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2014

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Articles 781 - 810 of 1044

Full-Text Articles in Earth Sciences

Combined Effects Of Phosphorus Nutrition And Elevated Carbon Dioxide Concentration On Chlorophyll Fluorescence, Photosynthesis, And Nutrient Efficiency Of Cotton, Shardendu K. Singh, Vangimalla R. Reddy Jan 2014

Combined Effects Of Phosphorus Nutrition And Elevated Carbon Dioxide Concentration On Chlorophyll Fluorescence, Photosynthesis, And Nutrient Efficiency Of Cotton, Shardendu K. Singh, Vangimalla R. Reddy

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

To examine the combined effects of phosphorus (P) nutrition and CO2 on photosynthesis, chlorophyll fluorescence (CF), and nutrient utilization and uptake, two controlled-environment experiments were conducted using 0.01, 0.05 and 0.20 mM external phosphate each at ambient and elevated CO2 (aCO2: 400 and eCO2: 800 mmol mol–1, respectively). The CF parameters were affected more by P nutrition than by CO2 treatment. Photoinhibition of photosystem II (PSII) was due to increased minimal CF (Fo') and decreased maximal CF (Fm'), and efficiency of energy harvesting (Fv'/Fm'). In addition, reduced electron transport rate (ETR), the quantum yield of PSII (FPSII) and CO2 assimilation …


Methods For Estimating Sediment Yield And Dam Capacity In The Great Lakes Watershed, Jennifer Hui Jan 2014

Methods For Estimating Sediment Yield And Dam Capacity In The Great Lakes Watershed, Jennifer Hui

Wayne State University Theses

Sedimentation is the most important factor in the longevity of dams built in the United States. As most dams are reaching their capacity for sediment storage, this study investigated the historical and predicted future rates of sediment accumulation as well as the remaining storage capacity. This study examined the mechanisms influencing sediment production and storage in the watershed to provide future insight regarding potential control of this process. Twelve reservoirs throughout the Great Lakes watershed were selected and analyzed for their greater applicability to the entire watershed. Both historic and new data were collected on these dams to determine how …


Carbon And Nitrogen Isotope Analysis Of Archaeological Faunal Material From Dutchess Quarry Caves, Ny, Jessica Zuhlke Jan 2014

Carbon And Nitrogen Isotope Analysis Of Archaeological Faunal Material From Dutchess Quarry Caves, Ny, Jessica Zuhlke

Legacy Theses & Dissertations (2009 - 2024)

The purpose of this study was to do an isotopic analysis to determine the carbon and nitrogen isotope concentrations of archaeological faunal material found in the Dutchess Quarry Caves in Orange County, NY. These isotope values were then used to compare the taxa from which the samples were taken to determine if and how trophic relationships were formed. The main focus of this comparison spotlighted a sample from a human femur; to establish the human's position trophically with the other large and small mammal samples collected. The human had been previously radiocarbon dated to have lived between 2877 and 3180 …


Convergence Of Dune Topography Among Multiple Barrier Island Morphologies, Jackie Ann Monge Jan 2014

Convergence Of Dune Topography Among Multiple Barrier Island Morphologies, Jackie Ann Monge

Theses and Dissertations--Geography

Wave-dominated and mixed tidal and wave energy barrier islands are assumed to have characteristic dune topographies that link to their macroscale form. However, there has been no systematic attempt to describe the linkage between barrier island macroscale form and dune topography. The goal of this thesis was to investigate how dune topographies correspond to a number of barrier island morphologies found along the southeastern U.S. Atlantic coast. Macroscale process-form variables were used to classify 77 islands into seven morphologic clusters. Islands from each cluster were selected and sites characteristic of the range of dune topographies within islands were characterized using …


Sedimentary Record Of Mid-Miocene Seismotectonic Activity In The Sinop Peninsula, North-Central Turkey, Ayhan Ilgar Jan 2014

Sedimentary Record Of Mid-Miocene Seismotectonic Activity In The Sinop Peninsula, North-Central Turkey, Ayhan Ilgar

