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Full-Text Articles in Entire DC Network
Fine Scale Mapping Of Laurentian Mixed Forest Natural Habitat Communities Using Multispectral Naip And Uav Datasets Combined With Machine Learning Methods, Parth P. Bhatt
Dissertations, Master's Theses and Master's Reports
Natural habitat communities are an important element of any forest ecosystem. Mapping and monitoring Laurentian Mixed Forest natural communities using high spatial resolution imagery is vital for management and conservation purposes. This study developed integrated spatial, spectral and Machine Learning (ML) approaches for mapping complex vegetation communities. The study utilized ultra-high and high spatial resolution National Agriculture Imagery Program (NAIP) and Unmanned Aerial Vehicle (UAV) datasets, and Digital Elevation Model (DEM). Complex natural vegetation community habitats in the Laurentian Mixed Forest of the Upper Midwest. A detailed workflow is presented to effectively process UAV imageries in a dense forest environment …
Controls On Carbon Gas Fluxes From A Temperate Forest Soil, Natalie A. White, Ruth K. Varner, Clarice R. Perryman
Controls On Carbon Gas Fluxes From A Temperate Forest Soil, Natalie A. White, Ruth K. Varner, Clarice R. Perryman
Honors Theses and Capstones
Forest soils consume atmospheric methane (CH4), serving as a major global CH4 sink that uptake an estimated 22 ± 12 Tg of CH4 per year. Temperature and soil moisture have been identified as key controls of the microbial consumption of CH4 in forest soils. Climate-driven warming and changing moisture regimes may impact forest soils’ role in the carbon cycle, and recent works suggests that forests could become weaker CH₄ sinks. Long-term monitoring sites can capture these changes, leading to better predictions of CH4 exchange between the atmosphere and soils under climate change. This study …
Contributions Of Agroforestry Systems To Food Provisioning Of Peasant Households: Conflicts And Synergies In Chiapas, Mexico, Lorena Soto-Pinto, Sandra Escobar Colmenares, Marina Benítez Kanter, Angelita López Cruz, Erin Estrada Lugo, Balente Herrera Hernández, Estelí Jiménez-Soto
Contributions Of Agroforestry Systems To Food Provisioning Of Peasant Households: Conflicts And Synergies In Chiapas, Mexico, Lorena Soto-Pinto, Sandra Escobar Colmenares, Marina Benítez Kanter, Angelita López Cruz, Erin Estrada Lugo, Balente Herrera Hernández, Estelí Jiménez-Soto
School of Geosciences Faculty and Staff Publications
Traditional agroforestry systems are widely recognized for their contributions to provisioning, support, regulation, and cultural services. However, because of the advancement of industrial agriculture and a corporative food system, peasants' food systems are rapidly undergoing transformation. We identify the contributions of four types of agroforestry systems (AFS)—shade cocoa agroforest, shade coffee agroforest, milpas and homegardens—to food provisioning in peasant families and discuss conflicts between traditional food systems and the contemporary industrial model of production and consumption confronted by peasants and semi-proletarian migrants. We carried out research in 17 peasant communities in Chiapas, Mexico, and conducted 97 semi-structured interviews and agroecological …
Phosphorus Use And Management Based On Fertilizer Placement, Rate Of Application, And Soil Biota In No-Till Situations, Brennan Alexander Bingham Lewis
Phosphorus Use And Management Based On Fertilizer Placement, Rate Of Application, And Soil Biota In No-Till Situations, Brennan Alexander Bingham Lewis
Electronic Theses and Dissertations
