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2019

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Spatial And Temporal Distribution Of Hydrothermal Minerals And Sources Of Hydrothermal Fluids Inferred From Light Stable Isotopes, Keweenaw Peninsula Native Copper District, Michigan, Thomas Bodden Jan 2019

Spatial And Temporal Distribution Of Hydrothermal Minerals And Sources Of Hydrothermal Fluids Inferred From Light Stable Isotopes, Keweenaw Peninsula Native Copper District, Michigan, Thomas Bodden

Dissertations, Master's Theses and Master's Reports

Hydrothermal native copper deposits are hosted by Mesoproterozoic Midcontinent Rift-filling volcanic and sedimentary rocks in Michigan’s Keweenaw Peninsula. The genesis of the native copper deposits has been a point of interest since their discovery. Native copper and associated mineral assemblages vary temporally and spatially. A refined mineral paragenesis is presented and used as the basis to spatially compare mineral assemblages as it is essential that spatial comparison involve only minerals that are temporally/genetically, related to each other. The main-stage minerals associated with precipitation of native copper are spatially zoned. The higher-grade zones correspond to the area of native copper deposits …


Assessing The Spatial And Temporal Variability Of The Detroit River And Harmful Algal Blooms In Western Lake Erie, Angela W. Yu Jan 2019

Assessing The Spatial And Temporal Variability Of The Detroit River And Harmful Algal Blooms In Western Lake Erie, Angela W. Yu

Dissertations, Master's Theses and Master's Reports

Despite efforts to reduce the occurrence of harmful algal blooms (HABs) in western Lake Erie, blooms recur annually due to agricultural runoff, storms with high winds and heavy rains, and weak lake circulation patterns. The influence from river inputs on the spatial and temporal characteristics of HABs remains relatively unknown. The Detroit River, which contributes about 80% of the basin's total inflow can have a large influence on the spatial and temporal distribution of the bloom. To understand this, optically classified imagery, in situ water measurements, and meteorological and river discharge observations were compiled and synthesized to examine the spatiotemporal …


Biogeochemical Response To Vegetation And Hydrologic Change In An Alaskan Boreal Fen Ecosystem, Danielle L. Rupp Jan 2019

Biogeochemical Response To Vegetation And Hydrologic Change In An Alaskan Boreal Fen Ecosystem, Danielle L. Rupp

Dissertations, Master's Theses and Master's Reports

Boreal peatlands store approximately one third of the earth’s terrestrial carbon, locked away in currently waterlogged and frozen conditions. Peatlands of boreal and arctic ecosystems are affected increasingly by shifting hydrology caused by climate change. The consequences of these relatively rapid ecosystem changes on carbon cycling between the landscape and the atmosphere could provide an amplifying feedback to climate warming. Alternatively, the advancement of terrestrial vegetation into once waterlogged soils could uptake carbon as a sink. Previous work suggests that fens will become an increasingly dominant landscape feature in the boreal. However, studies investigating fens, their response to hydrologic and …


Influence Of Ligand Complexation On Nickel Toxicity, Speciation And Bioavailability In Marine Waters, Samantha Sherman Jan 2019

Influence Of Ligand Complexation On Nickel Toxicity, Speciation And Bioavailability In Marine Waters, Samantha Sherman

Theses and Dissertations (Comprehensive)

Currently there are no site-specific bioavailability-based prediction models for assessing the impacts of nickel (Ni) in marine environments although there are indications that these may be warranted. The aim of this research was to characterize the complexation of Ni in relation to toxicity and speciation. Various complexing ligands were used, and it was predicted that the binding affinity (logKf) of ligands would be inversely correlated to toxicity based on dissolved Ni concentrations ([NiD]) but that on a free ion concentration ([Ni2+]) basis, toxicity would not vary. A two-phased approach was used; the first was a proof of principle where synthetic …


Influence Of Land Cover And Soil Moisture Based Brown Ocean Effect On An Extreme Rainfall Event From A Louisiana Gulf Coast Tropical System, Udaysankar S. Nair, Eric Rappin, Emily Foshee, Warren Smith, Roger A. Pielke Sr., Rezaul Mahmood, Jonathan L. Case, Clay B. Blankenship, Marshall Shepherd, Joseph A. Santanello, Dev Niyogi Jan 2019

