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Articles 1801 - 1830 of 3985
Full-Text Articles in Entire DC Network
Recirculation Over Complex Terrain, Eric Kutter, Chuixiang Yi, George Hendrey, Heping Liu, Timothy Eaton, Wenge Ni-Meister
Recirculation Over Complex Terrain, Eric Kutter, Chuixiang Yi, George Hendrey, Heping Liu, Timothy Eaton, Wenge Ni-Meister
Publications and Research
This study generated eddy covariance data to investigate atmospheric dynamics leeward of a small, forested hillside in upstate New York. The causes and effects of recirculation eddies were examined to support the larger goal of improving measurement of the exchange of energy, moisture, and trace gases between the terrestrial biosphere and the atmosphere over complex terrain. Sensors operated at five different altitudes on two separate towers—one at the top of the hill and one down the slope to the east—for approximately 8 weeks in the spring of 2013. During the experiment, the vertical potential temperature gradient was found to be …
Global Land Carbon Sink Response To Temperature And Precipitation Varies With Enso Phase, Yuanyuan Fang, Anna M. Michalak, Christopher R. Schwalm, Deborah N. Huntzinger, Joseph A. Berry, Philippe Ciais, Shilong Piao, Benjamin Poulter, Joshua B. Fisher, Robert B. Cook, Daniel Hayes, Maoyi Huang, Akihiko Ito, Atul Jain, Huimin Lei, Chaoqun Lu, Jiafu Mao, Nicholas C. Parazoo, Shushi Peng, Daniel M. Ricciuto, Xiaoying Shi, Bo Tao, Hanqin Tian, Weile Wang, Yaxing Wei, Jia Yang
Global Land Carbon Sink Response To Temperature And Precipitation Varies With Enso Phase, Yuanyuan Fang, Anna M. Michalak, Christopher R. Schwalm, Deborah N. Huntzinger, Joseph A. Berry, Philippe Ciais, Shilong Piao, Benjamin Poulter, Joshua B. Fisher, Robert B. Cook, Daniel Hayes, Maoyi Huang, Akihiko Ito, Atul Jain, Huimin Lei, Chaoqun Lu, Jiafu Mao, Nicholas C. Parazoo, Shushi Peng, Daniel M. Ricciuto, Xiaoying Shi, Bo Tao, Hanqin Tian, Weile Wang, Yaxing Wei, Jia Yang
Plant and Soil Sciences Faculty Publications
Climate variability associated with the El Niño-Southern Oscillation (ENSO) and its consequent impacts on land carbon sink interannual variability have been used as a basis for investigating carbon cycle responses to climate variability more broadly, and to inform the sensitivity of the tropical carbon budget to climate change. Past studies have presented opposing views about whether temperature or precipitation is the primary factor driving the response of the land carbon sink to ENSO. Here, we show that the dominant driver varies with ENSO phase. Whereas tropical temperature explains sink dynamics following El Niño conditions (r TG,P = 0.59, p …
Receiver Function And Gravity Constraints On Crustal Structure And Vertical Movements Of The Upper Mississippi Embayment And Ozark Uplift, Lin Liu, Stephen S. Gao, Kelly H. Liu, Kevin Lee Mickus
Receiver Function And Gravity Constraints On Crustal Structure And Vertical Movements Of The Upper Mississippi Embayment And Ozark Uplift, Lin Liu, Stephen S. Gao, Kelly H. Liu, Kevin Lee Mickus
Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works
The Upper Mississippi Embayment (UME), where the seismically active New Madrid Seismic Zone resides, experienced two phases of subsidence commencing in the Late Precambrian and Cretaceous, respectively. To provide new constraints on models proposed for the mechanisms responsible for the subsidence, we computed and stacked P-to-S receiver functions recorded by 49 USArray and other seismic stations located in the UME and the adjacent Ozark Uplift and modeled Bouguer gravity anomaly data. The inferred thickness, density, and Vp/Vs of the upper and lower crustal layers suggest that the UME is characterized by a mafic and high-density upper crustal …
The Effect Of Watershed Runoff And Sediment Resuspension On Turbidity And Sediment Deposition In St. John, Us Virgin Islands: Implications For Watershed And Marine Development And Restoration In Bays With Coral Reefs, Stephen E. Campbell
Theses
In the US Virgin Islands (USVI), land-based (terrigenous) sedimentation has been identified as a major cause of coral stress. Development, such as the building of unpaved roads in steep coastal watersheds, has increased sediment yields and marine terrigenous sedimentation by up to an order of magnitude above background levels. When activated during storm events, ephemeral streams transport sediment from the watershed to coastal waters. Once deposited on the seafloor, resuspension of benthic sediments can further increase turbidity and deposition. However, isolating the relative contributions of runoff and resuspension to turbidity and deposition using conventional sediment trap monitoring has been challenging. …
