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Water quality

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The Efficacy Of Conservation Practices In Reducing Floods And Improving Water Quality, Shivendra Srivastava, Andrea D. Basche, Elbert Traylor, Tirthankar Roy May 2023

The Efficacy Of Conservation Practices In Reducing Floods And Improving Water Quality, Shivendra Srivastava, Andrea D. Basche, Elbert Traylor, Tirthankar Roy

Department of Civil and Environmental Engineering: Faculty Publications

Conservation practices such as crop rotation, filter strips, and constructed wetlands are nature-based approaches intended to safeguard natural resources in agricultural landscapes. In this study, we reviewed the literature on how conservation practices, both at watershed and field scales, have been proven to subdue flood peaks, surface runoff, soil erosion, sediment transport, and nutrient loss. We classified different conservation practices based on the mode of their application (i.e., in-field, edge-of-field, and structural practices) and described what prior research efforts have concluded about the efficacy of different practices. At the field scale, practices such as reduced or no-till farming, grassed waterways, …


Downstream Hydrochemistry And Irrigation Water Quality Of The Syr Darya, Aral Sea Basin, South Kazakhstan, Bagdat Satybaldiyev, Baimurat Ismailov, Nurbek Nurpeisov, Kairat Kenges, Daniel D. Snow, Arindam Malakar, Omirzhan Taukebayev, Bolat Uralbekov May 2023

Downstream Hydrochemistry And Irrigation Water Quality Of The Syr Darya, Aral Sea Basin, South Kazakhstan, Bagdat Satybaldiyev, Baimurat Ismailov, Nurbek Nurpeisov, Kairat Kenges, Daniel D. Snow, Arindam Malakar, Omirzhan Taukebayev, Bolat Uralbekov

Daugherty Water for Food Global Institute: Faculty Publications

New hydrochemical measurements from the Syr Darya provide insights into factors affecting the composition and quality of a major freshwater source replenishing the Aral Sea. This river is heavily used for power and irrigation and crosses territories of four Central Asia republics. It is intensely managed, draining several major tributaries, many reservoirs, and numerous irrigation distribution systems and canals. Analysis of seasonal changes in dissolved ion concentrations using geochemical diagrams, elemental ratios, statistical correlation, and equilibrium modeling allowed the characterization of mineral formation processes that control the dissolved chemical composition. Measured water hydrochemistry and composition type differs substantially from previous …


The Concentration Of Heavy Metals In Lincoln Nebraska's Tap Water, Evan Neuhaus Mar 2023

The Concentration Of Heavy Metals In Lincoln Nebraska's Tap Water, Evan Neuhaus

Honors Theses

Heavy metals are commonplace in nature, and are typically found in scarce quantities in all drinking sources. However, in high enough concentrations, they can have a myriad of negative health effects. This study seeks to find the concentrations of such metals in the Lincoln water supply utilizing the resources of the Water Center at the University of Nebraska at Lincoln. To test for discrete concentrations of trace elements, a method of using Inductively Coupled Plasma Mass Spectrometry (ICP-MS) was implemented. ICP-MS uses plasma to ionize and atomize a sample which is then filtered into a series of cones into a …


Local-Scale Impacts Of Water Hyacinth On Water Quality In A Hypereutrophic Lake, J. R. Corman, A. Z. Roegner, Z. Ogari, T. R. Miller, C. M. Aura Jan 2023

Local-Scale Impacts Of Water Hyacinth On Water Quality In A Hypereutrophic Lake, J. R. Corman, A. Z. Roegner, Z. Ogari, T. R. Miller, C. M. Aura

School of Natural Resources: Documents and Reviews

No abstract provided.


