Physical Sciences and Mathematics Commons^™

Enhancing Monthly Streamflow Prediction Using Meteorological Factors And Machine Learning Models In The Upper Colorado River Basin, Saichand Thota

All Graduate Theses and Dissertations, Fall 2023 to Present

Understanding and predicting streamflow along river basins is vital for planning future developments and ensuring safety, especially with climate change challenges. Our study focused on forecasting streamflow at Lees Ferry, a key location along the Colorado River in the Upper Colorado River Basin. We employed four machine learning models - Random Forest Regression, Long short-term memory, Gated Recurrent Unit, and Seasonal Auto-Regressive Integrated Moving Average; and combined historical streamflow data with meteorological factors such as snow water equivalent, temperature, and precipitation. Our analysis spanned 30 years of data from 1991 to 2020.

Our findings revealed that the Random Forest Regression …

An Examination Of The Effects Of Prey Density, Mortality, Nutrients, And Foraging Tradeoffs On A System With Inducible Defenses: An Empirical And Theoretical Approach, Benjamin C. Ralston Daniel

All Graduate Theses and Dissertations, Fall 2023 to Present

To grasp the functioning and stability of ecosystems, it is important to understand species interactions. With many ecosystems becoming more imperiled from urbanization and anthropogenic influences it is important to understand ways in which species can adapt to rapid changes in their environment. Phenotypic plasticity is one such tool at nature’s disposal to initiate rapid change, where species with the same genetic makeup can have different expressed traits depending on their environment. Inducible defenses are one such form of phenotypic plasticity in which prey can express different levels and forms of defense depending on the threat of predation present in …

The Effect Of Seed Mix Density And Composition On Wetland Plant Community Assembly In The Great Salt Lake Watershed, Elana Feldman

All Graduate Theses and Dissertations, Fall 2023 to Present

Wetlands provide important ecosystem services to society but are in danger across the globe partly due to the spread of invasive species (species that harm humans, the environment, or the economy). One species, Phragmites australis, is a widespread invader across the country, including in the wetlands of the Great Salt Lake and Utah Lake. Phragmites australis spreads widely and quickly outcompetes native species. In places where P. australis has already been removed, seeding wetlands helps block P. australis from returning. Native plants’ ability to prevent invasive species from entering the community is affected by many factors, but two that …

Informing Control Efforts For A Prolific Invasive Species: Characterizing Common Carp Spatio-Temporal Distribution And Evaluating The Impacts Of Gear Selectivity In Utah Lake, Rae Fadlovich

All Graduate Theses and Dissertations, Fall 2023 to Present

Management programs that aim to reduce the consequences of invasive species are often challenged by populations that can rapidly recover from removal efforts. Selectivity, the relative impact of harvest on different size classes, can contribute to population recovery when younger fish are not effectively targeted. In Utah Lake, the location of one of the world’s largest freshwater fish control programs, managers have been attempting to control the common carp (Cyprinus carpio, hereafter “carp”) population since 2009 but efforts have been hindered by the use of selective fishing gears. I conducted a lake-wide field study to gain insights into …

Channel Response To Flow Augmentation: Diamond Fork River, Ut, Diane E. Wagner

All Graduate Theses and Dissertations, Fall 2023 to Present

A river’s physical features and channel dimensions are determined by the water and sediment supplied to it. The Diamond Fork River, located in central Utah—received large trans-basin diversion flows from 1915-2003, providing an exceptional opportunity to explore the response of a river to a large increase in flow.

Our project goals were to describe 1) channel response to this large and long artificial flow augmentation and 2) how the channel recovered after the removal of the diversion flows. The objective of this thesis is to document the channel condition throughout the 20^th century to present day as a basis …

Impacts Of Lake Elevation Decline On Tui Chub, A Critical Forage Species For Lahontan Cutthroat Trout In Pyramid Lake, Nevada, Usa, Sarah Barnes

All Graduate Theses and Dissertations, Fall 2023 to Present

Lake level decline affects lakes worldwide, changing the availability and character of nearshore habitat used by fish to spawn, and increasing total dissolved solids (TDS), similar to salinity, a factor that negatively impacts fish health. Lake level decline can affect different lakes in different ways, but typically when lake level declines significantly, there is less nearshore habitat overall, and what nearshore habitat remains has less diverse habitat for fish. We investigated whether both impacts of lake level decline may be causing declines of Tui Chub Siphateles bicolor, a large minnow native to Pyramid Lake that spawns in nearshore habitat. …