Phytoplankton community dynamics and their role in naphthenic acid transformation within a constructed wetland system treating oil sands process-affected water

the precise role of phytoplankton in influencing Naphthenic Acid Fraction Compounds (NAFC) transformation and degradation within Constructed Wetland Treatment System (CWTS) remains poorly understood. Characterizing the composition and structure of phytoplankton communities in CWTS specifically designed to treat oil sands process-affected water (OSPW) is a critical first step toward optimizing these systems for effective mine closure. To address this knowledge gap, we assessed the phytoplankton community associated with a pilot CWTS treating OSPW. Specifically, we examined how vegetation (cattail and sedge) in shallow areas and water depth (deep vs. shallow areas) influenced these communities. Additionally, we explored the relationship between water chemistry variables and phytoplankton dynamics and assessed the role of phytoplankton in contributing to changes in the NAFC heteroatoms present in OSPW during an operational season. These results help to inform CWTS optimization and support the development of effective, bioremediation-based strategies for OSPW.