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Full-Text Articles in Physical Sciences and Mathematics

Transport And Fate Of Phosphorus In The Nearshore Zone Of Lake Michigan, Nathan Van Ee Dec 2021

Transport And Fate Of Phosphorus In The Nearshore Zone Of Lake Michigan, Nathan Van Ee

Theses and Dissertations

Bioavailable phosphorus loads exported to Lake Michigan from the Milwaukee and Sheboygan River Watersheds appear to have increased in the last 40 years despite meeting total phosphorus (TP) loading goals set by the Great Lakes Water Quality Agreement (GLWQA).Overall, bioavailability of P delivered from the Milwaukee and Sheboygan Rivers was highest during the warmer months, which coincides with the nearshore nuisance algae growth season. However, first order loss rates of SRP calculated during baseflow recession were also greatest during the summer, suggesting that increased river residence time during the summer could reduce export of bioavailable P. Observations of phosphorus partitioning …


Characterizing Clustering Models Of High-Dimensional Remotely Sensed Data Using Subsampled Field-Subfield Spatial Cross-Validated Random Forests, Andrew B. Whetten Nov 2021

Characterizing Clustering Models Of High-Dimensional Remotely Sensed Data Using Subsampled Field-Subfield Spatial Cross-Validated Random Forests, Andrew B. Whetten

International Journal of Geospatial and Environmental Research

Clustering models are regularly used to construct meaningful groups of observations within complex datasets, and they are an exceptional tool for spatial exploratory analysis. The clusters detected in a recent spatio-temporal cluster analysis of leaf area index (LAI) in the Columbia River Basin (CRB) require further investigation since they are only derived using a single greenness metric. It is of great interest to further understand how greening indices can be used to determine separation of sites across an array of remotely sensed environmental attributes. In this prior work, there are highly localized minority clusters that were detected to be most …


The Spatial Patterns Of Pluvial Flood Risk, Blue-Green Infrastructure, And Social Vulnerability: A Case Study From Two Alaskan Cities, Arun K. Pallathadka, Heejun Chang, Idowu Ajibade Oct 2021

The Spatial Patterns Of Pluvial Flood Risk, Blue-Green Infrastructure, And Social Vulnerability: A Case Study From Two Alaskan Cities, Arun K. Pallathadka, Heejun Chang, Idowu Ajibade

International Journal of Geospatial and Environmental Research

Flooding is a serious form of natural hazard in Alaska, USA. Two of Alaska’s biggest cities, Anchorage and Fairbanks, have experienced flooding of varying magnitude since the cities were first settled in the early 20th century. Although flood mitigation measures such as blue-green infrastructure (BGI) are rising in prominence, the spatial relationship of BGI, urban pluvial flood (UPF) zone, and social vulnerability remains understudied. This study delineates the UPF zone of Anchorage and Fairbanks using the Blue Spot modeling and correlates it with the distribution of BGI at Census Block Group (CBG) scale, focusing on underlying social vulnerability using a …


Measuring Spatio-Temporal Responses To Hurricane Matthew Employing Twitgis, Seungil Yum Sep 2021

Measuring Spatio-Temporal Responses To Hurricane Matthew Employing Twitgis, Seungil Yum

International Journal of Geospatial and Environmental Research

This study explores spatio-temporal responses to Hurricane Matthew across the US states by analyzing Twitter data. This study finds that people in different states and periods respond differently to Hurricane Matthew. For instance, people in the Midwest and Northeast regions show a high proportion of tweets in the pre-hurricane period. Those in the Southeast region demonstrate a high proportion of those in the hurricane period, and those in the West region show a high proportion of those in the post-hurricane period. This study also finds that people increase long distance trips (over 100 km) and decrease short distance trips (within …


Transcriptomics And Toxcast Data Identify Bioeffects In Zebrafish Embryos Exposed To Chemical Mixtures In An Effluent-Dominated Stream, Emma Meade Aug 2021

