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Full-Text Articles in Other Civil and Environmental Engineering

Efficiency Of Bank Filtration In The Removal Of Cyanotoxins Under Different Levels Of Nutrients, Luke Walkenhorst Jul 2022

Efficiency Of Bank Filtration In The Removal Of Cyanotoxins Under Different Levels Of Nutrients, Luke Walkenhorst

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

Harmful Algal Blooms (HABs) are an increasing concern not only in Nebraska, but across the world. Increasing global temperatures in conjunction with overuse of synthetic fertilizers are leading causes to the increasing frequency and concern of HABs. In the present work, the effectiveness of simulated bank filtration (BF), as an economical water treatment option, to remove cyanotoxins under different levels of nutrients (nitrates and phosphates) was investigated. Vertical flow-through columns pre-acclimated with two levels of nutrients (e.g., nitrate and phosphate—10 vs. 50 mg/L) were exposed to two different levels of cyanotoxins (10 vs. 75 μg/L). Results from the study confirmed …


Agrochemical Indicators Of New Irrigated Graph-Meadow Soils Formed On The Iii Underfladder Terrace Of Syrdarya, J.M. Kuziev Dec 2020

Agrochemical Indicators Of New Irrigated Graph-Meadow Soils Formed On The Iii Underfladder Terrace Of Syrdarya, J.M. Kuziev

Irrigation and Melioration

Presents material on the geographical location, geomorphological and geological structure, as well as the agrochemical state of irrigated serozem-meadow soils, common in the Mirzaabad district of the Syrdarya region. According to the data obtained on the chemical analysis of soils, the studied soils are medium- and heavily loamy in texture, where particles of coarse sand predominate (0.05-0.01%). In the arable horizon of these soils, the humus content is 1.088-1.214%, total nitrogen 0.079-0.089%, total phosphorus 0.109-0.124%, and total potassium within 1.15-1.24%, and on the basis of these data, a regularity of the underlying horizon of these soils. The degree of provision …


Comparative Analyses Of Variable And Fixed Rate Irrigation And Nitrogen Management For Maize In Different Soil Types: Part I. Impact On Soil-Water Dynamics And Crop Evapotranspiration, Vasudha Sharma, Suat Irmak Nov 2020

Comparative Analyses Of Variable And Fixed Rate Irrigation And Nitrogen Management For Maize In Different Soil Types: Part I. Impact On Soil-Water Dynamics And Crop Evapotranspiration, Vasudha Sharma, Suat Irmak

Biological Systems Engineering: Papers and Publications

Understanding the soil-water dynamics and maize evapotranspiration (ETc) under variable rate irrigation (VRI) and variable rate fertigation (VRF) management with respect to soil spatial variability constitutes the basis for developing effective variable rate water and nitrogen management strategies. This long-term research was designed to quantify and compare the soil-water dynamics, including available water (AW), and ETc during vegetative and reproductive growth periods of VRI, fixed rate irrigation (FRI) and no-irrigation (NI) under fixed rate fertigation (FRF), VRF and pre-plant (PP) nitrogen management in three different soil types [Crete silt loam (S1); Hastings silty clay loam (S2) and Hastings silt loam …


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

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 …


Crop Canopy Sensor Orientation For Late Season Nitrogen Determination In Corn, T. M. Shaver, Greg Kruger, Daran Rudnick Jan 2017

Crop Canopy Sensor Orientation For Late Season Nitrogen Determination In Corn, T. M. Shaver, Greg Kruger, Daran Rudnick

Biological Systems Engineering: Papers and Publications

Increasing nitrogen use efficiency (NUE) in irrigated corn production is of great importance to overall agricultural sustainability. Studies have shown that crop canopy sensors can aid in this pursuit as they allow for the determination of nitrogen (N) requirements in split applications later in the growing season. Fertigation can also increase NUE as many split applications can be conducted. If crop canopy sensors could be used to direct N fertigation rates, overall NUE may be increased even further. However, in some cases, N differences may need to be determined later in the growing season after corn has tasseled, which can …


Runoff Water Quality Characteristics Following Swine Slurry Application Under Broadcast And Injected Conditions, Nicole R. Schuster, Shannon L. Bartelt-Hunt, Lisa M. Durso, John E. Gilley, Xu Li, David B. Marx, Amy M. Schmidt, Daniel D. Snow Jan 2017

