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Shifting Waters: A 41-Year Time-Series Analysis Of Surface Water Change In The Prairie Pothole Region, Madison Dejarlais Jan 2025

Shifting Waters: A 41-Year Time-Series Analysis Of Surface Water Change In The Prairie Pothole Region, Madison Dejarlais

Electronic Theses and Dissertations

The Prairie Pothole Region (PRR) is a landscape defined by a dynamic surface water system, with wetlands, lakes, and rivers playing critical roles in supporting biodiversity, regulating floods, and maintaining hydrological balance. This study conducts a time-series analysis of surface water change in the PPR from 1984 to 2024, using remote sensing tools including Google Earth Engine, ArcGIS Pro, and ENVI. 41 annual surface water presence rasters were compiled into a cumulative dataset, allowing for both year-to-year comparisons and broader trend analysis. Results indicate that the presence of surface water in the PPR has not followed a simple linear trend. …


Investigating Non-Invasive Survey Methods And Building A Predictive Occupancy Model For Harlequin Ducks (Histrionicus Histrionicus) In Western Montana And Northern Idaho, Holli Ann Holmes Jan 2025

Investigating Non-Invasive Survey Methods And Building A Predictive Occupancy Model For Harlequin Ducks (Histrionicus Histrionicus) In Western Montana And Northern Idaho, Holli Ann Holmes

Graduate Student Theses, Dissertations, & Professional Papers

Harlequin Ducks (Histrionicus histrionicus; HADU) are an imperiled sea duck that breeds along white-water mountain streams, but challenges in surveying them have made it difficult to understand population trends in their Northern Rocky Mountain breeding population. In this study we had two objectives: (1) evaluate non-invasive survey methods for detecting HADU on their breeding grounds in Western Montana and Northern Idaho, and (2) develop an occupancy model to predict potential breeding stream use for HADU across the region. First, we assessed the efficacy of ground-based foot surveys (GBS), environmental DNA (eDNA), and camera traps to detect breeding HADU during …


Impacts Of Fire-Driven Vegetation Changes On Evapotranspiration In North American Boreal Forests, Tyler Glen Albrethsen Jan 2025

Impacts Of Fire-Driven Vegetation Changes On Evapotranspiration In North American Boreal Forests, Tyler Glen Albrethsen

Graduate Student Theses, Dissertations, & Professional Papers

A growing body of evidence suggests that land cover change could be impacting evapotranspiration (ET) trends more than the direct impacts of climate change (Dashti et al., 2022; Zhang et al., 2015). In boreal forests, one of the Earth’s most important carbon sinks (Kang et al., 2006), climate and disturbance-driven land cover change is progressing rapidly, threatening the resilience of conifer-dominated forests (Baltzer et al., 2021; Massey et al., 2023). The spread of deciduous trees and the changing structure of boreal forests likely have large implications for the magnitude and seasonality of ecosystem water fluxes (Young-Robertson et al., 2016). This …


Mapping Mesic Resilience In Western Rangelands: Productivity Trends, Predictors, And Targeting Frameworks, Kristopher Robert Mueller Jan 2025

Mapping Mesic Resilience In Western Rangelands: Productivity Trends, Predictors, And Targeting Frameworks, Kristopher Robert Mueller

Graduate Student Theses, Dissertations, & Professional Papers

Mesic ecosystems in riparian areas and wetlands make up only 2% of western U.S. rangelands but support 80% of wildlife during dry periods, providing vital late-season forage and refuge when surrounding uplands dry out. Yet, mesic habitats are often overlooked in landscape-scale conservation planning. This thesis addresses two key gaps: understanding how mesic productivity responds to environmental change and developing frameworks to incorporate these habitats into current conservation strategies. Using 40 years of Landsat imagery (1984–2024), we examined long-term trends in late-season mesic vegetation productivity and its relationship with drought across the sagebrush biome. From 1984 to 2004, mesic productivity …


Binoculars To Bytes: Development And Field Validation Of An Ai-Driven System For Avian Monitoring, Christian J. Dupree Jan 2025