Turkish Journal of Earth Sciences

The middle Miocene shallow-marine siliciclastic succession in the Sinop Peninsula, north-central Turkey, bears a well-preserved sedimentary record of syndepositional deformation associated with the buried escarpment of an oblique-slip dextral reverse fault and attributed to seismotectonic activity. The deposition occurred in a marginal trough at the edge of a tectonically inverted retroarc foreland basin of the Central Pontides. The synsedimentary deformation involved contemporaneous shoreface deposits and their consolidated, weakly cemented littoral substrate. Deformation features include neptunian dykes, convolute stratification, plumose transposition structure, injection dykes, diapirs, and large sandstone blocks dislodged from the fault escarpment. The genetic sequence of deformation structures deciphered …


Temporal Evolution Of The Water Characteristics In The Bays Along The Eastern Coast Of The Aegean Sea: Saros, İzmir, And Gökova Bays, Canan Eronat, Erdem Sayin Jan 2014

Temporal Evolution Of The Water Characteristics In The Bays Along The Eastern Coast Of The Aegean Sea: Saros, İzmir, And Gökova Bays, Canan Eronat, Erdem Sayin

Turkish Journal of Earth Sciences

The seasonal and interannual variability of the local hydrography in 3 bays (Saros, İzmir, and Gökova bays) along the eastern coast of the Aegean Sea are investigated using data sets collected from 1991 to 2010. The data cover the last major deep-water formation episodes and the Eastern Mediterranean Transient (EMT) relaxation period. Aegean Sea hydrology and water mass characteristics influence the water properties of the bays. The data suggest that Saros Bay (North Aegean Sea), İzmir Bay (Central Aegean Sea), and Gökova Bay (South Aegean Sea) have different physical processes and water characteristics. They have their own dynamics independent from …


The Utility Of Vulnerability Maps And Gis In Groundwater Management: A Case Study, Muhterem Demi̇roğlu, John Dowd Jan 2014

The Utility Of Vulnerability Maps And Gis In Groundwater Management: A Case Study, Muhterem Demi̇roğlu, John Dowd

Turkish Journal of Earth Sciences

Groundwater supplies are experiencing a critical shortage in arid and semiarid regions, as population growth, and hence demand, is not matched by the development of new water supplies. Groundwater is often the only water source in these areas, making the preservation of groundwater quality a critical issue. Powerful tools for groundwater protection are vulnerability maps, which can be used to identify protection zones. A number of factors influence aquifer vulnerability, including geology, geography, land use, and commercial and industrial development. These factors often display a complex spatial pattern easily addressed with GIS. Each factor is entered in the GIS as …


Analysis Of Precursory Seismicity Patterns In Zagros (Iran) By Cn Algorithm, Majid Maybodian, Mehdi Zare, Hosseyn Hamzehloo, Antonella Peresan, Anooshiravan Ansari, Giuliano F. Panza Jan 2014

Analysis Of Precursory Seismicity Patterns In Zagros (Iran) By Cn Algorithm, Majid Maybodian, Mehdi Zare, Hosseyn Hamzehloo, Antonella Peresan, Anooshiravan Ansari, Giuliano F. Panza

Turkish Journal of Earth Sciences

This study illustrates the application of the CN algorithm for the analysis of precursory seismicity patterns in the Zagros region (Iran), an area characterized by a complex seismotectonic setting and by remarkable seismic activity. CN is a formally defined and widely tested algorithm for intermediate-term middle-range earthquake prediction, based on the analysis of routinely compiled earthquake catalogs. To allow its application, the global and regional catalogs available for the territory of Iran have been analyzed so as to compile a data set sufficiently complete and homogeneous over a time span of about 3 decades, as required for CN application. A …


Responses Of Carbon Isotope Ratios Of C_3 Herbs To Humidity Index In Northern China, Xianzhao Liu, Qing Su, Chaokui Li, Yong Zhang, Qing Wang Jan 2014

Responses Of Carbon Isotope Ratios Of C_3 Herbs To Humidity Index In Northern China, Xianzhao Liu, Qing Su, Chaokui Li, Yong Zhang, Qing Wang