The North Platte River Valley: The Intersectionality Between Water Quality And People, Anni Poetzl Dec 2022

The North Platte River Valley: The Intersectionality Between Water Quality And People, Anni Poetzl

School of Natural Resources: Dissertations, Theses, and Student Research

The North Platte River (NPR) Valley of western Nebraska is a semi-arid watershed with row crop production, livestock production, and urban land use activity and has a population of diverse stakeholders. These land use activities contribute to the enrichment of surface waters, such as streams, which can affect human and ecosystem health, as well as economic development and recreational activities. The project objectives are to: (1) quantify the movement of dissolved inorganic nutrients from the land within the NPR Valley to the NPR via tributaries and canals, (2) identify spatiotemporal variability of nutrient limitation of periphyton growth within the NPR, …


Water Quality, Carrier Volume And Droplet Size Effects On Herbicide Efficacy And Drift Potential, Barbara Houston Jun 2022

Water Quality, Carrier Volume And Droplet Size Effects On Herbicide Efficacy And Drift Potential, Barbara Houston

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Herbicide performance is directly related to the amount of active ingredient that has been deposited on the plant. Hence, spray solution characteristics and application parameters are crucial in determining the efficacy of an herbicide application. To maximize the effectiveness of chemical control, methods to deliver full chemical dose must be utilized: allowing the active ingredient to be readily absorbed once added to the carrier and mitigating off-target movement and low herbicide doses. Water is the most frequently used carrier in herbicide applications. Chemical parameters, such as water hardness and pH, can have a critical role in herbicide performance. It is …


Influences Of Seasonality And Habitat Quality On Great Lakes Coastal Wetland Fish Community Composition And Diets, Sara N. Diller, Anna M. Harrison, Kurt P. Kowalski, Valerie J. Brady, Jan J. H. Ciborowski, Matthew J. Cooper, Joshua D. Dumke, Joseph P. Gathman, Carl R. Ruetz Iii, Donald G. Uzarski, Douglas A. Wilcox, Jeffrey S. Schaeffer May 2022

Influences Of Seasonality And Habitat Quality On Great Lakes Coastal Wetland Fish Community Composition And Diets, Sara N. Diller, Anna M. Harrison, Kurt P. Kowalski, Valerie J. Brady, Jan J. H. Ciborowski, Matthew J. Cooper, Joshua D. Dumke, Joseph P. Gathman, Carl R. Ruetz Iii, Donald G. Uzarski, Douglas A. Wilcox, Jeffrey S. Schaeffer

United States Geological Survey: Staff Publications

Great Lakes coastal wetlands (GLCW) have been severely degraded by anthropogenic activity over the last several decades despite their critical role in fish production. Many Great Lakes fish species use coastal wetland habitats for spawning, feeding, shelter, and nurseries throughout the year. The goal of our study was to compare GLCW fish community composition in the spring, summer, and fall months and investigate how water quality relates to fish diversity, the presence of functional groups, and juvenile fish diets. We summarized fish data collected from GLCW across the basin and used the coastal wetland monitoring program’s water quality-land use indicator …


Management-Intensive Grazing Impacts On Total Escherichia Coli, E. Coli O157: H7, And Antibiotic Resistance Genes In A Riparian Stream, Laura M. Rubeck, James E. Wells, Kathy Hanford, Lisa M. Durso, Walter H. Schacht, Elaine D. Berry Jan 2022

Management-Intensive Grazing Impacts On Total Escherichia Coli, E. Coli O157: H7, And Antibiotic Resistance Genes In A Riparian Stream, Laura M. Rubeck, James E. Wells, Kathy Hanford, Lisa M. Durso, Walter H. Schacht, Elaine D. Berry

Department of Agronomy and Horticulture: Faculty Publications

The impacts of management-intensive grazing (MIG) of cattle on concentrations of total Escherichia coli, total suspended solids (TSS), and nitrate-nitrite nitrogen (NO3+NO2-N), and occurrence of E. coli O157:H7 and selected antibiotic resistance genes (ARGs) in stream water and/or sediments were evaluated. Cattle were grazed for twoweek periods in May in each of three years. Overall, grazing increased total E. coli in downstream water by 0.89 log10 MPN/100 mL (p < 0.0001), and downstream total E. coli concentrations were higher than upstream over all sampling intervals. Downstream TSS levels also increased (p ≤ 0.0294) during grazing. In contrast, there was …


Wild Pig Removal Reduces Pathogenic Bacteria In Low-Order Streams, Sara A. Bolds, B. Graeme Lockaby, Latif Kalin, Stephen S. Ditchkoff, Mark D. Smith, Kurt Vercauteren Jan 2022

Wild Pig Removal Reduces Pathogenic Bacteria In Low-Order Streams, Sara A. Bolds, B. Graeme Lockaby, Latif Kalin, Stephen S. Ditchkoff, Mark D. Smith, Kurt Vercauteren

