Earth Sciences Commons^™

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 …

Using Drones In Agriculture

Daugherty Water for Food Global Institute: Administrative Materials

Unmanned aerial vehicles, known as “drones,” are increasingly popular for capturing aerial images. The United States Federal Aviation Administration eased their regulations for drone flights in June 2016, making drones more accessible for common use. Drones may supplement pre-existing imaging technology (e.g. satellites, manned aircraft, etc.). One case study in Nebraska found a niche application for drones. The participating producer used manned aerial imagery to identify potential problem spots in his fields. Then he used GPS navigation to direct the drone to more closely inspect the identified potential problem spots. This way the drone is not tasked with scouting entire …

Wireless Communications In Rural Areas

Daugherty Water for Food Global Institute: Administrative Materials

In many rural farming communities across America, wireless internet connectivity is a luxury. Absence of quality connectivity directly affects the adoption of new agricultural technologies, many of which require high-speed wireless connectivity to provide producers with accurate, real-time analytics. The current environment of spotty wireless internet connectivity in some rural areas negatively affects innovation and entrepreneurship in agriculture. In interviews with Nebraska farmers about internet-based technology, of the two farmers provided opposing views on connectivity. One young farmer said he avoids using precision agriculture technologies that run on wireless connectivity because his rural area lacks reliable service. He even talked …

Soil Moisture Probes

Daugherty Water for Food Global Institute: Administrative Materials

Just like fuel gauges monitor fuel levels in a gas tank, soil moisture sensors monitor moisture levels in the soil. Irrigating without using soil moisture sensors is similar to driving without a fuel gauge: you’re likely to be overcautious to ensure you get to where you’re going! Soil moisture probes are designed to estimate soil volumetric water content based on the dielectric constant of the soil. The dielectric constant can be thought of as the soil’s ability to transmit electricity. The dielectric constant of soil increases as the water content of the soil increases, since the dielectric constant of water …

Impacts: Annual Report Fy2018 (July 1, 2017 To June 30, 2018), Robert B. Daugherty Water For Food Global Institute

Daugherty Water for Food Global Institute: Administrative Materials

One in nine people goes to bed hungry each night, according to the U.N. World Food Program. That’s 795 million people on the planet who do not have access to enough nutritious food. The challenge is growing. Global drivers like climate change, urbanization and increasing demand for water-intensive agricultural products are altering landscapes, increasing soil erosion, and degrading water resources and soils in important food producing regions around the world. We must figure out how to feed a global population projected to reach 10 billion by 2050, with the same amount of water and arable land – and quickly. This …

Impact Of Grassland Conversion To Forest On Groundwater Recharge In The Nebraska Sand Hills, Zablon A. Adane, Paolo Nasta, Vitaly A. Zlotnik, David A. Wedin

Department of Earth and Atmospheric Sciences: Faculty Publications

Study region: Nebraska National Forest in the High Plains Aquifer, Nebraska Sand Hills, U.S.A. Study focus: This research aimed to investigate the effects of grassland conversions to forest on recharge rates in a century-old experimental forest. The DiffeRential Evolution Adaptive Metropolis (DREAM_ZS) global optimization algorithm was used to calibrate the effective soil hydraulic parameters from observed soil moisture contents for 220 cm deep uniform soil profiles. The historical recharge rates were then estimated by applying the numerical model HYDRUS 1-D for simulation of two plots representing grasslands and dense pine forest conditions. New hydrological insights: The results indicate …

Land-Cover Change And The ‘‘Dust Bowl’’ Drought In The U.S. Great Plains, Qi Hu, Jose Abraham Torres-Alavez, Matthew S. Van Den Broeke

Department of Earth and Atmospheric Sciences: Faculty Publications

The North American Dust Bowl drought during the 1930s had devastating environmental and societal impacts. Comprehending the causes of the drought has been an ongoing effort in order to better predict similar droughts and mitigate their impacts. Among the potential causes of the drought are sea surface temperature (SST) anomalies in the tropical Pacific Ocean and strengthened local sinking motion as a feedback to degradation of the land surface condition leading up to and during the drought. Limitations on these causes are the lack of a strong tropical SST anomaly during the drought and lack of local anomaly in moisture …

The Prairie Post Quarterly Newsletter Of The High Plains Regional Climate Center- January 2018, Natalie Umphlett, Crystal J. Stiles

Prairie Post: Quarterly Newsletter of the High Plains Regional Climate Center

Inside this issue:

