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Metal Contamination In Household Dust And Their Health Risk Assessment: A Study In Two Malaysian Cities, Xin Yi Lim, Ting Fang Lye, Joo Hui Tay Jan 2024

Metal Contamination In Household Dust And Their Health Risk Assessment: A Study In Two Malaysian Cities, Xin Yi Lim, Ting Fang Lye, Joo Hui Tay

Applied Environmental Research

Investigating the composition of household dust can provide crucial insights into potential environmental and health implications. This study aimed to determine the concentration of selected metals in 30 household floor dust samples collected from two cities in Peninsular Malaysia, namely Melaka and Butterworth. The samples were collected using nylon socks attached to a vacuum cleaner nozzle during January-February 2021. All samples were sieved through a 200-µm sieve, acid-digested with aqua regia, and analyzed using inductively coupled plasma mass spectrometry (ICP-MS). Mean metal concentrations decreased in the order of Fe>Al>Mg>Zn>Mn>Ba>Cu>Cr>Pb. Cd was not …


Unveiling Long-Term Impacts Of Forest Cover Changes And Carbon Storage Assessment In Nan Province, Thailand, Jiratiwan Kruasilp, Sura Pattanakiat, Siam Lawawirojwong, Thamarat Phutthai, Poonperm Vardhanabindu, Warinthorn Kiadtikornthaweeyot Evans, Anne Jacquine Jan 2024

Unveiling Long-Term Impacts Of Forest Cover Changes And Carbon Storage Assessment In Nan Province, Thailand, Jiratiwan Kruasilp, Sura Pattanakiat, Siam Lawawirojwong, Thamarat Phutthai, Poonperm Vardhanabindu, Warinthorn Kiadtikornthaweeyot Evans, Anne Jacquine

Applied Environmental Research

Forests serve as carbon sink by storing and sequestrating carbon dioxide from the atmosphere. Forest cover loss adversely affects communities by increasing risks to the shortage of carbon storage. This study provides a comprehensive understanding of forest fragmentation and assessment of forest cover changes impacts on carbon storage over Nan province during 1990 to 2019. Spatial and temporal patterns were explored using landscape metrics analysis. Forest areas declined 10.69% over 30 years using random forest classifier based on Google Earth Engine platform, with an overall accuracy of 97.10%. The highest rate of forest cover changes was 5.27% (2010 to 2014), …


Minimization The Chemical Oxygen Demand (Cod) Content In Tannery Wastewater Using Activated Carbon From Spent Tea Leaves, Kanish Fatama, Nasifa Akter, Badhan Saha, Nur -E- Alam Md., Shimul Chakma Jan 2024

Minimization The Chemical Oxygen Demand (Cod) Content In Tannery Wastewater Using Activated Carbon From Spent Tea Leaves, Kanish Fatama, Nasifa Akter, Badhan Saha, Nur -E- Alam Md., Shimul Chakma

Applied Environmental Research

Water pollution from tannery wastewater is a serious environmental issue. This study aimed to investigate the potential of spent tea leaves as activated carbon (AC) to minimize chemical oxygen demand (COD) of tannery effluent. To determine the best conditions for minimizing COD, a batch adsorption process was conducted, involving various factors such as different adsorbent dosages (ranging from 1 to 11 gm L-1), contact time (30 to150 min), and pH values (ranging from 3 to 11). The characterization was done by Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM). The outcomes of this study demonstrated that using 1.5 M …


Path Analysis Of The Relationship Between Diarrhea, Climate And Environmental Variables In Province Of West Nusa Tenggara-Indonesia, Khadijah Azhar, Ika Dharmayanti, Dwi Hapsari Tjandrarini, Bambang Wispriyono Jan 2024

Path Analysis Of The Relationship Between Diarrhea, Climate And Environmental Variables In Province Of West Nusa Tenggara-Indonesia, Khadijah Azhar, Ika Dharmayanti, Dwi Hapsari Tjandrarini, Bambang Wispriyono

