Nutrient cycles of shallow, eutrophic, wind-exposed lakes are influenced predominantly by sediment resuspension because resuspended sediments can increase turbidity and reintroduce nutrients directly to the euphotic zone. Research presented in this dissertation outlines modeling and analytical approaches for quantitative assessment of sediment resuspension linkages to nutrient cycles in the Salton Sea. The Salton Sea is a shallow, highly saline, eutrophic, wind-exposed terminal lake, located in the southern desert of California, USA. This research includes the development of a hydrodynamic and water quality model, DLM-WQ, combined with a simple sediment resuspension model. The resulting model was based on conceptual models representing the unique biogeochemistry of the Sea. The model strongly suggests that sediment resuspension nutrients in both particulate and dissolved form is the dominant factor in the Sea's nutrient cycling.

To quantify sediment resuspension in a shallow lake, a field campaign was conducted during non-stratified conditions of the Salton Sea. Measurements were made with an array of optical backscatter sensors (OBS) synchronized with a wave and current profiling instrument (AWAC), a thermistor chain and meteorological data for four months. The analysis and interpretation of the data allowed the establishment of an unprecedented framework for the computation of sediment resuspension in lakes.

Referring to data analysis, sediment resuspension models representing sediment characteristics of the Salton Sea were combined with DLM-WQ and successfully applied to the lake. The calibrated outputs of the resulting models were compared with measured data by using statistical and graphical evaluation methods. Based on these comparisons, DLM-WQ with an extended relation of Garcia and Parker, originally developed for open channel flows, was considered the best model to describe measured data. The resulting model provides a practical means to quantify impacts of the proposed alternatives that will change sediment resuspension patterns for a future Sea on water quality.

Results of this research provide a scientifically sound base for quantitative analysis of sediment resuspension linkages to nutrient cycles within the Sea. Advances made in this research will enhance understanding of nutrient cycles in shallow, eutrophic lakes and thereby aid in securing practical solutions for preservation and protection of their ecosystem.