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Full-Text Articles in Engineering

Examining The Corn Seedling Emergence–Temperature Relationship For Recent Hybrids: Insights From Experimental Studies, Sahila Beegum, Charles Hunt Walne, Krishna N. Reddy, Vangimalla Reddy, Kambham Raja Reddy Oct 2023

Examining The Corn Seedling Emergence–Temperature Relationship For Recent Hybrids: Insights From Experimental Studies, Sahila Beegum, Charles Hunt Walne, Krishna N. Reddy, Vangimalla Reddy, Kambham Raja Reddy

Nebraska Water Center: Faculty Publications

Corn seedling emergence is a critical factor affecting crop yields. Accurately predicting emergence is crucial for precise crop growth and development simulation in process-based crop models. While various experimental studies have investigated the relationship between corn seedling emergence and temperature, there remains a scarcity of studies focused on newer corn hybrids. In the present study, statistical models (linear and quadratic functional relationships) are developed based on the seedling emergence of ten current corn hybrids, considering soil and air temperatures as influencing factors. The data used for model development are obtained from controlled soil plant atmospheric research chamber experiments focused on …


Analysis Of Wastewater Samples To Explore Community Substance Use In The United States: Pilot Correlative And Machine Learning Study, Marie A. Severson, Sathaporn Onanong, Alexandra Dolezal, Shannon L. Bartelt-Hunt, Daniel D. Snow, Lisa M. Mcfadden Oct 2023

Analysis Of Wastewater Samples To Explore Community Substance Use In The United States: Pilot Correlative And Machine Learning Study, Marie A. Severson, Sathaporn Onanong, Alexandra Dolezal, Shannon L. Bartelt-Hunt, Daniel D. Snow, Lisa M. Mcfadden

Nebraska Water Center: Faculty Publications

Background: Substance use disorder and associated deaths have increased in the United States, but methods for detecting and monitoring substance use using rapid and unbiased techniques are lacking. Wastewater-based surveillance is a cost-effective method for monitoring community drug use. However, the examination of the results often focuses on descriptive analysis.

Objective: The objective of this study was to explore community substance use in the United States by analyzing wastewater samples. Geographic differences and commonalities of substance use were explored.

Methods: Wastewater was sampled across the United States (n=12). Selected drugs with misuse potential, prescriptions, and over-the-counter drugs …


Characterization Of Environmental Levels Of Pesticide Residues In Household Air And Dust Samples Near A Bioenergy Plant Using Treated Seed As Feedstock, Jabeen Taiba, Eleanor G. Rogan, Daniel D. Snow, Chandran Achutan, Muhammad Zahid Oct 2023

Characterization Of Environmental Levels Of Pesticide Residues In Household Air And Dust Samples Near A Bioenergy Plant Using Treated Seed As Feedstock, Jabeen Taiba, Eleanor G. Rogan, Daniel D. Snow, Chandran Achutan, Muhammad Zahid

Nebraska Water Center: Faculty Publications

Exposure to neonicotinoid insecticides is associated with adverse human health outcomes. There is environmental contamination in Saunders County, Nebraska, due to the accumulation of fungicides and insecticides from a now-closed ethanol plant using seed corn as stock. A pilot study quantified environmental contamination in nearby houses from residual pesticides by measuring dust and air (indoor/outdoor) concentrations of neonicotinoids and fungicides at the study site (households within two miles of the plant) and control towns (20–30 miles away). Air (SASS® 2300 Wetted-Wall Air Sampler) and surface dust (GHOST wipes with 4 × 4-inch template) samples were collected from eleven study …


Leaching Performance Of Nanotechnology-Induced High-Arsenic-Bearing Tooeleite-Like Mineral Nanowaste, Arindam Malakar, Sanjit Das, Samirul Islam, Rajneesh Singh, Sugata Ray Oct 2023

Leaching Performance Of Nanotechnology-Induced High-Arsenic-Bearing Tooeleite-Like Mineral Nanowaste, Arindam Malakar, Sanjit Das, Samirul Islam, Rajneesh Singh, Sugata Ray

Nebraska Water Center: Faculty Publications

For arsenic decontamination from groundwater, arsenic crystallization is becoming adopted due to its sustainability and economic benefits. However, arsenic crystallization technology is a two-step process, which makes it complex and generates hazardous waste. Successful efforts toward making it a single-step process are presented here. The addition of nanorods and ball-milled zinc sulfide nanoparticles to arsenic-contaminated water result in highly monodispersed and higharsenic- containing mineralized nanowaste with a crystalline structure similar to the mineral Tooeleite ((Fe3+6(As3+O3)4SO4(OH)4•4H2O)). This study reports the results of a short-term stability test …