Runoff Water Quality Characteristics Following Swine Slurry Application Under Broadcast And Injected Conditions, Nicole R. Schuster, Shannon L. Bartelt-Hunt, Lisa M. Durso, John E. Gilley, Xu Li, David B. Marx, Amy M. Schmidt, Daniel D. Snow

Biological Systems Engineering: Papers and Publications

This study was conducted to measure the effects of swine slurry application method, time following slurry application, and runoff rate on selected water quality characteristics. Slurry from a commercial swine operation was broadcast or injected on field plots at a rate required to meet annual nitrogen requirements for corn. Rainfall simulation tests were conducted at five varying periods following slurry application. During each study period, three simulated rainfall events, separated by 24 h intervals, were applied for 30 min duration at an intensity of approximately 70 mm h-1. Following the third rainfall simulation event, inflow was applied at …


Removal Of Cattle Manure Constituents In Runoff From No-Till Cropland As Affected By Setback Distance, John E. Gilley, Aaron J. Sindelar, Brian L. Woodbury Jan 2016

Removal Of Cattle Manure Constituents In Runoff From No-Till Cropland As Affected By Setback Distance, John E. Gilley, Aaron J. Sindelar, Brian L. Woodbury

Biological Systems Engineering: Papers and Publications

Vegetative filter strips located at the bottom of a hillslope have been shown to substantially reduce nutrients and sediment in runoff. Cropland areas could serve a similar function. However, little scientifically derived information is available to help identify the setback distances required 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 the concentrations and mass transport rates of selected constituents following land application of beef cattle manure to a no-till cropland area. The study site had a residue cover of 8.84 Mg ha-1 …


Removal Of Cattle Manure Constituents In Runoff From No-Till Cropland As Affected By Setback Distance, John E. Gilley, Aaron J. Sindelar, Bryan L. Woodbury Jan 2016

Removal Of Cattle Manure Constituents In Runoff From No-Till Cropland As Affected By Setback Distance, John E. Gilley, Aaron J. Sindelar, Bryan L. Woodbury

Biological Systems Engineering: Papers and Publications

Vegetative filter strips located at the bottom of a hillslope have been shown to substantially reduce nutrients and sediment in runoff. Cropland areas could serve a similar function. However, little scientifically derived information is available to help identify the setback distances required 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 the concentrations and mass transport rates of selected constituents following land application of beef cattle manure to a no-till cropland area. The study site had a residue cover of 8.84 Mg ha …


Impact Of Water And Nitrogen Management Strategies On Maize Yield And Water Productivity Indices Under Linear-Move Sprinkler Irrigation, Daran Rudnick, Suat Irmak Jan 2013

Impact Of Water And Nitrogen Management Strategies On Maize Yield And Water Productivity Indices Under Linear-Move Sprinkler Irrigation, Daran Rudnick, Suat Irmak

Biological Systems Engineering: Papers and Publications

With uncertainty in future irrigation water availability and regulations on nutrient application amounts, experimentally determined effects of “controllable” management strategies such as nitrogen (N), water, and their combination on crop water productivity (CWP, also known as crop water use efficiency) and actual evapotranspiration (ETa) are essential. The effects of various N application rates (0, 84, 140, 196, and 252 kg ha-1) under fully irrigated (FIT), limited irrigation (75% FIT), and rainfed conditions on maize (Zea mays L.) yield and various CWP indices were investigated in 2011 and 2012 growing seasons under linear-move sprinkler irrigation in south …


Runoff Nutrient Transport As Affected By Land Application Method, Swine Growth Stage, And Runoff Rate, J. E. Gilley, Shannon L. Bartelt-Hunt, S. J. Lamb, X. Li, D. B. Marx, D. D. Snow, D. B. Parker, B. L. Woodbury Jan 2013

Runoff Nutrient Transport As Affected By Land Application Method, Swine Growth Stage, And Runoff Rate, J. E. Gilley, Shannon L. Bartelt-Hunt, S. J. Lamb, X. Li, D. B. Marx, D. D. Snow, D. B. Parker, B. L. Woodbury

Biological Systems Engineering: Papers and Publications

This study was conducted to measure the effects of slurry application method, swine growth stage, and flow rate on runoff nutrient transport. Swine slurry was obtained from production units containing grower pigs, finisher pigs, or sows and gilts. The swine slurry was applied using broadcast, disk, or injection methods at a rate required to meet annual nitrogen requirements for corn. Three 30 min simulated rainfall events, separated by 24 h intervals, were applied to the experimental plots at an intensity of 70 mm h-1. Inflow was applied at the top of each plot in four successive increments after …