USDA Wildlife Services: Staff Publications

Invasive wild pig populations have undergone enormous increases in the United States and particularly across the southern U.S. in recent years. High fecundity rates and abilities to adapt quickly to varied habitats have enabled pig populations to become entrenched and difficult to eliminate. The pigs cause many negative impacts on ecosystems including degradation of water quality through infusion of fecal contamination and other non-point source pollutants. Our goal was to determine the effects of pig removal on water quality in streams that were known to be significantly polluted by pig activity Bolds (J Environ Qual 50: 441–453, 2021). We compared …


Dammed Water Quality—Longitudinal Stream Responses Below Beaver Ponds In The Umpqua River Basin, Oregon, John R. Stevenson, Jason B. Dunham, Steven M. Wondzell, Jimmy Taylor Jan 2022

Dammed Water Quality—Longitudinal Stream Responses Below Beaver Ponds In The Umpqua River Basin, Oregon, John R. Stevenson, Jason B. Dunham, Steven M. Wondzell, Jimmy Taylor

USDA Wildlife Services: Staff Publications

Beaver-related restoration (BRR) has gained popularity as a means of improving stream ecosystems, but the effects are not fully understood. Studies of dissolved oxygen (DO) and water temperature, key water quality metrics for salmonids, have demonstrated improved conditions in some cases, but warming and decreased DO have been more commonly reported in meta-analyses. These results point to the contingencies that can influence outcomes from BRR. We examined water quality related to beaver ponds in a diverse coastal watershed (Umpqua River Basin, OR, USA). We monitored water temperature 0–400m above and below beaver ponds and at pond surfaces and bottoms across …


Modeling Water Quantity And Quality Nonlinearities For Watershed Adaptability To Hydroclimate Extremes In Agricultural Landscapes, Juan Carlos Jaimes-Correa, Francisco Muñoz-Arriola, Shannon Bartelt-Hunt Jan 2022

Modeling Water Quantity And Quality Nonlinearities For Watershed Adaptability To Hydroclimate Extremes In Agricultural Landscapes, Juan Carlos Jaimes-Correa, Francisco Muñoz-Arriola, Shannon Bartelt-Hunt

Department of Biological Systems Engineering: Papers and Publications

Changing water supplies and demands, inherent to climate fluctuations and human activities, are pushing for a paradigm shift in water management worldwide. The occurrence of extreme hydrometeorological and climate events such as extended wet periods and droughts, compounded with contaminants, impair the access to water resources, demanding novel designs, construction, and management across multiple hydrologic scales and biogeochemical processes. A constraint to studying hydrologic and biogeochemical disturbances and improving best management practices for water quantity and quality at the watershed scale resides in the suitable monitoring, data availability, and the creation of frameworks. We hypothesize that streamflow and contaminants, simulated …


A Biological And Chemical Approach To Restoring Water Quality: A Case Study In An Urban Eutrophic Pond, Levi J. Mckercher, Tiffany L. Messer, Aaron R. Mittelstet, Steve D. Comfort Jan 2022

A Biological And Chemical Approach To Restoring Water Quality: A Case Study In An Urban Eutrophic Pond, Levi J. Mckercher, Tiffany L. Messer, Aaron R. Mittelstet, Steve D. Comfort

School of Natural Resources: Faculty Publications

Efforts to improve water quality of eutrophic ponds often involve implementing changes to watershed management practices to reduce external nutrient loads. While this is required for long-term recovery and prevention, eutrophic conditions are often sustained through the recycling of internal nutrients already present within the waterbody. In particular, internal phosphorus bound to organic material and adsorbed to sediment has the potential to delay lake recovery for decades. Thus, pond and watershed management techniques are needed that not only reduce external nutrient loading but also mitigate the effects of internal nutrients already present. Therefore, our objective was to demonstrate a biological …


Differential Survival Of Non-O157 Shiga Toxigenic Escherichia Coli In Simulated Cattle Feedlot Runoff, Lisa M. Durso, John E. Gilley, Daniel N. Miller Jan 2021

Differential Survival Of Non-O157 Shiga Toxigenic Escherichia Coli In Simulated Cattle Feedlot Runoff, Lisa M. Durso, John E. Gilley, Daniel N. Miller