Evaluating Relationships Between Rock Strength And Longitudinal Stream Profile Morphometry In The Southern Guadalupe Mountains, Texas, Samuel T. Schoenmann
Evaluating Relationships Between Rock Strength And Longitudinal Stream Profile Morphometry In The Southern Guadalupe Mountains, Texas, Samuel T. Schoenmann
Theses and Dissertations
Landscapes record information about the tectonic, climatic, and lithologic environments in which they form (Yang et al., 2015). When one or more of these environmental conditions change spatially or temporally, the landscape responds through erosion and thus, develops representative geomorphic features (Ritter et al., 2011). Since the nineteenth century, it has been clear that bedrock strength and erodibility play an important role in landscape evolution and geomorphology (Lifton et al., 2009). However, the nuances of variable erodibility remain poorly understood. The implications of this limited understanding lies within landscape evolution models. While these models show strong qualitative relationships between longitudinal …
Development Of Geospatial And Temporal Characteristics For Hispaniola’S Lake Azuei And Enriquillo Using Landsat Imagery, Mahrokh Moknatian, Michael Piasecki, Jorge Gonzalez
Development Of Geospatial And Temporal Characteristics For Hispaniola’S Lake Azuei And Enriquillo Using Landsat Imagery, Mahrokh Moknatian, Michael Piasecki, Jorge Gonzalez
Publications and Research
In this paper, we used Landsat imagery for water body identification to create a novel 36-year surface area extent time series for lakes Azuei (Haiti) and Enriquillo (Dominican Republic) aimed at illuminating the dramatic temporal changes of these two lakes not just at yearly but at monthly or even sub-monthly scales. We used the Normalized Difference Water Index (NDWI) to extract water features and we also used spatial differentiation and thresholding techniques to remove clouds and associated shadows from the scene that were then passed through gap filling algorithms to complete and extract the lake extent polygons. We also explored …
An Operational Drought Prediction Framework With Application Of Vine Copula Functions, Mahkameh Zarekarizi
An Operational Drought Prediction Framework With Application Of Vine Copula Functions, Mahkameh Zarekarizi
Student Research Symposium
Early and accurate drought predictions can benefit water resources and emergency managers by enhancing drought preparedness. Soil moisture memory is shown to contain helpful information for prediction of future values. This study uses the soil moisture memory to predict their future states via multivariate statistical modeling. We present a drought forecasting framework which issues monthly and seasonal drought forecasts. This framework estimates droughts with different lead times and updates the forecasts when more data become available. Forecasts are generated by conditioning future soil moisture values on antecedent drought status. The statistical model is initialized by soil moisture simulations retrieved from …
Locomotion And Skeletal Morphology Of Late Cretaceous Mosasaur, Tylosaurus Proriger, Jesse A. Carpenter
Locomotion And Skeletal Morphology Of Late Cretaceous Mosasaur, Tylosaurus Proriger, Jesse A. Carpenter
Honors College Theses
Mosasaurs (Reptilia: Squamata) are apex marine predators from the Late Cretaceous (Turonian to Maastrichtian) epicontinental seas of North America, Africa, Europe, and Asia. From previous studies, it has been suggested that this group trends towards increased rib compactness, lengthening and increased posterior inclination of neural spines of intermediate and terminal caudal vertebrae to support a caudal fluke, and a transition from anguilliform to carangiform locomotion, closer to thunniform in pelagic adapted species. This study examined multiple Tylosaurus specimens using centrum length/width (CL/CW) and width/height (CW/CH) ratios along with neural spine height and angle of posterior inclination to (1) describe the …
Characterizing Subsurface Void Spaces And Water Distribution And Flow Patterns In Cave Hill Karst Using Resistivity, Jacob A. Gochenour
