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Articles 481 - 510 of 1124
Full-Text Articles in Earth Sciences
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 …
The Effect Of Micro-Elevation Changes On The Distribution Of Tidal Freshwater Wetland Plant Communities, Thomas Joseph Muratore Jr.
The Effect Of Micro-Elevation Changes On The Distribution Of Tidal Freshwater Wetland Plant Communities, Thomas Joseph Muratore Jr.
Departmental Honors & Graduate Capstone Projects
Vegetation community structures within tidal freshwater wetlands are subject to control by diurnal tides. Elevation affects the degree of inundation of wetland soils and ultimately controls reduction potentials, a stressor placed on wetland plants. Previous studies have not looked at the affect micro elevation changes have on plant community structures. In order to understand the community structures, relative elevation, reduction potential (Eh), reactive nitrogen, and species diversity were recorded. Sites 1 and 2 were identified on the Pamunkey River and variables were recorded every 2.4 meters and 1.5 meters, respectively. There was a positive correlation between elevation and redox potential …
Revealing The Current Relationship Between Stream Acidification And Fish Species Richness: What Is The Status After Two Decades Of Recovery?, Patrick A. Harmon
Revealing The Current Relationship Between Stream Acidification And Fish Species Richness: What Is The Status After Two Decades Of Recovery?, Patrick A. Harmon
Masters Theses, 2010-2019
Prior to limitations placed on atmospheric emission of sulfur dioxide, Shenandoah National Park streams were heavily impacted by acid deposition. Acidification of these streams resulted in a depletion of acid neutralizing capacity (ANC) and a loss of fish species diversity. Differences in bedrock composition of park watersheds produce variation in stream response to acidification such that siliciclastic watersheds provide the lowest ANC, basaltic-carbonate watersheds provide the highest ANC, and granitic watersheds provide an intermediate ANC. Previous results by Bulger et al. (1995) indicated a significant relationship between ANC and fish species richness in thirteen park streams, such that low ANC …
Possible Evaporite Karst In An Interior Layered Deposit In Juventae Chasma, Mars, Davide Baioni, Mario Tramontana
Possible Evaporite Karst In An Interior Layered Deposit In Juventae Chasma, Mars, Davide Baioni, Mario Tramontana
International Journal of Speleology
This paper describes karst landforms observed in an interior layered deposit (ILD) located within Juventae Chasma a trough of the Valles Marineris, a rift system that belongs to the Tharsis region of Mars. The ILD investigated is characterized by spectral signatures of kieserite, an evaporitic mineral present on Earth. A morphologic and morphometric survey of the ILD surface performed on data of the Orbiter High Resolution Imaging Science Experiment (HiRISE) highlighted the presence of depressions of various shapes and sizes. These landforms interpreted as dolines resemble similar karst landforms on Earth and in other regions of Mars. The observed karst …
Mechanistic Modeling Of Insecticide Risks To Breeding Birds In North American Agroecosystems, Matthew Etterson, Kristina Garber, Edward Odenkirchen
Mechanistic Modeling Of Insecticide Risks To Breeding Birds In North American Agroecosystems, Matthew Etterson, Kristina Garber, Edward Odenkirchen
United States Environmental Protection Agency: Publications
Insecticide usage in the United States is ubiquitous in urban, suburban, and rural environments. There is accumulating evidence that insecticides adversely affect non-target wildlife species, including birds, causing mortality, reproductive impairment, and indirect effects through loss of prey base, and the type and magnitude of such effects differs by chemical class, or mode of action. In evaluating data for an insecticide registration application and for registration review, scientists at the United States Environmental Protection Agency (USEPA) assess the fate of the insecticide and the risk the insecticide poses to the environment and non-target wildlife. Current USEPA risk assessments for pesticides …
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 …
The Effects Of Urbanization On Nitrogen Processing In Urban Streams, Peter Francissen, Dr. Kevin Geedey, Dr. Michael Reisner
The Effects Of Urbanization On Nitrogen Processing In Urban Streams, Peter Francissen, Dr. Kevin Geedey, Dr. Michael Reisner
Celebration of Learning
