Physical Sciences and Mathematics Commons^™

Soil Gypsum Content Analysis Of The Proposed Road Route Extension Of Fm 2185 In The Gypsum Plain, Culberson County, Texas, Chikaodili Ohakawa

Electronic Theses and Dissertations

Soils serve as the underlying substrate on which foundations for most structures are built. The properties of a soil type are therefore an important consideration in building engineered structures. Gypsic soils are problematic for construction of such structures. One of the main problems with gypsic soils is dissolution. Gypsum (CaSO₄·2H₂O) in soils dissolves easily creating voids which can be detrimental to the integrity of engineering structures. To mitigate this, it is important to determine the amount of gypsum present in soils, before construction is initiated.

In this study, three methods were employed in the determination of …

Multifaceted Environmental Enrichment In Industrial Fish Hatcheries: The Influence Of Enriched Rearing On The In-Situ Behaviour And Post-Stocking Success Of Juvenile Atlantic Salmon (Salmo Salar), Justine Elizabeth Mcandrews

Electronic Theses and Dissertations

Hatchery fish reared and stocked to sustain or restore wild populations often perform poorly in novel environments compared to their wild counterparts. To combat maladaptive hatchery-acquired traits environmental enrichment is an emerging tool used to provide ‘life skills training’ to hatchery fish prior to release. Through the application of simple yet multifaceted enrichment protocols in an industrial fish hatchery, this thesis aimed to demonstrate how enrichment could be applied to improve the ecological viability of stocked fish. At a provincially-run fish hatchery, a subgroup of juvenile Atlantic salmon (Salmo salar) were subject to 10 weeks of environmental enrichment …

The Effects Of Prescribed Burning On Soil Water Infiltration Rates And Other Select Soil Physical And Chemical Properties In East Texas, Cassady Pennington Dunson, Brian P. Oswald, Kenneth Farrish, Tyson Hart

Electronic Theses and Dissertations

This study focused on whether prescribed burning affects soil physical and chemical properties, especially water infiltration, in Western Gulf Coast forests. Soil water infiltration rates were measured 1) pre-burn (before the fire), 2) post-burn (one month after the fire), and 3) at vegetation green-up (three months after the fire). Soil samples were also collected to determine the effects of prescribed burning on soil pH, bulk density, particle density, pore space, soil strength, O-horizon weight and depth (organic matter), water stable aggregates, and soil fertility. This project was conducted on two different burn intervals. The National Forests and Grasslands of Texas …

Revegetating Salt-Impacted Soils In The Northern Great Plains, Abigail P. Blanchard

Electronic Theses and Dissertations

In the northern Great Plains (NGP), an estimated 10.6 million hectares of land are affected by naturally occurring salt-impacted soil. Naturally occurring salt impaction results when rainfall causes salts in parent material to move upward through the soil profile and remain in the root zone causing osmotic and ionic stress, negatively affecting seed imbibition, germination, and plant growth. Common methods to remediate saltimpacted soils were developed in the irrigated soils of the Southwestern U.S., are ineffective in the non-irrigated soils of the NGP, and can exacerbate the problem. Therefore, new methods to remediate salt-impacted soil in the NGP are needed. …

The Effects Of Saline Soil On Microbiome And The Isolation Of Root-Associated Microbes To Relieve Salinity Stress, Duncan Jakubowski

Electronic Theses and Dissertations

Increasing levels of salinity in once-viable lands for crop production is a serious and growing problem in the Northern Great Plains. The objectives of this study were to determine the effects of saline soil on the microbial composition of plant roots and bulk soil, to measure metabolic changes in plant roots from saline soil, to determine the viability of root-associated microbes as inoculants to increase stress tolerance in plants, as well as determine the impact of saline soil on nitrogen cycling genes linked to greenhouse gas production. This study hypothesizes that high soil salinity levels have a significant impact on …

Evaluating Canola Genotypes For Growth And Yield Under Different Environmental Conditions In South Dakota, Unius Arinaitwe

Electronic Theses and Dissertations

Canola (Brassica napus L) and carinata (Brassica carinata A. Braun) are potential oilseed crops for diversifying cropping systems and expanding into marginal lands impacted by saline and sodic soils in South Dakota (SD). However, genotypes that are high yielding, with high agronomic adaptability and stability over diverse environments, and salt tolerant have not been selected. One field experiment was conducted at two environments (Brookings - eastern SD and Pierre - western SD) from 2019 to 2020 to evaluate genotypes for growth and yield stability. Three greenhouse experiments were conducted to evaluate genotypes for salt tolerance in …