Influence Of Land Cover And Soil Moisture Based Brown Ocean Effect On An Extreme Rainfall Event From A Louisiana Gulf Coast Tropical System, Udaysankar S. Nair, Eric Rappin, Emily Foshee, Warren Smith, Roger A. Pielke Sr., Rezaul Mahmood, Jonathan L. Case, Clay B. Blankenship, Marshall Shepherd, Joseph A. Santanello, Dev Niyogi

High Plains Regional Climate Center: Personnel Publications

Extreme flooding over southern Louisiana in mid-August of 2016 resulted from an unusual tropical low that formed and intensified over land. We used numerical experiments to highlight the role of the ‘Brown Ocean’ effect (where saturated soils function similar to a warm ocean surface) on intensification and it’s modulation by land cover change. A numerical modeling experiment that successfully captured the flood event (control) was modified to alter moisture availability by converting wetlands to open water, wet croplands, and dry croplands. Storm evolution in the control experiment with wet antecedent soils most resembles tropical lows that form and intensify over …


The Total Solar Eclipse Of 2017: Meteorological Observations From A Statewide Mesonet And Atmospheric Profiling Systems, Rezaul Mahmood, Megan Schargorodski, Eric Rappin, Melissa Griffin, Patrick Collins, Kevin Knupp, Andrew Quilligan, Ryan Wade, Kevin Cary, Stuart Foster Jan 2019

The Total Solar Eclipse Of 2017: Meteorological Observations From A Statewide Mesonet And Atmospheric Profiling Systems, Rezaul Mahmood, Megan Schargorodski, Eric Rappin, Melissa Griffin, Patrick Collins, Kevin Knupp, Andrew Quilligan, Ryan Wade, Kevin Cary, Stuart Foster

High Plains Regional Climate Center: Personnel Publications

A total solar eclipse traversed 37 the continental United States on August 21, 2017. It 38 was the first such event in 99 years and provided a rare opportunity to observe the atmospheric response from a variety of instrumented observational platforms. This paper discusses the high quality observations collected by the Kentucky Mesonet (www.kymesonet.org), a research-grade meteorological and climatological observation network consisting of 72 stations and measuring air temperature, precipitation, relative humidity, solar radiation, wind speed, and wind direction. The network samples the atmosphere, for most variables, every three seconds and then calculates and records observations every five minutes. During …


Irrigation Impacts On Minimum And Maximum Surface Moist Enthalpy In The Central Great Plains Of The Usa, Tianyi Zhang, Rezaul Mahmood, Xiaomao Lin, Roger A. Pielke Sr. Jan 2019

Irrigation Impacts On Minimum And Maximum Surface Moist Enthalpy In The Central Great Plains Of The Usa, Tianyi Zhang, Rezaul Mahmood, Xiaomao Lin, Roger A. Pielke Sr.

High Plains Regional Climate Center: Personnel Publications

Agricultural activities notably alter weather and climate including near-surface heat content. However, past research primarily focused on dry bulb temperature without considering the role of water vapor (dew point temperature) on surface air heat content. When using dry bulb temperature trends to assess these changes, for example, not including concurrent trends in absolute humidity can lead to errors in the actual rate of warming or cooling. Here we examined minimum and maximum surface moist enthalpy, which can be expressed as “equivalent temperature.” Using hourly climate data in the Central Great Plains (Nebraska and Kansas) from 1990 to 2014, the averages …


Enhancing Acis Maps: Increasing Usability Through A Gis Portal, Natalie Umphlett, Warren Pettee, Bill Sorensen, Crystal J. Stiles Jan 2019

Enhancing Acis Maps: Increasing Usability Through A Gis Portal, Natalie Umphlett, Warren Pettee, Bill Sorensen, Crystal J. Stiles

High Plains Regional Climate Center: Personnel Publications

The High Plains Regional Climate Center (HPRCC) is one of six NOAA Regional Climate Centers (RCCs) in the United States that aims to provide timely climate data and information to the public for cost-effective decision-making. As part of a three-tiered approach to climate services, the RCCs address needs on the national, regional, state, and local scales for a variety of sectors including agriculture, energy, natural resource management, research, transportation, and water resources. Working together, the RCCs develop and disseminate a wide range of valueadded climate products and services.