Binoculars To Bytes: Development And Field Validation Of An Ai-Driven System For Avian Monitoring, Christian J. Dupree

Graduate Student Theses, Dissertations, & Professional Papers

Autonomous camera-trap arrays coupled with artificial-intelligence (AI) vision can lift bird monitoring beyond the spatial, temporal, and labor limits of traditional field surveys. We present Binoculars to Bytes (B2B), an open-source pipeline that turns 180–360° time-lapse imagery into analysis-ready avian data. At Freezout Lake Wildlife Management Area (Montana, USA) the system ran four-hour morning deployments during spring and fall migrations (2023–2024). A YOLO-NAS detector, incrementally refined with a “Specialized Localized Iterative Model” workflow, quadrupled local accuracy and, after confidence-based species-binning, cut false-positive rates in half. Daily AI species lists were benchmarked against contemporaneous eBird citizen-science checklists and recovered ≥ …


Assessing Inter-Organizational Collaboration Within The Transboundary Network Governing The Conservation Of Southern Resident Killer Whales, Dane Pedersen, Owen Temby, Antonia Sohns, Evelyn Roozee, Gordon M. Hickey Jan 2025

Assessing Inter-Organizational Collaboration Within The Transboundary Network Governing The Conservation Of Southern Resident Killer Whales, Dane Pedersen, Owen Temby, Antonia Sohns, Evelyn Roozee, Gordon M. Hickey

School of Earth, Environmental, & Marine Sciences Faculty Publications

The Southern Resident Killer Whale (SRKW) is an endangered and charismatic species whose home range spans the Salish Sea, an ecosystem that extends across the Canada-US border. Conserving and recovering the SRKW represents a high-profile transboundary governance challenge that depends heavily on collaboration between a wide range of organizations. To better understand the factors affecting transboundary SRKW governance in the Salish Sea, this study applies a multi-dimensional trust, control, perceived risk framework to assess the inter-organizational architecture supporting collaboration. The analysis is based on key informant interviews (n=32) and surveys (n=35) conducted with policy actors working for different organizations involved …


A New G Family: Properties, Characterizations, Different Estimation Methods And Port-Var Analysis For U.K. Insurance Claims And U.S. House Prices Data Sets, Ahmad M. Aboalkhair, Gholamhossein Hamedani, Nazar Ali Ahmed, Mohamed Ibrahim, Mohammad A. Zayed, Haitham M. Yousof Jan 2025

A New G Family: Properties, Characterizations, Different Estimation Methods And Port-Var Analysis For U.K. Insurance Claims And U.S. House Prices Data Sets, Ahmad M. Aboalkhair, Gholamhossein Hamedani, Nazar Ali Ahmed, Mohamed Ibrahim, Mohammad A. Zayed, Haitham M. Yousof

Mathematical and Statistical Science Faculty Research and Publications

This paper introduces a new class of probability distributions, termed the generated log exponentiated polynomial (GLEP) family, designed to enhance flexibility in modeling complex real financial data. The proposed family is constructed through a novel cumulative distribution function that combines logarithmic and exponentiated polynomial structures, allowing for rich distributional shapes and tail behaviors. We present comprehensive mathematical properties, including useful series expansions for the density, cumulative, and quantile functions, which facilitate the derivation of moments, generating functions, and order statistics. Characterization results based on the reverse hazard function and conditional expectations are established. The model parameters are estimated using various …


A Bayesian Complex-Valued Latent Variable Model Applied To Functional Magnetic Resonance Imaging, Chase J. Sakitis, D. Andrew Brown, Daniel B. Rowe Jan 2025

A Bayesian Complex-Valued Latent Variable Model Applied To Functional Magnetic Resonance Imaging, Chase J. Sakitis, D. Andrew Brown, Daniel B. Rowe

