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Articles 1 - 30 of 72
Full-Text Articles in Social and Behavioral Sciences
Connectivity: Insights From The U.S. Long Term Ecological Research Network, David M. Iwaniec, Michael Gooseff, Katharine Suding, David Samuel Johnson, Daniel C. Reed, Debra Peters, Byron Adams, John E. Barrett, Brandon Bestelmeyer, Max C.N. Castorani, Elizabeth M. Cook, Melissa J. Davidson, Peter F. Groffman, Niall Hanan, Laura Huenneke, Pieter T.J. Johnson, Diane Mcknight, Robert J. Miller, Gregory Okin, Daniel Preston, Andrew Rassweiler, Chris Ray, Osvaldo Sala, Robert L. Schooley, Timothy Seastedt, Marko Spasojevic, Enrique R. Vivoni
Connectivity: Insights From The U.S. Long Term Ecological Research Network, David M. Iwaniec, Michael Gooseff, Katharine Suding, David Samuel Johnson, Daniel C. Reed, Debra Peters, Byron Adams, John E. Barrett, Brandon Bestelmeyer, Max C.N. Castorani, Elizabeth M. Cook, Melissa J. Davidson, Peter F. Groffman, Niall Hanan, Laura Huenneke, Pieter T.J. Johnson, Diane Mcknight, Robert J. Miller, Gregory Okin, Daniel Preston, Andrew Rassweiler, Chris Ray, Osvaldo Sala, Robert L. Schooley, Timothy Seastedt, Marko Spasojevic, Enrique R. Vivoni
Sustainable Futures Lab Publications
Ecosystems across the United States are changing in complex and surprising ways. Ongoing demand for critical ecosystem services requires an understanding of the populations and communities in these ecosystems in the future. This paper represents a synthesis effort of the U.S. National Science Foundation-funded Long-Term Ecological Research (LTER) network addressing the core research area of “populations and communities.” The objective of this effort was to show the importance of long-term data collection and experiments for addressing the hardest questions in scientific ecology that have significant implications for environmental policy and management. Each LTER site developed at least one compelling case …
What Can We Learn From X‐Ray Fluorescence Core Scanning Data? A Paleomonsoon Case Study, Daniel Gebregiorgis, Liviu Giosan, Edmund Hathorne, Pallavi Anand, Katrina Nilsson-Kerr, Anna Plaß, Andreas Lückge, Steven Clemens, Martin Frank
What Can We Learn From X‐Ray Fluorescence Core Scanning Data? A Paleomonsoon Case Study, Daniel Gebregiorgis, Liviu Giosan, Edmund Hathorne, Pallavi Anand, Katrina Nilsson-Kerr, Anna Plaß, Andreas Lückge, Steven Clemens, Martin Frank
Geosciences Faculty Publications
X‐ray fluorescence (XRF) core scanning of marine and lake sediments has been extensively used to study changes in past environmental and climatic processes over a range of timescales. The interpretation of XRF‐derived element ratios in paleoclimatic and paleoceanographic studies primarily considers differences in the relative abundances of particular elements. Here we present new XRF core scanning data from two long sediment cores in the Andaman Sea in the northern Indian Ocean and show that sea level related processes influence terrigenous inputs based proxies such as Ti/Ca, Fe/Ca, and elemental concentrations of the transition metals (e.g., Mn). Zr/Rb ratios are mainly …
Oxygen Isotopes In Authigenic Clay Minerals: Toward Building A Reliable Salinity Proxy, Daniel Gebregiorgis, Daniel M. Deocampo, Fred Longstaffe, A. Simpson, Gail M. Ashley, Emily Beverly, Jeremy Delaney, Javier Cuadros
Oxygen Isotopes In Authigenic Clay Minerals: Toward Building A Reliable Salinity Proxy, Daniel Gebregiorgis, Daniel M. Deocampo, Fred Longstaffe, A. Simpson, Gail M. Ashley, Emily Beverly, Jeremy Delaney, Javier Cuadros
Geosciences Faculty Publications