Applied Environmental Research

Diarrhea is a major cause of morbidity and mortality, particularly in West Nusa Tenggara Province, Indonesia, due to certain factors. Therefore, this study aims to examine the influence of climate, economic status, demographic, water, sanitation, and hygiene factors on diarrhea. The study procedures were carried out using an ecological design that focused on the characteristics of the sample population. The unit of analysis was districts/cities, where data on diarrhea cases from 2017–2020 were used, along with other variables in the same period. The dependent variable was the number of diarrhea cases per month, while the independent variables included average temperature, …


Effective Microorganisms (Em) As Bioremediation Agent Of Profenofos Pesticide Residue In Vegetable Farm Soil From Benguet Province, Philippines, Maylowen P. Lumayna, Paulina A. Bawingan Jan 2024

Effective Microorganisms (Em) As Bioremediation Agent Of Profenofos Pesticide Residue In Vegetable Farm Soil From Benguet Province, Philippines, Maylowen P. Lumayna, Paulina A. Bawingan

Applied Environmental Research

Effective microorganisms (EM) have shown remarkable adaptability and have been used in agriculture and environmental management. This study intended to provide insights into the effectiveness of EM technology in rehabilitating soils contaminated with pesticides. Specifically, the study aimed to determine the efficiency of EM in breaking down the profenofos component of Selecron® 500 EC pesticide in a controlled condition. Results show that the initial profenofos (17.2 mg kg-1) degraded in the control and experimental groups by 94.19% and 96.45%, respectively, over a 21-day laboratory experiment. EM-treated soil samples showed a significant difference from untreated samples, as revealed in the Kruskal-Wallis …


Typhoon Damage Assessment Of Natural And Planted Mangroves In Bais Bay, Negros Oriental, Philippines, Myron Gavriel F. Baring, Pablina L. Cadiz Jan 2024

Typhoon Damage Assessment Of Natural And Planted Mangroves In Bais Bay, Negros Oriental, Philippines, Myron Gavriel F. Baring, Pablina L. Cadiz

Applied Environmental Research

Category 5 Typhoon Odette, internationally known as Rai, devastated the Central Philippines in December 2021, causing immense damage to the country’s infrastructure, agriculture, and ecosystems. Coastal vegetative ecosystems, which include mangroves, are exposed to strong wind and wave energy during extreme weather events. Considering their importance in providing a myriad of ecosystem services to coastal communities, the post-typhoon assessment of mangroves will serve as a guide to future rehabilitation efforts.  On August 13 and 14, 2024, 8 months after Typhoon Odette, the community structure characteristics (species composition, stem density, basal area, and regeneration potential) and damage severity of planted and …


Unraveling The Effects Of Arbuscular Mycorrhizal Fungi On Plant Growth, Nutrient Content, And Heavy Metal Accumulation In The Contaminated Soil: A Meta-Analysis, Bela Putra, Anuraga Jayanegara, Irwan Susanto Jan 2024

Unraveling The Effects Of Arbuscular Mycorrhizal Fungi On Plant Growth, Nutrient Content, And Heavy Metal Accumulation In The Contaminated Soil: A Meta-Analysis, Bela Putra, Anuraga Jayanegara, Irwan Susanto

Applied Environmental Research

This study evaluated the effects of arbuscular mycorrhizal fungi (AMF) on plant growth, nutrient uptake, and heavy metal accumulation on polluted land using a meta-analysis approach. Data from 33 relevant studies were selected based on inclusion criteria, specifically articles in English, observational research, and investigating the role of AMF in plant growth and productivity on polluted land. The results showed that plants inoculated with AMF experienced significant accumulation of heavy metals in roots, such as Pb (p<0.01), Ni (p<0.01), Cr (p<0.01), Mn (p<0.05), Fe (p<0.05), and As (p<0.05). The AMF significantly reduced the accumulation of heavy metals such as Cr, Ni, Fe, and Cu on the upper part of fodder forage (p<0.01). Forage growth was also enhanced due to AMF. The AMF greatly increased the fresh weight, length, and phosphorus (P) content of fodder forage roots (p<0.01). It also increased the plant's biomass, fresh weight, dry weight, height, nitrogen (N), phosphorus (P), and potassium (K) contents (p<0.01). In conclusion, AMF is important in increasing plant growth, nutrient uptake and reducing heavy metal accumulation in forage on polluted land.