Mathematical and Statistical Science Faculty Research and Publications

In linear regression, the coefficients are simple to estimate using the least squares method with a known design matrix for the observed measurements. However, real-world applications may encounter complications such as an unknown design matrix and complex-valued parameters. The design matrix can be estimated from prior information but can potentially cause an inverse problem when multiplying by the transpose as it is generally ill-conditioned. This can be combat by adding regularizers to the model but does not always mitigate the issues. Here, we propose our Bayesian approach to a complex-valued latent variable linear model with an application to functional magnetic …


Bayesian Merged Utilization Of Grappa And Sense (Bmugs) For In-Plane Accelerated Reconstruction Increases Fmri Detection Power, Chase J. Sakitis, Daniel B. Rowe Jan 2025

Bayesian Merged Utilization Of Grappa And Sense (Bmugs) For In-Plane Accelerated Reconstruction Increases Fmri Detection Power, Chase J. Sakitis, Daniel B. Rowe

Mathematical and Statistical Science Faculty Research and Publications

In fMRI, capturing brain activity during a task is dependent on how quickly the k-space arrays for each volume image are obtained. Acquiring the full k-space arrays can take a considerable amount of time. Under-sampling k-space reduces the acquisition time, but results in aliased, or “folded,” images after applying the inverse Fourier transform (IFT). GeneRalized Autocalibrating Partial Parallel Acquisition (GRAPPA) and SENSitivity Encoding (SENSE) are parallel imaging techniques that yield reconstructed images from subsampled arrays of k-space. With GRAPPA operating in the spatial frequency domain and SENSE in image space, these techniques have been separate but can …


A Survey On Non-Invasive Computing: Neurological-Hematological Framework For Early Infection And Stroke Detection With Future Directions, Masud Rabbani, Nafi Us Sabbir Sabith, Sheikh Iqbal Ahamed Jan 2025

A Survey On Non-Invasive Computing: Neurological-Hematological Framework For Early Infection And Stroke Detection With Future Directions, Masud Rabbani, Nafi Us Sabbir Sabith, Sheikh Iqbal Ahamed

Computer Science Faculty Research and Publications

This paper introduces a novel, non-invasive tool for building a holistic neurological-hematological diagnostic framework that can be used for early detection of infection and stroke. We proposed and developed a multimodal sensing approach, where an ear canal–based acoustic system can be used to identify brain activities and a smartphone-based facial video analysis platform to estimate white blood cell (WBC) and hemoglobin (Hb) levels. Our ear-based EEG methodology achieved a remarkable 96% classification accuracy from the low-frequency level (>30hz), with regression models with mean R2 scores above 0.96 across all EEG bands. For hematological diagnostics, the system predicted WBC counts …


Bibliometric And Visualisation Analysis Of Biomass Burning Research In Thailand (1997-2024), Weerachon Sawangproh, Arika Bridhikitti Jan 2025

Bibliometric And Visualisation Analysis Of Biomass Burning Research In Thailand (1997-2024), Weerachon Sawangproh, Arika Bridhikitti

Applied Environmental Research

Biomass burning is a major driver of air pollution and climate-related impacts in Thailand, but a national-level synthesis of research efforts is lacking. This study conducts a comprehensive bibliometric and qualitative review of 256 peer-reviewed publications from 1997–2024, using Scopus-indexeddata to explore research trends, thematic patterns, and existing gaps. The analysis reveals a strong emphasis on atmospheric chemistry, air quality modeling, and remote sensing, which collectively account for more than 60% of the research landscape.Studies frequently focus on pollutants such as PM2.5,PAHs, carbon monoxide, and heavy metals, with biomass burning identified as a dominant source, especiallyduring the dry season in …


Quantifying Biodiversity In The Absence Of Taxonomic Data: A Study Of Thailand’S Economic Development Zones, Nikorn Mahawan, Wanpen Charoentrakulpeeti Jan 2025

Quantifying Biodiversity In The Absence Of Taxonomic Data: A Study Of Thailand’S Economic Development Zones, Nikorn Mahawan, Wanpen Charoentrakulpeeti