Reaction Steps In Heterogeneous Photocatalytic Oxidation Of Toluene In Gas Phase—A Review, Yerzhigit Tulebekov, Zhandos Orazov, Bagdat Satybaldiyev, Daniel D. Snow, Raphaël Schneider, Bolat Uralbekov Sep 2023

Reaction Steps In Heterogeneous Photocatalytic Oxidation Of Toluene In Gas Phase—A Review, Yerzhigit Tulebekov, Zhandos Orazov, Bagdat Satybaldiyev, Daniel D. Snow, Raphaël Schneider, Bolat Uralbekov

Nebraska Water Center: Faculty Publications

A review of the current literature shows there is no clear consensus regarding the reaction mechanisms of air-borne aromatic compounds such as toluene by photocatalytic oxidation. Potential oxidation reactions over TiO2 or TiO2-based catalysts under ultraviolet and visible (UV/VIS) illumination are most commonly considered for removal of these pollutants. Along the pathways from a model pollutant, toluene, to final mineralization products (CO2 and H2O), the formation of several intermediates via specific reactions include parallel oxidation reactions and formation of less-reactive intermediates on the TiO2 surface. The latter may occupy active adsorption sites and …


Adsorptive–Photocatalytic Performance For Antibiotic And Personal Care Product Using Cu0.5Mn0.5Fe2O4, Chanat Chokejaroenrat, Chainarong Sakulthaew, Athaphon Angkaew, Apiladda Pattanateeradetch, Wuttinun Raksajit, Kanokwan Teingtham, Piyaporn Phansak, Pawee Klongvessa, Daniel D. Snow, Clifford E. Harris, Steven Comfort Jul 2023

Adsorptive–Photocatalytic Performance For Antibiotic And Personal Care Product Using Cu0.5Mn0.5Fe2O4, Chanat Chokejaroenrat, Chainarong Sakulthaew, Athaphon Angkaew, Apiladda Pattanateeradetch, Wuttinun Raksajit, Kanokwan Teingtham, Piyaporn Phansak, Pawee Klongvessa, Daniel D. Snow, Clifford E. Harris, Steven Comfort

Nebraska Water Center: Faculty Publications

The amount of antibiotics and personal care products entering local sewage systems and ultimately natural waters is increasing and raising concerns about long-term human health effects. We developed an adsorptive photocatalyst, Cu0.5Mn0.5Fe2O4 nanoparticles, utilizing co-precipitation and calcination with melamine, and quantified its efficacy in removing paraben and oxytetracycline (OTC). During melamine calcination, Cu0.5Mn0.5Fe2O4 recrystallized, improving material crystallinity and purity for the adsorptive–photocatalytic reaction. Kinetic experiments showed that all four parabens and OTC were removed within 120 and 45 min. We found that contaminant adsorption and reaction …


Incorporation Of Carbon Dioxide Production And Transport Module Into A Soil-Plant-Atmosphere Continuum Model, Sahila Beegum, Wenguang Sun, Dennis Timlin, Zhuangji Wang, David Fleisher, Vangimalla R. Reddy, Chittaranjan Ray Jun 2023

Incorporation Of Carbon Dioxide Production And Transport Module Into A Soil-Plant-Atmosphere Continuum Model, Sahila Beegum, Wenguang Sun, Dennis Timlin, Zhuangji Wang, David Fleisher, Vangimalla R. Reddy, Chittaranjan Ray

Nebraska Water Center: Faculty Publications

Carbon dioxide release from agricultural soils is influenced by multiple factors, including soil (soil properties, soil-microbial respiration, water content, temperature, soil diffusivity), plant (carbon assimilation, rhizosphere respiration), atmosphere (climate, atmospheric carbon dioxide), etc. Accurate estimation of the carbon dioxide (CO2) fluxes in the soil and soil respiration (CO2 flux between soil and atmosphere) requires a process-based modeling approach that accounts for the influence of all these factors. In this study, a module for CO2 production via root and microbial respiration and diffusion-based carbon dioxide transport is developed and integrated with MAIZSIM (a process-based maize crop growth …


Improving The Cotton Simulation Model, Gossym, For Soil, Photosynthesis, And Transpiration Processes, Sahila Beegum, Dennis Timlin, Kambham Raja Reddy, Vangimalla Reddy, Wenguang Sun, Zhuangji Wang, David Fleisher, Chittaranjan Ray May 2023