Phosphorus (P) pollution has become a concern among multiple scientific organizations as it leads to eutrophication, an algal bloom that depletes lacustrine and marine ecosystems of native species. Multiple strategies can be implemented to reduce phosphorus loss from agriculture fields, which is often implicated as a cause of eutrophication. Soil phosphorus chemistry results in phosphate fertilizers absorbing to clay minerals over time. Soil phosphorus is lost from agricultural fields primarily through wind and water erosion. No-till practices prevent soil erosion, which reduces the phosphorus from loading into waterways. Fertilizer placement affects phosphorus loss. Surface application of phosphorus fertilizers increases the …
Integrating Deep Learning And Hydrodynamic Modeling To Improve The Great Lakes Forecast, Pengfei Xue, Aditya Wagh, Gangfeng Ma, Yilin Wang, Yongchao Yang, Tao Liu, Chenfu Huang
Integrating Deep Learning And Hydrodynamic Modeling To Improve The Great Lakes Forecast, Pengfei Xue, Aditya Wagh, Gangfeng Ma, Yilin Wang, Yongchao Yang, Tao Liu, Chenfu Huang
Civil & Environmental Engineering Faculty Publications
The Laurentian Great Lakes, one of the world’s largest surface freshwater systems, pose a modeling challenge in seasonal forecast and climate projection. While physics-based hydrodynamic modeling is a fundamental approach, improving the forecast accuracy remains critical. In recent years, machine learning (ML) has quickly emerged in geoscience applications, but its application to the Great Lakes hydrodynamic prediction is still in its early stages. This work is the first one to explore a deep learning approach to predicting spatiotemporal distributions of the lake surface temperature (LST) in the Great Lakes. Our study shows that the Long Short-Term Memory (LSTM) neural network, …
Stream Recovery Post Channelization: A Case Study Of Low-Gradient Streams In Central Illinois, Usa, Joseph P. Becker, Eric W. Peterson
Stream Recovery Post Channelization: A Case Study Of Low-Gradient Streams In Central Illinois, Usa, Joseph P. Becker, Eric W. Peterson
Faculty Publications - Geography, Geology, and the Environment
Stream channelization, which entails reducing the sinuosity of a stream, widening, and in some cases deepening the stream channel, is a widespread practice in agricultural regions. Channelization efforts in central Illinois have significant impacts on the geomorphology, flow regime, and sediment transport both in and adjacent to modified reaches. The goal of this study was to characterize the changes in stream channels by comparing three streams that are at various stages of recovery post channelization, 5 years (1900N), 7 years (Frog), and 35 years (Bray), to an unmodified stream reach (Crooked) and estimate a recovery rate. Measured channel slopes within …
Devonian Upper Ocean Redox Trends Across Laurussia: Testing Potential Influences Of Marine Carbonate Lithology On Bulk Rock I/Ca Signals, Ruliang He, Maya Elrick, James Day, Wanyi Lu, Zunli Lu
Devonian Upper Ocean Redox Trends Across Laurussia: Testing Potential Influences Of Marine Carbonate Lithology On Bulk Rock I/Ca Signals, Ruliang He, Maya Elrick, James Day, Wanyi Lu, Zunli Lu
Faculty Publications - Geography, Geology, and the Environment
The Devonian is characterized by major changes in ocean-atmosphere O2 concentrations, colonialization of continents by plants and animals, and widespread marine anoxic events associated with rapid d13C excursions and biotic crises. However, the long-term upper ocean redox trend for the Devonian is still not well understood. This study presents new I/Ca data from well-dated Lower Devonian through Upper Devonian limestone sections from the Great Basin (western Laurussia) and the Illinois Basin (central Laurussia). In addition, to better address potential influences of lithology and stratigraphy on I/Ca redox signals, I/Ca data are reported here as carbonate lithology-specific. Results indicate that lithologic …
Synthesis Of Rna Nucleotides Under Probable Prebiotic Conditions, Ryan Stimson
Synthesis Of Rna Nucleotides Under Probable Prebiotic Conditions, Ryan Stimson
Williams Honors College, Honors Research Projects