Applied Environmental Research

The biodiversity status measures the ecological capacity of a given area. However, biodiversity assessments in developing countries are limited by the absence of taxonomic data on plants and animals. By developing methods to evaluate biodiversity via alternative data, it is now possible to quantify the ecological carrying capacity in areas where taxonomic data are lacking. The relationship between forest ecosystem health and biodiversity values can be used to estimate biodiversity values by considering the proportions of different land use types that are associated with forest ecosystem abundance. The biodiversity value of the area can be assessed by adding the abundance …


Spatial And Temporal Dynamics Of Water Use Efficiency And Climate Influence In The Central Highlands Of Vietnam Via Satellite Time Series, Thi Nguyen Quang, Hoang Van Hung Jan 2025

Spatial And Temporal Dynamics Of Water Use Efficiency And Climate Influence In The Central Highlands Of Vietnam Via Satellite Time Series, Thi Nguyen Quang, Hoang Van Hung

Applied Environmental Research

This study investigates the spatial and temporal patterns of water use efficiency (WUE) anomalies across the Central Highlands of Vietnam from 2001–2024 via MODIS time series data, with a focus on seasonal differences and climatic drivers. The results revealed pronounced interannual and spatial variability in the WUE, with significant improvements observed during 2004, 2015, and 2021–2024 and substantial declines during 2005–2008, 2010–2013, and 2016–2017, which coincided with major drought events in the region. Seasonal analysis indicated that WUE was lower during the early dry season and peaked during the postmonsoon months (October–November), reflecting the interplay between water availability and vegetation …


Using A Water Quality Index To Assess The Impacts Of Heavy Metals Contamination For Sustainable Water Management: A Case Study Of The Bang Pakong River, Thailand, Khin Yadana Soe, Pokchat Chutivisut, Wilailuk Niyommaneerat Jan 2025

Using A Water Quality Index To Assess The Impacts Of Heavy Metals Contamination For Sustainable Water Management: A Case Study Of The Bang Pakong River, Thailand, Khin Yadana Soe, Pokchat Chutivisut, Wilailuk Niyommaneerat

Applied Environmental Research

Anthropogenic activities such as improper waste disposal, excessive fertilizer use, and industrial effluents cause heavy metal contamination in water, soil, and the atmosphere. Herein, the water quality index (WQI) was used to characterize heavy metal (i.e., cadmium (Cd), arsenic (As), and mercury (Hg)) contamination in the Bang Pakong River, Thailand. Specifically, water samples were collected during the dry season from four stations along the river from 2012–2022. The heavy metal concentrations in the samples were analyzed via atomic absorption spectrophotometry, and WQI values were calculated on the basis of standard water quality parameters. At the four sampling stations, high As …


Halotolerant Biodegradation And Detoxification Of Synthetic Dyes By Marine-Derived Penicillium Oxalicum M6a: Metabolite Profiling And Ecotoxicity Assessment, Ugochukwu Okechukwu Ozojiofor, Mohammed Sani Abdulsalami, Nkechi Eucharia Egbe, Ahmed Ali Haroun, Yakubu Magaji Jan 2025

Halotolerant Biodegradation And Detoxification Of Synthetic Dyes By Marine-Derived Penicillium Oxalicum M6a: Metabolite Profiling And Ecotoxicity Assessment, Ugochukwu Okechukwu Ozojiofor, Mohammed Sani Abdulsalami, Nkechi Eucharia Egbe, Ahmed Ali Haroun, Yakubu Magaji

Applied Environmental Research

The complex aromatic structures of synthetic dyes in contaminated water bodies make them difficult to degrade, posing a serious environmental challenge and representing a significant emerging pollutant that warrants urgent intervention. This study evaluated the biodegradation and detoxification potential of a halotolerant, marine-derived fungal strain, Penicillium oxalicum M6A, isolated from the Nigerian coastline, against Indigo carmine (IC) and Remazol Brilliant Blue R (RBBR). The effects of pH, temperature, salinity, and dye concentration on degradation efficiency, alongside enzymatic activity, were assessed. FTIR and GC‒MS analyses were employed to identify degradation products and predict metabolic pathways, whereas toxicity was evaluated in three …