Analyzing Climate Change Status Through Evaluating Trend Of Temperature And Rainfall And Predicting Future Climate Change Status At Lake Tana Basin, Tesfaye Bayu Zeleke, Tri Retnaningsih Soeprobowati, Solomon Adissu, Meseret Abatechanie Jan 2024

Analyzing Climate Change Status Through Evaluating Trend Of Temperature And Rainfall And Predicting Future Climate Change Status At Lake Tana Basin, Tesfaye Bayu Zeleke, Tri Retnaningsih Soeprobowati, Solomon Adissu, Meseret Abatechanie

Applied Environmental Research

The trends of temperature and rainfall are critical indicators of climate change within a certain area. However, the existence of climate change is not locally understood in most parts of the world. This research aims to analyze the trend of temperature and rainfall in the Lake Tana Sub-basin as a means to understand the current and future status of climate change. The trends of temperature and rainfall were analyzed using the modified Mann-Kendall trend test, while the autoregressive integrated moving average model (ARIMA) was used to predict future temperature and rainfall. The findings reveal that monthly temperatures show a significant …


Groundwater Recharge And Surface Runoff Modeling Response To Land Use And Land Cover Dynamics In A Mae Wong Watershed Of Thailand, Banchongsak Faksomboon, Pranee Lertkaeo, Bunchongsri Phunlao Jan 2024

Groundwater Recharge And Surface Runoff Modeling Response To Land Use And Land Cover Dynamics In A Mae Wong Watershed Of Thailand, Banchongsak Faksomboon, Pranee Lertkaeo, Bunchongsri Phunlao

Applied Environmental Research

This study aims to develop efficient management strategies and assess the spatiotemporal dynamics of land use and land cover (LULC) on surface runoff modeling response dynamics for the long-term sustainability of watersheds. The soil and water assessment tool (SWAT) model was used to evaluate the LULC dynamics on GRSR in the Mae Wong Watershed (MWW) of Thailand. Using Landsat images, three different LULC maps (2011, 2021, and 2031) were created using the cellular automata markov chain (CA-Markov) model, and TerrSet 2020 geospatial monitoring and modeling software. In the overall MWW, the forestland has undergone deforestation and decreased by 2.10% of …


An Optimal Culture Medium For Laccase Production And Sugar Cane Vinasse Biotreatment With Trametes Villosa Using Plackett-Burman And Central Composite Designs, Rosa Elena Caballero, Víctor Jiménez, Mónica Miranda, Dalys Rovira, Guillermo Branda, Juana Ramos Chue De Pérez Jan 2024

An Optimal Culture Medium For Laccase Production And Sugar Cane Vinasse Biotreatment With Trametes Villosa Using Plackett-Burman And Central Composite Designs, Rosa Elena Caballero, Víctor Jiménez, Mónica Miranda, Dalys Rovira, Guillermo Branda, Juana Ramos Chue De Pérez

Applied Environmental Research

The optimal conditions for laccase production and vinasse biotreatment with a native strain of Trametes villosa were determined by a screening-optimization approach. Eleven factors including nutrient concentration, vinasse dilution (%v/v), inoculum volume, carbon to nitrogen ratio and initial pH, were investigated for their effects on laccase activity applying the Plackett-Burman screening design. The selected factors were optimized using a central composite design, and then evaluated on a vinasse biotreatment experiment. The factors that contributed the most to the enzymatic activity were the concentrations of MgSO4∙7H2O (A), FeSO4∙7H2O (B) and CuSO4∙5H2O (C), alongside initial pH.  After 10 days, laccase activity was …


Multi-Class Waste Classification Using Convolutional Neural Network, Yanfahmi Rayhan, Achmad Pratama Rifai Jan 2024

Multi-Class Waste Classification Using Convolutional Neural Network, Yanfahmi Rayhan, Achmad Pratama Rifai