Improving The Cotton Simulation Model, Gossym, For Soil, Photosynthesis, And Transpiration Processes, Sahila Beegum, Dennis Timlin, Kambham Raja Reddy, Vangimalla Reddy, Wenguang Sun, Zhuangji Wang, David Fleisher, Chittaranjan Ray

Nebraska Water Center: Faculty Publications

GOSSYM, a mechanistic, process-level cotton crop simulation model, has a two-dimensional (2D) gridded soil model called Rhizos that simulates the below-ground processes daily. Water movement is based on gradients of water content and not hydraulic heads. In GOSSYM, photosynthesis is calculated using a daily empirical light response function that requires calibration for response to elevated carbon dioxide ( CO2). This report discusses improvements made to the GOSSYM model for soil, photosynthesis, and transpiration processes. GOSSYM’s predictions of below-ground processes using Rhizos are improved by replacing it with 2DSOIL, a mechanistic 2D finite element soil process model. The photosynthesis …


Occurrence Of Radionuclides And Hazardous Elements In The Transboundary River Basin Kyrgyzstan–Kazakhstan, Mariya A. Severinenko, Vladimir P. Solodukhin, Bekmamat M. Djenbaev, The National Academy Of Science Of The Kyrgyz Republic G. Lennik, Baktiyar T. Zholboldiev, Daniel D. Snow May 2023

Occurrence Of Radionuclides And Hazardous Elements In The Transboundary River Basin Kyrgyzstan–Kazakhstan, Mariya A. Severinenko, Vladimir P. Solodukhin, Bekmamat M. Djenbaev, The National Academy Of Science Of The Kyrgyz Republic G. Lennik, Baktiyar T. Zholboldiev, Daniel D. Snow

Nebraska Water Center: Faculty Publications

Important for irrigation, the transboundary river basin between Kyrgyzstan and Kazakhstan is vulnerable to geochemical and anthropogenic sources of pollution. The use of water use indices, together with measurements of the elemental and radionuclide composition of the water and bottom sediments, provides a means for evaluating the continued use of the water from this region. Recent monitoring shows the highest concentrations of hazardous contaminants include lead and thorium contained in the bottom and banks of the Kichi-Kemin River. These contaminants are likely remnants of an accidental spill at the Aktyuz tailing dump in 1964. The specific activity of the Th-232 …


Projected Long-Term Climate Trends Reveal The Critical Role Of Vapor Pressure Deficit For Soybean Yields In The Us Midwest, Wenguang Sun, David Fleisher, Dennis Timlin, Chittaranjan Ray, Zhuangji Wang, Sahila Beegum, Vangimalla Reddy Mar 2023

Projected Long-Term Climate Trends Reveal The Critical Role Of Vapor Pressure Deficit For Soybean Yields In The Us Midwest, Wenguang Sun, David Fleisher, Dennis Timlin, Chittaranjan Ray, Zhuangji Wang, Sahila Beegum, Vangimalla Reddy

Nebraska Water Center: Faculty Publications

Extreme climate events including heat waves and droughts are projected to become more frequent under future climate change conditions. However, the mechanisms between soybean yields and climate factors, specifically involving variable rainfall and high heat episodes, are still unclear, particularly with respect to spatial trends in the United States (US) Midwest. A recently modified version of the model GLYCIM was used to evaluate rainfed soybean production across 12 states at a 10 km spatial resolution for three time periods (2011–2020, 2051–2060, 2091–2099) under Representative Concentration Pathway (RCP) scenarios 4.5 and 8.5. Results showed that except for the northernmost Midwest counties, …


Importance Of Snowmelt On Soil Nitrate Leaching To Groundwater – A Model Study, Sahila Beegum, Arindam Malakar, Chittaranjan Ray, Daniel D. Snow Feb 2023

Importance Of Snowmelt On Soil Nitrate Leaching To Groundwater – A Model Study, Sahila Beegum, Arindam Malakar, Chittaranjan Ray, Daniel D. Snow

Nebraska Water Center: Faculty Publications

The movement of nitrate to surface water bodies during snow accumulation and melting has been extensively studied, but there are only limited studies on the influence of snow processes on nitrate leaching to groundwater. The present study investigated the impact of snow processes on nitrate leaching to groundwater based on a simulation modeling approach using HYDRUS-1D. HYDRUS-1D model has a temperature threshold-based snow model in addition to water, solute, and heat simulation components. The snow component in HYDRUS-1D was previously not applied to snow simulation studies since the method does not consider a detailed physical and process-based representation of snow …


Time Domain Reflectometry Waveform Interpretation With Convolutional Neural Networks, Zhuangji Wang, Shan Hua, Dennis Timlin, Yuki Kojima, Songtao Lu, Wenguang Sun, David Fleisher, Robert Horton, Vangimalla R. Reddy, Katherine Tully Jan 2023

