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Articles 1 - 21 of 21

Full-Text Articles in Physical Sciences and Mathematics

Microdialysis: A Method For Quantifying In Situ Nitrogen Fluxes In Soil Microsites, Srusti Maddala, Mary C. Savin, Julie A. Stenken, Lisa S. Wood Jan 2020

Microdialysis: A Method For Quantifying In Situ Nitrogen Fluxes In Soil Microsites, Srusti Maddala, Mary C. Savin, Julie A. Stenken, Lisa S. Wood

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Microdialysis, a diffusion-based sampling technique commonly used in biomedical research, has recently been recognized as a candidate for monitoring chemical changes in the rhizosphere. The information it provides about nutrient diffusion may improve nitrogen use efficiency, leading to enhanced management and success of restoration projects. The objective of this study was to determine the efficacy of microdialysis sampling to quantify the relative recoveries (RR%) of nitrate-N and ammonium-N, the two inorganic nitrogen compounds typically found in soil. The effects of microdialysis flow rate, sample medium concentration, and the presence of both analytes in solution on the relative recoveries obtained from …


Corn Response To Wastewater-Recycled Phosphorus Fertilizers, Shane R. Ylagan, Kristofor R. Brye Jan 2020

Corn Response To Wastewater-Recycled Phosphorus Fertilizers, Shane R. Ylagan, Kristofor R. Brye

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

The ability to recycle phosphorus (P) from wastewaters could provide a sustainable, continuous source of P that might also help protect surface water quality from P enrichment. The mineral struvite (MgNH4PO4 · 6H2O) is an understudied material that can be created from P- and nitrogen (N)-containing wastewater and has been shown to have agricultural fertilizer value. The objective of this study was to evaluate the effects of electrochemically precipitated struvite (ECST), chemically precipitated struvite (Crystal Green; CG), diammonium phosphate (DAP), monoammonium phosphate (MAP), rock phosphate (RP), and triple superphosphate (TSP) on corn (Zea mays) response in a greenhouse pot study. …


Anthocyanin Stability In Food Products Made With Freeze-Dried Blueberry Powder, Samantha R. Findley, Luke Howard Jan 2019

Anthocyanin Stability In Food Products Made With Freeze-Dried Blueberry Powder, Samantha R. Findley, Luke Howard

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

This study evaluated the stability of anthocyanins in six blueberry products (gummy, graham bar, oatmeal bar, rice krispy bar, ice pop and juice) prepared with freeze-dried wild blueberry powder during processing and over eight weeks storage. Total anthocyanins were determined by HPLC before processing and at day 0 and 2, 4, 6, and 8 weeks of storage. Thermal processing of gummy and graham bar products resulted in losses of anthocyanins (50 and 31%, respectively). An eight-week storage time also resulted in a decrease in anthocyanins (7 to 51%) in products stored at ambient temperature. The ice pop, which was stored …


The Effect Of Turning Frequency On In-Vessel Compost Processing And Quality, Paige E. Boyle, Mary C. Savin, Lisa S. Wood Jan 2015

The Effect Of Turning Frequency On In-Vessel Compost Processing And Quality, Paige E. Boyle, Mary C. Savin, Lisa S. Wood

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Composting can contribute to the zero waste initiative on the University of Arkansas (UA) campus. In-vessel systems like Earth Tubs™ are purported to provide better control of temperature and moisture during the composting process. Turning materials helps facilitate microbial activity and thermophilic composting. The goal of this research was to determine if turning frequency affects processing or final quality of compost made with pre- and post-consumer food waste feedstock and a wood chip bulking agent. Turning frequencies (treatment) of 3 days/week and 7 days/ week were evaluated simultaneously throughout three sequential runs. Temperature, pH, electrical conductivity (EC), and moisture content …


Reducing Water Extractable Phosphorus In Poultry Litter Using Chitosan Treatment, Zachary Simpson, Brina Smith, David A. Zaharoff, Brian E. Haggard Jan 2014

