Physical Sciences and Mathematics Commons^™

Field Research Report: Results From The Enreec Vri Field For The 2021, 2022, And 2023 Crop Seasons, Derek M. Heeren, Ali T. Mohammed, Eric Wilkening, Christopher M. U. Neale, Alan L. Boldt, Ankit Chandra, Precious Nneka Amori, Ivo Z. Goncalves, Yeyin Shi, Guillermo R. Balboa

Department of Biological Systems Engineering: Conference Presentations and White Papers

Long-term irrigation management research has been conducted from 2014 to 2023 for corn and soybean at the Eastern Nebraska Research, Extension, and Education Center (ENREEC) Variable Rate Irrigation (VRI) Field located in subhumid east-central Nebraska (in the Lower Platte North Natural Resources District). The objective of this report was to present the overall results from the VRI Field for 2021 to 2023. Across the three growing seasons, there were the following irrigation treatments: Best Management Practice (BMP), 50% BMP, 125% BMP, rainfed, Spatial ET Modeling Interface (SETMI), SDD1, SDD2, machine-learning-based Cyber-Physical System (CPS), a student team recommended rate, and industry …

Pronghorn Survival And Resource Selection In Western Nebraska's Agriculturally Dominated Landscape, Katie Piecora

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

Nebraska’s pronghorn population has been stable over the last decade, yet their presence on the landscape remains a contentious subject amongst private landowners. Conversion of grassland for crop production and increased anthropogenic activity has drastically altered pronghorn behavior throughout their current range, however basic ecology and resource use by pronghorn in Nebraska remains poorly understood. Establishing baseline population metrics and seasonal patterns of resource use for this population at the eastern periphery of the species range is critical to guide management actions. We deployed GPS collars on 110 adult pronghorn to quantify survival, mortality risk, and seasonal resource selection in …

Human And Hydrologic Influences On Nebraska's Endangered Rainwater Basin Wetlands, Sarah Thompson

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

Over half of wetlands in North America have been lost or degraded. Rainwater Basin (RWB) wetlands, located in south-central Nebraska, are a primary example of such loss; an estimated 90% have been destroyed by land conversion for agriculture. Remaining RWB wetlands are often embedded in row-crop fields, where they are threatened by altered surface water runoff flow, drainage features, and excess sediment inputs. Efforts at the state and federal level have been made to preserve this wetland complex due to the critical stopover habitat these wetlands provide for migratory birds. Land managers work to maintain sufficient water levels during migratory …

A Long-Term Vision For An Ecologically Sound Platte River, Andrew J. Caven, Melissa M. Mosier, Kristal Stoner, Bill Taddicken, Brice Krohn, Ashley Gramza, Craig R. Allen, Mike Carter, Michelle Koch, Kirk D. Schroeder, Sarah Bailey, Rich Walters, Brian C. Chaffin, Erica Gnuse, Amy Jones, Kate Bird

Zea E-Books Collection

The Platte River extends about 310 mi (499 km) from North Platte, Nebraska, to its terminus at the Missouri River confluence near Plattsmouth, Nebraska. The Platte River Valley is a continentally significant ecosystem that serves as a major stopover for migratory waterbirds in the Central Flyway including the endangered Whooping Crane (Grus americana) and >1 million Sandhill Cranes (Antigone canadensis) at the peak of spring migration. However, the Platte River Valley also supports a great diversity of avifauna including grassland breeding birds, native stream fish, vascular plants, herpetofauna, mammals, pollinators, and aquatic macroinvertebrates. Despite ongoing conservation …

Analysis Of Soil Change Across Nebraska, Trinity Baker

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

The world’s population is growing and an increasing populace requires more resources. These requirements place increasing pressure on the environment and the soil. Soils serve many important functions throughout the world. These functions range from offering a media for food production, providing a sink for organic carbon, nutrient cycling, and improving water quality. It is important to focus on the human impact on soils and their change over time.

