NU Water-Related Research in the Middle Niobrara NRD

The list below shows water-related research being conducted within your NRD or that affects your NRD. They are sorted by water topic, then by primary contact's last name.

Displaying 17 records found for Middle Niobrara NRD


Topic
Project's Primary Contact Information
Name van Donk, Simon
Unit West Central Research and Extension Center
Email simon.vandonk@unl.edu
Phone 308-696-6709
Web Page http://westcentral.unl.edu/web/westcentral/svandonk
Project Information
Title Site-specific management of heterogeneous fields
Other(s) Richard Ferguson, Department of Agronomy & Horticulture, rferguson1@unl.edu; Tim Shaver, West Central Research & Extension Center, tim.shaver@unl.edu 
Description

Variable rate technology (e.g., for irrigation, fertilization, seeding) has developed rapidly, enabling agricultural producers to practice site-specific management on heterogeneous fields. However, knowledge is lacking on how to implement site-specific management; the variable rate technology is available to producers, but knowledge is needed on where, when, and how much water and/or nutrients to apply. A research project was started in 2011, studying the interactions of landscape position (topography), soil type, irrigation and nitrogen.

Impact:Producers will be able to better implement site-specific management on heterogeneous fields benefitting their economic bottom line as well as the environment.

Project Support John Deere
Project Website
Report
Current Status Continuing
Topic Climate
Project's Primary Contact Information
Name Shulski, Martha
Unit High Plains Regional Climate Center
Email mshulski3@unl.edu
Phone 402-472-6711
Web Page http://snr.unl.edu/aboutus/who/people/faculty-member.asp?pid=474
Project Information
Title High Plains Regional Climate Center - Monitoring Stations
Description

As the demand for water grows, it is important to have reliable information for various assessments, such as drought, fire, and water development. In an effort to understand the surface hydrology and the water and energy interactions at the surface, scientists with the High Plains Regional Climate Center have installed a series of monitoring stations that collect temperature, humidity, solar radiation, windspeed and direction, soil temperature, precipitation and soil moisture data. These stations take hourly and daily data which can be used to calculate evapotranspiration and water balance terms. Monitoring equipment is located near Higgins Ranch, Sparks, Merritt, Ainsworth, New Port, Barta, Gudmundsens, Halsey, and Merna.

Volunteers supplement these stations by using rain gauges to monitor precipitation; volunteers enter their data online as part of the Nebraska Rainfall Assessment and Information Network (NeRAIN). In total volunteers from 40 states contribute precipitation data to the Community Collaborative Rain, Hail and Snow Network (CoCoRaHS). The CoCoRaHS network has been incorporated into the Applied Climate Information System (ACIS), which allows resource managers, researchers, and decision-makers to better access data.

Project Support National Climatic Data Center
Project Website http://hprcc.unl.edu
Report
Current Status Continuing
Topic Extension
Project's Primary Contact Information
Name Melvin, Steve
Unit West Central Research and Extension Center
Email smelvin1@unl.edu
Phone 308-367-4424
Web Page http://www.frontier.unl.edu/
Project Information
Title Irrigation Strategies Field Tour Series
Other(s) Bill Kranz, Northeast Research and Extension Center, wkranz1@unl.edu; Charles Shapiro, Northeast Research and Extension Center, cshapiro1@unl.edu; Simon Van Donk, West Central Research and Extension Center, svandonk2@unl.edu; Derrel Martin, Biological Systems Engineering, dmartin1@unl.edu 
Description

The 2009 Irrigation Strategies Field Tour Series will focus on showing farmers and crop consultants management strategies to conserve water.

The tour topics, which vary by location, include: Water Resource Update; Comparing Irrigation Energy Sources: Costs and Emissions Requirements; Monitoring Crop Water Use and Soil Moisture Status - Simple, Durable, Accurate, and Economical Tools; Water Savings with Crop Residue Management; How the Amount of Water and Nitrogen Applied with a Center Pivot Affects Crop Yield; How to Get the Most from Your Nitrogen Dollar; Where Slow Release Nitrogen Fertilization Fits into Corn Production; Variable Rate Irrigation Equipment for Center Pivots; Predicting the Last Irrigation; and How Time of Application and Amount of Water Applied Affects Crop Yield.

