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Drainage Area Limitations of Single Watershed, Peak Flow Estimates from NRCS Methods
No full textMost state Department of Transportation roadway design sections predict peak flow for culvert design using, amongst other approaches, Natural Resources Conservation Service (NRCS) TR-20 technology. Even though this technology is more than 50 years old, there are no clear guidelines for how large a single watershed drainage area may be while remaining appropriate for predicting peak discharge with this method. Our objective was to identify the drainage area where TR-20 peak flow predictions significantly deviate from flow frequency predictions. We developed flow frequency estimates for 130 small-area stream gage sites in rural Nebraska and compared the calculated return period discharges with those from TR-20 using both the segmental and lag equation approaches for estimating the time of concentration. Additionally, we compared available regression predictions to both flow frequency and TR-20 estimates.
We found that there are no significant differences between peak discharges calculated using the TR-20 lag method and segmental method for estimating the time of concentration. If TR-20 continues to be used in the future, we recommend using the segmental approach to be more consistent with commonly accepted practice. Results did show, however, that predictions are consistently higher than those from stream gage estimates and become worse for drainage areas larger than fifteen square miles. The regression equations developed for small drainage areas (perhaps uniquely available for Nebraska) perform better than the TR- 20 estimates. As a first step to further investigate the performance of the TR-20 equations, we made peak flow estimates assuming drier soil conditions that effectively reduce the runoff curve number for each watershed. Results again showed poor agreement, but instead of being consistently high, were consistently low. We therefore discourage using an uncalibrated TR-20 model to calculate peak flow for culvert design for any size drainage area in Nebraska. If peak discharge estimates are required for changing land use conditions, we recommend a TR-20 model be calibrated to the regression model results for present conditions, thus allowing the simulation of changed land use conditions easily done with TR-20.
Next generation hydrologic approaches such as the National Water Model and GEOGloWS currently lack the resolution required to simulate peak flows from smaller watersheds. Tests showed universally low estimates compared to gage estimates of return period discharges
2024 Founders Award Remarks
No full textThe NCHC Founders Award recipient emphasizes the transformative power of honors education and the importance of community.
Includes a revised version of remarks delivered at the 2024 National Collegiate Honors Council awards ceremony on November 1, 2024 in Kansas City, Missouri
Development of an Honors Leadership Academy Experience
No full textThis essay presents a leadership academy in honors, an interdisciplinary offering co-taught by a team of five faculty combining in-course curriculum with travel-based experiential learning. Authors describe the academy’s inception, development, and curricular objectives and outcomes, as well as the experiences of four student cohorts (2021–2024). Focusing on interdisciplinary approaches to community-based problem solving, students (n ≈ 8–14) learn the Social Change Model of Leadership Development framework; engage in self-reflective exercises relating to leadership values and attitudes; partner with a local nonprofit organization; use design thinking methodology to solve a specific organizational challenge; and collaboratively work in teams to find solutions to these problems. Using City as Text® pedagogy, traveling students are invited to be active participants in their learning. Students meet with paired community organizations that share missions similar to those of local partners. In this way, students gain new insights and perspectives on how best to address challenges presented in their immediate environments. Components of the annual academy framework are presented
Military Forensic Archaeology: The Process and Recovery of U.S. Missing-in-Action (MIA) Service Personnel
No full textThe United States (U.S.) Department of Defense\u27s (DoD) Defense POW/MIA Accounting Agency (DPAA) is the largest skeletal identification laboratory in the world and receives several hundred cases per year for identification related to Missing-in- Action (MIA) U.S. service members. While there are various sources for these accessions, by far the largest source is through unilateral or bilateral (done in cooperation with another governmental entity or nongovernmental organization) as well as public-private partnership excavations. While the DPAA-style military forensic archaeology follows archaeological principles and recording standards, the work is goal-oriented, evidence/trace-driven, and time-constrained— a common occurrence with cultural resource management sites or salvage/heritage archaeology throughout the world. The focus herein is to present the basic tenets and principles that guide the DPAA military forensic archaeologist in decision-making regarding items of relevance that assist the excavation process as well as guide the individual identification process once the field operations cease. DPAA forensic archaeologists use a mindset of flexibility of standard archaeological methods and principles. This flexibility is focused on these ideals, such that a large amount of surface area must be excavated in an extremely limited time. The forensic concepts of trace relevance and trace value at various levels (a “nested” approach) of site formation, time asymmetry, and biological identification are tied to these archaeological principles and context to support the goal of forensic identification of individual missing U.S. service personnel
Colony Collapse Disorder and How to Mitigate Losses
No full textWhat is Colony Collapse Disorder?