Urban stream syndrome is described as the deterioration of stream health in an urbanized watershed and is associated with the loss of ecosystem services, which in turn degrades downstream environments. One key symptom of the urban stream syndrome is reduced processing of inorganic nitrogen. Previous research suggests that as urbanization increases and water quality decreases, the uptake length (Sw) of inorganic N increases. This indicates that the stream is increasing the export of N downstream compared to in situ incorporation of N into the ecosystem. We measured uptake length (Sw) of NO3, using a pulse addition method, along 9 different …
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 …
A Spatial Relationship Between Stream Slope Stability And Water Quality Within An Urban Watershed In Rock Island, Il, Joseph Teresi
A Spatial Relationship Between Stream Slope Stability And Water Quality Within An Urban Watershed In Rock Island, Il, Joseph Teresi
Celebration of Learning
The consistently observed phenomenon of highly altered streams and degraded water quality draining urban areas across the U.S is described as the urban stream syndrome. Rock Island, Illinois, contains a population of nearly 39,000 people, and houses industrial and logistical businesses amidst a city of aging infrastructure. Streams occupy ravines that have incised into the Quaternary loess plateau, flowing south towards the Rock River and north or west towards the Mississippi River. In an attempt to understand better the severity of Rock Island’s urban stream syndrome, this project analyzed stream slopes within the Rock Island watershed to categorize their level …
Elemental Contamination Of An Ancient Copper Mine In Killarney, Ireland, Courtney Chouinard
Elemental Contamination Of An Ancient Copper Mine In Killarney, Ireland, Courtney Chouinard
Celebration of Learning
Ross Island Copper Mine, located in Killarney National Park, Killarney, Ireland, is known for archeological artifacts of copper from the Bronze Age. Copper production surged in the late 1700s and into the mid-1800s. The mine included both open pits (e.g. Blue Hole) and underground excavations (e.g. Western Mine). Copper veins were found in the Mississippian-aged limestone bedrock along with chalcopyrite and tennantite ore. In 1912, tourism had become the main source of income in the area, and the mines and the land surrounding them were remediated and became a part of the national park. Mine shafts were filled in, waste …
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 …
Dendrochronological Analysis Of Historical Structures In Southwestern Ohio Dewitt House Oxford, Ohio.
Historic Structures
Dating historical structures in Oxford Ohio using dendrochronology. The Historical Structures collection consists of reports that are the result of dendochronological analysis of timbers from structures in Pennsylvania and Ohio. Contributors: Fetters, Caitlin; Krivicich, Mike; Lehmann, Sophie; Wiles, Greg
Concentrations And Size Distributions Of Bacteria-Containing Particles Over Oceans From China To The Arctic Ocean, Ming Li, Xiawei Yu, Hui Kang, Zhouqing Xie, Pengfei Zhang
Concentrations And Size Distributions Of Bacteria-Containing Particles Over Oceans From China To The Arctic Ocean, Ming Li, Xiawei Yu, Hui Kang, Zhouqing Xie, Pengfei Zhang
Publications and Research
During the third China Arctic Research Expedition (July–September 2008), size-resolved measurements of bacteria-containing particles (BCPs) in the marine boundary layer (MBL) air were conducted during a cruise through the East China Sea, the Yellow Sea, the Japan Sea, the Okhotsk Sea, the Bering Sea, the Chukchi Sea, and the Arctic Ocean. The concentrations of total airborne BCPs (TBCPs), non-salt tolerant airborne BCPs (NSBCPs), and salt tolerant airborne BCPs (SBCPs) varied from 29 to 955 CFU m − 3 (CFU = Colony Forming Unit), 16 to 919 CFU m − 3 , and 4 to 276 CFU m − 3 , …
Lithology And Depositional Environments Of A Portion Of The Clays Ferry Formation (Middle And Upper Ordovician) Exposed At Silver Creek, Madison County, Kentucky, Autumn Murray
EKU Faculty and Staff Scholarship
We measure, describe, and interpret a carbonate stratigraphic section within the Clays Ferry Formation (Middle and Upper Ordovician) cropping out in Madison County, Kentucky (USGS Kirksville 7.5” quadrangle). The total thickness of the measured section is 4.76 m. We sampled the stratigraphic section at approximately half-meter intervals, also taking samples at lithology changes. We collected a total 20 samples, all of which were slabbed, and then selected 12 samples for thin section analysis.