RNA being composed of multiple covalently linked nucleotides is thought to have been a precursor to life circa 4.3-3.8 billion years ago. Non-enzymatically formed adenosine monophosphate (AMP), more specifically, is a vitally important subtopic of the self-assembly of the first RNA sequence. The goal of this study was to synthesize AMP non-enzymatically under benign conditions that are likely to have existed on early Earth. In this experiment, 3’,5’-cAMP was successfully formed using wet-dry cycles at 80°C paired with the minerals zeolite beta, hydroxyapatite, and aerosil 300 in the presence of adenosine, urea, and pyrophosphate. A nuclear magnetic resonance spectrometer was …
The Influence Of Hydrogen Peroxide On The Enrichment Of Fe(Iii) Reducing Bacteria From Acid Mine Drainage, Susami Seth
The Influence Of Hydrogen Peroxide On The Enrichment Of Fe(Iii) Reducing Bacteria From Acid Mine Drainage, Susami Seth
Williams Honors College, Honors Research Projects
It is hypothesized that the ocean of Europa, a Jupiter moon, hosts bacteria on its oceanic floor. Understanding how Fe(III) reducing bacteria (FeRB) from AMD utilize organic materials within its surrounding environment outlines how FeRB could thrive and tolerate extreme conditions. FeRB are known to tolerate metals and highly reactive oxidants species (ROS), but in this experiment, H2O2 was the experimental factor to further test FeRB tolerance. H2O2 is a common ROS and is damaging to living material such as proteins, DNA, and RNA. A range of H2O2 concentrations were fed …
An Agronomic-Economic Approach To Connect Manure Nutrients Back To Grain-Producing Regions, Joshua M. Duke, Joshua M. Mcgrath
An Agronomic-Economic Approach To Connect Manure Nutrients Back To Grain-Producing Regions, Joshua M. Duke, Joshua M. Mcgrath
Plant and Soil Sciences Faculty Publications
Stakeholders for nutrient-impaired watersheds have long discussed the causes and consequences of nutrient surpluses associated with intensive livestock production. Nonetheless, nutrient surpluses relative to crop requirement, particularly with phosphorus (P), persist and continue to contribute to water quality impairment. Nutrient life-cycle analysis shows that mineral P, from soil minerals or mined fertilizer P, flows to livestock regions from grain-producing regions. Although creating a return flow of these nutrients to grain fields seems like an easy solution, significant economic obstacles exist to creating a connected manureshed over large geographic distances. To limit the impact of manure use on local surface water, …
Model Of A Biotic Hard Substrate Community: Paleoecology Of Large Trepostome Bryozoans From The Upper Ordovician (Katian) Of The Cincinnati Region, Usa, Kate Runciman
Senior Independent Study Theses
The calcite skeletons of trepostome bryozoan colonies from the Upper Ordovician (Katian) of the Cincinnati region record the diverse interactions and growth responses these colonies experienced. Trepostome specimens from three Cincinnatian strata; the Bellevue Member, the Bull Fork Formation, and the Whitewater Formation, were studied within this project. These three strata were deposited in a shallow epicontinental sea environment that was located in the southern subtropics, approximately 20-23°S at the time of deposition. The focus of this project was the paleoecology of large trepostome bryozoans, which was studied by examining bryozoan growth patterns, trace fossils, and sedimentation. Microscopic examination of …
Male Mastodon Landscape Use Changed With Maturation (Late Pleistocene, North America), Joshua H. Miller, Daniel C. Fisher, Brooke E. Crowley, Ross Secord, Bledar A. Konomi
Male Mastodon Landscape Use Changed With Maturation (Late Pleistocene, North America), Joshua H. Miller, Daniel C. Fisher, Brooke E. Crowley, Ross Secord, Bledar A. Konomi
Department of Earth and Atmospheric Sciences: Faculty Publications