Message from the interim director........................................1

Weather photo of the quarter.................................................. 1

2017 - year in review..............2

2017 climate in the High Plains............................................3

Update on La Niña..................3

Update on regional climate conditions..................................4

Product Highlight....................4

HPRCC Turns 30........................5

Recent and upcoming travel and activities.............................6

Sheeting Joints And Polygonal Patterns In The Navajo Sandstone, Southern Utah: Controlled By Rock Fabric, Tectonic Joints, Buckling, And Gullying, David Loope, Caroline M. Burberry

Department of Earth and Atmospheric Sciences: Faculty Publications

Sheeting joints are ubiquitous in outcrops of the Navajo Sandstone on the west-central Colorado Plateau, USA. As in granitic terrains, these are opening- mode fractures and form parallel to land surfaces. In our study areas in south-central Utah, liquefaction during Jurassic seismic events destroyed stratification in large volumes of eolian sediment, and first-order sheeting joints are now preferentially forming in these structureless (isotropic) sandstones. Vertical cross-joints abut the land-surface-parallel sheeting joints, segmenting broad (tens of meters) rock sheets into equant, polygonal slabs ~5 m wide and 0.25 m thick. On steeper slopes, exposed polygonal slabs have domed surfaces; eroded slabs …

Groundwater Withdrawals Under Drought: Reconciling Grace And Land Surface Models In The United States High Plains Aquifer, Wanshu Nie, Benjamin Zaitchik, Matthew Rodell, Sujay V. Kumar, Martha C. Anderson, Christopher Hain

United States National Aeronautics and Space Administration: Publications

Advanced Land Surface Models (LSM) offer a powerful tool for studying hydrological variability. Highly managed systems, however, present a challenge for these models, which typically have simplified or incomplete representations of human water use. Here we examine recent groundwater declines in the US High Plains Aquifer (HPA), a region that is heavily utilized for irrigation and that is also affected by episodic drought. To understand observed decline in groundwater and terrestrial water storage during a recent multiyear drought, we modify the Noah-MP LSM to include a groundwater irrigation scheme. To account for seasonal and interannual variability in active irrigated area, …

Assessing The Impact Of The Conservation Reserve Program On Honey Bee Health, Otto, C.R.V., O'Dell, S., Bryant, R.B., Euliss, N.H., Bush

United States Geological Survey: Publications

Insect pollinators are critically important for maintaining U.S. food production and ecosystem health. The upper Midwest is home to more than 40 percent of all U.S. honey bee colonies and is considered by many beekeepers to be America’s last beekeeping refuge. Beekeepers come to this region because their honey bees require high-quality grassland and bee-friendly agricultural crops to make honey and to improve bee health. Agricultural grassland, such as those enrolled in the Conservation Reserve Program (CRP), support flowers that provide bees with the pollen and nectar they need. In 2014, the U.S. Department of Agriculture (USDA) and the U.S. …

Adaptive Management In Native Grasslands Managed By The U.S. Fish And Wildlife Service—Implications For Grassland Birds, Lawrence D. Igl, Welsey E. Newton, Todd A. Grant, Cami S. Dixon

United States Geological Survey: Publications

Burning and grazing are natural processes in native prairies that also serve as important tools in grassland management to conserve plant diversity, to limit encroachment of woody and invasive plants, and to maintain or improve prairies. Native prairies managed by the U.S. Fish and Wildlife Service (FWS) in the Prairie Pothole Region of the northern Great Plains have been extensively invaded by nonnative, cool-season species of grasses. These invasions were believed to reflect a common management history of long-term rest and little or no defoliation by natural processes (burning and grazing). To address the challenges associated with these invasive species, …

Assessing The Feasibility Of Soil Infiltration Trenches For Highway Runoff Control On The Island Of Oahu, Hawaii, Martina Sobotkova, Jaromir Dusek, Ghasem Alavi, Laxman Sharma, Chittaranjan Ray

Nebraska Water Center: Faculty Publications

The coastal waters of Hawaii are extremely important for recreation as well as for the health of the marine environment. Non-point source pollution from storm runoff poses a great threat to surface water quality in Hawaii. The State of Hawaii Department of Transportation (HDOT) includes infiltration trenches as a best management practice (BMP) option to reduce pollution caused by stormwater runoff. HDOT guidelines state that the implementation of BMPs is needed to reduce sediment and pollutant loads to streams and the ocean. In this study, the suitability of soils adjacent to highways on Oahu for the siting of infiltration trenches …

Motivations, Specializations, Identities, And Constraints Associated With Hunting In Nebraska, Alisha Grams

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

No abstract provided.