Observed lithologies represent discrete depositional environments. The rocks are dominantly limestones with some carbonate shales deposited in shallow-water depositional environments that are generally open-marine, subtidal with perhaps …
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.
Bridging The Gap Between The Foreland And Hinterland Ii: Geochronology And Tectonic Setting Of Ordovician Magmatism And Basin Formation On The Laurentian Margin Of New England And Newfoundland, Francis A. Macdonald, Paul M. Karabinos, James L. Crowley, Eben B. Hodgin, Peter W. Crockford, John W. Delano
Bridging The Gap Between The Foreland And Hinterland Ii: Geochronology And Tectonic Setting Of Ordovician Magmatism And Basin Formation On The Laurentian Margin Of New England And Newfoundland, Francis A. Macdonald, Paul M. Karabinos, James L. Crowley, Eben B. Hodgin, Peter W. Crockford, John W. Delano
Geosciences Faculty Publications and Presentations
Ordovician strata of the Mohawk Valley and Taconic allochthon of New York and the Humber margin of Newfoundland record multiple magmatic and basin-forming episodes associated with the Taconic orogeny. Here we present new U-Pb zircon geochronology and whole rock geochemistry and neodymium isotopes from Early Paleozoic volcanic ashes and siliciclastic units on the northern Appalachian margin of Laurentia. Volcanic ashes in the Table Point Formation of Newfoundland and the Indian River Formation of the Taconic allochthon in New York yield dates between 466.16 ± 0.12 and 464.20 ± 0.13 Ma. Red, bioturbated slate of the Indian River Formation record a …
Bridging The Gap Between The Foreland And Hinterland I: Geochronology And Plate Tectonic Geometry Of Ordovician Magmatism And Terrane Accretion On The Laurentian Margin Of New England, Paul M. Karabinos, Francis A. Macdonald, James L. Crowley
Bridging The Gap Between The Foreland And Hinterland I: Geochronology And Plate Tectonic Geometry Of Ordovician Magmatism And Terrane Accretion On The Laurentian Margin Of New England, Paul M. Karabinos, Francis A. Macdonald, James L. Crowley
Geosciences Faculty Publications and Presentations
U-Pb dates on magmatic and detrital zircon from samples in the hinterland of the Taconic orogen place new constraints on the timing and plate tectonic geometry of terrane accretion and magmatic arc activity. The Moretown terrane, a Gondwanan-derived exotic block, extends from the Rowe Schist-Moretown Formation contact in the west to the Bronson Hill arc in the east. Arc-related plutonic and volcanic rocks formed above an east-dipping subduction zone under the western leading edge of the Moretown terrane from approximately 500 to 475 Ma, until collision with hyperextended distal fragments of Laurentia, represented by the Rowe Schist, at 475 Ma. …
Soil Science Lesson Plan For The Cal Poly Learn By Doing Lab, Kelsey Ormonde
Soil Science Lesson Plan For The Cal Poly Learn By Doing Lab, Kelsey Ormonde
Natural Resources Management and Environmental Sciences
To increase interest in soil science and other related sciences, educational materials need to be tailored to appeal to younger students. The purpose of this project was to create a soil science lesson plan that could be utilized by the Cal Poly Learn By Doing Lab. Information from several articles, textbooks, lesson plans, and websites was reviewed to create a soil science lesson plan for students in 5-8th grade. The lesson plan focused on the three sub-disciplines of soil science; physical, chemical, and biological. Activities were created to correspond to the three sub-disciplines. Alternate activities were created to allow …
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 …
Magmatic Hydrothermal Alteration And Secondary Post-Shock Features In Martian Olivine-Phyric Basalt Northwest Africa 10416; Petrology And Geochemistry Of Primitive Achondrite Northwest Africa 11042, Zoltan Vaci
Earth and Planetary Sciences ETDs
The Martian olivine-phyric basalt Northwest Africa (NWA) 10416 contains large olivine xenocrysts whose cores have been stained brown by hydrothermal alteration and whose rims are composed of pristine olivine overgrowths. Microanalysis of these olivine cores reveals various degrees of amorphization, some of which have been overprinted by terrestrial weathering, evident as part of a weathering rind along the exposed surface of the meteorite. Studies of a completely unweathered terrestrial analogue basalt from southern Colorado reveal similar features and indicate that both basalts were altered in a supersolidus magma chamber setting. The alteration features in NWA 10416 thus imply the presence …