Department of Biological Systems Engineering: Papers and Publications

Environmental survival time is important when evaluating adverse health outcomes from foodborne pathogens. Although outbreaks associated with manure-impacted irrigation or runoff water are relatively infrequent, their broad scope, regulatory importance, and severe health outcomes highlight the need to better understand the environmental survival of manure-borne pathogens. Shiga toxigenic Escherichia coli (STEC) are excreted in feces and persist in the environment until they die or recolonize a new host. Surface waters contaminated with manure-borne STEC can infect humans through drinking and recreational water use or irrigated crops that are minimally cooked. In this study, manure-impacted water microcosms mimicking beef cattle feedlot …


Distribution Of Antibiotic-Resistant Enterobacteriaceae Pathogens In Potable Spring Water Of Eastern Indian Himalayas: Emphasis On Virulence Gene And Antibiotic Resistance Genes In Escherichia Coli, Ashish Kumar Singh, Saurav Das, Santosh Kumar, Varsha Rani Gajamer, Ishfaq Nabi Najar, Yanchen D. Lepcha, Hare Krishna Tiwari, Samer Singh Nov 2020

Distribution Of Antibiotic-Resistant Enterobacteriaceae Pathogens In Potable Spring Water Of Eastern Indian Himalayas: Emphasis On Virulence Gene And Antibiotic Resistance Genes In Escherichia Coli, Ashish Kumar Singh, Saurav Das, Santosh Kumar, Varsha Rani Gajamer, Ishfaq Nabi Najar, Yanchen D. Lepcha, Hare Krishna Tiwari, Samer Singh

Department of Agronomy and Horticulture: Faculty Publications

Every year millions of people die due to fatal waterborne diseases around the world especially in developing countries like India. Sikkim, a northeastern state of India, greatly depends on natural water sources. About 80% of the population of Sikkim depends on natural spring water for domestic as well as agricultural use. Recent waterborne disease outbreaks in the state raises a concerning question on water quality. In this study, we analyzed water quality especially for the detection of Enterobacteriaceae members from four districts of the state. Isolation with selective culture media techniques and taxonomic characterization of Enterobacteriaceae bacteria with 16S rRNA …


Use Of Citizen Science In Monitoring Groundwater Quality: A Case Study From Nebraska, Christopher Olson Aug 2020

Use Of Citizen Science In Monitoring Groundwater Quality: A Case Study From Nebraska, Christopher Olson

School of Natural Resources: Dissertations, Theses, and Student Research

Citizen science has a key role in modernizing effective communication between professional scientists and the general public. However, citizen science differs to that of professional science due to equipment and experience and is a topic argued against citizen science. However, technology in water quality testing has developed in simplicity and affordability to a point where high school students, with hands-on training, can collect groundwater samples and test for quality themselves. Nebraska groundwater quality is a critical part of the state and can utilize high school students as citizen scientists for their communities. High school students from rural communities across Nebraska …


Effects Of Combined Conservation Practices On Soil And Water Quality In The Central Mississippi River Basin, C. Baffaut, F. Ghidey, R. N. Lerch, K. S. Veum, E. J. Sadler, K. A. Sudduth, N. R. Kitchen Jun 2020

Effects Of Combined Conservation Practices On Soil And Water Quality In The Central Mississippi River Basin, C. Baffaut, F. Ghidey, R. N. Lerch, K. S. Veum, E. J. Sadler, K. A. Sudduth, N. R. Kitchen

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Conventional cultivation of claypan soils leads to soil and water quality degradation because of high runoff and associated soil erosion. The Goodwater Creek Experimental Watershed, which is part of the USDA Agricultural Research Service Benchmark Conservation Effects Assessment Project, Watershed Assessment Studies, was established to address these issues. Plot studies have highlighted trade-offs between erosion control and herbicide or nutrient runoff. There is a need for long-term field-scale evaluation of combined practices that reduce sediment, nutrient, and herbicide losses by runoff. A 36 ha field located in Missouri was under a conventional corn (Zea mays L.)-soybean (Glycine max L.) system …


Risk And Cost Assessment Of Nitrate Contamination In Domestic Wells, Pongpun Juntakut, Erin M.K. Haacker, Daniel D. Snow, Chittaranjan Ray Feb 2020