Applied Environmental Research

This study explores a method of waste classification using deep learning, specifically employing the Convolutional Neural Network (CNN). This research involves the creation of a unique dataset, a hybrid of publicly accessible data and a newly compiled collection of images across 13 waste classes: paper, glass, wood, metal, clothes, PCB e-waste, non-PCB e-waste, PET, HDPE, LDPE, PP, PVC, and PS. The development of the CNN model was approached in two ways: transfer learning and full learning. In the transfer learning approach, two pre-trained models, MobileNetV2 and DenseNet121, were utilized. While in the full learning approach, the architecture is constructed using …


Exploring Google Earth Engine, Machine Learning, And Gis For Land Use Land Cover Change Detection In The Federal Capital Territory, Abuja, Between 2014 And 2023, Akus Kingsley Okoduwa, Chika Floyd Amaechi Jan 2024

Exploring Google Earth Engine, Machine Learning, And Gis For Land Use Land Cover Change Detection In The Federal Capital Territory, Abuja, Between 2014 And 2023, Akus Kingsley Okoduwa, Chika Floyd Amaechi

Applied Environmental Research

This study aims to visualize various land use land cover (LULC) classes, estimate the net change in LULC types between the years 2014 and 2023, and use transition mapping to track LULC transitions within waterbody, vegetation, bareland, and buildup to better understand how land use types change from one another. Google Earth Engine (GEE), Random Forest (RF), and Geographic Information System (GIS) were used for LULC classification and change detection. The dataset employed for this study is Landsat-8 with 30 m resolution, and four land cover classes, which include waterbody, vegetation, bareland, and buildup, were classified for this study using …


Using Neural Networks For Sustainable Land Use Prediction In Sumbawa Regency, Indonesia, Muhammad Ramdhan, Rudhy Akhwady, Taslim Arifin, Dini Purbani, Yulius -, Dino G. Pryambodo, Rinny Rahmania, Olivia Maftukhaturrizqoh, Abdul Asyiri, Syamsul Hidayat, Arya Ningsih, Sadad - Jan 2024

Using Neural Networks For Sustainable Land Use Prediction In Sumbawa Regency, Indonesia, Muhammad Ramdhan, Rudhy Akhwady, Taslim Arifin, Dini Purbani, Yulius -, Dino G. Pryambodo, Rinny Rahmania, Olivia Maftukhaturrizqoh, Abdul Asyiri, Syamsul Hidayat, Arya Ningsih, Sadad -

Applied Environmental Research

Agriculture is vital to Sumbawa Regency's economy, with key activities such as rice cultivation, corn production, onion farming, and cattle rearing. This study applies artificial neural networks (ANN) to predict land cover changes, focusing on agricultural land expansion. Using land cover datasets from ESRI, digital elevation model, and topographical maps, we analyzed land cover changes from 2017 to 2023 and generated future projections for 2050 with the MOLUSCE plugin in qGIS. The predictive model achieved an 85% accuracy rate when comparing 2023 actual data with predictions. Results indicate a significant increase in agricultural land cover by 2050. The key finding …


Establishing Optimal Machine Learning Models For Monitoring Water Quality In Vietnam’S Upper Ma River, Thanh-Son Ngo, Duc-Loc Nguyen Jan 2024

Establishing Optimal Machine Learning Models For Monitoring Water Quality In Vietnam’S Upper Ma River, Thanh-Son Ngo, Duc-Loc Nguyen

Applied Environmental Research

This study aims to establish the optimal regression model for predicting total suspended solids (TSS) and Turbidity based on in situ data and spectral regions of Sentinel-2 images. Various machine learning models were evaluated, including Multilayer Perceptron Regression (MLPR), Random Forest Regression (RFR), AdaBoost Regression (ABR), Multiple Linear Regression (MLR), and K-Nearest Neighbors Regression (KNNR). These models were applied to different band combinations of spectral regions: visible (VIS), near-infrared (NIR), shortwave-infrared (SWIR), VIS+NIR (VNIR), and VIS+NIR+SWIR (VNIR+SWIR). The study results revealed that the MLR model, while not the best performer during training (R2 = 0.89 for TSS and R2 = …


