By Jamie Martin
Michigan State University (MSU) researchers recently studied how climate change interacts with human activities to affect the health of lakes across the United States.
They found that increased algae growth, known as algal blooms, is not solely caused by climate change but is also influenced significantly by human-related nutrient pollution from agriculture and urban areas.
The MSU research team, led by Professor Patricia Soranno, analyzed 34 years of data on over 24,000 U.S. lakes using satellite imagery and open-access government resources.
They specifically measured chlorophyll levels to estimate the number of algae in lakes, uncovering important patterns related to climate change and human disturbances.
Soranno explained, “Our research demonstrates that the relationship between climate change and algal biomass is more complex than expected. While climate is a significant driver of algal biomass, we found that the impacts are not always gradual or predictable. To effectively manage and protect lakes, we need to study these effects in many different local and regional contexts.”
The study identified that about one-third of lakes experienced algae changes directly linked to climate. Surprisingly, most of these changes were abrupt and temporary rather than gradual and sustained. Such sudden changes have typically gone unnoticed in traditional monitoring methods.
This data-intensive approach also uncovered variability in climate-driven algal responses that depend on environmental conditions and the level of human disturbance.
Lakes with low to moderate human impacts were more likely to respond to climate, while lakes already under heavy human pressures, like increased nutrient input from agriculture, were less likely linked to climate.
Understanding these interactions is critical because algal blooms can produce toxins harmful to people, wildlife, and local economies.
The research provides valuable insights for policymakers and communities aiming to protect and manage lakes more effectively. This study emphasizes the importance of considering both climate factors and human activities in lake management strategies nationwide.
Photo Credit: michigan-state-university-msu
Categories: National