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 …
Nano-Petrophysics Of The Hybrid Shale-Oil Bone Spring Formation, Lea County, New Mexico, Jordan Bevers
Nano-Petrophysics Of The Hybrid Shale-Oil Bone Spring Formation, Lea County, New Mexico, Jordan Bevers
Earth & Environmental Sciences Theses - Archive
Despite the increased hydrocarbon production in hydraulically stimulated unconventional reservoirs, how fluid flows through the rock matrix in these reservoirs is still not well understood. It has been shown that much of the porosity in unconventional mudrocks is nanometer in size, making research challenging as analyzing these pores requires specialized methodologies. These pore networks affect fluid flow by their pore sizes, pore throats, and topology (pore connectivity). The Bone Spring Formation is one of the fastest growing unconventional plays in the world. It is a hybrid shale-oil system with high total organic carbon (TOC) source rocks juxtaposed against organic-lean reservoir …
Petrophysical Properties Of The Yeso, Abo And Cisco Formations In The Permian Basin In New Mexico, U.S.A., Griffin Mann
Petrophysical Properties Of The Yeso, Abo And Cisco Formations In The Permian Basin In New Mexico, U.S.A., Griffin Mann
Earth & Environmental Sciences Theses - Archive
The area that comprises the Northwest Shelf in Lea Co., New Mexico has been heavily drilled over the past half century. The main target being shallow reservoirs within the Permian section (San Andres and Grayburg Formations). With a focus shifting towards deeper horizons, there is a need for more petrophysical data pertaining to these formations, which is the focus of this study through a variety of techniques. This study involves the use of contact angle measurements, fluid imbibition tests, Mercury Injection Capillary Pressure (MICP) and log analysis to evaluate the nano-petrophysical properties of the Yeso, Abo and Cisco Formation within …
A Megabreccia With Associated Stratigraphy Of The Cherry Canyon And Bell Canyon Formations Transition (Guadalupian, Middle Permian), Southern Delaware Mountains, West Texas, Johnathon Lee Bogacz
A Megabreccia With Associated Stratigraphy Of The Cherry Canyon And Bell Canyon Formations Transition (Guadalupian, Middle Permian), Southern Delaware Mountains, West Texas, Johnathon Lee Bogacz
Earth & Environmental Sciences Theses - Archive
The Cherry Canyon and Bell Canyon Formations (Guadalupian, Middle Permian) are well exposed in the southern part of the Delaware Mountains, West Texas and are marked by the presence of several distinct and widespread debris flows. Various lithostratigraphic units (members) of these two formations were originally named for exposures in the Guadalupe Mountains and the northern part of the Delaware Mountains, West Texas. These units are not easily recognized litho-stratigraphically in the southern part of the Delaware Mountains, but some correlations can be made by using biostratigraphic methods. One of the easily recognizable debris flows in the southern Delaware Mountains …
Petrography And Geochemistry Of Continental Carbonates In South Texas: Implications For Oligocene-Miocene Paleoclimate And Paleoenvironment Near Sea Level, Conan Ray Godfrey
Petrography And Geochemistry Of Continental Carbonates In South Texas: Implications For Oligocene-Miocene Paleoclimate And Paleoenvironment Near Sea Level, Conan Ray Godfrey
Earth & Environmental Sciences Theses - Archive
The Oligocene-Miocene Catahoula, Oakville, and Goliad formations in south Texas contain abundant continental carbonates which are useful in reconstructing paleoclimate and paleoenvironment in a near sea level region. Field observations and thin section characterizations identify three types of pedogenic carbonates, including rhizoliths, carbonate nodules, and platy horizons, and two types of groundwater carbonates, including cemented beds and carbonate concretions. The pedogenic carbonates display sharp upper contacts and diffuse lower contacts, and contain soil structural elements and biogenic elements related to root action. Under microscope, the pedogenic carbonates are micritic with clotted micrite, micrite laminations, and alveolar-septal structures and display dull …