Turkish Journal of Earth Sciences

Uncertainties would exist in the relationship between delta^{13}C values and environmental factors such as temperature, resulting in unreliable reconstruction of paleoclimates. It is therefore important to establish a rational relationship between plant delta^{13}C and a proxy for paleoclimate reconstruction that can comprehensively reflect temperature and precipitation. By measuring the delta^{13}C of a large number of C_3 herbaceous plants growing in different climate zones in northern China and collecting early reported delta^{13}C values of C_3 herbs in this study area, the spatial features of delta^{13}C values of C_3 herbs and their relationships with humidity index were analyzed. The delta^{13}C values of …


Toxic Element Contamination In Waters From The Massive Sulfide Deposits And Wastes Around Giresun, Turkey, Necati̇ Karakaya, Muazzez Çeli̇k Karakaya Jan 2014

Toxic Element Contamination In Waters From The Massive Sulfide Deposits And Wastes Around Giresun, Turkey, Necati̇ Karakaya, Muazzez Çeli̇k Karakaya

Turkish Journal of Earth Sciences

This study assessed the quality of water polluted with mine drainage waters, some of which is used for drinking and agriculture, in the urban areas of the Giresun region, Turkey. A total of 40 water samples were collected from the main rivers and stream, spring, and drainage waters. All samples were analyzed for physical and chemical parameters. The tectonically controlled massive sulfide deposits hosted in the Maastrichtian-Eocene magmatic rocks are either active or have been abandoned. The main ore mineral assemblages are chalcopyrite, sphalerite, galena, and pyrite. The oxidation of the sulfide minerals in the deposits and wastes has caused …


Santonian-Campanian Biostratigraphy Of The Kalaat Senan Area (West-Central Tunisia), Zaineb Elamri, Dalila Zaghbib-Turki Jan 2014

Santonian-Campanian Biostratigraphy Of The Kalaat Senan Area (West-Central Tunisia), Zaineb Elamri, Dalila Zaghbib-Turki

Turkish Journal of Earth Sciences

The Santonian-Campanian (S/C) transition in the Kalaat Senan area is well exposed in the Assila Wadi (OA) section and consists of marls with indurate glauconitic levels towards the base. Standard Mediterranean ammonite biozonations could not be applied to this section because the biomarkers are absent. However, planktonic foraminiferal biozonation is more reliable for indicating the S/C boundary, and here we propose to use the last appearance datum of Dicarinella asymetrica as the index marker of this boundary. A high-resolution quantitative analysis of the planktonic foraminifera of the OA section allows us to define the main bioevents across the S/C transition …


Early Pleistocene Freshwater Communities And Rodents From The Pasinler Basin (Erzurum Province, North-Eastern Turkey), Davit Vasilyan, Simon Schneider, Memet Sali̇h Bayraktutan, Şevket Şen Jan 2014

Early Pleistocene Freshwater Communities And Rodents From The Pasinler Basin (Erzurum Province, North-Eastern Turkey), Davit Vasilyan, Simon Schneider, Memet Sali̇h Bayraktutan, Şevket Şen

Turkish Journal of Earth Sciences

An Early Pleistocene lacustrine faunal assemblage from Pasinler (Erzurum Province, north-eastern Turkey) is described, which encompasses 13 mollusc, 5 fish, 2 amphibian, 1 reptile, and 1 mammal species. The autochthonous freshwater mollusc fauna indicates shallow stagnant waters and a fine-sandy to muddy lake bottom, grown with submersed plants. The fish community (Leuciscus sp., Rutilus sp., Chondrostoma sp., Leuciscinae sp. 1 and 2, and Capoeta sp.) and autochthonous herpetofauna (Latonia sp. and Natrix sp.) provide evidence of a well-oxygenised palaeolake with rich periphyton and partially rocky to gravelly bottom. Moreover, the presence of the terrestrial snail Caspicyclotus cf. akramowsii, the peri- …


Neotectonics Of The Zanjan-Kazvin Area, Central Iran: Left Lateral Strike‐Slip Induced Restraining Stepovers, Moosarreza Toori, Gürol Seyi̇toğlu Jan 2014

Neotectonics Of The Zanjan-Kazvin Area, Central Iran: Left Lateral Strike‐Slip Induced Restraining Stepovers, Moosarreza Toori, Gürol Seyi̇toğlu