Blue Carbon Stock Assessment Of The Mangrove Swamp Forest Reserve In Baganga, Davao Oriental, Philippines, Renz Morales Lanaban, Yves Paul M. Montero, Hilario L. Wong, Jr., Marnie Grace I. Sonico Jan 2025

Blue Carbon Stock Assessment Of The Mangrove Swamp Forest Reserve In Baganga, Davao Oriental, Philippines, Renz Morales Lanaban, Yves Paul M. Montero, Hilario L. Wong, Jr., Marnie Grace I. Sonico

Applied Environmental Research

Mangrove ecosystems are vital carbon sinks, yet they are threatened by anthropogenic pressures and natural disturbances, causing significant carbon stock losses. Given the limited data for Baganga, Davao Oriental, this study quantified the aboveground biomass (AGB) and blue carbon stock in the Lucod mangrove swamp forest reserve. We identified mangrove species, measured AGB and carbon content via allometric equations, and compared storage among species. The results indicated that the mangrove forest AGB was within typical ranges for tropical wet regions and the Asia-Pacific region, but its overall carbon content did not reach highly productive ecosystem levels. Nonparametric analysis revealed significant …


Spatial Distribution And Potential Ecological Risk Of Microplastics In Surface Sediments Of The Inner Gulf Of Thailand, Sarayut Suanluang, Pathompong Vibhatabandhu, Sarawut Srithongouthai Jan 2025

Spatial Distribution And Potential Ecological Risk Of Microplastics In Surface Sediments Of The Inner Gulf Of Thailand, Sarayut Suanluang, Pathompong Vibhatabandhu, Sarawut Srithongouthai

Applied Environmental Research

The global surge in plastic usage during the COVID–19 pandemic raised concerns about increased microplastic (MP) contamination in aquatic environments. This study assessed the abundance, characteristics, and ecological risk of MPs in surface sediments of the inner Gulf of Thailand during the post–COVID–19 period (April 2021). The sediment samples were analyzed via density separation, stereomicroscopic examination, and polymer identification via micro–FTIR. The mean MP abundance was 196.07 ± 85.60 pieces kg-1, with concentrations ranging from 73.08 to 351.19 pieces kg-1. PTFE and PP were the dominant polymer types, comprising 50% and 32% of all the MPs, respectively. Fibers (34%) and …


Health Risk Assessment Of Copper Exposure Through Hand-To-Mouth Activities In The Lithium-Ion Battery Manufacturing Industry, Adisorn Phungkum, Worawat Meevasana, Khanidtha Marungrueang Jan 2025

Health Risk Assessment Of Copper Exposure Through Hand-To-Mouth Activities In The Lithium-Ion Battery Manufacturing Industry, Adisorn Phungkum, Worawat Meevasana, Khanidtha Marungrueang

Applied Environmental Research

This study aims to evaluate the occupational exposure levels of copper (Cu) among workers in a battery manufacturing facility by analyzing the Cu concentrations on hand surfaces at three distinct time periods: before work (BW), before lunch (BL), and after work (AW). A total of 30 workers involved in 13 different workstations or tasks—such as battery cell preparation, spot welding, soldering, and labeling—were included in the study to reflect diverse exposure scenarios. Surface wipe sampling was conducted according to NIOSH Method 9102, and the Cu concentrations were quantified via inductively coupled plasma‒mass spectrometry (ICP‒MS). Additionally, the hazard quotient (HQ) was …


Spatial Estimation Of Trophic State For Reservoir Using Ground Monitoring And Remote Sensing Data, Thong Nguyen Hoang, Van Tran Thi Jan 2025

Spatial Estimation Of Trophic State For Reservoir Using Ground Monitoring And Remote Sensing Data, Thong Nguyen Hoang, Van Tran Thi

Applied Environmental Research

Nutrient pollution, also known as eutrophication, is a severe environmental problem that leads to harmful algal blooms in water bodies and affects water supplies for human use. This study aims to determine the trophic state of the reservoir based on the trophic state index (TSI) calculated from ground monitoring data of Secchi depth (SD), total phosphorus (TP), and chlorophyll-a (Chl-a) obtained from 35 points in 2 survey periods during the late rainy season to early dry season 2012–2013 and May 2023. In addition, we combined remote sensing data to spatially estimate the eutrophication situation across the reservoir through correlation analysis …