Most clay minerals in sedimentary environments have traditionally been considered to be of detrital origin, but under certain conditions, authigenic clay minerals can form at low temperature through the transformation of precursor clays or as direct precipitates from lake water. Such clay minerals can hold important information about the prevailing climatic conditions during the time of deposition. We present the first quantitative reconstruction of salinity in paleolake Olduvai based on the oxygen‐isotope composition of authigenic clay minerals. We provide a framework illustrating that the isotopic signature of authigenic lacustrine clay minerals is related to the isotopic composition of paleo‐waters, and …
What Causes People To Change Their Opinion About Climate Change?, Risa Palm, Gregory B. Lewis, Bo Feng
What Causes People To Change Their Opinion About Climate Change?, Risa Palm, Gregory B. Lewis, Bo Feng
Geosciences Faculty Publications
After a decade of steady growth in the acceptance of the existence of climate change and its anthropogenic causes, opinions have polarized, with almost one-third of Americans, mostly Republicans, denying that the climate is changing or that human activity is responsible. What causes Americans to change their minds on this issue? Using a large panel data set, we examined the impacts of direct experience with weather anomalies, ideology, relative prioritization of environmental conservation in comparison to economic development, and motivated reasoning that adjusts individual opinion to align with others who share one’s party identification. A generalized ordered logit model confirmed …
Karst Topography And Sacred Places: A Comprehensive Approach To Understanding The Maya Landscape With Applied Gis, John Edward Sabin 6946816
Karst Topography And Sacred Places: A Comprehensive Approach To Understanding The Maya Landscape With Applied Gis, John Edward Sabin 6946816
Georgia State Undergraduate Research Conference
No abstract provided.
Marine Transgression And Vegetation Environments In St. Catherines Island, Georgia, Rachel Luu
Marine Transgression And Vegetation Environments In St. Catherines Island, Georgia, Rachel Luu
Georgia State Undergraduate Research Conference
No abstract provided.
Spatial Distribution Of Lead In Sacramento, California, Usa, Michael J. Solt, Daniel M. Deocampo, Michelle Norris
Spatial Distribution Of Lead In Sacramento, California, Usa, Michael J. Solt, Daniel M. Deocampo, Michelle Norris
Geosciences Faculty Publications
Chronic exposure to lead remains a health concern in many urban areas; Sacramento, California is one example, with state surveillance data showing nearly 3% of screened children reported with blood lead levels over 4.5 μg/dL in 2009. To investigate the environmental exposure, 91 soil samples were collected and analyzed by ICP-AES and ICP-MS for 14 elements. An additional 28 samples were collected from areas of focus and analyzed by hand-held X-ray fluorescence spectrometry for Pb and Zn. Analysis of the metals data revealed non-normal distributions and positive skewness, consistent with anthropogenic input. In addition, high correlation coefficients (≥0.75) of metal …
Mapping Marine Debris Through The Coastal Communities Of Belize: Plastics, Pollution, And People, Paulita A. Bennett-Martin
Mapping Marine Debris Through The Coastal Communities Of Belize: Plastics, Pollution, And People, Paulita A. Bennett-Martin
Georgia State Undergraduate Research Conference
No abstract provided.
Intergenerational Mobility And Urban Spatial Structure, Sebastian Quintero
Intergenerational Mobility And Urban Spatial Structure, Sebastian Quintero
Georgia State Undergraduate Research Conference
No abstract provided.
Quantitative Community Geography: A Preliminary Evaluation Of Nitrogen Dioxide Levels And Possible Solutions To Exposure Rates In Npu-V, Atlanta, Ga, Alyssa M. Combs, Maria C. Martinez, Kumar K. Amarnath, Hannah Kaplan, Mary Winsor, Rebecca A. Pickering
Quantitative Community Geography: A Preliminary Evaluation Of Nitrogen Dioxide Levels And Possible Solutions To Exposure Rates In Npu-V, Atlanta, Ga, Alyssa M. Combs, Maria C. Martinez, Kumar K. Amarnath, Hannah Kaplan, Mary Winsor, Rebecca A. Pickering
Georgia State Undergraduate Research Conference
No abstract provided.