Assessment Of Potential Impacts Of Climate Change On Hydrology And Water Resource Availability In The Passaic River Basin, New Jersey, Felix Oteng Mensah Jan 2024

Assessment Of Potential Impacts Of Climate Change On Hydrology And Water Resource Availability In The Passaic River Basin, New Jersey, Felix Oteng Mensah

Theses, Dissertations and Culminating Projects

Streamflow dynamics in a basin is known to be a major driver of available water resources. In the context of climate change, it is expected that global warming will accelerate the global hydrologic cycle, which will drive more intense floods and droughts leading to changes in streamflow and water resource availability. Most researchers agree that the amount and intensity of precipitation have a direct impact on runoff. Yet, there is no consensus as to how warming can affect streamflow. Evapotranspiration (ET) plays a crucial role here. However, there is a shortage of real-world observations on it. And yet, ET is …


Simulation Of Wave Propagation In Granular Particles Using A Discrete Element Model, Syed Tahmid Hussan Jan 2024

Simulation Of Wave Propagation In Granular Particles Using A Discrete Element Model, Syed Tahmid Hussan

College of Graduate Studies: Theses & Dissertations

The understanding of Bender Element mechanism and utilization of Particle Flow Code (PFC) to simulate the seismic wave behavior is important to test the dynamic behavior of soil particles. Both discrete and finite element methods can be used to simulate wave behavior. However, Discrete Element Method (DEM) is mostly suitable, as the micro scaled soil particle cannot be fully considered as continuous specimen like a piece of rod or aluminum. Recently DEM has been widely used to study mechanical properties of soils at particle level considering the particles as balls. This study represents a comparative analysis of Voigt and Best …


Identifying Accessibility Improvement Opportunities For Global Environmental Communication Websites, Alicia Mason, Josh Compton, Sakshi Bhati Jan 2024

Identifying Accessibility Improvement Opportunities For Global Environmental Communication Websites, Alicia Mason, Josh Compton, Sakshi Bhati

Faculty Submissions

Digital environmental information presented with low web accessibility reduces parti-cipation in environmental advocacy and information seeking behaviors for many people with disabilities, creating a consequential digital divide. We use WEB AIM computer automated analysis of web accessibility to assess the general accessibility of online environmental communication messages. Results show 95.3% of the popular websites in our sample had indicators of potentially critical accessibility errors. Our findings highlight the importance of addressing digital environmental information accessibility shortcomings so that educational, informational and persuasive environ-mental messages can increase environmental literacy of vulnerable populations and help to bridge the digital divide.


Two-Stage Thermophilic Anaerobic Digestion Of Rice Straw And Vegetable Residues For Biogas Production, Piyathida Khantibongse Jan 2024

Two-Stage Thermophilic Anaerobic Digestion Of Rice Straw And Vegetable Residues For Biogas Production, Piyathida Khantibongse

Chulalongkorn University Theses and Dissertations (Chula ETD)

Renewable energy is crucial for meeting global energy needs while protecting the environment. Unlike fossil fuels, renewable sources like solar, wind, and biomass are sustainable and reduce greenhouse gas emissions. Biogas production, a vital part of biomass energy, converts organic waste into clean fuel through anaerobic digestion. This process generates energy, manages waste, reduces landfill use, and cuts methane emissions, promoting sustainability and energy independence. This study investigates the two-stage thermophilic anaerobic digestion of rice straw and vegetable residues for biogas production, focusing on the effects of different pretreatment methods, optimal mixing ratios, and organic loadings. The research aims to …


Using Environmental Dna Methods For Estimating Juvenile Chinook Salmon Abundance, Jacqueline Marie Bridegum Jan 2024

Using Environmental Dna Methods For Estimating Juvenile Chinook Salmon Abundance, Jacqueline Marie Bridegum

Cal Poly Humboldt theses and projects

In the Central Valley of California, stocks of Chinook Salmon are declining, and two out of the four ecotypes of Chinook Salmon within the Sacramento River system are federally listed. A monitoring network has been developed to estimate the abundances of downstream migrating Chinook Salmon smolts, but there is high uncertainty in these estimates due to low catch rates. Environmental DNA (eDNA) monitoring, which involves capture of genetic material that organisms release into their surrounding environment, has shown promise for estimating abundance of salmonids and could complement existing monitoring efforts and potentially reduce uncertainty in abundance estimates. This research project …