Efficient Oxidation Of Methylene Blue Via Catalytic Activation Of Peroxymonosulfate Via An Engineered Δ-Feooh/Pili Nutshell Biochar Composite, Lorenz Borromeo Jan 2025

Efficient Oxidation Of Methylene Blue Via Catalytic Activation Of Peroxymonosulfate Via An Engineered Δ-Feooh/Pili Nutshell Biochar Composite, Lorenz Borromeo

Applied Environmental Research

This study introduces a novel composite catalyst formed by anchoring delta iron oxyhydroxide (δ-FeOOH) onto pyrolyzed Pili nutshell biochar via a room-temperature coprecipitation technique, marking the first application of Pili nutshell waste in advanced oxidation processes for wastewater treatment. This innovative methodology enhances catalyst dispersion and stability, facilitating the activation of peroxymonosulfate (PMS) to generate reactive sulfate radicals (SO4•–) for the degradation of methylene blue (MB), a thiazine dye commonly used in the medical field and the dye industry. Different techniques have been used to characterize synthesized composites in terms of their morphology, elemental composition, surface functional groups, and crystalline …


Assessment Of The Carbon Stock Of Trees In Selected Urban Green Spaces Of Davao City, Philippines, Daiseree Cuabo, Yves P.M. Montero, Daryl S. Salas, John P.M. Viernes Jan 2025

Assessment Of The Carbon Stock Of Trees In Selected Urban Green Spaces Of Davao City, Philippines, Daiseree Cuabo, Yves P.M. Montero, Daryl S. Salas, John P.M. Viernes

Applied Environmental Research

The combined impacts of deforestation, tree cover loss, and urbanization in urban and suburban areas significantly reduce the capacity of natural carbon sinks to sequester and store carbon. Hence, this study assessed the aboveground biomass (AGB) and carbon stock of trees in the selected green spaces of Davao City. A purposive sampling technique was employed in placing quadrats, with data collected from 27 plots categorized by size. AGB was estimated via an allometric equation, and aboveground carbon (AGC) was derived from the AGB values. A total of 358 individual trees from 25 species, 24 genera, and 13 families were documented. …


Spatial And Temporal Trends In Surface Water Quality And Pollution Sources In Ben Tre, Vietnam: A Principal Component Analysis/Factor Analysis-Based Approach, Nguyen Xuan Tong, Luu Tang Phuc Khang Jan 2025

Spatial And Temporal Trends In Surface Water Quality And Pollution Sources In Ben Tre, Vietnam: A Principal Component Analysis/Factor Analysis-Based Approach, Nguyen Xuan Tong, Luu Tang Phuc Khang

Applied Environmental Research

Surface water quality is vital for maintaining ecological health and supporting sustainable development, particularly in the Mekong Delta, Vietnam, where water is heavily utilized. However, rapid urbanization and economic activities have led to water pollution. This study assessed the spatial and temporal variations in surface water quality in Ben Tre Province from January 2022 to December 2023 using 384 samples collected across dry and rainy seasons and two zones (headwater streams and cities). The water quality index (WQI) was calculated on the basis of 15 parameters, and principal component analysis/factor analysis was applied to identify pollution sources. Five key factors …


Fabrication Of Functional Microparticles For Biological Analysis, Justin George Jan 2025

Fabrication Of Functional Microparticles For Biological Analysis, Justin George

Electronic Theses & Dissertations (2024 - present)

To better advance our knowledge of cellular behavior, development of an organism, and disease mechanisms understanding cellular heterogeneity in the functional proteome is essential. Bulk measurements across a cell population often fail to capture the variations which exist between individual cells, however single cell proteomic technology has increasingly demonstrated the characterization of cellular heterogeneity. A single cell functional proteomics assay needs to be both high-throughput and multiplexed to effectively identify biomarkers and provide a quantitative correlation to better understand the interrelationships within complex protein networks. Janus particles have the ability to be engineered to have good compatibility and stability in …