Time Domain Reflectometry Waveform Interpretation With Convolutional Neural Networks, Zhuangji Wang, Shan Hua, Dennis Timlin, Yuki Kojima, Songtao Lu, Wenguang Sun, David Fleisher, Robert Horton, Vangimalla R. Reddy, Katherine Tully

Nebraska Water Center: Faculty Publications

Interpreting time domain reflectometry (TDR) waveforms obtained in soils with non-uniform water content is an open question. We design a new TDR waveform interpretation model based on convolutional neural networks (CNNs) that can reveal the spatial variations of soil relative permittivity and water content along a TDR sensor. The proposed model, namely TDR-CNN, is constructed with three modules. First, the geometrical features of the TDR waveforms are extracted with a simplified version of VGG16 network. Second, the reflection positions in a TDR waveform are traced using a 1D version of the region proposal network. Finally, the soil relative permittivity values …


Population Health Metrics During The Early Stages Of The Covid-19 Pandemic: Correlative Pilot Study, Marie A. Severson, David A. Cassada, Victor C. Huber, Daniel D. Snow, Lisa M. Mcfadden Oct 2022

Population Health Metrics During The Early Stages Of The Covid-19 Pandemic: Correlative Pilot Study, Marie A. Severson, David A. Cassada, Victor C. Huber, Daniel D. Snow, Lisa M. Mcfadden

Nebraska Water Center: Faculty Publications

Background: COVID-19 has caused nearly 1 million deaths in the United States, not to mention job losses, business and school closures, stay-at-home orders, and mask mandates. Many people have suffered increased anxiety and depression since the pandemic began. Not only have mental health symptoms become more prevalent, but alcohol consumption has also increased during this time. Helplines offer important insight into both physical and mental wellness of a population by offering immediate, anonymous, cheap, and accessible resources for health and substance use disorders (SUD) that was unobstructed by many of the mandates of the pandemic. Further, the pandemic also …


Enrofloxacin And Sulfamethoxazole Sorption On Carbonized Leonardite: Kinetics, Isotherms, Influential Effects, And Antibacterial Activity Toward S. Aureus Atcc 25923, Chanat Chokejaroenrat, Chainarong Sakulthaew, Khomson Satchasataporn, Daniel D. Snow, Tarik E. Ali, Mohammed A. Assiri, Apichon Watcharenwong, Saksit Imman, Nopparat Suriyachai, Torpong Kreetachat Sep 2022

Enrofloxacin And Sulfamethoxazole Sorption On Carbonized Leonardite: Kinetics, Isotherms, Influential Effects, And Antibacterial Activity Toward S. Aureus Atcc 25923, Chanat Chokejaroenrat, Chainarong Sakulthaew, Khomson Satchasataporn, Daniel D. Snow, Tarik E. Ali, Mohammed A. Assiri, Apichon Watcharenwong, Saksit Imman, Nopparat Suriyachai, Torpong Kreetachat

Nebraska Water Center: Faculty Publications

Excessive antibiotic use in veterinary applications has resulted in water contamination and potentially poses a serious threat to aquatic environments and human health. The objective of the current study was to quantify carbonized leonardite (cLND) adsorption capabilities to remove sulfamethoxazole (SMX)- and enrofloxacin (ENR)-contaminated water and to determine the microbial activity of ENR residuals on cLND following adsorption. The cLND samples prepared at 450oC and 850oC (cLND450 and cLND550, respectively) were evaluated for structural and physical characteristics and adsorption capabilities based on adsorption kinetics and isotherm studies. The low pyrolysis temperature of cLND resulted in a …


Tracing Geochemical Sources And Health Risk Assessment Of Uranium In Groundwater Of Arid Zone Of India, P. Pandit, Atul Saini, Sabarathinam Chidambaram, Vinod Kumar, Banjarani Panda, A. L. Ramanathan, Netrananda Sahu, A. K. Singh, Rohit Mehra Jun 2022

Tracing Geochemical Sources And Health Risk Assessment Of Uranium In Groundwater Of Arid Zone Of India, P. Pandit, Atul Saini, Sabarathinam Chidambaram, Vinod Kumar, Banjarani Panda, A. L. Ramanathan, Netrananda Sahu, A. K. Singh, Rohit Mehra