Under harsh Pleistocene climates, migration and other forms of seasonally patterned landscape use were likely critical for reproductive success of mastodons (Mammut americanum) and other megafauna. However, little is known about how their geographic ranges and mobility fluctuated seasonally or changed with sexual maturity. We used a spatially explicit movement model that coupled strontium and oxygen isotopes from two serially sampled intervals (5+ adolescent years and 3+ adult years) in a male mastodon tusk to test for changes in landscape use associated with maturation and reproductive phenology. The mastodon’s early adolescent home range was geographically restricted, with no evidence of …
The Impact Of Sampling Methodology On Soil Bulk Density Measurement By The Clod Method, Aldi J. Airori, Trinity Baker, Judith Turk
The Impact Of Sampling Methodology On Soil Bulk Density Measurement By The Clod Method, Aldi J. Airori, Trinity Baker, Judith Turk
Conservation and Survey Division: Faculty and Staff Publications
The clod method is a widely used and accurate bulk density method. However, its use is limited to sampling from soil pits. This study was conducted to: 1) determine whether clods collected from cores provide similar bulk density measurements to those collected from soil pits and 2) evaluate the impact of various clod bulk density methods on carbon stock calculation. Clods were collected from soil pits, 5.1 cm soil cores, and 8.9 cm soil cores. Three-dimensional laser scanning was used to measure the volume of the soil clods before and after oven-drying and bulk density was calculated as the dry …
Mis 5e Sea-Level History Along The Pacific Coast Of North America, Daniel R. Muhs
Mis 5e Sea-Level History Along The Pacific Coast Of North America, Daniel R. Muhs
United States Geological Survey: Staff Publications
The primary last interglacial, marine isotope substage (MIS) 5e records on the Pacific coast of North America, from Washington (USA) to Baja California Sur (Mexico), are found in the deposits of erosional marine terraces. Warmer coasts along the southern Golfo de California host both erosional marine terraces and constructional coral reef terraces. Because the northern part of the region is tectonically active, MIS 5e terrace elevations vary considerably, from a few meters above sea level to as much as 70m above sea level. The primary paleo-sea-level indicator is the shoreline angle, the junction of the wave-cut platform with the former …
Alpine Shrub Tundra Water Storage And Runoff Dynamics In The Mackenzie Mountains, Sahtú Territory, Nt, Geoffrey Kershaw
Alpine Shrub Tundra Water Storage And Runoff Dynamics In The Mackenzie Mountains, Sahtú Territory, Nt, Geoffrey Kershaw
Theses and Dissertations (Comprehensive)
Alpine regions receive large volumes of precipitation and are important to local and regional water balances, particularly during baseflow periods of winter cold and summer drought when the larger basin area is frozen and/or water limited. Alpine headwaters in western Canada are expected to warm and receive more precipitation during the coming decades, with implications for groundwater recharge and streamflow generation within these systems and the regional river networks to which they contribute. Throughout the North, thawing peat plateaus and other ice-rich permafrost features are resulting in an increased extent of thermokarst and wetland land cover. This transition places infrastructure …
Coastal Landform Change Influences On Endangered Five-Lined Skink Distribution At Northwest Beach, Point Pelee National Park, Canada, Evan Fortushniok
Coastal Landform Change Influences On Endangered Five-Lined Skink Distribution At Northwest Beach, Point Pelee National Park, Canada, Evan Fortushniok
Theses and Dissertations (Comprehensive)
As park visitation increased to Point Pelee National Park up until its peak in 1963, the installation of infrastructure for the purpose of supporting the recreational interest grew with it. At Northwest Beach, large parking lots were built into the coastal landscape and by the 1970s large areas of sand dunes continued to be heavily impacted by the installation of visitor associated infrastructure. The infrastructure resulted in the stabilization of sand on the beach side of the parking lot, resulting in an artificially stabilized and heavily vegetated dune. Over the last few decades, the park slowly reduced the size and …