Characterizing Subsurface Void Spaces And Water Distribution And Flow Patterns In Cave Hill Karst Using Resistivity, Jacob A. Gochenour
Senior Honors Projects, 2010-2019
Describing the distribution of groundwater is essential in understanding the evolution of geomorphologic features in karst topography. Electrical resistivity allows us to find a model of subsurface distribution of resistivity that enables the visual recognition of groundwater and void spaces. The purpose of this research is to implement electrical resistivity to describe the spatial relationship of groundwater and karstic features at Grand Caverns National Natural Landmark, Grottoes, Virginia. Two locations of interest, a karstic swale and sinkhole area, were identified for the deployment of electrical resistivity. Both, dipole-dipole and Schlumberger arrays were collected for each deployment. A total of ten …
Summer Precipitation Occurrence Effect On Two Passerine Species In Thule, Greenland, Sara E. Baugh
Summer Precipitation Occurrence Effect On Two Passerine Species In Thule, Greenland, Sara E. Baugh
Celebration of Learning
Climate change is occurring at a faster rate in the Arctic than the rest of the globe, causing temperature rises at twice the rate of the global average and increased summer precipitation in the form of rain. These precipitation events are predicted to affect migratory bird species that breed throughout the Arctic. Increased occurrence of heavy rainstorms indirectly affect bird populations by impacting distribution and abundance of food supply, and directly by increasing mortality rates of juveniles. Studies conducted on bird species throughout the low Arctic regions; have shown that it is not the total precipitation of a breeding season …
Nutrient Variations Of Six Surface Water Bodies In Mchenry County, Il, Jacob Piske
Nutrient Variations Of Six Surface Water Bodies In Mchenry County, Il, Jacob Piske
Celebration of Learning
This research analyzes water quality from several ponds in McHenry County, Illinois, with a goal of developing a understanding of pollution sources and temporal variations in concentrations of nitrate, potassium, phosphorus, chlorine, and sodium. Over the past 25 years, the population of McHenry County has grown rapidly, with residential developments expanding into former farmlands. Yet, the county remains heavily agricultural, with roughly 60% of the surface area used for agricultural purposes. Concentrations of NO3-, P+, K+, Cl-, and Na+ were analyzed from six sites: two in subdivisions, two in farmland, and two near major highways. Data were collected once a …
Evaluating Fault-Line Escarpment Exposure In The Guadalupe Mountains Of West Texas And New Mexico, Audrey Anne Happel
Evaluating Fault-Line Escarpment Exposure In The Guadalupe Mountains Of West Texas And New Mexico, Audrey Anne Happel
Theses and Dissertations
The Permian stratigraphy of the Guadalupe Mountains is well-known due to the impeccable exposure of Permian strata along distinct escarpments that define the boundaries of the range. Even though the Permian strata have been closely examined to understand the associated petroleum reservoirs in the adjacent Delaware basin, little work has been done on the escarpments that expose the well-known rocks at the surface by way of tectonic and erosional processes. The development of escarpments are directly affected by multiple processes that create the landscape, and can be used as a tool to temporally and spatially constrain tectonic and erosional activity …
Global Deforestation Prediction: Summer Internship At Clark Labs, Tianze Li, Yahsee Joshi
Global Deforestation Prediction: Summer Internship At Clark Labs, Tianze Li, Yahsee Joshi
Sustainability and Social Justice
This paper is a description of our internship with Clark Labs in the summer of 2016. We worked as research assistants in the Deforestation Risk Prediction project for Ecosystem Services team. This goal of the project was to predict deforestation at global, continental and national level. Our responsibilities were to choose the variables that may influence the deforestation and to use Land Change Modeler in TerrSet to test the variables and create the deforestation prediction maps. We highly recommend this internship with Clark Labs to other GISDE students who are interested in land change analysis.