Turkish Journal of Earth Sciences

The neotectonics of the Zanjan-Kazvin area are dominated by the region-wide E-W trending left lateral strike-slip faults. These faults create restraining and releasing stepovers indicating strain partitioning. Instead of the NW-SE trending long range-parallel continuous thrust faulting suggested in previous studies, this paper demonstrates that there are E-W trending range-crossing left lateral strike-slip faults creating short range-parallel thrust faults in the restraining stepovers. Establishing this strike-slip-induced structural style might contribute to an understanding of the nature of the Elburz (Alborz) Mountains located between the Central Iran and Caspian blocks.


Miocene Palynoflora Of The Kocaçay And Cumaovası Basins: A Contribution To The Synthesis Of Miocene Palynology, Palaeoclimate, And Palaeovegetation In Western Turkey, Mi̇ne Sezgül Kayseri̇ Özer, Hasan Sözbi̇li̇r, Funda Akgün Jan 2014

Miocene Palynoflora Of The Kocaçay And Cumaovası Basins: A Contribution To The Synthesis Of Miocene Palynology, Palaeoclimate, And Palaeovegetation In Western Turkey, Mi̇ne Sezgül Kayseri̇ Özer, Hasan Sözbi̇li̇r, Funda Akgün

Turkish Journal of Earth Sciences

Palynofloras of the Kocaçay and Cumaovası basins in western Turkey that belong to a time-span from the late Early to late Middle Miocene (the late Burdigalian-Serravallian) are studied and compared with published palynofloras of Europe and Turkey. Palynological data and numerical climatic results obtained by the coexistence approach indicate palaeoclimate changed from warm subtropical to temperate during the late Burdigalian-Serravallian. Moreover, the palaeoclimates of the Kocaçay and Cumaovası basins are compared with continental palaeoclimatic records of coal-bearing sediments in western Turkey and current temperatures in the İzmir region. According to this comparison, palaeoclimatic results of these basins and other localities …


First Report Of Sphaeronitid Blastozoans (Echinodermata) In The Middle Ordovician Of The Taurides, Turkey, Elise Nardin, Mehmet Cemal Göncüoğlu, Bertrand Lefebvre Jan 2014

First Report Of Sphaeronitid Blastozoans (Echinodermata) In The Middle Ordovician Of The Taurides, Turkey, Elise Nardin, Mehmet Cemal Göncüoğlu, Bertrand Lefebvre

Turkish Journal of Earth Sciences

Articulated echinoderm remains are described for the first time in the Ordovician of Turkey. They occur massively, forming a relatively thick “cystoid bed” within the detrital limestone succession of the Sobova Formation (latest Dapingian–earliest Darriwilian) in the western Taurus Mountains. The “cystoid bed” encompasses a monospecific echinoderm assemblage of densely packed, 3-dimensionally preserved thecae. The presence of numerous suborganised plates with diplopore respiratory structures suggests probable affinities with sphaeronitid blastozoans. Comparable sphaeronitid dense beds are well known in the early Darriwilian of Baltica, and in the mid Darriwilian of the Middle East and Asian terranes.


New Fossils Of Gaindatherium (Rhinocerotidae, Mammalia) From The Middle Miocene Of Pakistan, Abdul Majid Khan, Esperanza Cerdeño, Muhammad Akhtar, Muhammad Akbar Khan, Ayesha Iqbal, Muhammad Mubashir Jan 2014

New Fossils Of Gaindatherium (Rhinocerotidae, Mammalia) From The Middle Miocene Of Pakistan, Abdul Majid Khan, Esperanza Cerdeño, Muhammad Akhtar, Muhammad Akbar Khan, Ayesha Iqbal, Muhammad Mubashir

Turkish Journal of Earth Sciences

New isolated teeth with maxillary and mandibular fragments from the Chinji Formation of the Lower Siwaliks are described and determined as Gaindatherium browni and Gaindatherium vidali. This material comes from the Middle Miocene of Lava and Dhok Bun Ameer Khatoon localities, northern Pakistan, and significantly increases the number of remains previously known for this rhinocerotid genus. Specimens from the Lava site determined as G. vidali present morphological differences with respect to those of G. browni, being similar to those of G. vidali from the Nagri Formation, showing a greater size. Previously, G. vidali was reported only from the Nagri Formation …