One of the HPRCC’s most popular products is the Applied Climate Information …


Conducting A Drought-Specific Thira (Threat And Hazard Identification And Risk Assessment): A Powerful Tool For Integrating All-Hazard Mitigation And Drought Planning Efforts To Increase Drought Mitigation Quality, Elliot Wickham, Deborah J. Bathke, Tarik Abdel-Monem, Tonya K. Bernadt, Denise Bulling, Lisa M. Pytlikzillig, Crystal J. Stiles, Nicole Wall Jan 2019

Conducting A Drought-Specific Thira (Threat And Hazard Identification And Risk Assessment): A Powerful Tool For Integrating All-Hazard Mitigation And Drought Planning Efforts To Increase Drought Mitigation Quality, Elliot Wickham, Deborah J. Bathke, Tarik Abdel-Monem, Tonya K. Bernadt, Denise Bulling, Lisa M. Pytlikzillig, Crystal J. Stiles, Nicole Wall

High Plains Regional Climate Center: Personnel Publications

In the United States, drought is the second costliest natural disaster, which leads to the need for increased drought mitigation efforts over time. However, drought planning has lagged behind other hazard mitigation efforts, which is likely due to the lack of a national drought planning policy. Although the Federal Emergency Management Agency (FEMA) requires all jurisdictions have a hazard mitigation plan (HMP) to receive pre-disaster mitigation funds, drought has only recently been a requirement in HMPs. In 2012, Nebraska witnessed its worse drought in recent history, which exposed the gaps in drought planning effectiveness at all jurisdictional levels. To address …


Role Of Sea Surface Temperatures In Forcing Circulation Anomalies Driving U.S. Great Plains Pluvial Years, Paul X. Flanagan, Jeffrey B. Basara, Jason C. Furtado, Elinor R. Martin, Xiangming Xiao Jan 2019

Role Of Sea Surface Temperatures In Forcing Circulation Anomalies Driving U.S. Great Plains Pluvial Years, Paul X. Flanagan, Jeffrey B. Basara, Jason C. Furtado, Elinor R. Martin, Xiangming Xiao

High Plains Regional Climate Center: Personnel Publications

In the U.S. Great Plains (GP), diagnosing precipitation variability is key in developing an understanding of the present and future availability of water in the region. Building on previous work investigating U.S. GP pluvial years, this study usesERAtwentieth century (ERA-20C) reanalysis data to investigate key circulation anomalies driving GP precipitation anomalies during a subset of GP pluvial years (called in this paper Pattern pluvial years). With previous research showing links between tropical Pacific sea surface temperature (SST) anomalies and GP climate variability, this study diagnoses the key circulation anomalies through an analysis of SSTs and their influence on the atmosphere. …


Quantifying The Magnitude And Spatial Variability Of Bedrock Erosion Beneath The Sisters Glacier, Washington, Using Cosmogenic 3he Concentrations, Sarah W. Francis Jan 2019

Quantifying The Magnitude And Spatial Variability Of Bedrock Erosion Beneath The Sisters Glacier, Washington, Using Cosmogenic 3he Concentrations, Sarah W. Francis

WWU Graduate School Collection

Cosmogenic 3He analyses provide a tool to infer spatial variation of cirque-glacial bedrock erosion. 3He accumulates in bedrock exposed at the surface as a result of cosmic ray bombardment; the concentration of cosmogenic 3He increases with exposure time as well as proximity to the surface. The Twin Sisters range, North Cascades, WA is an ideal location to use cosmogenic 3He to infer cirque-glacial erosion depths and rates, due to the dunite bedrock and the detailed record of Holocene glaciation from the nearby Mount Baker. We used field mapping, lidar data and aerial imagery to identify bedrock …


Increased Hydrologic Variability Near The Paleocene-Eocene Boundary (Piceance Creek Basin, Colorado, U.S.A.)), Anna Lesko Jan 2019