Reducing Water Extractable Phosphorus In Poultry Litter Using Chitosan Treatment, Zachary Simpson, Brina Smith, David A. Zaharoff, Brian E. Haggard

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Phosphorus (P) is an important factor in the eutrophication of freshwater, and watershed sources include effluent discharges and the landscape. Poultry litter applied to the landscape can be a potential source of P, which is dependent on rainfall, runoff and dissolution. Chitosan, the deacetylated form of the biopolymer chitin, has been shown to have an effect on reducing water extractable phosphorus (WEP) in poultry litter when applied as a powder. The intent of this study was to measure the effect that poultry litter treatment (PLT), acetic acid and incubation time have on chitosan’s ability to reduce WEP in poultry litter. …


The Influences Of Poultry Litter Biochar And Water Source On Radish Growth And Nutrition, Julia Allen, David E. Longer, Edward E. Gbur, Lichen Hao Jan 2014

The Influences Of Poultry Litter Biochar And Water Source On Radish Growth And Nutrition, Julia Allen, David E. Longer, Edward E. Gbur, Lichen Hao

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Many row-crop fields today have declined in soil fertility due to poor management practices and overuse of pesticides. Under these conditions, plant nutrient uptake can be sub-optimal. There are several soil amendments that can be used to improve soil quality and plant growth. This study focused on the addition of biochar to the soil and the use of structured water to enhance plant growth. Biochar is produced by pyrolysis of organic feedstocks. Previous studies which focused on biochar have shown an increase in plant yield, nutrient availability in the soil, and soil water holding capacity. Structured water is the liquid …


Influence Of Organic Groundcovers On Mycorrhizal Colonization And Symbiosis Of Organically Managed Fruit Crops, Raven Anai Bough, Curt R. Rom Jan 2013

Influence Of Organic Groundcovers On Mycorrhizal Colonization And Symbiosis Of Organically Managed Fruit Crops, Raven Anai Bough, Curt R. Rom

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Ground covers have the potential to impact the crop rhizosphere biology, which includes organisms such as arbuscular mycorrhizal fungi (AMF), which in turn affect the crop host plant through symbiosis. There has been evidence that a ground cover that provides a suitable environment for colonization of AMF and subsequent symbiosis could be a tool in organic fruit production. The objective of this research was to compare colonization of AMF in strawberry plant (Frageria x ananassa cv. Radiance) and apple rootstocks (Malus x domestica, cv. M. 26) grown in a greenhouse affected by various ground cover treatments. Inoculation was achieved by …


The Influence Of Poultry Litter Biochar On Early Season Cotton Growth, Taylor D. Coomer, David E. Longer, Derrick M. Oosterhuis, Dimitra A. Loka Jan 2013

The Influence Of Poultry Litter Biochar On Early Season Cotton Growth, Taylor D. Coomer, David E. Longer, Derrick M. Oosterhuis, Dimitra A. Loka

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Cotton is known for being sensitive to cool, wet soils, especially in the early stages of growth. Amendments to soil can aid cotton seedlings in development and nutrient uptake. However, soil amendments can be costly and detrimental to the environment, and alternatives such as the addition of biochar have been considered. Biochar is produced from biomass that has gone through pyrolysis and has been shown to improve plant yield, microbial response, soil structure, soil cation–exchange capacity, and water use efficiency. This study was conducted to evaluate the effect of biochar on early season cotton growth. The aim of this study …


Short-Term Denitrification In The Metalimnion Of A Eutrophic Reservoir, Aki Kogo, Erin M. Grantz, Thad Scott Jan 2013

Short-Term Denitrification In The Metalimnion Of A Eutrophic Reservoir, Aki Kogo, Erin M. Grantz, Thad Scott