Geoscientists-In-The-Park Summer Internship Mapping Shoreline Change With The National Park Service, Michael P. Endicott
Geoscientists-In-The-Park Summer Internship Mapping Shoreline Change With The National Park Service, Michael P. Endicott
Sustainability and Social Justice
This project paper details the activities carried out as a Geologist/GIS Specialist in the Gateway National Recreation Area as a part of the Geoscientists-In-The-Park internship program. The focus of this position was on supporting the geomorphological monitoring efforts of the National Park Service. This was accomplished through a combination of field data collection, GIS analysis, report writing, and project work. By the end of the internship, substantial progress was made to the formation of Gateway’s Annual 1D and 2D report for 2015-2016, field data were collected for the 2016 summer season, changes in geomorphology were explored and summarized for the …
Development Of A Multiband Remote Sensing System For Determination Of Unsaturated Soil Properties, Cyrus D. Garner
Development Of A Multiband Remote Sensing System For Determination Of Unsaturated Soil Properties, Cyrus D. Garner
Graduate Theses and Dissertations
A multiband system including active microwave sensing and visible-near infrared reflectance spectroscopy was developed to measure unsaturated soil properties in both field and laboratory environments. Remote measurements of soil volumetric water content (θv), soil water matric potential (ψ), and soil index properties (liquid limit [LL], plastic limit [PL], and clay fraction [CF]) were conducted. Field-based measurement of θv was conducted using a ground-based radar system and field measurements within 10 percentage points of measurements acquired with traditional sampling techniques were obtained. Laboratory-based, visible and near infrared spectroscopy was found to be capable of obtaining empirical, soil specific regression functions (partial …
Rock Art Management And Landscape Change: Mixed Field Assessment Techniques For Cultural Stone Decay, Kaelin M. Groom
Rock Art Management And Landscape Change: Mixed Field Assessment Techniques For Cultural Stone Decay, Kaelin M. Groom
Graduate Theses and Dissertations
As tourism continues to grow as one of the world’s most ubiquitous markets, the development and promotion of non-invasive techniques for cultural stone decay analysis and landscape change are vital to establishing conditional base-lines to best aid cultural heritage management (CRM) efficacy. Using rock art as a medium, this dissertation presents three independent case studies employing the Rock Art Stability Index (RASI) and repeat photography to explore the merits of mixed rapid field assessment techniques in relation to CRM and heritage tourism. While rock art is only one example of irreplaceable world heritage resources, examining how they decay and what …
An Analysis Of The Relationship Between Snowpack And Groundwater Across Utah Watersheds., Samuel Wright
An Analysis Of The Relationship Between Snowpack And Groundwater Across Utah Watersheds., Samuel Wright
Electronic Theses and Dissertations
This thesis examined what type of relationship existed between snow water equivalence (SWE) volume and groundwater elevation within six sub-watersheds in Utah. Data was gathered on SWE from seventeen SNOTEL sites and groundwater elevation data was gathered from six continuously monitored groundwater wells. This data was gathered for January through May for 2011, 2013, and 2014 in order to represent the water conditions that were above average, below average, and average respectively. Using MLR formulas the total SWE for each sub-watershed was determined for each year/month. Afterwards a correlation analysis was performed to determine if any association existed between SWE …
A Geophysical Analysis Of The Great Falls Tectonic Zone And The Surrounding Area, Montana Usa, Travis Lane Fultz
A Geophysical Analysis Of The Great Falls Tectonic Zone And The Surrounding Area, Montana Usa, Travis Lane Fultz
Graduate Theses/Dissertations