Influence Of Abiotic Drivers On 1-Year Seedling Survival Of Six Mangrove Species In Southeast Asia, Taylor M. Sloey, Kiah Eng Lim, Jared Moore, Jie Min Heng, Jia Min Heng, Michiel Van Breugel
Influence Of Abiotic Drivers On 1-Year Seedling Survival Of Six Mangrove Species In Southeast Asia, Taylor M. Sloey, Kiah Eng Lim, Jared Moore, Jie Min Heng, Jia Min Heng, Michiel Van Breugel
Biological Sciences Faculty Publications
Establishment and survival of plant species in systems with dominant environmental drivers (i.e. factors that exert disproportionate control over species establishment and survival) is often thought to be dominated by one master variable. In forested wetlands such as mangroves, hydrology is typically considered the dominant limiting driver. At the same time, light is a major driver of plant community dynamics, with some of the best understood plant life-history tradeoffs related to fast growth under high-light conditions versus survival under low-light conditions. Yet light is given relatively limited consideration in mangrove research compared to other drivers. Understanding the relative importance of …
Trapped Under Ice: Spatial And Seasonal Dynamics Of Dissolved Organic Matter Composition In Tundra Lakes, Martin R. Kurek, Karen E. Frey, François Guillemette, David C. Podgorski, Amy Townsend-Small, Christopher D. Arp, Anne M. Kellerman, Robert G.M. Spencer
Trapped Under Ice: Spatial And Seasonal Dynamics Of Dissolved Organic Matter Composition In Tundra Lakes, Martin R. Kurek, Karen E. Frey, François Guillemette, David C. Podgorski, Amy Townsend-Small, Christopher D. Arp, Anne M. Kellerman, Robert G.M. Spencer
Geography
Arctic lakes store, modify, and transport large quantities of carbon from terrestrial environments to the atmosphere; however, the spatial and temporal relationships between quantity and composition of dissolved organic matter (DOM) have not been well characterized across broad arctic regions. Moreover, most arctic lake DOM compositions have been examined during the ice-free summer, whereas DOM cycling between the ice-covered winter months and summer have not been addressed. To resolve these spatial and seasonal uncertainties in DOM cycling, we sampled a series of arctic lakes from the North Slope of Alaska across a latitudinal gradient in the winter and summer over …
Transport Of Polyethylene Microplastic Spheres In A Sandy Aquifer, Alyssa Marie Graveline
Transport Of Polyethylene Microplastic Spheres In A Sandy Aquifer, Alyssa Marie Graveline
Graduate Research Theses & Dissertations
Microplastic particles are currently listed as a Contaminant of Emerging Concern (CEC) since they are in much of Earth’s water systems and recent studies indicate plastic particles can sorb toxic contaminants. Microplastics (MP) are defined as plastic particles under 5 mm in length. Currently, there is a paucity of data on the transport of MP in the subsurface. This study investigated the transport, filtration, retardation, and influence of 5-100ߎm plastic polyethylene spheres in a shallow sandy aquifer over a distance of 1m by utilizing two forced hydraulic gradient tracer studies. Slug tests were used to estimate hydraulic conductivity prior and …
Impact Of Prairie Restoration On Geochemistry And Microbial Communities In Groundwater, Kayla Koenig
Impact Of Prairie Restoration On Geochemistry And Microbial Communities In Groundwater, Kayla Koenig
Graduate Research Theses & Dissertations
Prairie restoration is important for reversing the loss of biodiversity and repairing ecosystem functions humanity is dependent on diverse ecosystems. This study looks at the impact of the beginning phases of prairie restoration on groundwater geochemistry and microbial communities the relationship between them. This research project studied the geochemistry and microbial communities in five wells before, during, and after the beginning phases of the first year of a prairie restoration on the Northern Illinois University campus. Water samples were collected bimonthly for a year and analyzed on an Ion Chromatograph. Microbial samples were collected monthly and underwent DNA extraction, amplification, …