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Denitrification in metalimnetic water was examined under different conditions to determine how addition of nitrate (NO3 -) and particulate carbon (PC), aeration, and concentrations of nitrate affect denitrification. In the first experiment, water samples from a metalimnion were treated with different combinations of NO3 - and PC. Changes in excess N2 -N concentration for 10 days were measured using membrane inlet mass spectrometry (MIMS). The second experiment used the same treatments as the first experiment after aeration of water. Besides excess N2 -N concentrations, O2 concentrations were measured for 16 days. The third experiment examined how different initial concentrations of …


Evaluation Of Cover Crops In High Tunnel Vegetable Rotation, Tyler A. Patrick, Neal Mays, Jason Mcafee, Curt R. Rom Jan 2013

Evaluation Of Cover Crops In High Tunnel Vegetable Rotation, Tyler A. Patrick, Neal Mays, Jason Mcafee, Curt R. Rom

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Organic vegetable production within high tunnels allows for an extended growing season, crop protection, and environmental control. The USDA National Organic Program (NOP) standards mandate evidence that the soil has been maintained and improved over the course of production. Previous studies have indicated the potential of cover crops for reducing competitive vegetation, and improving soil quality, thus resulting in greater plant growth, nutrient uptake, and yield. However, there has been limited work in the confines of high tunnels as part of a tunnel-system rotation. Ten nitrogen-fixing and ten non-legume cover crops were established under a high tunnel and evaluated for …


Assessment Of Students’ Crisis Communications Skill Increase Based On Classroom Instruction And Second Life™ Training, Gregory C. Jernigan, Jessica R. England, Leslie D. Edgar Jan 2013

Assessment Of Students’ Crisis Communications Skill Increase Based On Classroom Instruction And Second Life™ Training, Gregory C. Jernigan, Jessica R. England, Leslie D. Edgar

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Crisis communication training and skill development are critical to ensure the sustainability of the agriculture industry. The purpose of this study was to assess students’ perceptions of knowledge, ability, and skills on select crisis-related skills, tasks, and activities in order to identify the potential effectiveness of a Second LifeTM (SL) simulation. Pre- and post-test data were collected to determine the potential changes in skill in the seven crisis communication constructs of (a) related knowledge; (b) mass, group, and intrapersonal communications; (c) contingency planning; (d) use of related supplies and tools; (e) identifying learning and training needs; (f) related areas of …


Factors That Contribute To Turbidity On The West Fork Of The White River In Arkansas, Chris Cotton, Brian Haggard Jan 2011

Factors That Contribute To Turbidity On The West Fork Of The White River In Arkansas, Chris Cotton, Brian Haggard

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

The West Fork of the White River (WFWR) exceeds the water quality standard for turbidity (10 NTU) set by the Arkansas Department of Environmental Quality and, since 1998, the river has been on Arkansas’s 303 (d) list of impaired water bodies unsuitable for aquatic life because of turbidity exceedances. To understand the factors that could be related to turbidity, total suspended solids (TSS), total inorganic suspended solids (TISS), total volatile suspended solids (TVSS), sestonic chlorophyll-a (Chl-a) concentrations, and turbidity were measured on three sample dates from nine sites on the WFWR. As the site location changed in the downstream direction, …


Plant Growth In Soil Amended With Drilling Mud, Satoshi Takaki, Duane C. Wolf Jan 2011

Plant Growth In Soil Amended With Drilling Mud, Satoshi Takaki, Duane C. Wolf

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Extraction of natural gas generates drilling fluid and drilling mud that contain high concentrations of salts. Land application of the fluid and mud can have negative impacts on plant growth and soil properties. The objective of this study was to determine the effects of drilling mud on plant growth, plant chemical concentrations, and soil chemical properties. Sudangrass (Sorghum sudanense [Piper] Stapf [Piper]) and bermudagrass (Cynodon dactylon L.) were grown in a Roxana loam soil amended with 0%, 5%, or 10% (w/w) drilling mud in a 6-wk greenhouse study. Plant biomass production and concentrations of elements in biomass were determined. Electrical …


Effects Of Diesel And Biodiesel Blends On Engine Performance And Efficiency, Christopher Hunt, Donald Johnson, Don Edgar Jan 2010