Risk And Cost Assessment Of Nitrate Contamination In Domestic Wells, Pongpun Juntakut, Erin M.K. Haacker, Daniel D. Snow, Chittaranjan Ray

Daugherty Water for Food Global Institute: Faculty Publications

This study combines empirical predictive and economics models to estimate the cost of remediation for domestic wells exceeding suggested treatment thresholds for nitrates. A multiple logistic regression model predicted the probability of well contamination by nitrate, and a life cycle costing methodology was used to estimate costs of nitrate contamination in groundwater in two areas of Nebraska. In south-central Nebraska, 37% of wells were estimated to be at risk of exceeding a threshold of 7.5 mg/L as N, and 17% were at risk of exceeding 10 mg/L as N, the legal limit for human consumption in the United States. In …


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. …


Reactive Oxygen Species (Ros) Mediated Degradation Of Organophosphate T Pesticides By The Green Microalgae Coccomyxa Subellipsoidea☆, Timothy J Nicodemus, Concetta C. Dirusso, Mark A. Wilson, Paul N. Black Jan 2020

Reactive Oxygen Species (Ros) Mediated Degradation Of Organophosphate T Pesticides By The Green Microalgae Coccomyxa Subellipsoidea☆, Timothy J Nicodemus, Concetta C. Dirusso, Mark A. Wilson, Paul N. Black

Department of Biochemistry: Faculty Publications

The aim of this study was to define the mechanism allowing the green alga Coccomyxa subellipsoidea to break down organophosphates from agricultural run-off. This study found that metabolically active cultures of the microalga C. subellipsoidea breakdown organophosphates (paraoxon, malathion and diazinon) with differing structural conformations in freshwater through a mechanism that requires the formation of reactive oxygen species (ROS) with little to no toxic effects on the algae. Under these conditions, organophosphate levels were reduced to 0.1 mg/mL or less over the 8–10 day experimental period. These findings demonstrate a biological- based system can be tailored for the remediation of …


Accumulation And Release Of Nutrients By Immersed Stalks Collected On Selected Dates Following Harvest, John E. Gilley, David B. Marx Jan 2020

Accumulation And Release Of Nutrients By Immersed Stalks Collected On Selected Dates Following Harvest, John E. Gilley, David B. Marx

Department of Biological Systems Engineering: Papers and Publications

The concentrations of phosphorus (P) and nitrogen (N) in runoff from cropland areas may be influenced by accumulation and release of P and N by stalk residues. A laboratory study was conducted to measure the effects of time since harvest and immersion period on accumulation and release of P and N by corn, soybean, and wheat stalks. Experimental variables included type of stalk material (corn, soybean, and wheat), time since harvest (six residue collection dates over an approximate 1-year period), and stalk immersion period (25 s (0.42 min), 250 s (4.2 min), 2500 s (42 min), 25,000 s (6.9 h), …


Risk And Cost Assessment Of Nitrate Contamination In Domestic Wells, Pongpun Juntakut, Erin M.K. Haacker, Daniel D. Snow, Chittaranjan Ray Jan 2020

Risk And Cost Assessment Of Nitrate Contamination In Domestic Wells, Pongpun Juntakut, Erin M.K. Haacker, Daniel D. Snow, Chittaranjan Ray

Department of Civil and Environmental Engineering: Faculty Publications

This study combines empirical predictive and economics models to estimate the cost of remediation for domestic wells exceeding suggested treatment thresholds for nitrates. A multiple logistic regression model predicted the probability of well contamination by nitrate, and a life cycle costing methodology was used to estimate costs of nitrate contamination in groundwater in two areas of Nebraska. In south-central Nebraska, 37% of wells were estimated to be at risk of exceeding a threshold of 7.5 mg/L as N, and 17% were at risk of exceeding 10 mg/L as N, the legal limit for human consumption in the United States. In …


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

Department of Biological Systems Engineering: Papers and 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. …


Influence Of Setback Distance On Antibiotics And Antibiotic Resistance Genes In Runoff And Soil Following The Land Application Of Swine Manure Slurry, Maria C. Hall, Noelle Mware, John E. Gilley, Shannon L. Bartelt-Hunt, Daniel D. Snow, Amy M. Schmidt Schmidt, Kent M. Eskridge, Xu Li Jan 2020