Nebraska Water Center: Faculty Publications

Water quality degradation and metal contamination in groundwater are serious concerns in an arid region with scanty water resources. This study aimed at evaluating the source of uranium (U) and potential health risk assessment in groundwater of the arid region of western Rajasthan and northern Gujarat. The probable source of vanadium (V) and fluorine (F) was also identified. U and trace metal concentration, along with physicochemical characteristics were determined for 265 groundwater samples collected from groundwater of duricrusts and palaeochannels of western Rajasthan and northern Gujarat. The U concentration ranged between 0.6 and 260 μg L−1 with a mean …


Modeling Vapor Transfer In Soil Water And Heat Simulations: A Modularized, Partially-Coupled Approach, Zhuangji Wang, Dennis Timlin, David Fleisher, Wenguang Sun, Sahila Beegum, Sanai Li, Ya Chen, Vandimalla R. Reddy, Katherine Tully, Robert Horton Jan 2022

Modeling Vapor Transfer In Soil Water And Heat Simulations: A Modularized, Partially-Coupled Approach, Zhuangji Wang, Dennis Timlin, David Fleisher, Wenguang Sun, Sahila Beegum, Sanai Li, Ya Chen, Vandimalla R. Reddy, Katherine Tully, Robert Horton

Nebraska Water Center: Faculty Publications

Coupled water and heat transfer models are widely used to analyze soil water content and temperature dynamics, evaluate agricultural management systems, and support crop growth modelling. In relatively dry soils, vapor transfer, rather than liquid water flux, becomes the main pathway for water redistribution. However, in some modularized soil simulators, e.g., 2DSOIL (Timlin et al., 1996), vapor transfer is not included, which may induce errors in soil water and heat modelling. Directly embedding vapor transfer into existing water and heat transfer modules may violate the modularized architecture of those simulators. Therefore, the objectives of this study are to design a …


Ferrihydrite Enrichment In The Rhizosphere Of Unsaturated Soil Improves Nutrient Retention While Limiting Arsenic And Uranium Plant Uptake, Arindam Malakar, Daniel D. Snow, Michael Kaiser, Jordan Shields, Bijesh Maharjan, Harkamal Walia, Daran Rudnick, Chittaranjan Ray Jan 2022

Ferrihydrite Enrichment In The Rhizosphere Of Unsaturated Soil Improves Nutrient Retention While Limiting Arsenic And Uranium Plant Uptake, Arindam Malakar, Daniel D. Snow, Michael Kaiser, Jordan Shields, Bijesh Maharjan, Harkamal Walia, Daran Rudnick, Chittaranjan Ray

Nebraska Water Center: Faculty Publications

Improvement of nutrient use efficiency and limiting trace elements such as arsenic and uranium bioavailability is critical for sustainable agriculture and food safety. Arsenic and uranium possess different properties and mobility in soils, which complicates the effort to reduce their uptake by plants. Here, we postulate that unsaturated soil amended with ferrihydrite nanominerals leads to improved nutrient retention and helps reduce uptake of these geogenic contaminants. Unsaturated soil is primarily oxic and can provide a stable environment for ferrihydrite nanominerals. To demonstrate the utility of ferrihydrite soil amendment, maize was grown in an unsaturated agricultural soil that is known to …


Source Apportionment And Health Risk Assessment Of Nitrate In Foothill Aquifers Of Western Ghats, South India, Banajarani Panda, S. Chidambaram, Daniel D. Snow, Arindam Malakar, Dhiraj Kr Singh, L. Ramanathan Dec 2021

Source Apportionment And Health Risk Assessment Of Nitrate In Foothill Aquifers Of Western Ghats, South India, Banajarani Panda, S. Chidambaram, Daniel D. Snow, Arindam Malakar, Dhiraj Kr Singh, L. Ramanathan

Nebraska Water Center: Faculty Publications

The present research reports the level of nitrate (NO3-), associated health risks and possible sources of contamination in groundwater from south India. Many samples (32%) are above or approaching the recommended level of NO3- for safe drinking water. The correlation analysis indicates different sources of NO3- contamination in different regions rather than a common origin. The isotopic measurements provide information about potential nitrogen sources contributing NO3- to the groundwater. Based on isotope analysis, the sources of NO3- in the groundwater of this region are likely to be from (a) …


Biotransformation Of Doxycycline By Brevundimonas Naejangsanensis And Sphingobacterium Mizutaii Strains, Ting He, Jianguo Bao, Yifei Leng, Daniel D. Snow, Shuqiong Kong, Tong Wang, Xu Li Jun 2021

Biotransformation Of Doxycycline By Brevundimonas Naejangsanensis And Sphingobacterium Mizutaii Strains, Ting He, Jianguo Bao, Yifei Leng, Daniel D. Snow, Shuqiong Kong, Tong Wang, Xu Li