Transcriptomics And Toxcast Data Identify Bioeffects In Zebrafish Embryos Exposed To Chemical Mixtures In An Effluent-Dominated Stream, Emma Meade

Theses and Dissertations

Wastewater treatment plant (WWTP) effluent-dominated streams provide critical habitat for aquatic organisms but also continually expose them to complex mixtures of pharmaceuticals and other contaminants of emerging concern (CECs) that can potentially impair growth, behavior, and reproduction. Limited toxicity data on the adverse biological impacts of in vivo exposure to these mixtures make it difficult to assess risk for aquatic organisms, particularly with respect to pharmaceuticals whose designed bioactivity often extends beyond conventionally monitored biological pathways. To address this knowledge gap, the goal of this thesis was to identify biomarkers of exposure to complex CEC mixtures relevant to specific chemicals …


Selection And Demography Drive Range-Wide Patterns Of Mhc Variation In Mule Deer (Odocoileus Hemionus), Rachel M. Cook Aug 2021

Selection And Demography Drive Range-Wide Patterns Of Mhc Variation In Mule Deer (Odocoileus Hemionus), Rachel M. Cook

Theses and Dissertations

Variation at functional genes involved in immune response is of increasing concern as wildlife diseases continue to emerge and threaten populations. The amount of standing genetic variation in a population is directly associated with its potential for rapid adaptation to novel environments. For genes in the major histocompatibility complex (MHC), which are crucial in activating the immune response and which have extremely high levels of polymorphism, the genetic variation has been shown to be influenced by both parasite-mediated selection and historical population demography. To better understand the relative roles of parasite-mediated selection and demography on MHC evolution in large populations, …


Geospatial Technology In Sustainable Cities And Communities: Introduction To The Special Issue, Siti Aekbal Salleh, Zulkiflee Abd Latif, Nazri Che Dom Jul 2021

Geospatial Technology In Sustainable Cities And Communities: Introduction To The Special Issue, Siti Aekbal Salleh, Zulkiflee Abd Latif, Nazri Che Dom

International Journal of Geospatial and Environmental Research

This special issue aims to demonstrate how we could leverage geospatial technology for sustainable cities and communities. Contributions on a wide range of geospatial technologies (e.g., GIS, remote sensing, spatial statistics, photogrammetry, and geomatics) as well as issues addressing better cities and communities for a sustainable future are encouraged. This issue contains selected papers from the 7th International Conference on Geomatics and Geospatial Technology (GGT) 2021, which took place in Kuala Lumpur, Malaysia, on 24th March 2021. The five articles selected for this special issue demonstrate how geospatial technology can be used to create more sustainable cities and communities. The …


Geological Lineament Assessment From Passive And Active Remote Sensing Imageries, Ainyyafiatty Arifin, Nor A. Adnan Jul 2021

Geological Lineament Assessment From Passive And Active Remote Sensing Imageries, Ainyyafiatty Arifin, Nor A. Adnan

International Journal of Geospatial and Environmental Research

Lineament is any extensive linear feature on the Earth’s surface that can be identified when there is a change in the topographical data. The advancement of technologies in remote sensing and Geographical Information Sciences (GIS) lead to the various studies and methods in mapping lineaments due to the availability of data from small to large scale areas. Lineament can be extracted from remote sensing data either with manual, semi-automatic or automatic image processing techniques that incorporate in numerous remote sensing and GIS software. Manually digitizing or tracing the aerial photograph is a subjective method as the lineament will be interpreted …


A Comparative Study Of Delineated Watersheds Using Aster And Srtm In Johor, Malaysia, Nafisah Khalid, Maisarah Abdul Halim, Siti Nur A’Tirah Shahimi Jun 2021

A Comparative Study Of Delineated Watersheds Using Aster And Srtm In Johor, Malaysia, Nafisah Khalid, Maisarah Abdul Halim, Siti Nur A’Tirah Shahimi