Effects Of Diesel And Biodiesel Blends On Engine Performance And Efficiency, Christopher Hunt, Donald Johnson, Don Edgar

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Tests were conducted during the summer of 2009 on a John Deere 3203 diesel tractor to determine differences in specific fuel consumption (sfc), power take-off (PTO) torque (Nm), and PTO power (kW), between ultralow sulfur No. 2 Diesel (D2), 20% biodiesel (B20), 50% biodiesel (B50), and100% biodiesel (B100). Four 1-hr tests were conducted with D2, while three 1-hr tests were conducted with B20, B50, and B100. The results indicated that there was no significant (p < 0.05) difference between D2 and B20 for power or torque. Fueling with B50 resulted in significantly lower power and torque than fueling with D2 or B20, but significantly higher power and torque than fueling with B100. There were significant differences between each fuel in sfc; as the biodiesel blend increased, sfc also increased. Based on these data, B20 appears to be the optimal biodiesel blend for this and similar compact utility tractors since fueling with B20 resulted in no significant loss in power or torque (compared to D2) and only a slight increase in fuel consumption.


Evaluation Of Water-Retention Ability Of Eastern Arkansas Prairie And Agricultural Soil, Maria L. Barrenechea, Kristofor R. Brye Jan 2006

Evaluation Of Water-Retention Ability Of Eastern Arkansas Prairie And Agricultural Soil, Maria L. Barrenechea, Kristofor R. Brye

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Agricultural land use affects soil physical properties, such as bulk density, water content, organic matter content, and soil structure; all of which in turn affect ecosystem productivity. The objective of this study was to evaluate the effects of: 1) time since aboveground biomass has been removed by haying (i.e., 0 vs. 23 years), and 2) land use (i.e., undisturbed tallgrass prairie vs. cultivated agriculture) on water-retention characteristics in a silt-loam soil of the Grand Prairie region of eastern Arkansas. Soil samples were collected from the 0- to 10-cm depth and were wetted with varying amounts of distillated water to create …


Method Analysis Of Laboratory Measures Of Stream Sediment And Water Phosphorus Equilibrium, Anna L. Erickson, Stephanie M. Williamson, Brian E. Haggard Jan 2004

Method Analysis Of Laboratory Measures Of Stream Sediment And Water Phosphorus Equilibrium, Anna L. Erickson, Stephanie M. Williamson, Brian E. Haggard

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Elevated phosphorus concentrations in aquatic ecosystems of northwest Arkansas prompted an investigation of the effects of sample preparation and extraction methods on laboratory measures of sediment-phosphorus interactions. Two streams of contrasting phosphorus (P) concentrations were selected to determine the effect of using a CaCl2 solution instead of filtered stream water, refrigerated or dried sediments instead of fresh wet sediments, and vortexing the suspensions instead of shaking them. Sediment equilibrium P concentration (EPC0) and P buffering capacity (K) were used to determine differences in extraction methods. EPC0 and K from extractions using fresh sediments and a CaCl2 solution matching the electrical …


Assessment And Restoration Of A Neighborhood Wetland Invaded By Exotic Plant Species, Ryan Neal, Kimberly R. Payne, Lorena Moreno, Graham Duffy, Jonathan Peck, Mary C. Savin Jan 2004

Assessment And Restoration Of A Neighborhood Wetland Invaded By Exotic Plant Species, Ryan Neal, Kimberly R. Payne, Lorena Moreno, Graham Duffy, Jonathan Peck, Mary C. Savin

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

The University of Arkansas Crop, Soil, and Environmental Sciences (CSES) Club adopted a local wetland in the spring of 2002 through the Fayetteville Parks and Recreation Department. This project has allowed students to interact with local community and governmental organizations as well as other academic departments within the university. Students have gained valuable laboratory and field experience through characterizing hydric soils, identifying bird and plant species, and analyzing water quality, soil nutrients, and microbial biomass. Under the main goal of restoring the wetland, the club has outlined both short and long-term objectives including soil and water assessments; removal of two …