Reply To Comment By Erkül And Erkül On “Al-In-Hornblende Thermobarometry And Sr-Nd-O-Pb Isotopic Compositions Of The Early Miocene Alaçam Granite In Nw Anatolia (Turkey)”, Altuğ Hasözbek, Burhan Erdoğan, Muharrem Satir, Wolfgang Siebel, Erhan Akay, Güllü Deni̇z Doğan, Heinrich Taubald Jan 2014

Reply To Comment By Erkül And Erkül On “Al-In-Hornblende Thermobarometry And Sr-Nd-O-Pb Isotopic Compositions Of The Early Miocene Alaçam Granite In Nw Anatolia (Turkey)”, Altuğ Hasözbek, Burhan Erdoğan, Muharrem Satir, Wolfgang Siebel, Erhan Akay, Güllü Deni̇z Doğan, Heinrich Taubald

Turkish Journal of Earth Sciences

No abstract provided.


Capacitively Coupled And Direct-Current Resistivity Surveys Of Selected Reaches Of Cozad, Thirty-Mile, Orchard-Alfalfa, Kearney, And Outlet Canals In Nebraska, 2012-13, Christopher M. Hobza, Bethany L. Burton, Jeffrey E. Lucius, Ryan E. Tompkins Jan 2014

Capacitively Coupled And Direct-Current Resistivity Surveys Of Selected Reaches Of Cozad, Thirty-Mile, Orchard-Alfalfa, Kearney, And Outlet Canals In Nebraska, 2012-13, Christopher M. Hobza, Bethany L. Burton, Jeffrey E. Lucius, Ryan E. Tompkins

United States Geological Survey: Water Reports and Publications

Understanding the spatial characteristics of leakage from canals is critical to effectively managing and utilizing water resources for irrigation and hydroelectric purposes. Canal leakage in some parts of Nebraska is the primary source of water for groundwater recharge and helps maintain the base flow of streams. Because surface-water supplies depend on the streamflow of the Platte River and the available water stored in upstream reservoirs, water managers seek to minimize conveyance losses, which can include canal leakage. The United States Geological Survey, in cooperation with the Central Platte Natural Resources District and Nebraska Public Power District, used capacitively coupled (CC) …


Emplacement Of Pleistocene Basalt Flows Near Mccoy, Colorado, Andrea Bowen Jan 2014

Emplacement Of Pleistocene Basalt Flows Near Mccoy, Colorado, Andrea Bowen

Electronic Theses and Dissertations

No abstract provided.


Deformation Mechanisms In Mylonites At Fletcher Peak, Washington County, Me, Ariana S. Boyd Jan 2014

Deformation Mechanisms In Mylonites At Fletcher Peak, Washington County, Me, Ariana S. Boyd

Honors Theses

Mylonite formation and development is dependent on a number of factors including temperature, strain rate, and fluid fugacity. All three factors affect flow stress and viscosity; thus, a variance in each will affect the development of mylonites. This study focuses on factors leading to the formation of mylonite surrounded by ultramylonite of the same protolith, along-strike to one another at the center of a fault zone. The rocks in question are from the Deblois granite cut by the Kellyland fault zone, a ductile strike-slip fault zone within the larger Norumbega fault system in eastern Maine. The Deblois granite as a …


Production And Transformation Of Dissolved Neutral Sugars And Amino Acids By Bacteria In Seawater, L. Jørgensen, O. J. Lechtenfeld, Ronald Benner, M. Middleboe, C. A. Stedmon Jan 2014

Production And Transformation Of Dissolved Neutral Sugars And Amino Acids By Bacteria In Seawater, L. Jørgensen, O. J. Lechtenfeld, Ronald Benner, M. Middleboe, C. A. Stedmon