Influence Of Setback Distance On Antibiotics And Antibiotic Resistance Genes In Runoff And Soil Following The Land Application Of Swine Manure Slurry, Maria C. Hall, Noelle Mware, John E. Gilley, Shannon L. Bartelt-Hunt, Daniel D. Snow, Amy M. Schmidt Schmidt, Kent M. Eskridge, Xu Li

Department of Biological Systems Engineering: Papers and Publications

The environmental spread of antibiotics and antibiotic resistance genes (ARGs) from the land application of livestock wastes can be a potential public health threat. The objective of this study was to assess the effects of setback distance, which determines how close manure may be applied in relation to surface water, on the transport of antibiotics and ARGs in runoff and soil following land application of swine manure slurry. Rainfall simulation tests were conducted on field plots covered with wheat residues, each of which contained an upslope manure region where slurry was applied and an adjacent downslope setback region that did …


Exposure And Potential Effects Of Pesticides And Pharmaceuticals In Protected Streams Of The Us National Park Service Southeast Region, Paul M. Bradley, Kristin M. Romanok, Jeffrey R. Duncan, William A. Battaglin, Jimmy M. Clark, Michelle L. Hladik, Bradley J. Huffman, Luke R. Iwanowicz, Celeste A. Journey, Kelly L. Smalling Nov 2019

Exposure And Potential Effects Of Pesticides And Pharmaceuticals In Protected Streams Of The Us National Park Service Southeast Region, Paul M. Bradley, Kristin M. Romanok, Jeffrey R. Duncan, William A. Battaglin, Jimmy M. Clark, Michelle L. Hladik, Bradley J. Huffman, Luke R. Iwanowicz, Celeste A. Journey, Kelly L. Smalling

United States National Park Service: Publications

Globally, protected areas offer refugia for a broad range of taxa including threatened and endangered species. In the United States (US), the National Park Service (NPS) manages public lands to preserve biodiversity, but increasing park visitation and development of surrounding landscapes increase exposure to and effects from bioactive contaminants. The risk (exposure and hazard) to NPS protected-stream ecosystems within the highly urbanized southeast region (SER) from bioactive contaminants was assessed in five systems based on 334 pesticide and pharmaceutical analytes in water and 119 pesticides in sediment. Contaminant mixtures were common across all sampled systems, with approximately 24% of the …


Effects Of Dietary Protein Content On Hybrid Tilapia (Oreochromis Aureus × O. Niloticus) Performance, Common Microbial Off-Flavor Compounds, And Water Quality Dynamics In An Outdoor Biofloc Technology Production System, Bartholomew W. Green, Steven D. Rawles, Kevin K. Schrader, T. Gibson Gaylord, Matthew E. Mcentire Jan 2019

Effects Of Dietary Protein Content On Hybrid Tilapia (Oreochromis Aureus × O. Niloticus) Performance, Common Microbial Off-Flavor Compounds, And Water Quality Dynamics In An Outdoor Biofloc Technology Production System, Bartholomew W. Green, Steven D. Rawles, Kevin K. Schrader, T. Gibson Gaylord, Matthew E. Mcentire

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Given tilapia grown in the biofloc technology production system can consume the biofloc, it should be possible to optimize formulated diet protein content to account for nutrition derived from consuming biofloc. The present study, conducted in an outdoor biofloc technology production system, evaluated impacts on fish production indices, common microbial off-flavors, and water quality dynamics for hybrid tilapia (Oreochromis aureus×O. niloticus) fed diets formulated to contain 22.5%, 27.7%, and 32.3% digestible protein (DP) and 6% lipid. Fingerlings (32.2 ± 10.1 g/fish) were stocked in tanks (18.6m2; 16.6m3) in May 2016 at 25/m2 (29/m3) and grown for 5 months to market …


Seasonality Of Nitrogen Balances In A Mediterranean Climate Watershed, Oregon, Us, Jiajia Lin, Jana E. Compton, Scott G. Leibowitz, George Mueller-Warrant, William Matthews, Stephen H. Schoenholtz, Daniel M. Evans, Rob A. Coulombe Dec 2018

