Physical Sciences and Mathematics Commons^™

Unmanned Aircraft Systems For Precision Meteorology: An Analysis Of Gnss Position Measurement Error And Embedded Sensor Development, Karla S. Ladino

Theses and Dissertations--Biosystems and Agricultural Engineering

The overarching objective of this research was to enhance our comprehension of the three-dimensional precision of meteorological measurements obtained using small unmanned aircraft systems (UAS). Two complimentary experiments were conducted to achieve this objective.

The first experiment entailed the development and implementation of a system to determine the global navigation satellite system (GNSS) position accuracy on a UAS platform. This system was utilized to assess the static and dynamic accuracy of L1 and L1/L2 GNSS receivers in real-time kinematic (RTK) and non-RTK fix modes. Adjusted two-sample t-tests revealed significant differences in horizontal and vertical error between RTK and non-RTK receivers …

Exploration Of Lignin-Based Superabsorbent Polymers (Hydrogels) For Soil Water Management And As A Carrier For Delivering Rhizobium Spp., Toby Adjuik

Theses and Dissertations--Biosystems and Agricultural Engineering

Superabsorbent polymers (hydrogels) as soil amendments may improve soil hydraulic properties and act as carrier materials beneficial to soil microorganisms. Researchers have mostly explored synthetic hydrogels which may not be environmentally sustainable. This dissertation focused on the development and application of lignin-based hydrogels as sustainable soil amendments. This dissertation also explores the development of pedotransfer transfer functions (PTFs) for predicting saturated hydraulic conductivity using statistical and machine learning methods with a publicly available large data set. A lignin-based hydrogel was synthesized, and its impact on soil water retention was determined in silt loam and loamy fine sand soils. Hydrogel treatment …

Assessing Machine Learning Utility In Predicting Hydrologic And Nitrate Dynamics In Karst Agroecosystems, Timothy Mcgill

Theses and Dissertations--Biosystems and Agricultural Engineering

Seasonal hypoxia in the Gulf of Mexico and harmful algal blooms experienced in many inland freshwater bodies is partially driven due to excessive nitrogen loading seen from agricultural watersheds. Within the Mississippi/Atchafalaya River Basin, many areas are underlain with karst features, and efforts to reduce nitrogen contributions from these areas have had varying success, due to lacking a complete understanding of nutrient dynamics in karst agricultural systems. To improve the understanding of nitrogen cycling in these systems, 35 months of high resolution in situ water quality and atmospheric data were collected and fed into a two-hidden layer extreme learning machine …

Evaluating The Biotic Condition Of Restored Streams In Kentucky’S Inner Bluegrass Region, Charles Cole Crankshaw

Theses and Dissertations--Biosystems and Agricultural Engineering

Numerous stream restoration projects have been implemented in Kentucky’s Inner Bluegrass region to offset anthropogenic impacts. These projects range from full channel realignments to volunteer-led riparian installations. To assess the ability of said projects to restore stream habitat and biota, full restoration (n=12) and riparian (n=6) sites were compared to reference (n=6) and disturbed (n=12) sites using RBP and SVAP protocols, macroinvertebrate samples, and geomorphology. General trends for SVAP, RBP, and BI scores, starting with highest habitat or biotic quality, were reference sites, full and riparian restoration sites, then disturbed sites. The number of EPT taxa, another indicator of biological …

Quantifying Nitrogen Fate In Karst Agroecosystem Streams Of Central Kentucky: Development And Application Of Numerical Modeling And Insight From High-Resolution Sensors, Nolan Lewis Bunnell

Theses and Dissertations--Biosystems and Agricultural Engineering

In-stream fate of nutrients in karst agroecosystems remains poorly understood, despite the known impact of karst on water resources at local to global scales. In the Inner-Bluegrass region of central Kentucky, heterogeneity of karst maturity, flow pathways, and nutrient sources adds to the complexity of quantifying nutrient dynamics, thus requiring novel monitoring and modeling approaches. The significance of these streams is recognized given spring/surface water confluences have been identified as hotspots for biogeochemical transformations. In slow-moving streams high in dissolved inorganic nutrients (particularly dissolved inorganic nitrogen (DIN) and dissolved reactive phosphorus (DRP)), benthic and floating aquatic macrophytes are recognized to …

Development Of Techniques For Assessing And Restoring Streams On Surface Mined Lands, Whitney Cole Blackburn-Lynch

Theses and Dissertations--Biosystems and Agricultural Engineering

Surface mining is a commonly used method for extracting coal in the Appalachian Coalfields of the U.S. This mining practice produces excess spoil or overburden, which is often placed in adjacent valleys resulting in the creation of valley fills. These valley fills bury headwater streams, which in turn can negatively impact downstream ecosystems. In 2008, the University of Kentucky designed and constructed 1,020 m of ephemeral, intermittent and headwater streams on an existing valley fill (Guy Cove) as a proof-of-concept. The goal of the project was to evaluate whether or not a stream recreation could occur on mined lands, particularly …

Using Gis To Delineate Headwater Stream Origins In The Appalachian Coal-Belt Region Of Kentucky, Jonathan A. Villines

Theses and Dissertations--Biosystems and Agricultural Engineering

Human activity such as surface mining can have substantial impacts on the natural environment. Performing a Cumulative Hydrologic Impact Assessment (CHIA) of such impacts on surface water systems requires knowing the location and extent of these impacted streams. The Jurisdictional Determination (JD) of a stream’s protected status under the Clean Water Act (CWA) involves locating and classifying streams according to their flow regime: ephemeral, intermittent, or perennial. Due to their often remote locations and small size, taking a field inventory of headwater streams for surface mining permit applications or permit reviews is challenging. A means of estimating headwater stream location …