Author ORCID Identifier

Date Available


Year of Publication


Degree Name

Master of Science in Biosystems and Agricultural Engineering (MSBiosyAgE)

Document Type

Master's Thesis


Agriculture; Engineering


Biosystems and Agricultural Engineering

First Advisor

Dr. William Ford


As harmful algal blooms in regulated river systems have increased in the past decade, the importance of understanding sediment nutrients has also increased. Research linking nutrient processes and fine sediment dynamics to harmful algal blooms in confluence wetlands along regulated rivers has recently become apparent. However, the relationship between sediment nutrient dynamics in confluence wetlands has been understudied. Utilization of sediment fingerprinting, high-frequency water quality monitoring, and tracer unmixing mass-balance modeling, was able to suggest sediment N mineralization in Appalachia confluence riparian wetland was not a dominate source of nitrate downstream. Further measures of supplementary tracers and additional sediment sources were coupled with stable isotope unmixing modeling. The use of a dual-isotope unmixing method reduced uncertainty for majority of events where internal sediment sources were prominent. Potential sources are especially important to characterize when using stable isotope tracing techniques to continue the reduction of model uncertainty. Dual-isotope unmixing results process through mass-balance modeling demonstrated small tributaries may have larger depositional impacts on a confluence wetland rather than the localized regulated river, emphasizing the importance of nutrient reduction in small scale waterways. The use of this data significantly improves mass-balance unmixing modeling for confluence wetlands and implementation of floodplains in watershed management practices.

Digital Object Identifier (DOI)

Funding Information

This research was funded by the National Science Foundation Sensing and Educating the Nexus to Sustain Ecosystems (SENSE) 1632888 from 2019 to 2021.