The Great Falls Tectonic Zone (GFTZ) is a northeast trending zone of high angle faults and lineaments extending from northeastern Idaho into Saskatchewan, Canada. The GFTZ is believed to have facilitated the collision between the Archean Wyoming and Hearne cratons. Previous geophysical studies have analyzed seismic refraction data across the boundary between the Paleoproterozoic GFTZ and Archean Wyoming Craton (WC), this indicated the lower crustal layer thickens as it dips beneath the boundary towards the WC. In this study, three 2 dimensional (2D) gravity models that crossed the central region of the GFTZ were produced using constraints from existing geologic …
Cyclostratigraphic Trends Of Δ13c In Upper Cambrian Strata, Great Basin, Usa: Implications For Astronomical Forcing, Wesley Donald Weichert
Cyclostratigraphic Trends Of Δ13c In Upper Cambrian Strata, Great Basin, Usa: Implications For Astronomical Forcing, Wesley Donald Weichert
Graduate Theses/Dissertations
Composite geochemical studies of carbonate isotope values (δ13C) by other investigators have established that the Cambrian period is punctuated by a series of significant, globally correlated, positive and negative δ13C excursions. However, it remains unclear if low-amplitude secular variations in δ13C values exist superimposed on, or between large-scale perturbations in the Cambrian carbon cycle, especially in cyclic successions. Rocks of Steptoean-Sunwaptan (Paibian-Jiangshanian) stage, exposed in the Great Basin of Utah and Nevada, are excellent candidates for testing the hypothesis that sedimentary cycles record minor variations in Earth's orbit (Milankovitch cycles) through application of high-resolution chemostratigraphic analysis. High-resolution δ13C data was …
Geochronology Of Calc-Alkaline Ash Flow Tuff Units In The Ogollon Datil Volcanic Field, Southern New Mexico: U-Pb In Zircon, Shannon Porter Rentz
Geochronology Of Calc-Alkaline Ash Flow Tuff Units In The Ogollon Datil Volcanic Field, Southern New Mexico: U-Pb In Zircon, Shannon Porter Rentz
Graduate Theses/Dissertations
Caldera systems are capable of outputting voluminous quantities of volcaniclastic material with wide ranging negative environmental impacts. Determining the behaviors of previously erupted caldera systems may help inform predictive models used to evaluate hazards and assess risks for analogous currently active volcanic systems. The Mogollon-Datil volcanic field (MDVF) is a 40-24 Ma cluster of caldera activity in southern New Mexico tied to the subduction, and possible delamination, of the Farallon plate beneath the North American plate. A regional ignimbrite flare up from 36-24 Ma produced at least 28 caldera-forming eruptions. The calc-alkaline magmatism of three calderas in this field (the …
Lithospheric Evaluation Of The Mid-Continental Rift System In Iowa From A Gravity And Magnetic Analysis, Moamen Mohamed Almaz
Lithospheric Evaluation Of The Mid-Continental Rift System In Iowa From A Gravity And Magnetic Analysis, Moamen Mohamed Almaz
Graduate Theses/Dissertations
The Proterozoic Midcontinent Rift System (MCRS) is considered one of the most important tectonic features in North America and was formed during a continental breakup event at 1.1 Ga (billion years). The MCRS is totally covered by Phanerozoic sedimentary rocks except in the Lake Superior region. Consequently, the geological characteristics of the MCRS are primarily inferred from extrapolations from the outcrop areas, drill holes, and from a variety of geophysical investigations. Iowa has a large segment of the MCRS which to date has only been partially investigated geophysically with little information regarding the lower crustal and upper mantle structure under …
Geomorphic Effects Of Logging Railbeds On An Ozarks Headwater Stream, Mark Twain National Forest, Missouri, Nickolas S. Bradley
Geomorphic Effects Of Logging Railbeds On An Ozarks Headwater Stream, Mark Twain National Forest, Missouri, Nickolas S. Bradley
Graduate Theses/Dissertations