International Journal of Geospatial and Environmental Research

The availability of watershed delineation that has been generated from DEM data is difficult to obtain and the accessibility of DEM data which are unrestricted and precise are hard to obtain in Malaysia. The aim of this study is to examine the accuracy of watershed delineation between Digital Elevation Model (DEM) from ASTER and SRTM in Johor State Malaysia. In this study, free online data sources from USGS website are used to delineate watershed from ASTER and SRTM satellite imageries. The hydrological modelling tool namely ArcSWAT is utilized to delineate watersheds for both DEM datasets. Both DEM data that had …


Travel Time Patterns Of Students With Special Needs To Special Education Integrated Program-Based Schools In Johor Bahru, Malaysia: An Initial Finding, Nurul Hawani Idris, Nur Afiqah Ahmad Bakhtiar, Mohamad Hafis Izran Ishak May 2021

Travel Time Patterns Of Students With Special Needs To Special Education Integrated Program-Based Schools In Johor Bahru, Malaysia: An Initial Finding, Nurul Hawani Idris, Nur Afiqah Ahmad Bakhtiar, Mohamad Hafis Izran Ishak

International Journal of Geospatial and Environmental Research

Education for all has been a global priority to ensure that all students have equal access to high-quality education regardless of disability or minority status. In Malaysia, the special education integrated programme (SEIP) is designed to close the inequality gap by integrating special education into existing government and vernacular schools. Numerous studies examine the travel patterns of regular students to school, resulting in a dearth of research on the travel patterns of special needs students to formal school. Thus, this paper uses spatial analysis to demonstrate the travel patterns of students with special needs to SEIP schools. This paper demonstrated …


Geospatial Clustering And Hot Spot Detection Of Covid-19 Incidence In 2020: A Global Analysis, Munazza Fatima, Sana Arshad, Ibtisam Butt, Saba Arshad May 2021

Geospatial Clustering And Hot Spot Detection Of Covid-19 Incidence In 2020: A Global Analysis, Munazza Fatima, Sana Arshad, Ibtisam Butt, Saba Arshad

International Journal of Geospatial and Environmental Research

Emergence and spread of Covid-19 initiated diversified researches based on spatial analysis in visualization, exploration, and modelling of this infection. This short communication is an attempt to comprehend the geographic distribution and spatial clustering of Covid-19 in year 2020. Main objective is to spatially analyze Covid-19 incidence rates, identification of hotspots and clusters outliers at global level. Monthly data of reported cases were taken from World Health Organization dashboard and situation reports. Incidence rate was calculated for each country for each month. Spatial autocorrelation techniques of Global Moran are I and Anselian Local Moran’s I were used to examine the …


The Flow Less Traveled: Documenting Independent Original Research On Fluid Flow Interactions In The Laurentian Great Lakes And Immediate Surroundings, Thomas F. Hansen May 2021

The Flow Less Traveled: Documenting Independent Original Research On Fluid Flow Interactions In The Laurentian Great Lakes And Immediate Surroundings, Thomas F. Hansen

Theses and Dissertations

This work is a compilation of several research projects undertaken by the author. Each research effort identifies a problem that has been addressed traditionally using methods that are significantly costly, to such an extent that, in general, funding, convenience, and practicality are primary limiting factors to their effective implementation. In each case, the author has been able to either build upon existing, less expensive alternatives, or even invent novel approaches. The fundamental recurring research question is, can creative, even novel, computational approaches make more efficient use of resources to interpret or present data in such a way as to make …


Molecular Weight Distributions And Size-Dependent Composition Of Dissolved Organic Matter In The Aquatic Continuum, Hui Lin May 2021

Molecular Weight Distributions And Size-Dependent Composition Of Dissolved Organic Matter In The Aquatic Continuum, Hui Lin