Comparison Of Topsoil Moisture In E3sm Model Simulations And In-Situ Observations Over Illinois, Jacinda Lee Mayer
Comparison Of Topsoil Moisture In E3sm Model Simulations And In-Situ Observations Over Illinois, Jacinda Lee Mayer
Graduate Research Theses & Dissertations
Soil moisture stimulates land-atmosphere interactions by modifying energy and water fluxes in the boundary layer and it plays an important role in climate change studies. The objective of this research is to quantify the spatial and temporal variations of the Illinois Climate Network’s (ICN) observed topsoil moisture, as well as evaluate how accurately the new climate model, E3SM, is simulating soil moisture compared to the observed data during 2003-2014. Observed topsoil moisture averaged over growing season during the 12-year period indicates a general dry-north and wet-south pattern in Illinois, and northeast and southwest become drier with the progression of the …
Exploring The Morphometrics Of The Diatom Fragilariopsis Kerguelensis As A Proxy For Paleo-Sea Surface Temperature In The Late Pleistocene-Holocene Southern Ocean, Joseph Anthony Ruggiero
Exploring The Morphometrics Of The Diatom Fragilariopsis Kerguelensis As A Proxy For Paleo-Sea Surface Temperature In The Late Pleistocene-Holocene Southern Ocean, Joseph Anthony Ruggiero
Graduate Research Theses & Dissertations
The Southern Ocean has played a large role in moderating global climate since its inception in the Oligocene. With the onset of anthropogenic global warming, it is now more necessary than ever that we understand the world’s climate during periods of rapidly fluctuating temperature in the past. Climatic forecasts are informed by paleoenvironmental conditions of the past during these turbulent periods, which we can examine using proxy data. This thesis assesses a potential proxy for Sea Surface Temperature (SST) through morphometric analysis of the Southern Ocean diatom Fragilariopsis kerguelensis in the Amundsen Sea, West Antarctica. This proxy is based off …
Combined Effects Of Temperature And Heavy Metals On The Performance Of The Giant Salmonfly., James Frakes, Amanda Andreas, Benjamin P. Colman, Aurthur Woods
Combined Effects Of Temperature And Heavy Metals On The Performance Of The Giant Salmonfly., James Frakes, Amanda Andreas, Benjamin P. Colman, Aurthur Woods
Graduate Student Theses, Dissertations, & Professional Papers
In many freshwater ecosystems, communities of aquatic insects are facing the combined stresses of warmer waters due to climate change and increased exposure to heavy metal toxicants. Although each stressor may threaten aquatic insects independently, they also likely interact in important ways to affect insect physiology and performance. Here we investigate this potential interaction using two populations of aquatic nymphs of the giant salmonfly, Pteronarcys californica, collected from adjacent rivers in Montana: naïve individuals from Rock Creek, a relatively pristine stream, and individuals from the Upper Clark Fork River, which has a history of heavy metal pollution and higher …
A Non-Deterministic Deep Learning Based Surrogate For Ice Sheet Modeling, Hannah Jordan
A Non-Deterministic Deep Learning Based Surrogate For Ice Sheet Modeling, Hannah Jordan
Graduate Student Theses, Dissertations, & Professional Papers
