Authors: Aljexi Olsen, Hali Lukacs
Mentors: Eddy Cadet
Insitution: Utah Valley University
Utah Lake is the third-largest freshwater body west of the Mississippi River and serves as a vital resource for just over 600,000 Utah Valley residents through agriculture, residential and recreational purposes. In addition to its utility, Utah Lake provides a haven for biodiversity for numerous species within its wetlands. Despite its utility and importance, the lake faces two significant challenges in the form of Trace Metal (TM) pollution and the encroachment of invasive plant species known as Phragmites australis (P. australis). Despite considerable investments of time, money, and resources by various state agencies to address these concerns, their success has been limited due to the agency’s isolated efforts for these large multifaceted issues. TM, though naturally occurring in the environment, has been found to be toxic to both people and the ecosystem when at elevated levels. P. australis, is a robust and fast-growing macrophyte, possessing remarkable adaptability to and tolerance for poor soils, enabling it to rapidly outcompete native species. Due to P. australis resilience and aggressive nature, many colonies have grown around the lake regardless of soil conditions. Studies have shown that P. australis has been utilized for remediation purposes around water bodies by extracting TMs from sediment. While P. australis must be addressed, can it be used as part of the solution by identifying TM polluted areas? This study aims to discern the variety in TM absorption by P. australis in both unpolluted and polluted sites in the wetlands surrounding the hyper-eutrophic Utah Lake. We selected nine sites around Utah Lake, considering their land use and proximity to pollution sources. At each site, three replicate samples encompassing P. australis, soil, and water were collected. These samples underwent a meticulous process, including washing, weighing, grounding, sieving, acid digesting using a CEM MARS 6, and analysis for TM content within an ICP-MS. Our preliminary findings reveal that in both unpolluted and polluted sites, soil concentrations of As and Cd exceeded background levels (11.73, 1.53 in unpolluted sites, and 27.47, 6.63 in polluted sites, respectively). Notably, in select polluted sites, such as UVU, P. australis displayed a remarkable capacity to hyper-accumulate As, with a transfer factor of 167.14% compared to the lowest unpolluted sites, like Lindon, which showed a rate of about 10%. Across all sites, the accumulation of Cr was relatively consistent (ranging from 17.13 to 19.7 ppm), irrespective of biomass. The examination of TM concentrations, transfer factor rates, and TM accumulation based on biomass suggests that P. australis may serve as a valuable biomarker for identifying TM-polluted sites. This research holds significant relevance, as it could offer state agencies a swift and effective means to pinpoint TM-polluted areas. Moreover, the areas where P. australis is thriving may be leveraged for phytoremediation efforts in TM-contaminated sites, providing an environmentally friendly solution to address this pressing concern.