Nebraska Water Center: Faculty Publications

The fate of doxycycline (DC), a second generation tetracycline antibiotic, in the environment has drawn increasing attention in recent years due to its wide usage. Little is known about the biodegradability of DC in the environment. The objective of this study was to characterize the biotransformation of DC by pure bacterial strains with respect to reaction kinetics under different environmental conditions and biotransformation products. Two bacterial strains, Brevundimonas naejangsanensis DD1 and Sphingobacterium mizutaii DD2, were isolated from chicken litter and characterized for their biotransformation capability of DC. Results show both strains rely on cometabolism to biotransform DC with tryptone as …


Removal Of Carbamazepine Onto Modified Zeolitic Tuff In Different Water Matrices: Batch And Continuous Flow Experiments, Othman A. Al-Mashaqbeh, Diya A. Alsafadi, Layal Z. Alsalhi, Shannon L. Bartelt-Hunt, Daniel D. Snow Apr 2021

Removal Of Carbamazepine Onto Modified Zeolitic Tuff In Different Water Matrices: Batch And Continuous Flow Experiments, Othman A. Al-Mashaqbeh, Diya A. Alsafadi, Layal Z. Alsalhi, Shannon L. Bartelt-Hunt, Daniel D. Snow

Nebraska Water Center: Faculty Publications

Carbamazepine (CBZ) is the most frequently detected pharmaceutical residues in aquatic environments effluent by wastewater treatment plants. Batch and column experiments were conducted to evaluate the removal of CBZ from ultra-pure water and wastewater treatment plant (WWTP) effluent using raw zeolitic tuff (RZT) and surfactant modified zeolite (SMZ). Point zero net charge (pHpzc), X-ray diffraction (XRD), X-ray fluorescence (XRF), and Fourier Transform Infrared (FTIR) were investigated for adsorbents to evaluate the physiochemical changes resulted from the modification process using Hexadecyltrimethylammonium bromide (HDTMA-Br). XRD and FTIR showed that the surfactant modification of RZT has created an amorphous surface with new alkyl …


Pesticide Occurrence And Persistence Entering Recreational Lakes In Watersheds Of Varying Land Uses, Jessica Satiroff, Tiffany Messer, Aaron R. Mittelstet, Daniel D. Snow Jan 2021

Pesticide Occurrence And Persistence Entering Recreational Lakes In Watersheds Of Varying Land Uses, Jessica Satiroff, Tiffany Messer, Aaron R. Mittelstet, Daniel D. Snow

Nebraska Water Center: Faculty Publications

Currently little is known of newer pesticide classes and their occurrence and persistence in recreational lakes. Therefore, the objectives of this study were to (1) assess average pesticide concentrations and loadings entering recreational lakes in three mixed land use watersheds throughout the growing season, (2) evaluate pesticide persistence longitudinally within the lakes, and (3) perform an ecotoxicity assessment. Six sampling campaigns were conducted at three lakes from April through October 2018 to measure the occurrence and persistence during pre, middle, and post growing season. Polar organic chemical integrative samplers (POCIS) were placed in streams near lake inlets and monthly samples …


Occurrence Of Arsenite In Surface And Groundwater Associated With A Perennial Stream Located In Western Nebraska, Usa, Arindam Malakar, Rajesh Singh, Jeffrey Westrop, Karrie A. Weber, Christopher N. Elofson, Manish Kumar, Daniel D. Snow Jan 2021

Occurrence Of Arsenite In Surface And Groundwater Associated With A Perennial Stream Located In Western Nebraska, Usa, Arindam Malakar, Rajesh Singh, Jeffrey Westrop, Karrie A. Weber, Christopher N. Elofson, Manish Kumar, Daniel D. Snow

Nebraska Water Center: Faculty Publications

Dissolved arsenic typically results from chemical weathering of arsenic rich sediments and is most often found in oxidized forms in surface water. The mobility of arsenic is controlled by its valence state and also by its association with iron oxides minerals, the forms of which are both influenced by abiotic and biotic processes in aqueous environment. In this study, speciation methods were used to measure and confirm the presence of reduced arsenic species in the surface water of Frenchman creek, a gaining stream that crosses the Colorado- Nebraska border. Selective extraction analysis of aquifer and stream bed sediments shows that …


A Detailed Assessment Of Groundwater Quality In The Kabul Basin, Afghanistan, And Suitability For Future Development, Hussain Ali Jawadi, Jay Sagin, Daniel D. Snow Oct 2020