Developing A Gis Methodology For Mapping Elements Of Urban Greenspace, Paulita A. Bennett-Martin
Developing A Gis Methodology For Mapping Elements Of Urban Greenspace, Paulita A. Bennett-Martin
Georgia State Undergraduate Research Conference
No abstract provided.
Road Dust Lead (Pb) In Two Neighborhoods Of Urban Atlanta, (Ga, Usa), Daniel Deocampo Ph.D, Phillip Jack Reed, Alexander P. Kalenuik
Road Dust Lead (Pb) In Two Neighborhoods Of Urban Atlanta, (Ga, Usa), Daniel Deocampo Ph.D, Phillip Jack Reed, Alexander P. Kalenuik
Geosciences Faculty Publications
Road dust continues to be a major potential reservoir of Pb in the urban environment, and an important potential component of child Pb exposure. This study presents ICP-AES analyses of metals in 72 samples of road dust (<250 μm) collected in the urban core of Atlanta, Georgia. In the Downtown area, median Pb concentrations are ~63 mg/kg Pb, with high values of 278 mg/kg. For comparison, median Pb values in a nearby residential neighborhood (also in the urban core) were ~93 mg/kg, with a high of 972 mg/kg. Geospatial variability is high, with significant variation observed over tens to hundreds of meters. Spearman Rank Correlation tests suggest that Pb and other metals (Cu, Ni, V, Zn) are associated with iron and manganese oxide phases in the residential area, as reported in other cities. However, Pb in the Downtown area is not correlated with the others, suggesting a difference in source or transport history. Given these complexities and the expected differences between road dust and soil Pb, future efforts to assess exposure risk should therefore be based on spatially distributed sampling at very high spatial resolution.
Whole-Rock Lead-Lead Systematics And Major Element Analyses On The 1.85 Ga. Flin Flon Paleosol, Manitoba, Canada: Implications For Uranium Mobility., Federico Arturo Valencia
Whole-Rock Lead-Lead Systematics And Major Element Analyses On The 1.85 Ga. Flin Flon Paleosol, Manitoba, Canada: Implications For Uranium Mobility., Federico Arturo Valencia
Geosciences Theses
The 1.85 Ga Flin Flon paleosol located in Flin Flon, Manitoba, Canada, is studied with the purpose of determining the timing and geochemical trend of uranium migration. Radiometric minimum ages of sediments and paleosols indicates the presence of a post-depositional event, these ages are bracketed by the Trans-Hudson orogeny event (2155–1750 Ma) which resulted in the alteration of κ(Th/U) and µ(U/Pb) ratios by exposing volcanics to the atmosphere and instigating the mobilization of U. The profile shows that the Missi sediments lost Uby 84% average relative to corrected average upper crust value. The upper paleosol gained U by 11% and …
A Geochemical Analysis: Application Of A Chelating Agent On Potential Asr Reactive Aggregates, Jennifer N. Garcia
A Geochemical Analysis: Application Of A Chelating Agent On Potential Asr Reactive Aggregates, Jennifer N. Garcia
Geosciences Theses
Alkali Silica Reaction (ASR) is a deleterious, expansive reaction in concrete. Several ASTM methods test potential aggregates for ASR risk. One method uses NaOH digestion, followed by spectroscopic methods, to estimate the amount of reactive silica present in an aggregate. NaOH, however, can digest both crystalline (i.e. quartz) and non-crystalline (e.g. opal), or poorly crystalline silica, potentially yielding falsely high estimates of reactive silica. Studies in soil and plant sciences have used Tiron, an alkaline chelating agent (C6H4S2O8Na2), as a method of digesting opaline silica for spectroscopic analysis. Here we …
The Impact Of Local Source Sediments On Bed Texture In The Fall River, Rocky Mountain National Park, Usa, Jordan A. Clayton, Kristopher N. Eby
The Impact Of Local Source Sediments On Bed Texture In The Fall River, Rocky Mountain National Park, Usa, Jordan A. Clayton, Kristopher N. Eby
Geosciences Faculty Publications