Brown Thrasher (Toxostoma Rufum) Habitat Preferences In Pine Barrens, Shrublands, And Agricultural Areas In New England, Alec Woolf Jan 2024

Brown Thrasher (Toxostoma Rufum) Habitat Preferences In Pine Barrens, Shrublands, And Agricultural Areas In New England, Alec Woolf

Antioch University Dissertations & Theses

Early successional habitat and related species are in decline in the Northeastern United States. One species of shrubland bird that is declining in the northeast is the Brown Thrasher, considered a species of conservation concern in several states such as New Hampshire, Rhode Island, Connecticut, New York, Vermont, and New Jersey. However, few studies have focused on examining Brown Thrasher habitat preferences. The purpose of this study was to evaluate Brown Thrasher associations with early successional habitat adjacent to farmland, within deciduous forests, and within pine barrens. I conducted systematic point count surveys with playback to assess thrasher occupancy and …


Widespread Crab Burrows Enhance Greenhouse Gas Emissions From Coastal Blue Carbon Ecosystems, Kai Xiao, Yuchen Wu, Feng Pan, Yingrong Huang, Hebo Peng, Meiqing Lu, Yan Zhang, Hailong Li, Yan Zheng, Chunmiao Zheng, Yan Liu, Nengwan Chen, Leilei Xiao, Guangxuan Han, Yasong Li, Pei Xin, Ruili Li, Bochao Xu, Faming Wang, Joseph J. Tamborski, Alicia M. Wilson, Daniel M. Alongi, Isaac R. Santos Jan 2024

Widespread Crab Burrows Enhance Greenhouse Gas Emissions From Coastal Blue Carbon Ecosystems, Kai Xiao, Yuchen Wu, Feng Pan, Yingrong Huang, Hebo Peng, Meiqing Lu, Yan Zhang, Hailong Li, Yan Zheng, Chunmiao Zheng, Yan Liu, Nengwan Chen, Leilei Xiao, Guangxuan Han, Yasong Li, Pei Xin, Ruili Li, Bochao Xu, Faming Wang, Joseph J. Tamborski, Alicia M. Wilson, Daniel M. Alongi, Isaac R. Santos

OES Faculty Publications

Fiddler crabs, as coastal ecosystem engineers, play a crucial role in enhancing biodiversity and accelerating the flow of material and energy. Here we show how widespread crab burrows modify the carbon sequestration capacity of different habitats across a large climatic gradient. The process of crab burrowing results in the reallocation of sediment organic carbon and humus. Crab burrows can increase more greenhouse gases emissions compared to the sediment matrix (CO2: by 17-30%; CH4: by 49-141%). Straightforward calculations indicate that these increased emissions could offset 35-134% of sediment carbon burial in these two ecosystems. This research highlights the complex interactions between …


Investigating The Relationship Between Inherited Geologic Framework And Saltwater Intrusion On St. Catherines Island, Georgia, Juliet Talaber, Jacque Kelly, Robert Vance Jan 2024

Investigating The Relationship Between Inherited Geologic Framework And Saltwater Intrusion On St. Catherines Island, Georgia, Juliet Talaber, Jacque Kelly, Robert Vance

Honors College Theses

Since the late 1800s, the oldest cities on the Georgia coast have been withdrawing water from the confined Floridan Aquifer System. As the population has grown, a cone of depression has formed extending from Savannah, GA to St. Catherines Island, GA, a barrier island 50 km southeast of Savannah. On St. Catherines Island, the cone of depression has reversed the lateral and horizontal groundwater flow gradients causing saltwater intrusion into the Upper Floridan Aquifer from the Lower Floridan Aquifer through joints, faults, or solution collapse features. Previous studies from the southern and central areas of the island have found evidence …


Mapping With The Land: Co-Developing A Cumulative Impact Monitoring And Land Stewardship Framework With Sambaa K’E First Nation, Northwest Territories, Canada, Michael S. Mcphee Jan 2024