Increased Hydrologic Variability Near The Paleocene-Eocene Boundary (Piceance Creek Basin, Colorado, U.S.A.)), Anna Lesko

WWU Graduate School Collection

The Paleocene Eocene Thermal Maximum (PETM) was a rapid global warming event that occurred approximately 56 million years ago and represents the largest and most abrupt warming event of the Cenozoic Era. The PETM caused mean annual temperatures to increase at least 5°C globally above the already warm, greenhouse climate state of the early Paleogene. The warming and associated perturbation of the carbon cycle had numerous consequences for paleoenvironments and paleobiologic systems. This study investigates the hydrologic response to the PETM within the interior of North America and presents a new d13C bulk organic record. This study generates …


Clinopyroxene Trace Element Chemistry As A Proxy For Magma Compositional Variations In The Izu Bonin Rear Arc Over The Last 15 Million Years, Kimberly N. (Kimberly Nicole) Wurth Jan 2019

Clinopyroxene Trace Element Chemistry As A Proxy For Magma Compositional Variations In The Izu Bonin Rear Arc Over The Last 15 Million Years, Kimberly N. (Kimberly Nicole) Wurth

WWU Graduate School Collection

This study presents major and trace element chemistry of clinopyroxene (CPX) in 0-15 Ma core material recovered from Site U1437 during IODP Expedition 350. Because no fresh glass is present in the core samples older than 4.4 Ma, and hence there is no way to directly determine magma compositions, my study presents the development of a novel method for calculating liquid compositions from CPX grains in volcaniclastic sediments using distribution coefficients and trace elements measured in CPX.

Geochemical data from CPX grains was acquired using a laser ablation-inductively coupled plasma-mass spectrometer (LA-ICP-MS). These data were used to calculate trace element …


Assessing Coastal Vulnerability To Storm Surge And Wave Impacts With Projected Sea Level Rise Within The Salish Sea, Nathan R. Vanarendonk Jan 2019

Assessing Coastal Vulnerability To Storm Surge And Wave Impacts With Projected Sea Level Rise Within The Salish Sea, Nathan R. Vanarendonk

WWU Graduate School Collection

Sea level rise (SLR) in the Salish Sea, a large inland waterway shared between Canada and the United States, is expected to be 0.3 to 1.8 m by the year 2100. Uncertainty in greenhouse gas emissions, global ice sheet loss, and other controls such as vertical land movement all contribute to this range. Valuable property, infrastructure, and critical habitats for shellfish and threatened salmon populations are at risk to coastal changes associated with SLR. Additionally, development in Washington State is expected to accelerate through the end of the 21st century adding extra pressure on protecting ecosystems and people from natural …


Slip And Strain Accumulation Along The Sadie Creek Fault, Olympic Peninsula, Washington, Cody Duckworth Jan 2019

Slip And Strain Accumulation Along The Sadie Creek Fault, Olympic Peninsula, Washington, Cody Duckworth

WWU Graduate School Collection

Upper-plate faulting in the Olympic Peninsula of Washington State reflects the interaction of crustal blocks within the Cascadia forearc as well as contributions from various earthquake cycle processes along the Cascadia subduction zone (CSZ). These processes include interseismic coupling, megathrust earthquakes, and aseismic slow slip events. In this study I utilize high resolution airborne lidar, field mapping of deformed surficial deposits and landforms, optically stimulated luminescence (OSL) dating and radiocarbon dating to reconstruct fault slip rates since Late Pleistocene deglaciation on the Sadie Creek fault (SCF), located north of the Olympic Mountains. This mapping reveals the SCF as a ~14 …


Photometric Investigations Of Weathering Rinds And Coatings With Implications For Mars, Kathleen Hoza Jan 2019

Photometric Investigations Of Weathering Rinds And Coatings With Implications For Mars, Kathleen Hoza