For my research I examined how soils across Nebraska have changed over a time period of roughly 65 years. I sampled and analyzed 39 pedons from four Major Land Resource Areas …

Multi-Criteria Evaluation Model For Classifying Marginal Cropland In Nebraska Using Historical Crop Yield And Biophysical Characteristics, Andrew Laws

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

Marginal cropland is suboptimal due to historically low and variable productivity and limiting biophysical characteristics. To support future agricultural management and policy decisions in Nebraska, U.S.A, it is important to understand where cropland is marginal for its two most economically important crops: corn (Zea mays) and soybean (Glycine max). As corn and soybean are frequently planted in a crop rotation, it is important to consider if there is a relationship with cropland marginality. Based on the current literature, there exists a need for a flexible yet robust methodology for identifying marginal land at different scales, which …

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 …

Public Access For Pheasant Hunters: Understanding An Emerging Need, Lyndsie S. Wszola, Anastasia E. Madsen, Erica F. Stuber, Christopher J. Chizinski, Jeffrey J. Lusk, J. Scott Taylor, Kevin L. Pope, Joseph J. Fontaine

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Ring‐necked pheasant (Phasianus colchicus; i.e., pheasant) hunting participation is declining across North America, reflecting a larger downward trend in American hunting participation and threatening benefits to grassland conservation and rural economies. To stabilize and expand the pheasant hunting population, we must first identify factors that influence pheasant hunter participation. We used an extensive in‐person hunter survey to test the hypothesis that hunter demographics interact with social‐ecological traits of hunting locations to affect hunter decisions, outcomes, and perceptions. We built a series of Bayesian mixed effects models to parse variation in demographics, perceptions, and hunt outcomes of pheasant hunters interviewed at …

Assessment Of The Ponderosa Woodlands In Nebraska's Wildcat Hills: Implications For Juniperus Encroachment And Management, Allie Victoria Schiltmeyer

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

Ponderosa pine (Pinus ponderosa) is a dominant tree species across western North America. Its eastern distribution includes three populations in western Nebraska. This study assesses the distribution, structure and age of ponderosa pine woodlands in one of those regions, the Wildcat Hills. The Wildcat Hills have escaped severe wildfires seen in recent decades in other ponderosa pine regions. Nevertheless, the Wildcat Hills woodlands face multiple threats including climate change, wildfire, drought, pine beetles, and invasive species. Key to these threats is the stand structure of pine woodlands, which have increased in density across much of ponderosa pine’s range. …

Wetland Conservation Effects Result In Enhanced Playa Functionality In The Rainwater Basin, Nebraska, Hong Zhang

Community and Regional Planning Program: Theses and Student Projects

This study assessed the functionality level of wetland hydrology, hydrophyte and soil conditions, and then identified the restorable potential of conserved playas. The distribution of hydrology and hydrophyte were geospatially examined through annual tracking the quantity and quality of wetlands on historical hydric soil footprints under different conservation programs in the Rainwater Basin (RWB) in Nebraska, USA during 2004-2015. The results show that the historical hydric soil footprints with the conservation programs had significantly higher functionality of ponded water and hydrophyte than non-conserved wetlands. The yearly average of ponded water areas within footprints varies at 12.59% for the Waterfowl Production …

The Long Term Effect Of Agricultural, Vadose Zone And Climatic Factors On Nitrate Contamination In Nebraska’S Groundwater System, Pongpun Juntakut, Daniel D. Snow, Erin M.K. Haacker, Chittaranjan Ray

Nebraska Water Center: Faculty Publications

A four-decade dataset (1974–2013) of 107,823 nitrate samples in 25,993 wells from western and eastern parts of Nebraska was used to assess long-term trends of groundwater nitrate concentration and decadal changes in the extent of groundwater nitrate-contaminated areas (NO₃-N≥10 mg N/L) over the entire state. Spatial statistics and regressions were used to investigate the relationships between groundwater nitrate concentrations and several potential natural and anthropogenic factors, including soil drainage capacities, vadose zone characteristics, crop production areas, and irrigation systems. The results of this study show that there is no statistically significant trend in groundwater nitrate concentrations …

River Otter (Lontra Canadensis) Distribution And Habitat Suitability In Nebraska, Nathan R. Bieber

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

River otters (Lontra Canadensis) were extirpated in Nebraska by the early 1900’s, but in 1986, the Nebraska Game and Parks Commission (NGPC) began reintroduction efforts. Following reintroductions, the otter was listed as a tier-1 at-risk species in Nebraska. With increasing otter populations, NGPC is evaluating a de-listing plan. In order to inform de-listing efforts, I surveyed Nebraska’s rivers documenting otter sign and used modeling techniques to estimate otter distribution and habitat suitability.