A Detailed Assessment Of Groundwater Quality In The Kabul Basin, Afghanistan, And Suitability For Future Development, Hussain Ali Jawadi, Jay Sagin, Daniel D. Snow

Nebraska Water Center: Faculty Publications

Abstract: Kabul is one of the most populated cities in Afghanistan and providing resources to support this population in an arid climate presents a serious environmental challenge. The current study evaluated the quality of local Kabul Basin groundwater to determine its suitability water for drinking and irrigation purposes now and into the future. This aim was aided through groundwater parameter assessment as well as determination ofWater Quality Index (WQI) developed from 15 observation points near the city. The results of our physicochemical analysis illustrate that groundwater in the majority of areas of the Kabul Basin is not generally suitable for …


A Detailed Assessment Of Groundwater Quality In The Kabul Basin, Afghanistan, And Suitability For Future Development, Hussain Ali Jawadi, Jay Sagin, Daniel D. Snow Oct 2020

A Detailed Assessment Of Groundwater Quality In The Kabul Basin, Afghanistan, And Suitability For Future Development, Hussain Ali Jawadi, Jay Sagin, Daniel D. Snow

Nebraska Water Center: Faculty Publications

Kabul is one of the most populated cities in Afghanistan and providing resources to support this population in an arid climate presents a serious environmental challenge. The current study evaluated the quality of local Kabul Basin groundwater to determine its suitability water for drinking and irrigation purposes now and into the future. This aim was aided through groundwater parameter assessment as well as determination ofWater Quality Index (WQI) developed from 15 observation points near the city. The results of our physicochemical analysis illustrate that groundwater in the majority of areas of the Kabul Basin is not generally suitable for human …


Development And Performance Assessment Of An Integrated Vermifiltration Based Treatment System For The Treatment Of Feedlot Runoff, Rajneesh Singh, Matteo D'Alessio, Yulie Meneses, Shannon L. Bartelt-Hunt, Brian Woodbury, Chittaranjan Ray Aug 2020

Development And Performance Assessment Of An Integrated Vermifiltration Based Treatment System For The Treatment Of Feedlot Runoff, Rajneesh Singh, Matteo D'Alessio, Yulie Meneses, Shannon L. Bartelt-Hunt, Brian Woodbury, Chittaranjan Ray

Nebraska Water Center: Faculty Publications

The objective of this study was to treat feedlot runoff by developing an ecologically sustainable, affordable, and resilient treatment system having a relatively long life span. Three horizontal flow soil biofilters were utilized in this study: 1) without earthworms and plants (Biofilter (BF)), 2) with earthworms only (Vermifilter (VF)), and 3) with earthworms and plants (Macrophyte Assisted Vermifilter (MAVF)). The experiments were conducted with a hydraulic retention time of four days using Lumbricus terestrris earthworms and Carex frankii wetland plants. The average COD removal from the BF, VF, and MAVF were 23.2–30.4%, 61.4–69.1%, and 68.3–78.1%, respectively. Average TN removal efficiencies …


Legacy And Current Pesticide Residues In Syr Darya, Kazakhstan: Contamination Status, Seasonal Variation And Preliminary Ecological Risk Assessment, Daniel D. Snow, P. Chakraborty, B. Uralbekov, B. Satybaldiev, J. Brett Sallach, L. M. Thornton Hampton, M. Jeffries, A. S. Kolok, Shannon L. Bartelt-Hunt Jul 2020

Legacy And Current Pesticide Residues In Syr Darya, Kazakhstan: Contamination Status, Seasonal Variation And Preliminary Ecological Risk Assessment, Daniel D. Snow, P. Chakraborty, B. Uralbekov, B. Satybaldiev, J. Brett Sallach, L. M. Thornton Hampton, M. Jeffries, A. S. Kolok, Shannon L. Bartelt-Hunt

Nebraska Water Center: Faculty Publications

The Syr Darya is one of two major rivers in Central Asia supplying critical fresh water to the Aral Sea. In spite of the river’s importance and agriculturally-intensive history, few studies have provided a modern evaluation of and the occurrence of pesticide residues potential effects to aquatic life. The primary goal of this investigation was to determine seasonal variations in ambient concentrations of modern and legacy pesticides in bottom sediment and water of the Syr Darya in Kazakhstan (KZ) downstream from an agriculturally-intensive watershed in Uzbekistan. Grab samples and passive samplers were used at five remote sampling stations during June …


Climate Change Impacts The Subsurface Transport Of Atrazine And Estrone Originating From Agricultural Production Activities, Renys Enrique Barrios, Simin Akbariyeh, Chuyang Liu, Khalid Muzamil Gani, Margarita T. Kovalchuk, Xu Li, Yusong Li, Daniel D. Snow, Zhenghong Tang, John Gates, Shannon L. Bartelt-Hunt Jun 2020