Faculty Publications

Dissolved organic matter (DOM) in the ocean consists of a heterogeneous mixture of molecules, most of which are of unknown origin. Neutral sugars and amino acids are among the few recognizable biomolecules in DOM, and the molecular composition of these biomolecules is shaped primarily by biological production and degradation processes. This study provides insight into the bioavailability of biomolecules as well as the chemical composition of DOM produced by bacteria. The molecular compositions of combined neutral sugars and amino acids were investigated in DOM produced by bacteria and in DOM remaining after 32 days of bacterial degradation. Results from bioassay …


Fluctuations In Resistivity In The Tuscaloosa Marine Shale, Southwest Mississippi And Southeast Louisiana, Thomas Hetherington Story Jan 2014

Fluctuations In Resistivity In The Tuscaloosa Marine Shale, Southwest Mississippi And Southeast Louisiana, Thomas Hetherington Story

Electronic Theses and Dissertations

The Tuscaloosa Marine Shale in southwest Mississippi and Southeast Louisiana's Florida Parishes has become an unconventional target for the exploration and production of oil. Spurred by early estimates of over 7 billion barrels of oil in place, the target region for this production is the basal portion of the shale where a continuous increase in resistivity greater than 5 Ohmm can be observed. This increase was originally attributed solely to the generation of hydrocarbons from the organic matter contained within the shale, with the presence of the oil and gas impeding the flow of electrons through what would normally be …


A Quantitative Analysis Of White-Tailed Deer Harvest Across States And Counties, Rebecca Lynne Cain Jan 2014

A Quantitative Analysis Of White-Tailed Deer Harvest Across States And Counties, Rebecca Lynne Cain

Theses and Dissertations

White-tailed deer (Odocoileus virginianus) have gone from locally extirpated to overabundant in many areas in the United States since the early 1900s. Ecosystems with chronically overabundant populations experience many disastrous effects resulting from the selective browsing behavior of deer. White-tailed deer are managed at the state level resulting in different management strategies, harvest data collection, and deer management goals between states. However recreational hunting is the primary tool used by wildlife agencies to control population growth. As such, it is beneficial to understand the influence each regulatory variable has on white-tailed deer harvest.

For this research, I compiled historical harvest …


From Marsquakes To Terraforming: The Role Of Planetary Geology In Science Fiction Literature, Katherine Shover 14 Jan 2014

From Marsquakes To Terraforming: The Role Of Planetary Geology In Science Fiction Literature, Katherine Shover 14

Honor Scholar Theses

None


Contrasting Biogeochemical Cycles Of Cobalt In The Surface Western Atlantic Ocean, Gabrial Dulaquais, Marie Boye, Rob Middag, Stephanis Owens, Viene Puigcorbe, Ken Buesseler, Pere Masque´, Hein J. De Baar, Xavier Carton Jan 2014

Contrasting Biogeochemical Cycles Of Cobalt In The Surface Western Atlantic Ocean, Gabrial Dulaquais, Marie Boye, Rob Middag, Stephanis Owens, Viene Puigcorbe, Ken Buesseler, Pere Masque´, Hein J. De Baar, Xavier Carton

Research outputs 2014 to 2021

Dissolved cobalt (DCo; 0.2μm; 10%) to the DCo stock of the mixed layer in the equatorial and north subtropical domains. Biotic and abiotic processes as well as the physical terms involved in the biogeochemical cycle of Co were defined and estimated. This allowed establishing the first global budget of DCo for the upper 100m in the western Atlantic. The biological DCo uptake flux was the dominant sink along the section, as reflected by the overall nutrient-type behavior of DCo. The regeneration varied widely within the different biogeochemical domains, accounting for 10% of the DCo-uptake rate in the subarctic gyre and …


Geospatial Data Pre-Processing On Watershed Datasets: A Gis Approach, Sreedhar Nallan, Leisa Armstrong, Barry Croke, Amiya K. Tripathy Jan 2014

Geospatial Data Pre-Processing On Watershed Datasets: A Gis Approach, Sreedhar Nallan, Leisa Armstrong, Barry Croke, Amiya K. Tripathy

Research outputs 2014 to 2021

Spatial data mining helps to identify interesting patterns from the spatial data sets. However, geo spatial data requires substantial data pre-processing before data can be interrogated further using data mining techniques. Multi-dimensional spatial data has been used to explain the spatial analysis and SOLAP for pre-processing data. This paper examines some of the methods for pre-processing of the data using Arc GIS 10.2 and Spatial Analyst with a case study dataset of a watershed.