The bed texture of a gravel-bed river is related to the size distribution and quantity of source sediments, the routing of sediment through the reach, and the distribution of flow velocity. A reach morphology that is consistent in depth with little lateral topographic variation will typically have a bed texture that is characterized by a fairly uniform grain size distribution. However, spatial variations in source sediments within a given watershed may impact the distribution of gravel-bed river sediments, even at the reach scale, such that two proximal reaches of the same river having the same general morphology can exhibit contrasting …
Assessment Of Watershed Model Simplification And Potential Application In Small Ungaged Watersheds: A Case Study Of Big Creek, Atlanta, Ga, Zoia A. Comarova Ms
Assessment Of Watershed Model Simplification And Potential Application In Small Ungaged Watersheds: A Case Study Of Big Creek, Atlanta, Ga, Zoia A. Comarova Ms
Geosciences Theses
Technological and methodological advances of the past few decades have provided hydrologists with advanced and increasingly complex hydrological models. These models improve our ability to simulate hydrological systems, but they also require a lot of detailed input data and, therefore, have a limited applicability in locations with poor data availability. From a case study of Big Creek watershed, a 186.4 km2 urbanizing watershed in Atlanta, GA, for which continuous flow data are available since 1960, this project investigates the relationship between model complexity, data availability and predictive performance in order to provide reliability factors for the use of reduced …
Stakeholders' Perceptions Of Risk For Gentrification In Atlanta's Pittsburgh Neighborhood, David C. Holmes
Stakeholders' Perceptions Of Risk For Gentrification In Atlanta's Pittsburgh Neighborhood, David C. Holmes
Geosciences Theses
The 2008-2010 foreclosure crisis and the Beltline project present two significant forces shaping neighborhoods throughout Atlanta. Both the high foreclosure rates and the promise of public and private investment create conditions for the displacement of existing residents and for the gentrification of the southwest Atlanta neighborhood of Pittsburgh in particular. Through qualitative analysis, including interviews with residents, community leaders, and government officials, the development of overlay analysis maps of Pittsburgh, as well as studying the various stakeholders' perception of risk for gentrification in Pittsburgh, this research examines how and why these stakeholders' perception of the risk of gentrification in Pittsburgh …
Critical Thresholds For Sediment Mobility In An Urban Stream, Ross H. Martin
Critical Thresholds For Sediment Mobility In An Urban Stream, Ross H. Martin
Geosciences Theses
Bed load transport measurements were made in a small urban stream in Decatur, GA, from which thresholds for motion were calculated using methodologies from the published literature. These methodologies are discussed in terms of their limitations and assumptions. Mobility frequencies were calculated for single grains of each grain size fraction to illustrate the transition from size selective transport to equal mobility. In general, urban streams behave differently than many gravel rivers in non-urban settings because of differences in the availability and character of sediment sources and altered flow hydrographs. This comparison allows for discussion about the way sediment is transported …
Spatiotemporal Analyses Of Child Pedestrian-Vehicle Incidents Occurring During School-Commuting Hours In Metro Atlanta From 2000 To 2007, Amy M. Moore
Geosciences Theses
From 2000 to 2007, the five core county area of Metropolitan Atlanta (Fulton, Dekalb, Clayton, Cobb and Gwinnett) experienced 1,871 incidents involving child pedestrians. Nearly one-third of these incidents occurred during school-commuting hours. This study examines the geospatial locations of these incidents, with regards to the location of all 647 public schools within the study area. A GIS is used to analyze the spatiotemporal arrangement of these incidents in order to find risk factors and patterns in the data. Aspects of the built environment are then considered in areas with higher frequencies of child pedestrian-vehicle incidents. A walkability assessment is …
Intensive Study Of Ambient Carbon Dioxide Variability In Urban Atlanta, Brian L. Vann Mr.
Intensive Study Of Ambient Carbon Dioxide Variability In Urban Atlanta, Brian L. Vann Mr.