Laboratory-Scale Evaluation Of Incandescent And Compact Florescent Lamps For Poultry House Lighting, Leanne Gabriel, Donald M. Johnson Jan 2004

Laboratory-Scale Evaluation Of Incandescent And Compact Florescent Lamps For Poultry House Lighting, Leanne Gabriel, Donald M. Johnson

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

This laboratory-scale study compared 1000- and 2000-h rated 60W incandescent lamps and 6000-h rated 60W-equivalent compact florescent lamps over 6000 h of simulated broiler-house operation. The four original 1000-h incandescent lamps were replaced 22 times and the four 2000-h incandescent lamps were replaced 14 times. None of the four compact florescent lamps failed during the 6000-h experiment, although one was broken due to human error. Both types of incandescent lamps had significantly higher (p < .0001) mean illuminance (lx) than did the compact florescent lamps. The compact florescent lamps used significantly less (p < .0001) power (W) and had significantly higher (p < .0001) efficiency (lx/W) than the incandescent lamps. Despite a higher initial purchase price, the total cost (purchase + replacement + electrical) of operating compact florescent lamps was approximately 36% lower than the total cost of operating either type of incandescent lamp over the 6000 h period. The results of this study indicate that even at a least-cost price for electricity ($0.04/kW/h), growers can reduce total broilerhouse lighting costs by replacing incandescent lamps with compact florescent lamps.


Characterizing Bean Pod Rot In Arkansas And Missouri, Jeremy H. Taylor, Craig S. Rothrock Jan 2004

Characterizing Bean Pod Rot In Arkansas And Missouri, Jeremy H. Taylor, Craig S. Rothrock

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Green beans are an important crop grown for processing in both Arkansas and Missouri. Green beans are harvested mechanically using non-selective picking fingers. Harvested beans are then transported in bulk to processing plants that are located at various locations throughout the midSouth. Thus, the crop is managed for high quality, avoiding pod blemishes caused by insects and diseases. One of the consistent quality problems that affect Arkansas and Missouri green bean crops is pod rot. Two of the causal agents of pod rot that have been reported by researchers and vegetable companies alike are Pythium aphanidermatum and an unidentified Phytophthora …


Effects Of Vegetation Removal On Native Soil Quality In Eastern Arkansas, Lorena Moreno, Kristofor R. Brye Jan 2004

Effects Of Vegetation Removal On Native Soil Quality In Eastern Arkansas, Lorena Moreno, Kristofor R. Brye

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Aboveground vegetation removal practices, such as cutting and baling and burning, can both positively and negatively affect a prairie ecosystem. Burning can stimulate growth and species diversity, but removing vegetation and the nutrients it contains without equal replenishment of those nutrients could cause a steady decline in available soil nutrients. The objective of this study was to evaluate the effects of vegetation removal techniques in a native tallgrass prairie in eastcentral Arkansas. Soil samples were collected from the top 10 cm in each soil mapping unit that existed in each of three prairie areas that differed by the amount of …


Improvements In Turfgrass Color And Density Resulting From Comprehensive Soil Diagnostics, Matt Cordell, Jonathan Davis, David E. Longer Jan 2001

Improvements In Turfgrass Color And Density Resulting From Comprehensive Soil Diagnostics, Matt Cordell, Jonathan Davis, David E. Longer

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

There are roughly 220 golf courses in Arkansas, and as many as 50% of these courses were constructed using common bermudagrass fairways. Although resilient, common bermudagrass loses density and quality over time. In this experiment physical and chemical properties of the soil were analyzed to determine the causes of decline in turf quality observed on several fairways of a local golf course. Once a particular fairway was selected for study and preliminary soil sampling conducted, GS+, a geostatistical computer program, was used to map the location of certain chemical deficiencies. A moderate to severe Mg deficiency was detected throughout the …