Geomorphic characteristics of headwater streams draining the Missouri Ozarks have not been studied as much as larger rivers in the region. Further, while the effects of historical logging on channel form and sediment supply have been identified, no studies have investigated the effects of logging tramways constructed along Ozark headwater rivers. This study examines the geomorphic characteristics and channel disturbances of Tram Hollow (1.67 km2) within the Mark Twain National Forest in the Ozark Highlands. The purpose of this study is to classify and quantify natural and disturbed channel morphology in Tram Hollow which has been affected by …
Influence Of Prescribed Burning On Upland Soil Properties In Mark Twain National Forest, Southeast Missouri Ozarks, Megan Lynn Hente
Influence Of Prescribed Burning On Upland Soil Properties In Mark Twain National Forest, Southeast Missouri Ozarks, Megan Lynn Hente
Graduate Theses/Dissertations
In the Mark Twain National forest there is a collaborative effort to restore parts of the forest to its original shortleaf pine-oak woodland areas by using a combination of silviculture and prescribed fire. The purpose of this project is to assess the effects of prescribed burning on upland forest and soil physical properties that influence erosion processes across a gradient of burned sites of different ages and unburned sites. A combination of geospatial, field, laboratory, statistical (one-way ANOVA) and modeling (USLE) methods were used to assess the effects of prescribed burns on forest and soil characteristics in Big Barren Creek …
Geomorphic Characteristics And Sediment Transport In Natural And Channelized Reaches Of Big Barren Creek, Southeast Missouri, Matthew S. Thies
Geomorphic Characteristics And Sediment Transport In Natural And Channelized Reaches Of Big Barren Creek, Southeast Missouri, Matthew S. Thies
Graduate Theses/Dissertations
Channelization, levee construction, and gravel mining are land management practices that are used for flood control. However, they often alter the balance between sediment supply and available sediment transporting power in streams, causing channel instability. Streams can respond to instability through channel incision and sediment aggradation which can degrade riparian habitat, increase flood risks, and cause property damage. These problems have been observed along segments of Big Barren Creek, which drains 190 km² of the Missouri Ozarks in Mark Twain National Forest. Field assessment and modeling methods were used to evaluate the spatial distribution of channel instability along the upper …
Deposition Patterns And Rates Of Mining-Contaminated Sediment Within A Sedimentation Basin System, S.E. Missouri, Joshua Carl Voss
Deposition Patterns And Rates Of Mining-Contaminated Sediment Within A Sedimentation Basin System, S.E. Missouri, Joshua Carl Voss
Graduate Theses/Dissertations
Flooding events exert a dominant control over the deposition and formation of floodplains. The rate at which floodplains form depends on flood magnitude, frequency, and duration, and associated sediment transport capacity and supply. While it is known that sediment in the Big River is contaminated from historical mining, little is known about the patterns and rates of deposition on floodplains, especially those that have been modified for remediation purposes. The goal of this study was to evaluate the influence of flood characteristics and topography on contemporary deposition patterns and rates in a sedimentation basin system located within a floodplain along …
Using Survey Data And Hec-Ras Modeling To Assess A Riffle-Remediation Structure On The Big River, Bonne Terre, Missouri, Nichole Renee Weedman
Using Survey Data And Hec-Ras Modeling To Assess A Riffle-Remediation Structure On The Big River, Bonne Terre, Missouri, Nichole Renee Weedman
Graduate Theses/Dissertations
Sediment transport and deposition in river channels can vary for many reasons including flooding, dredging, channel velocity, and grain size. On the Big River, the Army Corps of Engineers constructed a riffle ramp structure to trap and remediate lead-contaminated sediments. The performance of the structure is unknown. The goal of this study is to evaluate the storage capabilities of the riffle structure. To do this, survey data was collected to analyze sediment storage and entered into the HEC-RAS 5.0 to model the hydraulics of the channel before and after the riffle installation. Samples were collected to assess the level of …