Geosciences Theses
Urban areas contain multiple sources and sinks of carbon dioxide, yet spatial and temporal information explaining its variability, diurnal patterns, and effects from human activity are limited. The city of Atlanta, due to conflicting air masses, geographic location, and population growth, is as an excellent location to study carbon dioxide concentrations across its urban landscape. Mobile measurements of ambient CO2 concentrations were obtained at 1.5m above ground level along a transect in winter 2010 within the perimeter of Atlanta. Analyses of winter 2010 CO2 variability at GSU’s stationary CO2 monitor was also explored. The results showed that …
Mineralogy And Geochemistry Of The Bauxite Deposits (Cretaceous), Wilkinson County, Georgia., Adebayo O. Ayorinde
Mineralogy And Geochemistry Of The Bauxite Deposits (Cretaceous), Wilkinson County, Georgia., Adebayo O. Ayorinde
Geosciences Theses
Cretaceous bauxite deposits from Hall and Veneer mines, Wilkinson County, Georgia are composed of kaolinite, gibbsite, goethite, anatase, nordstrandite and bohemite. Quartz and micas are absent in the samples. The presence of boehmite and goethite are evidence of intense weathering forming the bauxite deposits. The extremely high values of the Chemical Index of Alteration (CIA) which is over 99, and the low values of the alkali metals and alkali earth metals, support an intense weathering origin for the bauxite deposit. There is evidence of deposition in the mines based on the presence of pisoids in the bauxite samples and the …
Particle Size, Critical Shear Stress, And Benthic Invertebrate Distribution And Abundance In A Gravel-Bed River Of The Southern Appalachians, Helen Mayoral
Geosciences Theses
To determine the relationship between the abundance and density of benthic invertebrates, and the critical shear stress of individual grain sizes, a reach along Smith Creek, was divided into ten 2m x 2m quadrants. Within each quadrant, five randomly selected clasts for each grain size ranging from 2.26 to 25.6 cm were cleaned for benthic invertebrates. Wolman pebble counts for each quadrant were also conducted and used to determine the critical Shields stress per grain size fraction from the model given by Wiberg and Smith (1987) that explicitly accounts for particle hiding/sheltering effects in mixed-bed rivers. Particle entrainment values were …
Labor Agency Beyond The Union: The Coalition Of Immokalee Workers And Faith-Based Community Organizations, Michael Husebo
Labor Agency Beyond The Union: The Coalition Of Immokalee Workers And Faith-Based Community Organizations, Michael Husebo
Geosciences Theses
Labor geographers have identified multiple strategies through which workers assert their demands in an era of global production networks. In this thesis I examine the strategic organizational actions of the Coalition of Immokalee Workers (CIW), a community-based organization representing immigrant farm-workers in southwestern Florida. Central to the successes of the CIW is its strategy to organize and embed its agency in civil society. Social actors have proved to be of vital importance as they enabled the CIW to position itself strategically in important locations of the production network to contest capitalist geographies more effectively. Using qualitative analysis of in-depth interviews …
The Effects Of High Density Septic Systems On Surface Water Quality In Gwinnett County, Georgia, John R. Anderson Ii
The Effects Of High Density Septic Systems On Surface Water Quality In Gwinnett County, Georgia, John R. Anderson Ii
Geosciences Theses
Gwinnett County, Georgia experienced rapid growth in the 1970’s without the infrastructure so septic systems were installed for residential homes. The number of septic systems grew to over 85,000 with a density of 487 septic systems per square mile. This study mapped the distribution of septic systems to determine regions of potential pathogen surface water. This study addressed what potential health risks do high density septic systems have on surface water quality and how can the history of Gwinnett County assist in future development in the Metropolitan Atlanta area? It was found that the density of septic systems has reduced …
K-Ar Age Values Of Bulk Soil Samples And Clay Fractions: Effects Of Acid Extraction And Implications For The Origin Of Micaceous Clay In Savannah River Site Soils, South Carolina, Usa, Thomas E. Naumann
Geosciences Theses
Understanding how natural Cs, Rb, and K have been redistributed in Savannah River Site (SRS) soils during pedogenesis is important to understanding how radiocesium released to the soils will behave over the long term. In this effort, it is important to distinguish K that has participated in mineral-water reactions from that still residing in primary silicate structures, particularly in the clay fraction. The impact of different degrees of acid extraction on K and radiogenic Ar in bulk soil and in clay from five SRS soil samples has been determined. Strong treatment (50% HNO3, three hours, 100°C) releases K from primary …