Otter sign surveys were conducted on the navigable rivers of Nebraska. Occupancy modeling techniques were used to examine patterns in otter detections. The best model incorporated distance …

The Effect Of Soil Ph On The Integument Of Western Tiger Salamanders, Aaron Devine, Dennis M. Ferraro

UCARE Research Products

This study was done in an effort to better understand the multifaceted issues in amphibian decline, specifically within the eastern regions of Nebraska, to determine whether or not human-induced acid rain contributed to the decline. This is a heavily important topic of research as amphibians worldwide are declining related to many issues that stem from climate change and several other environmental issues of that nature. This study looked to use acidic pH within soil from western Nebraska to determine the reactionary impacts (primarily lesions) the western tiger salamander had after being subjected to it. It was found that pH did …

The Influence Of A Severe Reservoir Drawdown On Springtime Zooplankton And Larval Fish Assemblages In Red Willow Reservoir, Nebraska, Jason A. Deboer, Christa M. Webber, Taylor A. Dixon, Kevin L. Pope

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Reservoirs can be dynamic systems, often prone to unpredictable and extreme waterlevel fluctuations, and can be environments where survival is difficult for zooplankton and larval fish. Although numerous studies have examined the effects of extreme reservoir drawdown on water quality, few have examined extreme drawdown on both abiotic and biotic characteristics. A fissure in the dam at Red Willow Reservoir in southwest Nebraska necessitated an extreme drawdown; the water level was lowered more than 6 m during a two-month period, reducing reservoir volume by 76%. During the subsequent low-water period (i.e., post-drawdown), spring sampling (April-June) showed dissolved oxygen concentration was …

A Historical Perspective On Nebraska’S Variable And Changing Climate, Martha Shulski, William Baule, Crystal J. Stiles, Natalie A. Umphlett

High Plains Regional Climate Center: Personnel Publications

Nebraska is situated at the intersection of the northern and southern Great Plains, exhibiting a dramatic longitudinal gradient for precipitation and humidity, and benefiting from groundwater resources. The continental climate is highly variable temporally both for temperature and precipitation. Our assessment of long-term meteorological observations shows that over the last century the annual average temperature in Nebraska has warmed approximately 0.6°C, which is similar to the increase in the global average temperature over the same time period. Furthermore, we found minimum temperatures have warmed more than maximum temperatures, and winter and spring show the strongest warming. We found no significant …

Pooling For Horizontal Wells: Can They Teach An Old Dog New Tricks?, Bruce M. Kramer

Shale Plays in the Intermountain West: Legal and Policy Issues (November 12)

74 pages.

This paper was originally published as:

Bruce M. Kramer, “Pooling for Horizontal Wells: Can They Teach an Old Dog New Tricks?,” 55 Rocky Mt. Min. L. Inst. 8-1, § 8.05 (2009).

Agenda: Shale Plays In The Intermountain West: Legal And Policy Issues, University Of Colorado Boulder. Natural Resources Law Center

Shale Plays in the Intermountain West: Legal and Policy Issues (November 12)

This one-day symposium to be held at the Grand Hyatt hotel in Denver will address the technology, economics, environmental impacts, and regulatory issues associated with shale gas development in the Rocky Mountain region. The purpose of this event is to facilitate productive dialogue among a wide range of stakeholders and interested parties to guide policy decisions.