WWU Graduate School Collection

Reflectance spectroscopy is a major technique for characterizing the composition of planetary surfaces, and has led to many key findings in planetary geology. In laboratory measurements, reflectance spectrometers typically acquire data using a standard, fixed viewing geometry. Measurements from spacecraft, however, may be acquired at a wide range of viewing geometries, depending on the orientation of the instrument relative to the target surface and the Sun. For many materials, the impact of viewing geometry on reflectance is minor; however, some materials’ spectral signatures can be influenced by these photometric effects. In particular, spectra of weathering rinds and rock coatings are …


Cosmic Ray Sensors For The Continuous Measurement Of Arctic Snow Accumulation And Melt, Anton Jitnikovitch Jan 2019

Cosmic Ray Sensors For The Continuous Measurement Of Arctic Snow Accumulation And Melt, Anton Jitnikovitch

Theses and Dissertations (Comprehensive)

In the Arctic, winter persists for much of the year, resulting in a hydrological system that is primarily regulated by snow and snowmelt runoff, and has important implications on vegetation, animals, and on the thermal regime of the active layer and permafrost. Snow water equivalent (SWE) measurements such as remote sensing techniques provide coarse resolution data, while snow surveys and snow-pits are labour intensive, have limited spatial coverage and do not provide a continuous reading. Over the last few decades, cosmic ray sensors (CRS) have been proposed as a way to provide much improved snow data, but few studies have …


Use Of Pre-Industrial Baselines To Assess Sources And Pathways Of Metals In Surface Sediment Of Floodplain Lakes In The Peace-Athabasca Delta (Alberta, Canada), Tanner Owca Jan 2019

Use Of Pre-Industrial Baselines To Assess Sources And Pathways Of Metals In Surface Sediment Of Floodplain Lakes In The Peace-Athabasca Delta (Alberta, Canada), Tanner Owca

Theses and Dissertations (Comprehensive)

The effects of natural resources exploitation in northern Canada on downstream aquatic ecosystems is a concern. Assessing these effects requires comprehensive monitoring practices to better inform stakeholders and environmental stewardship decisions. Here, a monitoring approach is developed and applied to assess metals concentrations in lake surface sediments of the Peace-Athabasca Delta (PAD), northern Alberta, Canada. Since the ecological integrity of the PAD is strongly tied to river floodwaters that are critical for replenishing the delta, and the PAD is located downstream of the Alberta oil sands, concerns have been raised over the potential transport of metal contaminants to the PAD …


Correlation Between Mehlich-3 And Ammonium Acetate Extractable Potassium In Kansas Soils, B. Rutter, D. A. Ruiz Diaz Jan 2019

Correlation Between Mehlich-3 And Ammonium Acetate Extractable Potassium In Kansas Soils, B. Rutter, D. A. Ruiz Diaz

Kansas Agricultural Experiment Station Research Reports

The K-State Research and Extension Soil Testing Laboratory has been using Mehlich-3 soil test procedures for phosphorus (P) extraction, and ammonium acetate extraction for potassium (K). Previous research in other states has shown a strong correlation between these two tests for K, but data correlating the two in Kansas soils have been limited. A study was performed on soils from across the state to investigate the relationship between these two methods. A strong positive correlation was observed (r = 0.99) across the wide range of soil types, pH, and fertility conditions represented in the sample set. Linear regression suggests a …


Automatic Detection And Analysis Of Rip Currents At Haeundae Beach Using X-Band Marine Radar, Chanyeong Oh, Kyungmo Ahn, Se-Hyeon Cheon Jan 2019

Automatic Detection And Analysis Of Rip Currents At Haeundae Beach Using X-Band Marine Radar, Chanyeong Oh, Kyungmo Ahn, Se-Hyeon Cheon

OES Faculty Publications

The observation system has been developed to investigate the rip currents at Haeundae beach using Xband marine radar. X-band radar system can observe shape, size, and velocity of rip currents, which is difficult to obtain through field observation by conventional device. Algorithms which automatically detect locations, shapes, and magnitudes of rip currents were developed using time averaged X-band radar sea clutter images. X-band sea clutter images are transformed through 3D FFT into 2D wave number spectrum and frequency spectrum. Rip current velocities were estimated using differences in wave-number spectra and wave frequency spectra due to Doppler shift. The algorithm was …