Influence Of Crabgrass Root Exudates On The Hydrocarbons Degrading Microorganisms In Crude Oil Contaminated Soil, Sinha Changsiriwatana, Kwang Mo Yang, Toemthip Poolpak, Prayad Pokethitiyook Jan 2025

Influence Of Crabgrass Root Exudates On The Hydrocarbons Degrading Microorganisms In Crude Oil Contaminated Soil, Sinha Changsiriwatana, Kwang Mo Yang, Toemthip Poolpak, Prayad Pokethitiyook

Applied Environmental Research

Understanding plant‒microbial interactions in petroleum-contaminated soil is critical for enhancing phytoremediation technology. In this study, the root exudate of crabgrass (Digitaria ciliaris) was collected hydroponically, and its dominant composition was identified via GC‒MS. A soil microcosm study was subsequently conducted to evaluate the influence of crabgrass root exudates on microbial growth, dehydrogenase activity, and biodegradation of total petroleum hydrocarbons by the petroleum-degrading bacteria Micrococcus luteus WN01 and Acinetobacter lwoffii A07. The amendment of crabgrass root exudates significantly promoted microbial degradation in both A. lwoffii A07 (47.98%) and M. luteus WN01 (62.78%), which were 8.47% and 15.78% greater than …


Macroplastic Characteristics And Assessment Of The Plastic Abundance Index (Pai) Of Beach Sediments In Prigi Bay, East Java, Indonesia, Adinda P.A. Nevandhra, Seftiawan S. Rijal, Syarifah H.J. Sari, Defri Yona Jan 2025

Macroplastic Characteristics And Assessment Of The Plastic Abundance Index (Pai) Of Beach Sediments In Prigi Bay, East Java, Indonesia, Adinda P.A. Nevandhra, Seftiawan S. Rijal, Syarifah H.J. Sari, Defri Yona

Applied Environmental Research

Macroplastics, defined as plastic debris ranging from 2.5 to 100 cm, pose significant threats to aquatic ecosystems, as they can breakdown into smaller particles. These materials are widely dispersed across marine environments, including coastal areas. This study aimed to compare and assess the abundance of macroplastics in the foreshore and backshore zones of four beaches around Prigi Bay, East Java, Indonesia, via the plastic abundance index (PAI). Macro-plastics were collected via a 5×5 m quadrat transect method. The results revealed that single-use plastics, particularly packaging and sachets, dominated both zones, accounting for 86% and 91% of the total number of …


The Use Of Machine Learning Algorithms For Water Quality Index Prediction In The Sai Gon River, Vietnam, Thuy Nguyen Thi Diem, Mai Nguyen Thi Huynh, Tra Tran Quang Jan 2025

The Use Of Machine Learning Algorithms For Water Quality Index Prediction In The Sai Gon River, Vietnam, Thuy Nguyen Thi Diem, Mai Nguyen Thi Huynh, Tra Tran Quang

Applied Environmental Research

Accurate prediction of the water quality index (WQI) lays the groundwork for integrated river basins and sustainable water resource management. Recent and accelerated advances in machine learning have led to various promising applications in water quality assessment. The present study leverages the predictive performance of several ML algorithms, including extreme gradient boosting (XGB), the gradient boosting model (GBM), support vector regression (SVR), and the radial basic function (RBF), to predict the WQI at three monitoring sites on the Sai Gon River from 2015–2019. In comparison, the results indicate that the XGB model outperforms the other models when eight parameters, including …


Effects Of Herbicides On 2,4-D-Resistant Soil Microorganisms In Maize Cultivation In Lopburi Province, Thailand, Boontarik Chimchart, Jitra Kokaew, Amnat Eamvijarn, Kanokon Bunpha, Sontaya Khamtib, Monchai Manassila, Tawatchai Inboonchuay Jan 2025