Assessing Landslide Susceptibility With Gis Using Qualitative And Quantitative Methods In Knox County, Nebraska, Christian J. Cruz
Assessing Landslide Susceptibility With Gis Using Qualitative And Quantitative Methods In Knox County, Nebraska, Christian J. Cruz
Department of Geography: Dissertations, Theses, and Student Research
This thesis assesses landslide susceptibility using data from LiDAR DEMs, land cover, and soil surveys. Data were assessed quantitatively through Bayesian logistic regression within a geographic information system (GIS) and statistical software to produce a landslide susceptibility map. The study area exhibits moderate relief where bluffs along the Missouri River valley gradually recede into rolling loess-mantled hills further to the south and southeast in Knox County. The six factors used to determine susceptibility to landslides are: land cover, parent material, slope aspect, slope curvature slope degree, and soil series. My findings show an increase in slope is the most significant …
Petrography And Geochemistry Of Oligocene Rhyolitic Volcanic Rocks, Western Mogollon-Datil Volcanic Field, New Mexico, Emily Elizabeth Salings
Petrography And Geochemistry Of Oligocene Rhyolitic Volcanic Rocks, Western Mogollon-Datil Volcanic Field, New Mexico, Emily Elizabeth Salings
Graduate Theses/Dissertations
The Mogollon-Datil volcanic field (MDVF), located in southern New Mexico, is the remnant of extreme and punctuated volcanism over ~12 m.y. of activity. The Bursum caldera is the youngest of three nested calderas in the Mogollon Mountains in the western MDVF. Here I present data from a high-silica, large volume tuff associated with the Bursum caldera, the Bloodgood Canyon Tuff (BCT). Extensive mapping by previous workers have provided a limited whole rock geochemical dataset and descriptions of the unit, but a detailed study had not been conducted. I present new whole-rock major- and trace-element analyses, Sr, Nd, and Pb isotope …
Channel Bar Morphology, Distribution, And Mining-Related Geochemistry In The Big River, St. Francois County, Missouri: Implications For Geomorphic Recovery, Lindsay Marie Olson
Channel Bar Morphology, Distribution, And Mining-Related Geochemistry In The Big River, St. Francois County, Missouri: Implications For Geomorphic Recovery, Lindsay Marie Olson
Graduate Theses/Dissertations
Tailings releases associated with large-scale historical Pb mining in St. Francois County, Missouri resulted in system-wide contamination of Pb and excess sediment in the Big River. Previous studies have addressed basin and segment scale variability of the contaminants; however, little is known about reach and bar scale variability. This study addresses how mining sediment inputs influence bar form and geochemistry across a range of scales. Bar sediment samples were collected at 21 reaches and analyzed for particle size and geochemistry, while air photo analysis was used to evaluate channel morphology, bar type, and area. Bar area is initially low in …
Targeting Sav Restoration At Lake Mattamuskeet Using Gis And Landsat 8 Data, Lindsey Shanks
Targeting Sav Restoration At Lake Mattamuskeet Using Gis And Landsat 8 Data, Lindsey Shanks
Theses, Dissertations and Culminating Projects
Lake Mattamuskeet, a large, shallow lake on the coast of North Carolina, has undergone water quality degradation and submerged aquatic vegetation (SAV) decline over recent years. Water depth and water clarity have been established as key drivers of SAV loss. To target locations for the restoration of SAV in the lake, an analysis that focuses on water clarity, water depth, and current SAV presence was developed. Two separate methodologies were conducted and compared to analyze water clarity in the lake. The first applied four years (2013-2016) of Landsat 8 imagery to a previously developed model that predicts water clarity from …