Utilizing Lipid Biomarkers To Understand The Microbial Community Structure Of Deep Subsurface Black Shale Formations, Rawlings Akondi Jan 2019

Utilizing Lipid Biomarkers To Understand The Microbial Community Structure Of Deep Subsurface Black Shale Formations, Rawlings Akondi

Graduate Theses, Dissertations, and Problem Reports

The deep subsurface environment has been known to host microbes as early as 1926 and has also been suggested to potentially account for as much as 50% of the Earth`s biomass. Researchers have shown that microbes alter their membrane lipid components in response to physiological stress, producing stress indicative lipid biomarkers. However, little effort has been made to understand the subsurface microbial community of the shale ecosystem which is increasingly being exploited and altered by addition of drilling and hydraulic fluids to meet our growing energy needs. Phospholipid fatty acids (PLFAs) are microbial lipid biomarkers and are found in all …


Modeling The Effects Of Climate Variability On Hydrology And Stream Temperatures In The North Fork Of The Stillaguamish River, Kyra Freeman Jan 2019

Modeling The Effects Of Climate Variability On Hydrology And Stream Temperatures In The North Fork Of The Stillaguamish River, Kyra Freeman

WWU Graduate School Collection

The Stillaguamish River in northwest Washington State, USA, provides water resources to local agriculture, industry and First Nations Tribes, and provides crucial habitat for several endangered species of salmonids. The watershed experiences a mild maritime climate and high relief, with rain and snowmelt dominating the streamflow. In anticipation of shifts in snowpack, streamflow, and stream temperature, I use projected global climate scenarios and numerical models to examine future climatic variability on streamflow and stream temperatures in the snow-melt dominated North Fork of the Stillaguamish River. I calibrated the physically based Distributed Hydrology Soil Vegetation Model (DHSVM) and River Basin Model …


Seismic Structure Of Tanaga Island, Alaska, Kevin F. (Kevin Francis) Lally Jan 2019

Seismic Structure Of Tanaga Island, Alaska, Kevin F. (Kevin Francis) Lally

WWU Graduate School Collection

Tanaga Island is located in the Central Aleutian Islands and includes four stratovolcanoes: Sajaka, Tanaga, and East Tanaga in the northwest, and Takawangha in the central part of the island. Of these volcanoes, only Tanaga has a record of historical eruptive activity (in 1914). Over 3,000 earthquakes have been recorded beneath the island and the surrounding offshore region since the six-station seismic network was emplaced in 2003. The origin of these earthquakes is not completely understood, and to arrive at this understanding, more accurate hypocenter locations and power spectra need to be determined. A better analyses including improved locations of …


Paleomagnetic Results From Upper Triassic And Middle Jurassic Strata Of East-Central New Mexico, And Implication For North American Apwp, Masoud Mirzaei Souzani Jan 2019

Paleomagnetic Results From Upper Triassic And Middle Jurassic Strata Of East-Central New Mexico, And Implication For North American Apwp, Masoud Mirzaei Souzani

WWU Graduate School Collection

Two contradictory apparent polar wander paths (APWPs) of North America (NA) for most of Jurassic time have been the subject of many studies since the 1990s, and are important to rectify if in order to constrain the tectonic evolution of the continent. Among various efforts to resolve this persistent issue, additional results from well-dated kimberlite volcanics have been used to support a higher-latitude APWP (Kent et al., 2015), and the controversy was blamed on inclination error (IE) in paleomagnetic results of sedimentary units, most of which are from the U.S. South Western interior. Those paleomagnetic poles define the other, lower-latitude …


Resuscitation Of Microalgae From Mississippi River Plume Sediments, Chase C. Chaplin, Marnie Tabor, Israel A. Marquez, Kanchan Maiti, Jeffrey W. Krause Jan 2019

Resuscitation Of Microalgae From Mississippi River Plume Sediments, Chase C. Chaplin, Marnie Tabor, Israel A. Marquez, Kanchan Maiti, Jeffrey W. Krause

Gulf and Caribbean Research

No abstract provided.


