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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

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

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

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

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

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

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

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

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

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 …

It’S Time To Stop Calling People "Stakeholders", Bethann Garramon Merkle, Evelyn Valdez-Ward, Priya Shukla, Skylar R. Bayer

Human–Wildlife Interactions

Although the term “stakeholder” has been widely used in science communication, recent expansion in the discourse around the negative connotations of the term necessitate that scientists and practitioners cease using the term. We discuss why this shift is necessary, how it affects our own praxis, and suggest resources for working through more respectful and just language. Looking to the science communication literature can help recalibrate terminology in positive ways.

Investigating The Thermal Stratification Patterns Of A Shallow Polymictic Boreal Shield Lake And The Effectiveness Of Models In Predicting Shallow Lake Thermal Profiles, Matthew Roberts

Theses and Dissertations (Comprehensive)

Thermal stratification is a core process of lakes which plays a critical role in shaping the ecological dynamics of lakes, influencing major processes like nutrient cycling and oxygen availability. For shallow polymictic lakes, thermal stratification patterns present some unique differences due to the complex and variable nature of these lakes. In this thesis, I examined thermal stratification in a shallow polymictic lake in northwestern Ontario during the ice-free season of 2019 to investigate the frequency, duration, and driving factors of thermal stratification. The lake underwent 146 separate stratification events, with a median duration of 2 hours per event, with a …

Using Landscape Ecology And Spatial Statistics To Examine The Impacts Of Proposed Removals To Natural Heritage System And The Agricultural System Of Ontario’S Greenbelt, Brianna Downey

Theses and Dissertations (Comprehensive)

The 2022 proposed removals from the Greater Toronto Area (GTA), Southern Ontario’s Greenbelt would have resulted in negative impacts including, reductions to the size and functionality of the Agricultural System and Natural Heritage System, which are components of protected Greenbelt area. Several removal sites were located either on or in close proximity to corridor areas of the NHS, reducing connectivity and negatively impacting the surrounding ecological area. The removal of Agricultural land primarily consisted of corn and soybeans, as well as large removals of woodland, wetland, and shrubland class areas. The removal sites on local Agricultural composition and configuration were …

Comprehensive Analysis Of Environmental Particulate Matter: Chemical Composition And Microbial Assessment, Uyen T. L. Le

Theses and Dissertations (Comprehensive)

Rapid industrialization and population growth have contributed to a decline in air quality, with particulate matter (PM) posing particular concern. PM originates from both natural and human sources and often contains toxic chemicals and microorganisms, including potential pathogens. Inhalation of PM is linked to respiratory and cardiovascular diseases, underscoring the need to characterize better its chemical and biological composition in understudied region - Waterloo, Ontario, Canada. The present thesis is a culmination of three main parts. Part 1 will describe the use of the dithiothreitol (DTT) assay to quantify the oxidative potential of PM through DTT consumption of redox-active field …

Integrating Indigenous Values And Community Strengths To Achieve Indigenous Food Sovereignty And Community Well-Being In The Ka’A’Gee Tu First Nation, Northwest Territories, Jennifer K. Temmer

Theses and Dissertations (Comprehensive)

Northern Indigenous communities face disproportionate impacts from interconnected challenges related to climate change, food security, health, and cultural preservation, that threaten traditional food systems and practices. While there is a growing recognition of the importance of community-driven solutions, existing frameworks fail to integrate Indigenous values and local priorities effectively. This research addresses this gap by exploring how the Ka’a’gee Tu First Nation (KTFN) is responding to these crises through climate change adaptation efforts focused on food system sustainability as a pathway to self-sufficiency and community well-being. To contribute to these efforts, this dissertation uses Participatory Action Research to facilitate community-driven …

Macroinvertebrate Communities And Food Web Structure In Tundra Streams Are Shaped By Substrate Size And Beaver Impoundments, Mathew K. Mervyn

Theses and Dissertations (Comprehensive)

North American beavers (Castor Canadensis) are expanding their range into the Arctic tundra as climate change drives earlier ice and snowmelt, and increased shrub cover. As ecosystem engineers, beavers build dams that alter water chemistry by creating impoundments within streams, trapping sediment and organic matter, and modifying nutrient cycling. This thesis evaluates how beaver impoundments interact with natural geomorphic variation in tundra streams and how impoundments affect tundra freshwater ecosystems in the western Canadian Arctic.

In Chapter 2, I compared water chemistry and benthic macroinvertebrate (BMI) community composition across 16 stream reaches, including those with and without beaver dams, with …

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

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

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

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

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 …

Survival And Spatial Ecology Of North American River Otters (Lontra Canadensis) In West Virginia, Laurel Marie Glover

Graduate Theses, Dissertations, and Problem Reports (ETD)

Wildlife reintroductions function to regain wildlife populations in areas where they have been extirpated or greatly diminished. One such species that has been reintroduced to several states is the North American river otter (Lontra canadensis). The West Virginia Division of Natural Resources (WVDNR) conducted a river otter reintroduction effort between 1984-1997, releasing 245 individuals into the state. The reintroduction was deemed a success with the WVDNR opening a regulated trapping season for river otters in 2011, allowing trappers to take one river otter per season. As the population has reestablished in West Virginia, several management challenges have arisen …

Carbon Sequestration Through Conservation Tillage In Sandy Soils Of Arid And Semi-Arid Climates: A Meta-Analysis, Samantha Lynn Colunga, Leila Wahab, Alejandro Fierro-Cabo, Engil Isadora Pujol Pereira

School of Earth, Environmental, & Marine Sciences Faculty Publications

Highlights

• Under CST, SOC increased by 12.74 ± 1.46 % in sandy soils with 5 of the 6 practices contributing to this rise.
• SOC increased up to 15 years post-CST conversion, but more research is needed to assess long-term effects.
• SOC increased by 13% in soils with over 56% sand content under CST.
• SOC increased by 15% in the 0-20 cm depth under CST, with no significant increase at greater depths.
• SOC increased under CST when nitrogen was applied at rates up to 100 kg N ha⁻¹.