Theses and Dissertations

Dissolved organic matter (DOM) in aquatic environments is one of the most important carbon reservoirs in global carbon cycling. The molecular weight of DOM is strongly related to a great number of biogeochemical reactions, influencing ecological functions and the fate of bioactive elements in aquatic ecosystems. A new technique coupling flow field-flow fractionation with fluorescence excitation-emission matrix (EEM) and parallel factor (PARAFAC) analysis was developed to elucidate the variations in DOM composition and optical properties with molecular weight in the individual samples and their changes along the aquatic continuum. Based on the novel coupling technique, variations in DOM characteristics were …


Health Goals For Perfluorinated Alkyl Substances (Pfas): A Review Of Branched Isomers, The Role Of Industrial Sources, And The Implications Of Pfas In Biosolids On End-Of-Life Disposal Methods, Katarina Schulz May 2021

Health Goals For Perfluorinated Alkyl Substances (Pfas): A Review Of Branched Isomers, The Role Of Industrial Sources, And The Implications Of Pfas In Biosolids On End-Of-Life Disposal Methods, Katarina Schulz

Theses and Dissertations

Per- and polyfluorinated alkyl substances, or PFAS, have been used for over half a century, but have become an emerging contaminant of significant concern due to their newly found widespread occurrence and recalcitrance in the environment, their tendency to bioaccumulate, and the health effects now associated with a very low level of exposure. Many gaps in knowledge remain about the fate of these chemicals in the environment and the extent of their impacts on biota. This thesis aims to fill some of the recognized gaps in knowledge: differences between linear and branched isomers of PFAS, predicting the presence of PFAS …


An Internatural Communication Study Of Identity Within Nonprofit Animal Shelters, Samentha Emily Sepúlveda May 2021

An Internatural Communication Study Of Identity Within Nonprofit Animal Shelters, Samentha Emily Sepúlveda

Theses and Dissertations

In a two-part study of this dissertation project, I relied on qualitative research methods to examine the stories of animal shelter employees and volunteers—stories about animal shelters, animal sheltering, and shelter animals—to analyze communication processes that shape staff-identity, organizational-identity, and organizational identification. This project was guided by the communicative constitution of organizations (CCO) approach, which frames communication as not simply something that happens within an organization, but rather argues organization happens in communication. Furthermore, contributing to internatural communication research, this project explored identity and identification from a “more-than human” perspective. Relating CCO and internatural communication to research in this dissertation …


Application Of Deep Learning For Imaging-Based Stream Gaging, Ryan Lee Vanden Boomen May 2021

Application Of Deep Learning For Imaging-Based Stream Gaging, Ryan Lee Vanden Boomen

Theses and Dissertations

In the field of water resources management, one vital instrument utilized is the stream gage. Stream gages monitor and record flow and water height within some water body. The United States Geological Survey maintains a network of stream gages at many locations across the country. Many of these sites are also equipped with webcams monitoring the state of the water body at the moment of measurement. Previous studies have outlined methods to approximate stream gage data remotely with limitations such as the requirement of detailed depth information for each site. This study seeks to create a process for training a …


Bottom-Up Understanding Of Informal Settlements: Perspectives Of Urban Slum Dwellers In Nima, Ghana., Bernard Apeku May 2021

Bottom-Up Understanding Of Informal Settlements: Perspectives Of Urban Slum Dwellers In Nima, Ghana., Bernard Apeku

Theses and Dissertations

More than a quarter of the world’s population lives in informal settlements which house a rapidly growing proportion of the inhabitants of cities in sub-Saharan Africa, such as Accra, Ghana, and in the Global South more generally. However, scholars have shown that the urban planning and urban redevelopment strategies that affect these settlements are top-down in character with minimal resident participation. These prevailing planning and redevelopment strategies are based on the outsiders’ perceptions of informal neighborhoods, rendering them quite inefficient. Therefore, to develop workable policies and strategies that will improve the living condition of informal urban settlers, it is important …


Special Thanks To Reviewers 2020, Woonsup Choi Mar 2021

Special Thanks To Reviewers 2020, 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 of 1 January to 31 December 2020.