The Impact Of Sensor Response And Airspeed On The Representation Of The Convective Boundary Layer And Airmass Boundaries By Small Unmanned Aircraft Systems, Adam L. Houston, Jason M. Keeler

Department of Earth and Atmospheric Sciences: Faculty Publications

The objective of the research presented is to assess the impact of sensor response and aircraft airspeed on the accuracy of in situ observations collected by small unmanned aircraft systems profiling the convective boundary layer or transecting airmass boundaries. Estimates are made using simulated aircraft flown within large-eddy simulations. Both instantaneous errors (differences between observed temperature, which include the effects of sensor response and airspeed, and actual temperature) and errors in representation (differences between serial observations and representative snapshots of the atmospheric state) are considered. Synthetic data are retrieved assuming a well-aspirated first-order sensor mounted on rotary-wing aircraft operated as …

Lake Regionalization And Diatom Metacommunity Structuring In Tropical South America, Xavier Benito, Sherilyn C. Fritz, Miriam Steinitz-Kannan, Maria I. Velez, Michael M. Mcglue

Department of Earth and Atmospheric Sciences: Faculty Publications

Lakes and their topological distribution across Earth’s surface impose ecological and evolutionary constraints on aquatic metacommunities. In this study, we group similar lake ecosystems as metacommunity units influencing diatom community structure. We assembled a database of 195 lakes from the tropical Andes and adjacent lowlands (8°N–30°S and 58–79°W) with associated environmental predictors to examine diatom metacommunity patterns at two different levels: taxon and functional (deconstructed species matrix by ecological guilds). We also derived spatial variables that inherently assessed the relative role of dispersal. Using complementary multivariate statistical techniques (principal component analysis, cluster analysis, nonmetric multidimensional scaling, Procrustes, variance partitioning), we …

Sheeting Joints And Polygonal Patterns In The Navajo Sandstone, Southern Utah: Controlled By Rock Fabric, Tectonic Joints, Buckling, And Gullying, David B. Loope, Caroline M. Burberry

Department of Earth and Atmospheric Sciences: Faculty Publications

Sheeting joints are ubiquitous in outcrops of the Navajo Sandstone on the west-central Colorado Plateau, USA. As in granitic terrains, these are opening- mode fractures and form parallel to land surfaces. In our study areas in south-central Utah, liquefaction during Jurassic seismic events destroyed stratification in large volumes of eolian sediment, and first-order sheeting joints are now preferentially forming in these structureless (isotropic) sandstones. Vertical cross-joints abut the land-surface-parallel sheeting joints, segmenting broad (tens of meters) rock sheets into equant, polygonal slabs ~5 m wide and 0.25 m thick. On steeper slopes, exposed polygonal slabs have domed surfaces; eroded slabs …

Cosmic-Ray Neutron Probes On The High Plains Of Nebraska: Applications To Large Scale Agriculture, Trenton E. Franz, Darin Desilets, Ammar Wahbi

Department of Earth and Atmospheric Sciences: Faculty Publications

Cosmic-rays have some surprising applications in precision agriculture. The cosmic-ray neutron probe (CRNP), when implemented as a roving instrument, can be used to create spatial maps of soil moisture, and from these maps soil hydraulic properties can be inferred. In this work, we combine data from a mobile CRNP with laboratory samples to make spatial predictions of soil hydraulic properties for select field sites around the state of Nebraska. These maps, which focus on wilting point and field capacity, can, in turn, be used to determine the optimal timing and application rates for irrigation farmers, many of whom have the …

Exotic Invasive Pomacea Maculata (Giant Apple Snail) Will Depredate Eggs Of Frog And Toad Species Of The Southeastern Us, Jacoby Carter, Darren Johnson, Sergio Merino

United States Geological Survey: Staff Publications

Pomacea maculata (Giant Apple Snail) is a freshwater snail from South America that is an invasive species on the Gulf of Mexico coastal plain. A sister species has been shown to prey on amphibian eggs in Asia. To test whether the Giant Apple Snail will prey on amphibian eggs, we presented eggs of Lithobates palustris (Pickerel Frog), Lithobates pipiens (Northern Leopard Frog), and Anaxyrus americanus (American Toad) to Giant Apple Snails in a laboratory experiment. Giant Apple Snails ate the eggs of all 3 species.