Seasonality Of Nitrogen Balances In A Mediterranean Climate Watershed, Oregon, Us, Jiajia Lin, Jana E. Compton, Scott G. Leibowitz, George Mueller-Warrant, William Matthews, Stephen H. Schoenholtz, Daniel M. Evans, Rob A. Coulombe

United States Environmental Protection Agency: Staff Publications

We constructed a seasonal nitrogen (N) budget for the year 2008 in the Calapooia River Watershed (CRW), an agriculturally dominated tributary of the Willamette River (Oregon, U.S.) under Mediterranean climate. Synthetic fertilizer application to agricultural land (dominated by grass seed crops) was the source of 90% of total N input to the CRW. Over 70% of the stream N export occurred during the wet winter, the primary time of fertilization and precipitation, and the lowest export occurred in the dry summer. Averaging across all 58 tributary subwatersheds, 19% of annual N inputs were exported by streams, and 41% by crop …


Factors Influencing Farmers Adoption Of Best Management Practices: A Review And Synthesis, Tingting Liu, Randall J.F. Bruins, Matthew T. Heberling Jan 2018

Factors Influencing Farmers Adoption Of Best Management Practices: A Review And Synthesis, Tingting Liu, Randall J.F. Bruins, Matthew T. Heberling

School of Natural Resources: Faculty Publications

No abstract provided.


Lignocellulosic-Based Bioenergy And Water Quality Parameters: A Review, Bharat Sharma Acharya, Humberto Blanco-Canqui Jan 2018

Lignocellulosic-Based Bioenergy And Water Quality Parameters: A Review, Bharat Sharma Acharya, Humberto Blanco-Canqui

Department of Agronomy and Horticulture: Faculty Publications

High rates of crop residue removal as biofuel feedstocks could increase losses of nonpoint source pollutants, negatively affecting water quality. An alternative to residue removal can be growing dedicated bioenergy crops such as warm season grasses (WSGs) and short-rotation woody crops (SRWCs). Yet, our understanding of the implications of growing dedicated bioenergy crops on water quality is limited. Thus, we (i) synthesized and compared the impacts of crop residue removal, WSGs, and SRWCs on water quality parameters (i.e., sediment and nutrient runoff, and nutrient leaching) and (ii) identified research gaps for growing dedicated energy crops. Literature indicates that residue removal …


Setback Distance Requirements For Removal Of Swine Slurry Constituents In Runoff, John E. Gilley, Shannon L. Bartelt-Hunt, Kent M. Eskridge, Xu Li, Amy M. Schmidt, Daniel D. Snow Dec 2017

Setback Distance Requirements For Removal Of Swine Slurry Constituents In Runoff, John E. Gilley, Shannon L. Bartelt-Hunt, Kent M. Eskridge, Xu Li, Amy M. Schmidt, Daniel D. Snow

Department of Biological Systems Engineering: Papers and Publications

The use of setback distances for manure application on cropland areas adjacent to surface water bodies could serve a function similar to vegetative filter strips. However, little information currently exists to identify the setback distances necessary to effectively reduce the transport of contaminants in runoff. The objective of this study was to determine the effects of setback distance and runoff rate on concentrations of selected constituents in runoff following land application of swine slurry to a no-till cropland area in southeast Nebraska. The study site had a residue cover of 7.73 Mg ha-1 and a slope gradient of 4.9%. The …


Comparative Water Quality And Channel Catfish Production In Earthen Ponds And A Biofloc Technology Production System, Bartholomew W. Green, Matthew E. Mcentire Jan 2017

Comparative Water Quality And Channel Catfish Production In Earthen Ponds And A Biofloc Technology Production System, Bartholomew W. Green, Matthew E. Mcentire

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

This 210-day study compared variation in water quality and fish growth for channel catfish (Ictalurus punctatus; 47 g/fish) stocked in earthen ponds (1.5 fish/m2, 14,820/ha) and in a biofloc technology (BFT) production system with high-density polyethylene-lined rectangular tanks (12.6 fish/m2, 126,000/ha). Feed input and culture environment affected water-quality dynamics. In ponds, phytoplankton uptake predominated and little nitrification occurred, whereas in the BFT system phytoplankton uptake and nitrification maintained low ammonia-nitrogen concentrations. Size classes of fish were skewed toward the larger market sizes in ponds and toward smaller market sizes in the BFT system. Mean …