Abstract

This meta-analysis assessed soil organic carbon (SOC) percent changes in sandy soils, …

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 …

Nesting Population Trend Of The Leatherback Sea Turtle In Bocas Del Toro Province And Comarca Ngäbe-Buglé, Panama For The Period 2002–2022, Sonia Gutiérrez Parejo, Susan E. Piacenza, Raúl García, Cristina Ordóñez, Roldán A. Valverde

School of Earth, Environmental, & Marine Sciences Faculty Publications

Sea turtle biologists have made sustained efforts to understand the global status of leatherback sea turtle populations. However, despite progress in assessments, demographics, and ecology, key uncertainties persist in tracking leatherback population trends. Trend analyses have historically focused on nesting beaches, with nest counts providing a widely used index for population abundance. Here, we analysed 20 years of annual nest abundance at four main nesting beaches (Soropta, Bluff, Playa Larga and Chiriquí) in Bocas del Toro province and the Comarca Ngäbe-Buglé, Panama, which constitute the largest nesting leatherback sea turtle population in Central America. We conducted daily nest counts during …

Investigating The Biology, Hypovirulence, And Pathogenicity Of Three Canker-Causing Phytopathogenic Fungi In The Cryphonectriaceae And Cytosporaceae On American Chestnut (Castanea Dentata) And Oaks (Quercus Spp.) In The Eastern U.S., Danielle N. Mikolajewski

Graduate Theses, Dissertations, and Problem Reports (ETD)

American chestnut (Castanea dentata) and various oak species (Quercus spp.) are impacted by several economically important canker pathogens in the fungal order Diaporthales, namely Cryphonectria parasitica and Endothia gyrosa (Cryphonectriaceae). Cytospora canker caused by several closely related fungi in the fungal genera Cytospora and Valsa (Cytosporaceae) have also been implicated in causing canker diseases of Quercus and Castanea in Asia, Europe and North America. The impacts of C. parasitica on American chestnut have been exhaustively studied and it’s impacts on various oak hosts have also been broadly investigated and reported. Endothia gyrosa has …

The Role Of Floodplain Complexity In Wood Turtle Habitat Use, Laura S. Deming

Antioch University Dissertations & Theses

Wood turtles occupy cold, low-gradient riverine habitat throughout the northeastern United State and southeastern Canada. Stream alterations, such as dams, channel straightening, and floodplain development have diminished the natural hydrologic and sedimentation regimes that result in complex channel and floodplain geomorphology. Studies throughout the species’ range have quantified many aspects of their habitat, but none have quantified components of geomorphology of wood turtle sites. The goal of this study was to explore the role of stream channel and floodplain geomorphology in wood turtle habitat use, with specific objectives to (1) quantify components of stream channel and floodplain geomorphic complexity, (2) …

21st-Century Stewardship: Infusing Environmental Education With Global Citizenship, Ava Y. Goodale

Antioch University Dissertations & Theses

In today's interconnected world, where socioecological issues transcend political borders, integrating environmental stewardship education with global citizenship education offers valuable opportunities for student empowerment. The goal of this multi-article dissertation was to conceptualize and operationalize 21st-century stewardship in educational settings. Twenty-first-century stewardship is a pedagogical approach that recognizes the limitations of environmental stewardship education as it is traditionally taught and is defined in Chapter II as an updated stewardship model that is infused with global citizenship’s multiscalar perspectives, global compacts, and layered identities to achieve its maximum impact in our interconnected world. This goal was first accomplished in Chapter II …

Dam It All: A Multi-Scalar Investigation Into The Ecological Role And Function Of Beaver Dams, Kenneth Larsen

Dissertations, Master's Theses and Master's Reports

The central theme of this dissertation is ecological scaling, which examines how small, localized features, such as beaver ponds, contribute to large-scale watershed processes and how different modeling approaches at various scales reveal distinct insights. Through a combination of probabilistic modeling and high-resolution empirical research, this work demonstrates that small ponded systems, particularly those created by beavers (Castor canadensis), serve as critical biogeochemical control points, whose contributions to sediment and nutrient dynamics have been historically underestimated.

In Chapter 1, I contextualize this research within the broader fields of freshwater ecology, watershed modeling, and ecological restoration. I introduce the …

Coupling Remote Sensing And Modelling To Monitor The Spatial Distribution And Trends Of Surface Temperature And Ice Thickness On Sub-Arctic Lakes, Gifty Attiah

Theses and Dissertations (Comprehensive)

Lake surface temperature (LST), lake ice thickness (LIT), and lake ice phenology (LIP) play significant roles in the diverse regional processes of freshwater in cold regions. They offer direct indications of regional weather and climate conditions, and their interactions with the atmosphere impact climate processes. Furthermore, lake ice is valuable to northern communities, such as those in the Northwest Territories (NWT). Ice roads, including the longest ice road in the NWT, spanning over 80 lakes, are constructed during winter to haul goods to and from industrial establishments (e.g., mines) and for travel within and between communities. A significant challenge to …