Mineralogical And Geochemical Indicators Of Subaerial Weathering In The Pozzolane Rosse Ignimbrite (Alban Hills Volcanic District, Italy), Jennifer M. Dickie
Mineralogical And Geochemical Indicators Of Subaerial Weathering In The Pozzolane Rosse Ignimbrite (Alban Hills Volcanic District, Italy), Jennifer M. Dickie
Geosciences Theses
The Pozzolane Rosse ignimbrite [PR] (457±4 ka) in the Alban Hills Volcanic District, Rome, Italy was exposed ~ 40 ka prior to a subsequent volcanic event which coverd it entirely. XRF, XRD, and clay separation results from PR samples from INGV and CA1 boreholes and Castel di Leva quarry show evidence of paleopedogenesis. All locations display loss of base cations, loss of K is consistent with XRD datat showing dissolution or alteration of leucite to analcime. Accumulation of Al and high L.O.I. support XRD evidence of 1:1 clay species at upper depth. Data suggest alteration extent can be determined by …
Censoring Maps In Google China? Visual Analysis Through Foucault't Power/Knowledge, Zhanar Karimbayeva
Censoring Maps In Google China? Visual Analysis Through Foucault't Power/Knowledge, Zhanar Karimbayeva
Geosciences Theses
This thesis explores aspects of map censorship in Google China through a theoretical framework based on Foucault’s power/knowledge. Comparing results of content analysis of maps in Google Ditu in Google China and Google Maps in Google Dot Com, the thesis analyzes the degree of censorship of maps in the Google geoweb. My findings are a higher density of labeling in Google Ditu in comparison with Google Maps, the absence of VGI in Google Ditu, the limitation of zoom level at Google Ditu, and the absence of Street View in China. This thesis suggests possible explanations to differences in map information …
Ontology And Knowledge Base Of Brittle Deformation Microstructures For The San Andreas Fault Observatory At Depth (Safod) Core Samples, Cynthia Marie Broda
Ontology And Knowledge Base Of Brittle Deformation Microstructures For The San Andreas Fault Observatory At Depth (Safod) Core Samples, Cynthia Marie Broda
Geosciences Theses
The quest to answer fundamental questions and solve complex problems is a principal tenet of Earth science. The pursuit of scientific knowledge has generated profuse research, resulting in a plethora of information-rich resources. This phenomenon offers great potential for scientific discovery. However, a deficiency in information connectivity and processing standards has become evident. This deficiency has resulted in a demand for tools to facilitate and process this upsurge in information. This ontology project is an answer to the demand for information processing tools. The primary purpose of this domain-specific ontology and knowledge base is to organize, connect, and correlate research …
Analysis Of Precipitates And Waters Associated With An Alkaline Leachate, Gulf State Steel Property, Gadsden, Alabama: A Reconnaissance Study, Craig Vantrees
Analysis Of Precipitates And Waters Associated With An Alkaline Leachate, Gulf State Steel Property, Gadsden, Alabama: A Reconnaissance Study, Craig Vantrees
Geosciences Theses
Calcite stalactites ranging in length from several inches to a foot long are found forming on the southeastern slag pile at the former Gadsden Steel Mill of the Gulf States Steel Corporation. Analyses of samples collected per EISOPQAM guidelines include the following: petrographic, conductivity, pH, XRD, XRF, TDS, and major cations and anions. Preliminary field pH and conductivity measurements indicate that waters near the slag pile have a pH ranging from 11-12 and a conductivity ranging from 1115-6300 μS/ cm. Titration data indicate that the maximum pH value is 12.5. These calcite stalactites and stream coatings result from the dissolution …
John Borchert’S “American Metropolitan Evolution”, Risa Palm
John Borchert’S “American Metropolitan Evolution”, Risa Palm
Geosciences Faculty Publications
The article presents comments on the article "American Metropolitan Evolution," originally published in 1967 by the urban geographer John Borchert. Details are given overviewing the thesis and research of the paper, focusing on its discussion of the organizational structure of the four "epochs" of urban development in U.S. history. Discussion is offered explaining the significance of the 1967 paper. The author also highlights the influence which the article had on his own research and of the field at large over 40 years.