Regulation Of Artisanal Small Scale Gold Mining (Asgm) In Ghana And Indonesia As Currently Implemented Fails To Adequately Protect Aquatic Ecosystems, Karunia F. Macdonald, Mark A. Lund, Melanie L. Blanchette, Clinton D. Mccullough Jan 2014

Regulation Of Artisanal Small Scale Gold Mining (Asgm) In Ghana And Indonesia As Currently Implemented Fails To Adequately Protect Aquatic Ecosystems, Karunia F. Macdonald, Mark A. Lund, Melanie L. Blanchette, Clinton D. Mccullough

Research outputs 2014 to 2021

Artisanal small scale gold mining (ASGM) operations are largely unregulated, informal and transient. Rudimentary mining and processing techniques used in ASGM often result in degraded environmental, safety, health and social conditions. ASGM requires permanent sources of water, placing most operations close to natural water bodies. Until recently, the impact on these environments has been largely overlooked, with most studies focussing primarily on mercury contamination and health concerns. Based on Ghanaian and Indonesian experiences, regulation of ASGM is a good step toward improvement, but here we argue that regulation alone is insufficient to improve environmental performance, particularly when the impacts of …


Hydrological Influences On Ecological Zonation In A Salt Marsh Tidal Creek Basin: Crab Haul Creek, South Carolina, Usa, Elizabeth Madsen Jan 2014

Hydrological Influences On Ecological Zonation In A Salt Marsh Tidal Creek Basin: Crab Haul Creek, South Carolina, Usa, Elizabeth Madsen

Theses and Dissertations

Ecological zones in a salt marsh are controlled by many factors, including hydroperiod, elevation, soil salinity, groundwater flow, competition, and nutrient/oxygen availability. The primary driving factor(s) are still debated, but most models of zonation consider elevation or hydroperiod as the key factor. This project is designed to gather high-resolution aerial images from a helium balloon kite (Helikite) to improve our understanding of the influence of hydroperiod on zonation. The Helikite was used to capture aerial photographs of Crab Haul Creek Basin, the most landward salt marsh basin in North Inlet, South Carolina. Near-IR photographs were taken from 75-100m altitude to …


Radon Loss From Zircon: Effects Of Microstructure On Radon Emanation And Diffusion, Marty Eakin Jan 2014

Radon Loss From Zircon: Effects Of Microstructure On Radon Emanation And Diffusion, Marty Eakin

Wayne State University Theses

Radon emanation from rocks and minerals is ubiquitous, but the mechanisms of radon loss are not well understood. Quantification of radon emanation rates from zircon has potential bearing on the reliability of U-Pb ages of zircon bearing rocks. The 238U decay chain includes 222Rn, a noble gas, which has a half-life of 3.82 days and can escape from the crystal structure of zircon if sufficient pathways exist, or by recoil if the parent 238U was very near the outer edge of the crystal. Loss of 222Rn ultimately leads to a deficiency of 206Pb, resulting in discordance between 238U-206Pb, 235U-207Pb, and …


Evaluating Spatial Outliers And Integrating Temporal Data In Air Pollution Models For The Detroit-Windsor Airshed, Brendan Francis O'Leary Jan 2014

Evaluating Spatial Outliers And Integrating Temporal Data In Air Pollution Models For The Detroit-Windsor Airshed, Brendan Francis O'Leary

Wayne State University Theses

The heterogeneous nature of urban air complicates human exposure estimates and creates a need for accurate, highly detailed spatiotemporal air contaminant models. The study expands on previous investigations by the Geospatial Determinants of Health Outcomes Consortium that examined relationships between air pollutant distributions and asthma exacerbations. Two approaches, the removal of spatial data outliers and the integration of spatial and temporal data, were used to refine air quality models in the Detroit and Windsor international airshed. The evaluation of associations between the resulting air quality models and asthma exacerbations in Detroit and Windsor revealed weaker correlations with spatial outliers removed …