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Full-Text Articles in Physical Sciences and Mathematics

Accuracy Assessment Of Measuring Linear And Areal Features In Aerial Imagery, I-Kuai Hung, David L. Kulhavy, Daniel R. Unger, Reid A. Viegut, Yanli Zhang, Nicholas C. Schiwitz Dec 2023

Accuracy Assessment Of Measuring Linear And Areal Features In Aerial Imagery, I-Kuai Hung, David L. Kulhavy, Daniel R. Unger, Reid A. Viegut, Yanli Zhang, Nicholas C. Schiwitz

International Journal of Geospatial and Environmental Research

As part of natural resource education in the Arthur Temple College of Forestry and Agriculture at Stephen F. Austin State University (SFASU), students were instructed to take areal and linear measurements of grounds remotely using available platforms including aerial orthomosaic derived from UAS (unmanned aerial system) acquired imagery, Google Earth Pro, and Pictometry. The onscreen measurement was conducted at five different map scales, 1/1000, 1/2000, 1/3000, 1/4000, and 1/5000. Accuracy of the measurements was assessed by comparing the onscreen measurements to ground truth data verified with a measuring tape. Results show that measurements based on the UAS were more accurate …


Nutrient Dynamics Of Freshwater Estuarine Sediments Disturbed By Dredging, Ryan Allan John Roekle Aug 2023

Nutrient Dynamics Of Freshwater Estuarine Sediments Disturbed By Dredging, Ryan Allan John Roekle

Theses and Dissertations

This study examined the nutrient environment of sediments in the Milwaukee River estuary and the dynamics of those nutrients during simulated disturbance experiments within the context of large-scale dredging remediation. Surface sediments were collected from throughout the Milwaukee estuary (including river, harbor, and nearshore stations) by PONAR, centrifuged to separate porewater (interstitial water) from solid material, and filtered to further isolate and stabilize dissolved material. Porewaters were analyzed for dissolved nutrients including ammoniacal nitrogen (AN), nitrate, nitrite, and soluble reactive phosphorus (SRP). Surface sediment porewaters within the estuary were often highly enriched in AN and SRP, which were often 10-2000x …


Benthic Algal And Macroinvertebrate Response To The Removal Of Dreissenid Mussels In The Nearshore Zone Of Lake Michigan, Tyler Alexander Kunze Aug 2023

Benthic Algal And Macroinvertebrate Response To The Removal Of Dreissenid Mussels In The Nearshore Zone Of Lake Michigan, Tyler Alexander Kunze

Theses and Dissertations

Dreissenid mussels (Dreissena polymorpha and Dreissena rostriformis bugensis) have changed the fundamental community structure and biogeochemical processes of the Lake Michigan nearshore zone. There is evidence that dreissenids promote the nuisance growth of benthic algae, especially Cladophora sp. In addition, benthic macroinvertebrates have benefitted from the presence of dreissenid mussels due to the increased structural complexity along with greater nutrient availability in the benthos. These effects of the dreissenid mussel invasion are well documented; however, little is known about how these systems respond to the removal of dreissenid mussels from a once-populated area. Therefore, it is important to further our …


Comparing Drone2map Versus Pix4dmapper When Creating Orthophoto Mosaics Over Homogeneous Land Features, Victoria Williams, Daniel R. Unger, David Kulhavy, I-Kuai Hung, Yanli Zhang Jul 2023

Comparing Drone2map Versus Pix4dmapper When Creating Orthophoto Mosaics Over Homogeneous Land Features, Victoria Williams, Daniel R. Unger, David Kulhavy, I-Kuai Hung, Yanli Zhang

International Journal of Geospatial and Environmental Research

This study evaluated two popular software packages currently used within the natural resources profession to create orthophoto mosaics: Drone2Map and Pix4Dmapper. Of particular concern was how effective these two software packages would perform in creating orthophoto mosaics over a city park in East Texas consisting of forest, open grass, and urban concrete surrounding a lake. Two drone flights over the city park were conducted. One flight was at 76 meters (250 feet) above ground with a single pass configuration. The other flight was at 122 meters (400 feet) above ground with a double pass configuration. Upon the completion of each …


The Role Of Energy Storage In The Transition Toward A Carbon-Neutral Economy, Siyu Feng May 2023

The Role Of Energy Storage In The Transition Toward A Carbon-Neutral Economy, Siyu Feng

Theses and Dissertations

Energy transitions to less-carbon intense technologies, such as wind and solar energy, in the electricity, sector are crucial to realizing international climate goals because the electricity sector has been one of the main global carbon emitter for decades, and environmental plans in most countries involve electrifying heavily polluting industries with clean electricity generation. The intermittency problem of renewable energy has been the main stumbling block on the path, and energy storage is now referred to as the key in these transitions because it can boost renewable energy use while also improving the efficiency of conventional power plants (Hall and Bain, …


Aestheticization As A Type Of Erasure: An Ecocritical Examination Of Three Etchings From James Mcneill Whistler's 'Thames Set' (1859-1871), Sydney Ion May 2023

Aestheticization As A Type Of Erasure: An Ecocritical Examination Of Three Etchings From James Mcneill Whistler's 'Thames Set' (1859-1871), Sydney Ion

Theses and Dissertations

This thesis explores “A Series of Sixteen Etchings of Scenes on the Thames” (1859-1871), Thames Set, by James Abbott McNeill Whistler (1834-1903), a group of etchings that negotiates the effects of the “Great Stink” on the Thames riverbank and its people. I argue that the series exhibits a strange paradox: the intentional exclusion of accurate environmental elements and sensorial details to achieve a romanticized nostalgic framework that serves Whistler’s aesthetic ideals. This aestheticization of the environmental crisis is the foundation from which Whistler’s modernization grew. Recent research has understood the Thames Set as evidence of Whistler’s involvement in depicting lower-class …


Elucidating Unique Sources And Persistent Hydrologic Pathways Of Chloride To Perennial Freshwater Streams: Root River Analog In A Cold-Weather Environment, Leah Elizabeth Dechant May 2023

Elucidating Unique Sources And Persistent Hydrologic Pathways Of Chloride To Perennial Freshwater Streams: Root River Analog In A Cold-Weather Environment, Leah Elizabeth Dechant

Theses and Dissertations

Chloride in freshwater streams is increasing in concentration, persisting throughout the year, and contributing to the salinization of water resources. The primary source and pathway of chloride in cold-weather environments are thought to be road salt and runoff. However, mounting evidence displays that other sources and pathways of chloride play an important role yet studies to elucidate them at a high resolution, both temporally and spatially, and across diverse land use are lacking. In this study, chloride was quantified continuously for an urban and rural stream year-round in a watershed thought to be heavily impacted by road salt. Bivariate mixing …


Special Thanks To Reviewers 2021-2022, Woonsup Choi Mar 2023

Special Thanks To Reviewers 2021-2022, Woonsup Choi

International Journal of Geospatial and Environmental Research

Sincere thanks are extended to the individuals who reviewed manuscripts for International Journal of Geospatial and Environmental Research during the period from 1 January 2021 to 31 December 2022.