Effects Of Herbicides On 2,4-D-Resistant Soil Microorganisms In Maize Cultivation In Lopburi Province, Thailand, Boontarik Chimchart, Jitra Kokaew, Amnat Eamvijarn, Kanokon Bunpha, Sontaya Khamtib, Monchai Manassila, Tawatchai Inboonchuay

Applied Environmental Research

This study aimed to assess the impact of herbicide application on soil micro-organism density and to identify microorganisms resistant to 2,4-D-dimethyl-ammonium (2,4-D) for potential biodegradation. Research was conducted in maize plots in Lopburi Province, where 2,4-D was applied at a rate of 120 g of active ingredient per 160 m2. The soil samples were collected at various intervals: before application; 2 and 4 hours postapplication; and 1, 3, and 7 days after application. The analyses included soil property and microorganism population analyses. The results indicated that 2,4-D applications significantly increased bacteria and fungi in the treated plots compared with those …


Kinetics Of Hexavalent Chromium Adsorption And Reduction By Living Cells Of The Marine Bacterium Bacillus Cereus, Jittima Charoenpanich, Wachiraphorn Cherdchoo, Jutamas Pantab, Jariya Supakrit Jan 2025

Kinetics Of Hexavalent Chromium Adsorption And Reduction By Living Cells Of The Marine Bacterium Bacillus Cereus, Jittima Charoenpanich, Wachiraphorn Cherdchoo, Jutamas Pantab, Jariya Supakrit

Applied Environmental Research

This study identified Bacillus cereus, an efficient Cr(VI) bioreducer, isolated from marine sediment in Thailand. Batch experiments verified the complete removal of 25 mg L-1Cr(VI) from synthetic wastewater (pH 7.0) after 6 days at 37 °C, 50 rpm,and a biomass concentration of 25% (v/v) culture inoculum. The Freundlich isotherm model demonstrated the best correlation with the Cr(VI) adsorption equilibrium data in the 25–100 mg L-1concentration range (R2= 0.9831). Kinetic analyses indicated that the removal of Cr(VI) by living B. cereusfollowed a pseudo-second-order adsorption model (R2= 0.9875) and a pseudo-second-order reduction model (R2= 0.9807). The adsorption rate can be accuratelycharacterizedvia the …


Evaluation Of The Maneuverability Of An 85m Fishing Trawler (Focusing On Dynamic Stability), Chun-Ki Lee, Su-Hyung Kim Jan 2025

Evaluation Of The Maneuverability Of An 85m Fishing Trawler (Focusing On Dynamic Stability), Chun-Ki Lee, Su-Hyung Kim

Journal of Marine Science and Technology–Taiwan

Most fishing vessels are less than 100 meters in length, so IMO maneuverability standards do not apply. As a result, studies on the maneuverability of fishing vessels are considerably fewer compared to those on merchant ships. However, with technological advancements, the size of fishing vessels continues to grow, and as more fishermen are on board, accidents could lead to fatal casualties. In response, the authors determined that research on the maneuverability of fishing vessels is urgently needed. Thus, the authors conducted a maneuverability evaluation on a fisheries training vessel with the hull shape of a fishing trawler, 85 meters in …


A Hybrid Image Filtering Approach For Improving Edge Detection Of Riverbed Particles With Complex Textures, Po-Wei Lin, Hsun-Chuan Chan Jan 2025

A Hybrid Image Filtering Approach For Improving Edge Detection Of Riverbed Particles With Complex Textures, Po-Wei Lin, Hsun-Chuan Chan

Journal of Marine Science and Technology–Taiwan

The distribution of particle size in gravel-bed rivers affects the flow condition, sediment transport, and river morphology. However, conventional particle size analysis is laborious and time-consuming. To enhance the efficiency of particle size analysis, image-based methods have been widely explored, but complex particle textures increase the difficulty in identifying particle edges during image analysis. This study develops a filtering approach based on the rolling guidance filter and leverages the differences in grayscale gradients between particle edges and textures to design a guidance image tailored for the rolling guidance filter. This design enables the filter to preserve particle edges while smoothing …