Surrogate modeling is a new and expanding field in the world of deep learning, providing a computationally inexpensive way to approximate results from computationally demanding high-fidelity simulations. Ice sheet modeling is one of these computationally expensive models, the model used in this study currently requires between 10 and 20 minutes to complete one simulation. While this process is adequate for certain applications, the ability to use sampling approaches to perform statistical inference becomes infeasible. This issue can be overcome by using a surrogate model to approximate the ice sheet model, bringing the time to produce output down to a tenth …
Creating An Arcgis Dashboard For Climate Data Management And Visualization, Sydney Noel Case
Creating An Arcgis Dashboard For Climate Data Management And Visualization, Sydney Noel Case
Senior Independent Study Theses
The College of Wooster Department of Earth Sciences has collected over the past 12 years (and continues to collect) hourly local climate indicator data including stream level and temperature, air temperature and pressure, precipitation levels, and relative humidity. This data is collected at the College’s research station, Fern Valley, located in Holmes County, Ohio and serves as a storytelling component for regional climate change. Upon initial investigation, the extensive dataset revealed a fundamental data storage problem within Earth Sciences, as there lacked a singular location to store complex datasets. Several technological solutions were explored to create a long-term data storage, …
Unearthing The Effects Of European-American Settlement On A Northeast Ohio Kettle Lake Through Diatom Stratigraphy, Justine Paul A. Berina
Unearthing The Effects Of European-American Settlement On A Northeast Ohio Kettle Lake Through Diatom Stratigraphy, Justine Paul A. Berina
Senior Independent Study Theses
Recently, wetland conservation has highlighted the necessity for assessing limnological changes following European-American settlement. A prior study at Brown's Lake (northeast Ohio) identified a stratigraphic sequence that shows an abrupt transition from organic-rich muds to several centimeters of a bright loess layer, then a recovery to organic-rich sediments near the top. Based on 210Pb dates, the loess deposition occurred before 1846 CE, when a growing population cleared trees and farmed intensively. Likewise, organics had recovered after 1950 CE, when people abandoned farmland and practiced conservation tillage. However, the effects of settlement on limnology are poorly known. Diatoms (microscopic algae; …
Interaction With Augmented Reality Sandbox Does Not Produce Greater Gains In Topographic Map Skills For Undergraduate Students, Celeste Kenworthy
Interaction With Augmented Reality Sandbox Does Not Produce Greater Gains In Topographic Map Skills For Undergraduate Students, Celeste Kenworthy
Honors Program: Senior Projects (Public)
The augmented reality (AR) sandbox allows students to interact with topographic maps in a 3D space. Being able to understand topographic maps is important to geologists and they are taught in many introductory geology courses. Recent research has focused on whether the AR sandbox can improve students’ topographic map skills. Previous studies have found that students who interact with the AR sandbox do not score significantly better on topographic map assessments (TMAs) than their peers. One proposed reason for this is the limited time students have to interact with the AR sandbox. This study sought to address this by creating …
การจำลองการรั่วไหลของน้ำมันบริเวณอ่าวไทยตอนบน, กิตติยา แย้มภิรมย์ศรี
การจำลองการรั่วไหลของน้ำมันบริเวณอ่าวไทยตอนบน, กิตติยา แย้มภิรมย์ศรี
Chulalongkorn University Theses and Dissertations (Chula ETD)