Evaluating Restored Tidal Freshwater Wetlands, Andrew H. Baldwin, Richard S. Hammerschlag, Donald R. Cahoon

United States Geological Survey: Staff Publications

Tidal freshwater wetlands are recognized as highly productive coastal wetlands that support diverse assemblages of plants and animals and complex biogeochemical cycles (in this book, see Chapter 18 by Whigham et al. and Chapter 19 by Megonigal and Neubauer). Many tidal freshwater wetlands and their associated ecosystem services have been damaged or destroyed by urbanization, agriculture, and other human activities (Baldwin, 2004; Barendregt et al., 2006). Increasing recognition of the value of remaining wetlands and environmental regulations requiring wetland mitigation (i.e., enhancement, creation, or restoration of wetlands to compensate for wetland losses; Kentula, 2000) has driven the restoration of all …

Evaluating The Waterfowl Breeding Population And Habitat Survey For Scaup, Michael L. Schummer, Alan D. Afton, Shannon S. Badzinski, Scott A. Petrie, Glenn H. Olsen, Mark A. Mitchell

United States Geological Survey: Staff Publications

Potential bias in breeding population estimates of certain duck species from the Waterfowl Breeding Population and Habitat Survey (WBPHS) has been a concern for decades. The WBPHS does not differentiate between lesser (Aythya affinis) and greater (A. marila) scaup, but lesser scaup comprise 89% of the combined scaup population and their population estimates are suspected to be biased. We marked female lesser scaup (i.e., marked scaup) in the Mississippi and Atlantic Flyways, Canada and United States, with implantable satellite transmitters to track their spring migration through the traditional and eastern survey areas of the WBPHS, 2005–2010. Our goal was to …

Risks And Hazards Of Rodenticide To Non-Raptor Birds, Nimish B. Vyas

United States Geological Survey: Staff Publications

Incident data can support risk assessments by providing evidence of adverse effects of rodenticides to birds following operational applications. Traditionally, field monitoring for rodenticide incidents has focused primarily on raptors. However, nonraptor birds may also be poisoned (rodenticide exposure resulting in adverse effects including mortality) by rodenticides through consumption of the rodenticide bait and contaminated prey. I conducted a literature search canvassing 12 government and scholarly databases for rodenticide incidents (evidence of exposure to a rodenticide, adverse effects, or exposure to placebo baits) involving non-raptor birds. I used the search terms ‘rodenticide’ and ‘birds’ and from these results, I excluded …

Vegetation Responses To Sagebrush-Reduction Treatments Measured By Satellites, Aaron N. Johnston, Erik A. Beever, Jerod A. Merkle, Geneva Chong

United States Geological Survey: Staff Publications

Time series of vegetative indices derived from satellite imagery constitute tools to measure ecological effects of natural and management-induced disturbances to ecosystems. Over the past century, sagebrush-reduction treatments have been applied widely throughout western North America to increase herbaceous vegetation for livestock and wildlife. We used indices from satellite imagery to 1) quantify effects of prescribed-fire, herbicide, and mechanical treatments on vegetative cover, productivity, and phenology, and 2) describe how vegetation changed over time following these treatments. We hypothesized that treatments would increase herbaceous cover and accordingly shift phenologies towards those typical of grass-dominated systems. We expected prescribed burns would …

Evaluating Restored Tidal Freshwater Wetlands, Andrew H. Baldwin1,, Richard S. Hammerschlag, Donald R. Cahoon

United States Geological Survey: Staff Publications

Tidal freshwater wetlands are recognized as highly productive coastal wetlands that support diverse assemblages of plants and animals and complex biogeochemical cycles (in this book, see Chapter 18 by Whigham et al. and Chapter 19 by Megonigal and Neubauer). Many tidal freshwater wetlands and their associated ecosystem services have been damaged or destroyed by urbanization, agriculture, and other human activities (Baldwin, 2004; Barendregt et al., 2006). Increasing recognition of the value of remaining wetlands and environmental regulations requiring wetland mitigation (i.e., enhancement, creation, or restoration of wetlands to compensate for wetland losses; Kentula, 2000) has driven the restoration of all …

The Global Food-Energy-Water Nexus, Paolo D’Odorico, Kyle Frankel Davis, Lorenzo Rosa, Joel A. Carr, Davide Chiarelli, Jampel Dell’Angelo, Jessica Gephart, Graham K. Macdonald, David A. Seekell, Samir Suweis, Maria Cristina Rulli

United States Geological Survey: Staff Publications

Water availability is a major factor constraining humanity’s ability to meet the future food and energy needs of a growing and increasingly affluent human population. Water plays an important role in the production of energy, including renewable energy sources and the extraction of unconventional fossil fuels that are expected to become important players in future energy security. The emergent competition for water between the food and energy systems is increasingly recognized in the concept of the “food-energy-water nexus.” The nexus between food and water is made even more complex by the globalization of agriculture and rapid growth in food trade, …