(Uranium-Thorium)/Helium Thermochronologic Constraints On Secondary Iron-Oxide Mineralization In Southwestern New Mexico, Michael Channer
(Uranium-Thorium)/Helium Thermochronologic Constraints On Secondary Iron-Oxide Mineralization In Southwestern New Mexico, Michael Channer
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Southwestern New Mexico experienced protracted volcanism from ~60 Ma to 500 ka and associated epithermal mineralization. We apply hematite (U-Th)/He (hematite He) thermochronology to fracture-hosted hematite in the Lordsburg Mining District to resolve the timing of mineralization related to hydrothermal fluid circulation. We interpret hematite He dates with integrated field and structural observations, scanning electron microscopy to characterize hematite texture and grain size distribution, and zircon U-Pb and zircon (U-Th)/He (zircon He) chronology to constrain the timing of host rock formation and the ambient low-temperature thermal history, respectively. Undeformed hematite fills fractures cut a brecciated rhyolite and preserve open voids. …
Magmatic Evolution Of Early Subduction Zones: Geochemical Modeling And Chemical Stratigraphy Of Boninite And Fore Arc Basalt From The Bonin Fore Arc, Emily A. Haugen
Magmatic Evolution Of Early Subduction Zones: Geochemical Modeling And Chemical Stratigraphy Of Boninite And Fore Arc Basalt From The Bonin Fore Arc, Emily A. Haugen
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The Izu-Bonin-Mariana arc stretches south from Japan to Guam in the Western Pacific. International Ocean Discovery Project Expedition 352 drilled four core in the fore arc of the Izu-Bonin arc east of the Bonin Islands: U1439C, U1440B, U1441A, and U1442A. From the four core, 124 samples were retrieved and analyzed for major and trace elements. Two main rock types were identified: FAB and boninite. FAB is a Mid-Ocean Ridge Basalt (MORB)-like tholeiite with variable fluid mobile element enrichment such as Rb, Ba, and Sr, and low Ti/V ratios more similar to an island arc volcanic than a mid-ocean ridge volcanic. …
A Stochastic Model For Water-Vegetation Systems And The Effect Of Decreasing Precipitation On Semi-Arid Environments, Shannon A. Dixon
A Stochastic Model For Water-Vegetation Systems And The Effect Of Decreasing Precipitation On Semi-Arid Environments, Shannon A. Dixon
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Current climate change trends are affecting the magnitude and recurrence of extreme weather events. In particular, several semi-arid regions around the planet are confronting more intense and prolonged lack of precipitation, slowly transforming these regions into deserts. Many mathematical models have been developed for purposes of analyzing vegetation-water interactions, particularly in semi-arid landscapes. Most models are based on the average behavior of the system as a whole, and how it is influenced by external changes. These models may be termed "macro-scale" models. Other models have concerned themselves with the interactions between individuals, in this case the interactions between individual plants …
Sclerocactus Wetlandicus: Habitat Characterization, Seed Germination And Mycorrhizal Analysis, Kourtney T. Harding
Sclerocactus Wetlandicus: Habitat Characterization, Seed Germination And Mycorrhizal Analysis, Kourtney T. Harding
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The Uinta Basin hookless cactus (Sclerocactus wetlandicus) is a threatened species native to Eastern Utah. The cactus is found in a landscape highly disturbed by non-renewable energy production. To understand the environmental conditions that support natural growth of this cactus, we asked what types of plants were present in the same areas as the cactus, and if the types of plants were different in environments that were disturbed. From our assessment, we determined that the types of plants present in disturbed areas were drastically different from those present in undisturbed locations. Areas previously used for energy production are …