สถิติการเกิดน้ำมันรั่วไหลในประเทศไทยตั้งแต่อดีตถึงปัจจุบันของกรมเจ้าท่า พบว่าเกิดน้ำมันที่รั่วไหลในทะเลอ่าวไทยตอนบนหลายครั้ง โดยมีสาเหตุมาจากเรือขนส่งสินค้า เรือขนถ่ายน้ำมัน เกิดอุบัติเหตุกลางทะเล อันเป็นผลมาจากความชำรุดของอุปกรณ์เดินเรือ หรือสภาพภูมิอากาศที่ไม่ดีต่อการเดินเรือ ยังส่งผลกระทบต่อชีวิต ทรัพย์สิน และสิ่งแวดล้อมอย่างมาก เพราะบริเวณอ่าวไทยตอนบนมีพื้นที่ชุมชนชายฝั่งทะเล และแหล่งเพาะพันธุ์สัตว์น้ำ การศึกษาในครั้งนี้มีวัตถุประสงค์เพื่อศึกษาการจำลองการรั่วไหลของน้ำมันบริเวณอ่าวไทยตอนบน โดยใช้แบบจำลองทางคณิตศาสตร์ในการคาดการณ์การเคลื่อนที่ของคราบน้ำมันที่รั่วไหลในทะเล ประกอบด้วยแบบจำลอง 3 ชนิด คือแบบจำลอง SWAN ใช้ในการจำลองคลื่นที่เกิดจากลม, แบบจำลอง Delft3D ใช้ในการจำลองกระแสน้ำเนื่องจากอิทธิพลของน้ำขึ้นน้ำลงและคลื่นลม และแบบจำลอง GNOME ใช้ในการจำลองการรั่วไหลของน้ำมันในทะเลบริเวณอ่าวไทยตอนบน ผลของแบบจำลองแบ่งออกเป็น 2 ส่วน คือ การจำลองคลื่นและกระแสน้ำ และการจำลองการเคลื่อนที่ของคราบน้ำมันที่รั่วไหลในทะเลอ่าวไทยตอนบน ความสูงคลื่นนัยสำคัญเป็นผลที่ได้การจำลองคลื่นด้วยแบบจำลอง SWAN มีการปรับเทียบและสอบทานข้อมูลจากแบบจำลองกับข้อมูลตรวจวัดจากทุ่นสมุทรศาสตร์ของสำนักงานพัฒนาเทคโนโลยีอวกาศและภูมิศาสตร์สารสนเทศ ในปี พ.ศ.2540 – 2545 ที่สถานีสถานีหัวหิน, สถานีเพชรบุรี และสถานีเกาะสีชัง กระแสน้ำเนื่องจากน้ำขึ้นน้ำลงและกระแสน้ำสุทธิที่เป็นผลรวมของน้ำขึ้นน้ำลงและคลื่นลมจากแบบจำลอง Delft3D ถูกปรับเทียบและสอบทานโดยใช้ระดับน้ำจากแบบจำลองกับข้อมูลระดับน้ำทำนายของกรมอุทกศาสตร์ กองทัพเรือ ในปี พ.ศ. 2549 – 2559 ที่สถานีหัวหิน, สถานีสันดอนเจ้าพระยา, สถานีเกาะสีชัง และสถานีอ่าวสัตหีบ จากการศึกษาคลื่นและกระแสน้ำพบว่ากระแสน้ำที่เป็นอิทธิพลหลักบริเวณอ่าวไทยตอนบนคือกระแสน้ำเนื่องจากอิทธิพลของน้ำขึ้นน้ำลง จึงใช้กระแสน้ำเนื่องจากน้ำขึ้นน้ำลงในการศึกษาการเคลื่อนที่ของคราบน้ำมันที่รั่วไหลในทะเลต่อไป การศึกษาการเคลื่อนที่ของคราบน้ำมันที่รั่วไหลในทะเลอ่าวไทย ทำการปรับเทียบและสอบทานแบบจำลอง GNOME ด้วยข้อมูลภาพถ่ายดาวเทียมของสำนักงานพัฒนาเทคโนโลยีอวกาศและภูมิสารสนเทศ (GISTDA) ในช่วงเกิดเหตุการณ์น้ำมันรั่วบริเวณปากแม่น้ำเจ้าพระยา วันที่ 3 ธันวาคม พ.ศ.2562 พบว่าการเคลื่อนที่ของคราบน้ำมันมีทิศทางสอดคล้องกับทิศทางของลม ในการศึกษานี้ประยุกต์ใช้แบบจำลองโดยการวิเคราะห์การเคลื่อนที่ของคราบน้ำมันในช่วงน้ำเกิดและน้ำตายรายเดือน ทำให้สามารถประมาณช่วงเวลาและตำแหน่งที่น้ำมันเคลื่อนที่กระทบชายฝั่งทะเล และสรุปได้ว่าการเคลื่อนที่ของคราบน้ำมันที่รั่วไหลมีการเปลี่ยนแปลงตามปัจจัยของชนิดน้ำมัน, คุณสมบัติการแพร่กระจายของน้ำมัน, ข้อมูลลม และข้อมูลกระแสน้ำในทะเล
Performance Of Black Soldier Fly Frass Fertiliser On Maize (Zea Mays L.) Growth, Yield, Nutritional Quality, And Economic Returns, C. M. Tanga, D. Beesigamukama, M. Kassie, P. J. Egonyu, Changeh J. Ghemoh, Kiatoko Nkoba, S. Subramanian, A. O. Anyega, S. Ekesi
Performance Of Black Soldier Fly Frass Fertiliser On Maize (Zea Mays L.) Growth, Yield, Nutritional Quality, And Economic Returns, C. M. Tanga, D. Beesigamukama, M. Kassie, P. J. Egonyu, Changeh J. Ghemoh, Kiatoko Nkoba, S. Subramanian, A. O. Anyega, S. Ekesi
All Peer-Reviewed Publications
Although the black soldier fly frass fertiliser (BSFFF) is globally recognised as a promising and potential high-quality organic fertiliser, there is inadequate information on its impact on the growth performance and nutritional status of maize. Furthermore, no information exist on their combination with mineral fertiliser (NPK) as well as economic impact on maize production. This study evaluated the comparative impact of BSFFF, NPK and commercial organic fertiliser (Evergrow®) on growth, nitrogen use efficiency, yield, nutritional quality, and profitability of maize under greenhouse conditions. The treatments included: (1) sole application of BSFFF, conventional compost of brewers’ spent grain (BSG), Evergrow, and …
Biotic Characteristics Of Managed And Unmanaged Coastal Dunes In The Outer Banks, North Carolina, Andrew E. White
Biotic Characteristics Of Managed And Unmanaged Coastal Dunes In The Outer Banks, North Carolina, Andrew E. White
Theses and Dissertations
Under future climate change and sea level rise scenarios, Natural and Nature-Based Features (e.g., dunes) that protect coastal habitat and infrastructure will be exposed to increased wave energy and storm surge. Understanding how these forces will impact coastal dunes is necessary for their continued use as protective features. Coastal dunes develop through feedback between vegetation and sediment deposition, a process complicated by species-specific growth rates and responses to burial. Wave flume studies have tested the effects of dune vegetation on erosion and found multiple plant organs across several functional types to be important for resisting erosion. Although dune building and …