The Role of Varroa destructor in CCD
Viruses and Their Role in CCD
Effects of Nosema in CCD
Habitat Destruction/Nutrition and Its Effect on CCD
Pesticides and their effect on CCD
Mitigating Causes of CCD
Colony Behavior, Social Resilience, and Monitoring
Integrated Management Approaches
Conclusio
Honoring the First-year Seminar: Exploring High-impact Learning Experiences for the First Year in Honors: Front- and Backmatter
No full textFront-and backmatter from Honoring the First-year Seminar: Exploring High-impact Learning Experiences for the First Year in Honors (Lincoln, Nebraska: National Collegiate Honors Council, 2025)
The Motivation and Influence Behind the Decisions of High School Students to Participate in the National FFA Organization
No full textToday, high school students are increasingly engaged in extracurricular activities, navigating a diverse range of options for which clubs and organizations to join during their secondary education. This poses a challenge for students and for Career and Technical Student Organizations as they work to recruit talented students. High school students have several influences and pressures on their time, including peers, family, and teachers. These influences often recognize how organizations such as FFA can be pivotal in shaping students’ personal and professional development. We wanted to explore the motivations and influences guiding high school students’ decisions to join and actively participate in FFA. Employing an exploratory case study approach, this research focused on two Midwest high schools to understand the influences shaping students’ engagement in FFA. We found that a range of motivations, including personal relationships, culture, and future career opportunities, influenced students’ decisions. These findings have implications for agricultural education teachers and others in the agricultural community, helping them understand what motivates students and how students perceive the benefits and value of their participation within the organization
Understanding the Tyson Lexington Plant Closure: What It Means for Cattle Producers
No full textOn Nov. 21, Tyson Foods announced it would permanently close its beef processing facility in Lexington, Nebraska, effective Jan. 20. The company also announced it would convert its Amarillo, Texas, facility to a single full-capacity shift. The Lexington plant employs roughly 3,200 people and can slaughter almost 5,000 cattle per day approximately 4.8% of total daily U.S. beef slaughter. This marks the first time one of the Big Four meatpacking companies has permanently closed a major plant during the current cattle supply crunch.
Markets have reacted quickly. On Nov. 24, live cattle futures fell the 9.25 limit across the board. Cash fed cattle trade the week prior came in at 4-5) and 7). The CME Feeder Cattle Index stood at 10-20 lower for 700-800 lb. steers and $20-40 lower for 500-600 lbs. steers last week.
The purpose of this article is to explain what the Lexington plant’s closure could potentially mean for cattle producers in Nebraska and beyond, how it compares to previous plant disruptions in the last 5-7 years, what economic research tells us about potential price impacts of such a closure
Evaluation of RAMP Instead of Forage during Grain Adaptation and Different Sorghum Varieties on Enteric Methane Production from Cattle
No full textTwo experiments were conducted to evaluate the use of RAMP (Cargill Corn Milling, Blair, Nebraska) compared with traditional forage-based adaptations on methane (CH4) and carbon dioxide (CO2) emissions, performance, and carcass characteristics. Experiment 1, 64 yearling British × Continental steers (initial BW = 423 ± 6 kg) were adapted using 100% RAMP (RAMP) or a traditional forage diet (CON; 43% forage) before transitioning 22 d to a common finishing diet containing 65.6% steam-flaked corn. Emissions were measured in paired replications using a two-chamber indirect calorimetry barn. During adaptation RAMP did not affect CH4 production (g/d; P = 0.66), CH4:CO2 (P = 0.71), CO2 (P = 0.92), or DMI (P = 0.77). However, on the common finishing diet, RAMP-adapted steers tended to produce 8% less CH4 (g/d; P = 0.10) and reduced CH4:CO2 (P = 0.03). RAMP steers had lighter HCW (450 vs. 456 kg; P = 0.06) and tendencies for reduced ADG (P = 0.06) and G:F (P = 0.11).
Experiment 2 utilized 64 similar steers (initial BW = 517 ± 0.9 kg) adapted with RAMP or forage to diets containing 51% or 71% steam-flaked corn. During adaptation, CH4 (g/d) did not differ (P = 0.37), although CH4:CO2 was reduced for RAMP (P = 0.05). No differences occurred in CO2 (P = 0.18) or DMI (P = 0.26). During the finishing period, CH4 (g/d; g/kg DMI) and CH4:CO2 did not differ between treatments (P ≥ 0.25). RAMP-adapted steers had lighter HCW (462 vs. 467 kg; P = 0.02) and reduced final BW (P = 0.02).
A 169-d finishing experiment evaluated five dry-rolled sorghum grain varieties (X54346, AG1203, SP68M57, G38, and 341X120) compared with a dry-rolled corn control using indirect calorimetry. CH4 g/kg DMI did not differ among varieties, although variety 5 produced 22% less CH4 (g/d) than variety 2. CH4:CO2 ratios were similar, but variety 4 was numerically lowest. Feeding sorghum for the first 100 d increased DMI (P = 0.02) without affecting ADG or G:F (P ≥ 0.25).
Advisor: Galen E. Erickso
Art TEAMS: Teaching with Arts and Emerging Media Year 3 Infographic
Full text linkGrant annual report, year 3, infographic
Universty of Nebraska-Lincoln, 2025
Art TEAMS, Year 3: Supporting K-12 Teachers through the Integration of Arts-centered Practices and Emerging Medi