Mapping With The Land: Co-Developing A Cumulative Impact Monitoring And Land Stewardship Framework With Sambaa K’E First Nation, Northwest Territories, Canada, Michael S. Mcphee

Theses and Dissertations (Comprehensive)

Across the Northwest Territories (NWT), Canada, Indigenous populations are striving to achieve effective environmental protection, whilst navigating complex methods, policies, and research relationships within co-management contexts. This thesis seeks to identify how differing cultural systems, environmental change, and fractured partnerships may be unified to align with the needs of the Sambaa K’e First Nation (SKFN), a remote Dehcho Dene community. Indigenous methodologies guided co-development of research questions with SKFN leadership which yielded objectives a) develop a GIS-based method to manage, organize and mobilize cultural and environmental data; b) develop a new stewardship monitoring procedure so that users can apply the …


Examining Seasonality Of Zooplankton Communities And Water Quality In Yellowknife Area Lakes, Northwest Territories, Nicole Andreola Jan 2024

Examining Seasonality Of Zooplankton Communities And Water Quality In Yellowknife Area Lakes, Northwest Territories, Nicole Andreola

Theses and Dissertations (Comprehensive)

Frame Lake, located in Yellowknife, Northwest Territories, is one of the city's main attractions. Unfortunately, urbanization and eutrophication have led to a decline in water quality in the lake. Eutrophication has caused a buildup of organic matter in sediments on the bottom of the lake, which can cause a high oxygen demand when processed by aerobic bacteria. Dissolved oxygen levels are high during the summer, but ice shields the lake from gas exchange with the atmosphere, leading to winter anoxia. This oxygen depletion makes it impossible for sensitive aquatic life, such as fish, to survive in the lake over the …


Impacts Of Wildfire On Subcanopy Energy Balance, Thermal Regime, And Permafrost Stability In Peat Plateaus At Scotty Creek, Canada, Maude Auclair Jan 2024

Impacts Of Wildfire On Subcanopy Energy Balance, Thermal Regime, And Permafrost Stability In Peat Plateaus At Scotty Creek, Canada, Maude Auclair

Theses and Dissertations (Comprehensive)

The stability of permafrost in peatland-dominated regions of northwestern Canada is compromised by ongoing climate warming and increased wildfire activity. This study examines an 8-year record of changes to the surface and subsurface properties of a peat plateau following a low-severity wildfire that occurred in 2014 in a region of thawing, discontinuous permafrost. This is accomplished by comparing the burned portion of a peat plateau to two unburned control sites, one of which is the unburned portion of the same plateau that was affected by the fire. Net radiation was not significantly different one year following the wildfire but became …


Plasmid-Borne Biosynthetic Gene Clusters Within A Permanently Stratified Marine Water Column, Paraskevi Mara, David Geller-Mcgrath, Elizabeth A. Suter, Gordon T. Taylor, Maria G. Pachiadaki, Virginia P. Edgcomb Jan 2024

Plasmid-Borne Biosynthetic Gene Clusters Within A Permanently Stratified Marine Water Column, Paraskevi Mara, David Geller-Mcgrath, Elizabeth A. Suter, Gordon T. Taylor, Maria G. Pachiadaki, Virginia P. Edgcomb

BCES: Faculty Publications

Plasmids are mobile genetic elements known to carry secondary metabolic genes that affect the fitness and survival of microbes in the environment. Well-studied cases of plasmidencoded secondary metabolic genes in marine habitats include toxin/antitoxin and antibiotic biosynthesis/resistance genes. Here, we examine metagenome-assembled genomes (MAGs) from the permanently-stratified water column of the Cariaco Basin for integrated plasmids that encode biosynthetic gene clusters of secondary metabolites (smBGCs). We identify 16 plasmid-borne smBGCs in MAGs associated primarily with Planctomycetota and Pseudomonadota that encode terpenesynthesizing genes, and genes for production of ribosomal and non-ribosomal peptides. These identified genes encode for secondary metabolites that are …