Climate Change Impacts The Subsurface Transport Of Atrazine And Estrone Originating From Agricultural Production Activities, Renys Enrique Barrios, Simin Akbariyeh, Chuyang Liu, Khalid Muzamil Gani, Margarita T. Kovalchuk, Xu Li, Yusong Li, Daniel D. Snow, Zhenghong Tang, John Gates, Shannon L. Bartelt-Hunt

Nebraska Water Center: Faculty Publications

Climate change will impact soil properties such as soil moisture, organic carbon and temperature and changes in these properties will influence the sorption, biodegradation and leaching of trace organic contaminants to groundwater. In this study, we conducted a modeling case study to evaluate atrazine and estrone transport in the subsurface under current and future climate conditions at a field site in central Nebraska. According to the modeling results, in the future, enhanced evapotranspiration and increased average air temperature may cause drier soil conditions, which consequently reduces the biodegradation of atrazine and estrone in the water phase. On the other hand, …


Swine Slurry Characteristics As Affected By Selected Additives And Disinfectants, Jon Duerschner, Shannon L. Bartelt-Hunt, Kent Eskridge, John E. Gilley, Xu Li, Amy M. Schmidt, Daniel D. Snow Jan 2020

Swine Slurry Characteristics As Affected By Selected Additives And Disinfectants, Jon Duerschner, Shannon L. Bartelt-Hunt, Kent Eskridge, John E. Gilley, Xu Li, Amy M. Schmidt, Daniel D. Snow

Nebraska Water Center: Faculty Publications

Current swine industry practice is to house animals in confinement facilities which capture and store feces and urine as slurry in pits below the production area. Additives and disinfectants may be introduced into the manure pits. This study was conducted to measure the effects of additives and disinfectants on temporal changes in swine slurry characteristics. Slurry from a commercial swine production facility in southeast Nebraska, USA was collected and transferred to 57 L reactors located within a greenhouse. Selected additives and disinfectants were added to the reactors and physical properties, chemical characteristics, and antibiotic concentrations were monitored for 40 days. …


Applied Injected Air Into Subsurface Drip Irrigation: Plant Uptake Of Pharmaceuticals And Soil Microbial Communities, Matteo D'Alessio, Lisa M. Durso, Clinton Williams, Christopher A. Olson, Chittaranjan Ray, Ellen Paparozzi Jan 2020

Applied Injected Air Into Subsurface Drip Irrigation: Plant Uptake Of Pharmaceuticals And Soil Microbial Communities, Matteo D'Alessio, Lisa M. Durso, Clinton Williams, Christopher A. Olson, Chittaranjan Ray, Ellen Paparozzi

Nebraska Water Center: Faculty Publications

The growing global food security crisis is complicated by the need for increased crop production with less arable land and limited water resources. Reuse of treated wastewater for agricultural irrigation is becoming more common, often paired with other conservation measures such as subsurface drip irrigation (SDI). Passively injecting air into SDI systems increases crop yields and overcomes root zone wetting issues. However, when used with treated irrigation water, contaminants in the water might be taken up by the crops. This paper investigates the impact of air-injected water containing caffeine, carbamazepine, and gemfibrozil on plant uptake and soil microbial communities in …


Measuring The Occurrence Of Antibiotics In Surface Water Adjacent To Cattle Grazing Areas Using Passive Samplers, Nasrin Naderi Beni, Daniel D. Snow, Elaine D. Berry, Aaron R. Mittelstet, Tiffany Messer, Shannon L. Bartelt-Hunt Jan 2020

Measuring The Occurrence Of Antibiotics In Surface Water Adjacent To Cattle Grazing Areas Using Passive Samplers, Nasrin Naderi Beni, Daniel D. Snow, Elaine D. Berry, Aaron R. Mittelstet, Tiffany Messer, Shannon L. Bartelt-Hunt

Nebraska Water Center: Faculty Publications

A wide variety of antibiotics and other pharmaceuticals are used in livestock production systems and residues passed to the environment, often unmetabolized, after use and excretion. Antibiotic residuesmay be transported frommanure-treated soils via runoff and are also capable of reaching surface and groundwater systems through a variety of pathways. The occurrence and persistence of antibiotics in the environment is a concern due to the potential for ecological effects and proliferation of environmental antibiotic resistance in pathogenic organisms. In the present study, the occurrence and seasonal variation of 24 commonly-used veterinary antibiotics was evaluated in surface water adjacent to several livestock …