Colloidal And Truly Dissolved Metal(Loid)S In Wastewater Lagoons And Their Removal With Floating Treatment Wetlands, Lauren Sullivan Jan 2019

Colloidal And Truly Dissolved Metal(Loid)S In Wastewater Lagoons And Their Removal With Floating Treatment Wetlands, Lauren Sullivan

Graduate Student Theses, Dissertations, & Professional Papers

Climate change is predicted to cause continuing declines in late-season streamflow, thus increasing the relative contribution of wastewater effluent to surface water flows. Wastewater effluent represents a critical point source of metal and metalloid contamination to aquatic ecosystems and wastewater lagoons are the most common wastewater treatment system in the rural United States. Although the fraction of total wastewater metals and metalloids in "dissolved" forms (defined here asnm) likely drives the potential for negative effects on receiving waters, this broad operational definition lumps truly dissolved solutes (nm) with small colloids and nanomaterials (1-450 nm; hereafter colloids). This size distinction may …


Spatial Estimation Of Hydraulic Properties In Structured Soils At The Field Scale, Xi Zhang Jan 2019

Spatial Estimation Of Hydraulic Properties In Structured Soils At The Field Scale, Xi Zhang

Theses and Dissertations--Plant and Soil Sciences

Improving agricultural water management is important for conserving water during dry seasons, using limited water resources in the most efficient way, and minimizing environmental risks (e.g., leaching, surface runoff). The understanding of water movement in different zones of agricultural production fields is crucial to developing an effective irrigation strategy. This work centered on optimizing field water management by characterizing the spatial patterns of soil hydraulic properties. Soil hydraulic conductivity was measured across different zones in a farmer’s field, and its spatial variability was investigated by using geostatistical techniques. Since direct measurement of hydraulic conductivity is time-consuming and arduous, pedo-transfer functions …


Long-Term Land Management Practices And Their Effect On Soil Health And Crop Productivity, Thomas Joseph Muratore Jr. Jan 2019

Long-Term Land Management Practices And Their Effect On Soil Health And Crop Productivity, Thomas Joseph Muratore Jr.

Theses and Dissertations--Plant and Soil Sciences

Agricultural intensification reliant on monocrops could change soil health in a way that does not support maximum crop productivity. Twenty-nine-year-old no-till field plots at the University of Kentucky Spindletop research farm showed a significant reduction in corn yields from continuous corn plots compared to those from plots in various types of rotation. The objective of this study was to determine what role soil microbes might play in yield reduction and how management and time effects microbial community structure. Samples were collected from the following treatments: continuous corn (CC), continuous soybean (SS), a 2-year corn/soybean rotation (CCSS), Corn in rotation with …


Trawling Through The Five Gyres: A Microplastic Research Study. Subjects: Life Science, Earth Science, Marine/Ocean Science - Grade 6, Meredith Seeley Jan 2019

Trawling Through The Five Gyres: A Microplastic Research Study. Subjects: Life Science, Earth Science, Marine/Ocean Science - Grade 6, Meredith Seeley

Reports

This activity challenges students to help researchers understand what types of plastics are polluting the oceans!

Teachers will prepare samples of microplastics that were collected in each of the 5 ocean gyres, mimicking plastic concentrations actually found in the oceans! Working as a group, students will count the items of plastic and graph their results. They will share their results with the class to compare their gyre to the other four gyres. Finally, students will understand the link between ocean microplastic pollution, and our use of single-use plastics.

This activity can be completed in 45 minutes in the class. An …


Expedition Sediments: Mud's Journey Through The Watershed. Subjects: Earth Science / Environmental Science Grades: 9-12, Jessie Turner Jan 2019

Expedition Sediments: Mud's Journey Through The Watershed. Subjects: Earth Science / Environmental Science Grades: 9-12, Jessie Turner

Reports

Expedition Sediments is a game-in-a-lesson that allows students to explore the movement of sediments through watersheds by moving around the classroom. This lesson explores how grains of estuarine mud and sand move throughout estuaries and coastal regions, with a focus on processes surrounding a highly populated estuary such as the Chesapeake Bay. By the end of the lesson, students will be able to explain how sediments are transported through an estuary, graph sediment residence times in different locations, and compare the timescales of different sediment transport processes.