Geoelectrical And Hydrochemical Characterization Of Submarine Groundwater Discharge In Florida Bay, Ifeanyi Emmanuel Eze Jan 2024

Geoelectrical And Hydrochemical Characterization Of Submarine Groundwater Discharge In Florida Bay, Ifeanyi Emmanuel Eze

College of Graduate Studies: Theses & Dissertations

Florida Bay, situated at the southern tip of Everglades National Park and underlain by the Miami Limestone formation, is an ecosystem of global significance. Over the past century, the bay has faced threats such as droughts, seagrass mortality, and hypersalinity. Despite various studies and management efforts, the dynamics of submarine groundwater discharge (SGD) in the region remain underexplored. Given that SGD plays a significant role in the chemical dynamics of coastal ecosystems, it warrants thorough investigation. This study aims to characterize the spatial and temporal patterns of SGD in Florida Bay by surveying three basins – Rankin, Whipray, and Rabbit …


Nitrate Contamination In Two California Groundwater Basins: What Creates Disparities?, Catherine Protiva Jan 2024

Nitrate Contamination In Two California Groundwater Basins: What Creates Disparities?, Catherine Protiva

Scripps Senior Theses

Nitrate contamination is a major problem within California groundwater basins. A form of nitrogen, nitrates leach into groundwater aquifers from the surface where they remain for many decades. The most common source for the contaminant is agricultural sources like nitrogen fertilizer. Consequently, the problem is concentrated in regions of the state with a history of large-scale agricultural production. When water is pulled from contaminated basins and used as drinking water, the nitrates can cause serious negative health consequences, most commonly methemoglobinemia, also known as blue baby syndrome. In this thesis, I will examine what factors contribute to a region’s ability …


Evaluating Road Environment Factors Impacting Cyclist Safety In Dublin City Using Geospatial Solutions, Niamh O' Reilly Jan 2024

Evaluating Road Environment Factors Impacting Cyclist Safety In Dublin City Using Geospatial Solutions, Niamh O' Reilly

Doctoral

Police Collision Reports (PCRs) are used as a measure of road safety but are subject to under reporting and biased to collisions involving motorised vehicles or serious injury outcomes. Understanding the extent and nature of cycling safety and how the road environment contributes to these requires detailed quality data on cyclist collisions. Hospital records, insurance claim records and travel diaries are frequently used to supplement these but provide little or no information about the road environment, particularly its location. This research investigates how effective alternative georeferenced bicycle safety data sources examined through a geospatial lens can address road safety issues …


Comparison Of Test Performance Of A Conventional Pcr And Two Field-Friendly Tests To Detect Coxiella Burnetii Dna In Ticks Using Bayesian Latent Class Analysis, Maureen W. Kamau, Carmel Witte, Wynand Goosen, Mathew Mutinda, Jandouwe Villinger, Dennis Getange, Rua Khogali, Michael E. Von Fricken, Eric Maurice Fèvre, Dawn Zimmerman, Yvonne Marie Linton, Michele Miller Jan 2024

Comparison Of Test Performance Of A Conventional Pcr And Two Field-Friendly Tests To Detect Coxiella Burnetii Dna In Ticks Using Bayesian Latent Class Analysis, Maureen W. Kamau, Carmel Witte, Wynand Goosen, Mathew Mutinda, Jandouwe Villinger, Dennis Getange, Rua Khogali, Michael E. Von Fricken, Eric Maurice Fèvre, Dawn Zimmerman, Yvonne Marie Linton, Michele Miller

All Peer-Reviewed Publications

Introduction: Coxiella burnetii (C. burnetii)-infected livestock and wildlife have been epidemiologically linked to human Q fever outbreaks. Despite this growing zoonotic threat, knowledge of coxiellosis in wild animals remains limited, and studies to understand their epidemiologic role are needed. In C. burnetii-endemic areas, ticks have been reported to harbor and spread C. burnetii and may serve as indicators of risk of infection in wild animal habitats. Therefore, the aim of this study was to compare molecular techniques for detecting C. burnetii DNA in ticks. Methods: In total, 169 ticks from wild animals and cattle in wildlife conservancies in northern Kenya …