Slides: Forest Service Planning At A Crossroads; New Approaches To Old Recommendations, Rick Cables

The Past, Present, and Future of Our Public Lands: Celebrating the 40th Anniversary of the Public Land Law Review Commission’s Report, One Third of the Nation’s Land (Martz Summer Conference, June 2-4)

Presenter: Rick Cables, Regional Forester, U.S. Forest Service - Rocky Mountain Region (Golden, CO)

23 slides

Slides: Rethinking Western Water Law: Restoring The Public Interest In Western Water Law, Mark Squillace

Western Water Law, Policy and Management: Ripples, Currents, and New Channels for Inquiry (Martz Summer Conference, June 3-5)

Presenter: Mark Squillace, Director, Natural Resources Law Center, University of Colorado Law School

20 slides

Slides: Water Towers In The Balance: Time For A New Water Project, Rick Cables

Western Water Law, Policy and Management: Ripples, Currents, and New Channels for Inquiry (Martz Summer Conference, June 3-5)

Presenter: Rick Cables, U.S. Forest Service, Rocky Mountain Region

9 slides

Slides: Unquenchable, Robert Glennon

Western Water Law, Policy and Management: Ripples, Currents, and New Channels for Inquiry (Martz Summer Conference, June 3-5)

Presenter: Robert Glennon, Morris K. Udall Professor of Law and Public Policy, James E. Rogers College of Law, University of Arizona

56 slides

Slides: Water Needs And Strategies For A Sustainable Future, Shaun Mcgrath

Shifting Baselines and New Meridians: Water, Resources, Landscapes, and the Transformation of the American West (Summer Conference, June 4-6)

Presenter: Shaun McGrath, Program Director, Western Governors’ Association

25 slides

Slides: Rethinking Western Water Law: Whatever Happened To The Public Interest?, Mark Squillace

Shifting Baselines and New Meridians: Water, Resources, Landscapes, and the Transformation of the American West (Summer Conference, June 4-6)

Presenter: Mark Squillace, Director, Natural Resources Law Center, University of Colorado Law School

15 slides

Slides: "Mitaku Oyasin" Means "We Are All Related", Bob Gough

Shifting Baselines and New Meridians: Water, Resources, Landscapes, and the Transformation of the American West (Summer Conference, June 4-6)

Presenter: Bob Gough, NativeEnergy, Inc.

72 slides

Factors Affecting Songbird Nest Survival And Brood Parasitism In The Rainwater Basin Region Of Nebraska, Max Post Van Der Burg

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

No abstract provided.

Vertical Movement Of Water In A High Plains Aquifer Induced By A Pumping Well, Xunhong Chen, Yanfeng Yin, James W. Goeke, Robert F. Diffendal Jr.

School of Natural Resources: Faculty Publications

Field observation and numerical simulations were carried out to evaluate the hydraulic relationship between the shallow and deep aquifer of a High Plains Aquifer system, in which shallow and deep aquifers are separated by an aquitard. Pumping from the lower aquifer resulted in a small drawdown in the upper aquifer and a larger drawdown in the aquitard; pumping from the shallow aquifer caused a small drawdown in the aquitard and the deep aquifer. Analysis of pumping test data gives the values of the hydraulic conductivity of the aquitard and the deep aquifer. Long-term observation of groundwater levels in the shallow …

Vertical Movement Of Water In A High Plains Aquifer Induced By A Pumping Well, Xunhong Chen, Yanfeng Yin, James W. Goeke, Robert F. Diffendal Jr.

Department of Earth and Atmospheric Sciences: Faculty Publications

Field observation and numerical simulations were carried out to evaluate the hydraulic relationship between the shallow and deep aquifer of a High Plains Aquifer system, in which shallow and deep aquifers are separated by an aquitard. Pumping from the lower aquifer resulted in a small drawdown in the upper aquifer and a larger drawdown in the aquitard; pumping from the shallow aquifer caused a small drawdown in the aquitard and the deep aquifer. Analysis of pumping test data gives the values of the hydraulic conductivity of the aquitard and the deep aquifer. Long-term observation of groundwater levels in the shallow …

Mesopredator Movement, Abundance, And Habitat Selection In The Rainwater Basins Of Nebraska, Christina J. Kocer

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

No abstract provided.

Slides: Deep Trouble On The Plains: Conflicts Over Aquifer Mining, Management And Marketing, Ronald Kaiser

Groundwater in the West (Summer Conference, June 16-18)

Presenter: Ron Kaiser, Texas A&M University.

47 slides.

Slides: The Spokane And The Yakima: A Tale Of Two Aquifers, Rachel Paschal Osborn

Groundwater in the West (Summer Conference, June 16-18)

Presenter: Rachael Paschal Osborn, Private Practice and Gonzaga Law School.

89 slides.