grass and other food sources grow, leading to starvation events for marine life.
Understanding where nitrogen is introduced into the waterways and finding ways to stop it from impacting ecosystems downstream is an important element of maintaining healthy marine environments.
“Cyanobacteria blooms will increase in frequency and magnitude with continued changes in our climate, as will the impacts of the cyanotoxins produced by these blooms,” said Dr. Roelke. “The ability of microbes to shape entire ecosystems continues to amaze us.”
The work of the “20 Lakes team” was funded by the US Army Corps of Engineers with a $1.5 million grant. Dr. Roelke served as the lead Principal Investigator and Dr. Labonté served as the co-Principal Investigator.
To learn more about the findings, the full article can be found here: https://www.tandfonline.com/doi/full/10.1080/20442041.2025.2602547
