Abstract
Human activities have led to excessive nutrient enrichment which is greater than lake systems can naturally assimilate. This process is known as eutrophication and it is driving significant algae growth resulting in the more common release of harmful toxins. Utah Lake, located in Utah County, UT is one such water body that even after major reductions in anthropogenic phosphorus influent, continues to experience frequent, harmful algal blooms. The extent to which natural processes, like atmospheric dust deposition and sediment recycling, contribute to the lake's phosphorus budget is still poorly understood.
To address this gap of knowledge, this study quantified phosphorus inputs from dust and analyzed porewater geochemistry from three lake sediment freeze cores. Dust collected with active air samplers showed no significant attenuation along the southwest–northeast transect as previously hypothesized, although phosphorus solubility declined in the same direction possibly indicating the significance of anthropogenic dust contribution. Porewater geochemistry revealed evidence of diverse porewater movement, exhibiting both groundwater-driven advection and diffusive release of phosphorus from the lake sediments. Using Fick’s law, the estimated lake sediment diffusion contributes an average of 790 mT yr⁻¹ (5.7 mg P m⁻² d⁻¹), representing approximately 68% of total phosphorus loading to the lake.
These results highlight dust and lake sediment recycling as complex, understudied nonpoint sources of phosphorus. By clarifying their magnitude and mechanisms, this study advances understanding of nutrient dynamics in Utah Lake and informs for more effective strategies in eutrophication management.
Degree
MS
College and Department
Computational, Mathematical, and Physical Sciences; Geological Sciences
Rights
https://lib.byu.edu/about/copyright/
BYU ScholarsArchive Citation
Smith, Kristen E., "The Role of Dust Inputs and Sediment Phosphorus Diffusion Into Utah Lake, Utah, United States of America" (2025). Theses and Dissertations. 11076.
https://scholarsarchive.byu.edu/etd/11076
Date Submitted
2025-12-18
Document Type
Thesis
Keywords
eutrophication, algal, water quality, atmospheric deposition, sediment flux
Language
english