Evaluating The Waterfowl Breeding Population And Habitat Survey For Scaup, Michael L. Schummer, Alan D. Afton, Shannon S. Badzinski, Scott A. Petrie, Glenn H. Olsen, Mark A. Mitchell

United States Geological Survey: Staff Publications

Potential bias in breeding population estimates of certain duck species from the Waterfowl Breeding Population and Habitat Survey (WBPHS) has been a concern for decades. The WBPHS does not differentiate between lesser (Aythya affinis) and greater (A. marila) scaup, but lesser scaup comprise 89% of the combined scaup population and their population estimates are suspected to be biased. We marked female lesser scaup (i.e., marked scaup) in the Mississippi and Atlantic Flyways, Canada and United States, with implantable satellite transmitters to track their spring migration through the traditional and eastern survey areas of the WBPHS, 2005–2010. Our goal was to …

Is Sensitivity To Anticoagulant Rodenticides Affected By Repeated Exposure In Hawks?, Barnett A. Rattner, Rebecca S. Lazarus, Thomas G. Bean, Katherine E. Horak,, Steven F. Volker, Julia Lankton

United States Geological Survey: Staff Publications

A seminal question in wildlife toxicology is whether exposure to an environmental contaminant, in particular a secondgeneration anticoagulant rodenticide, can evoke subtle long lasting effects on body condition, physiological function and survival. Many reports indicate that non-target predators often carry residues of several rodenticides, which is indicative of multiple exposures. An often-cited study in laboratory rats demonstrated that exposure to the second-generation anticoagulant rodenticide brodifacoum prolongs blood clotting time for a few days, but weeks later when rats were re-exposed to the first-generation anticoagulant rodenticide warfarin, coagulopathy was more pronounced in brodifacoum-treated rats than naïve rats exposed to warfarin. To …

Recent Ecological Change In Ancient Lakes, Stephanie E. Hampton, Suzanne Mcgowan, Ted Ozersky, Salvatore G. P. Virdis, Tuong Thuy Vu, Trisha L. Spanbauer, Benjamin M. Kraemer, George Swann, Anson W. Mackay, Stephen M. Powers, Michael F. Meyer, Stephanie G. Labou, Catherine M. O'Reilly, Morgan Dicarlo, Aaron W. E. Galloway, Sherilyn C. Fritz

Department of Earth and Atmospheric Sciences: Faculty Publications

Ancient lakes are among the best archivists of past environmental change, having experienced more than one full glacial cycle, a wide range of climatic conditions, tectonic events, and long association with human settlements. These lakes not only record long histories of environmental variation and human activity in their sediments, but also harbor very high levels of biodiversity and endemism. Yet, ancient lakes are faced with a familiar suite of anthropogenic threats, which may degrade the unusual properties that make them especially valuable to science and society. In all ancient lakes for which data exist, significant warming of surface waters has …

Ensemble Sensitivity Analysis For Targeted Observations Of Supercell Thunderstorms, George L. Limpert, Adam L. Houston

Department of Earth and Atmospheric Sciences: Faculty Publications

Ensemble sensitivity analysis (ESA) has been demonstrated for observation targeting of synoptic-scale and mesoscale phenomena, but could have similar applications for storm-scale observations with mobile platforms. This paper demonstrates storm-scale ESA using an idealized supercell simulated with a 101-member CM1 ensemble. Correlation coefficients are used as a measure of sensitivity and are derived from single-variable and multivariable linear regressions of pressure, temperature, humidity, and wind with forecast response variables intended as proxies for the strength of supercells. This approach is suitable for targeting observing platforms that simultaneously measure multiple base-state variables. Although the individual correlations are found to be noisy …

An Observational And Modeling Study Of Mesoscale Air Masses With High Theta-E, Wolfgang Hanft, Adam L. Houston

Department of Earth and Atmospheric Sciences: Faculty Publications

Typically, the cool side of an airmass boundary is stable to vertical motions due to its associated negative buoyancy. However, under certain conditions, the air on the cool side of the boundary can undergo a transition wherein it assumes an equivalent potential temperature and surface-based convective available potential energy that are higher than those of the air mass on the warm side of the boundary. The resultant air mass is herein referred to as a mesoscale air mass with high theta-e (MAHTE). Results are presented from an observational and mesoscale modeling study designed to examine MAHTE characteristics and the processes …