In 2008 eleven field demonstrations, with thirteen field tours at the sites, were conducted around the state to teach irrigation options specifically adapted for Nebraska crops, soils, and irrigation issues. No-till water savings were shown at the Curtis site and at the Ainsworth site, and a demonstration showed producers how nitrogen losses due to drainage taking soluble nitrogen below the root zone can be prevented with correct water application.

The farmers participating in 2008 reported managing an average of 1,067 acres of irrigated cropland per farm. The average reported value of the knowledge gained by the producers completing the survey was $22,215 per operation. If this average was extended to all of the 160 producers attending, the value of the education gained would be more than $3.55 million per year. The reported potential water savings of 2.2 acre-inches/acre by the farmers would be a 15-20% savings from the typical irrigation water usage and if extended to the average farm size, would be more than 31,300 acre-feet/year. The other 40 people attending the tours also reported substantial knowledge gains that will help save water and increase returns per acre. Their occupations ranged from crop consultants, agri-business representatives, government agency personnel, etc. The acre influence/manage ranged from none to over 100,000 acres. This variation makes it difficult to determine the impact of their involvement, but it is very significant as well. For example, just the eight people that listed the acres they manage/influence (38,875 acres on average) and the value of the knowledge gained ($18.78/acre on average) would result in over $5.84 million per year.

Nine of the eleven irrigation demonstration sites were in farmer fields in 2008, and two were located on the NCTA farm. The plot locations included sites near Alma, Gothenburg, Axtell, Edison, Loomis, Ainsworth, Imperial, Benkelman, Upland, and Curtis (two sites). Two sites (Curtis and Loomis) had line-source sprinkler systems installed to demonstrate irrigation strategies for corn. All sites had soil-moisture-monitoring equipment and ET gauges installed for use at the field tours and to allow the producers and crop consultants to work with the equipment. The Ainsworth site demonstrated the relationship between varying amounts of nitrogen on irrigated corn. The data generated from the sites will also be used for Extension programs in the future.

Project Support U.S. Department of Interior - Bureau of Reclamation
Project Website http://water.unl.edu/irrigationtournews
Report
Current Status Continuing
Topic Hydrology
Project's Primary Contact Information
Name Ayers, Jerry
Unit School of Natural Resources
Email jayers1@unl.edu
Phone 402-472-0996
Web Page http://snr.unl.edu/aboutus/who/people/faculty-member.asp?pid=5
Project Information
Title Box Butte County / Niobrara River Numerical Groundwater Flow Model Studies
Description

The main objective of these studies was to determine the effect, if any, of large-scale regional pumping on the base flow of the Niobrara River. One study involved the construction and implementation of a groundwater-flow model for Box Butte County and the surrounding region to simulate hydrogeologic and hydraulic conditions, including groundwater extraction by large-capacity wells. The other study focused on the upper reaches of the Niobrara River to obtain estimates of stream-bed hydraulic conductivity (i.e., the ease with which water can move through pore spaces or fractures in the stream-bed) to be used as input to the modeling effort.

The groundwater-flow model was calibrated to predevelopment by primarily adjusting recharge flux through a trial-and-error process until a reasonable fit was obtained to the observed water table configuration of 1938. Once calibrated to predevelopment heads, transient simulations (i.e., simulations taking into account real-life conditions, thus modeling potential real-life changes in the basin), were run to model the change in heads due to pumping for the time period between 1938 and 2005. Results from these simulations were compared with observed heads for available years. After satisfactory results were obtained from the transient simulations, two additional scenarios were tested. These were simulations where all wells were turned off and where only those wells in Box Butte County and its proximity were active. The computer program ZONEBUDGET, which computes the water budget for user-defined zones, was run coincident with all simulations. Both head and water budget computation results were then used to determine the effect of pumping on the base flow the Niobrara River.

Based on model results, reductions in the base flow of the Niobrara River is due primarily to localized pumping effects, rather than from groundwater extraction on a regional scale. A comparison of simulated outflow values for selected reaches of the Niobrara River indicates that 1) flow characteristics in the uppermost part of the basin did not change greatly over the period of pumping indicating that base flow is not significantly reduced by large-scale pumping, 2) significant changes in base flow appear to have occurred after about 1960 in the middle and lower reaches, 3) the maximum change in flow for the middle reach due to all wells pumping is 19.6% and only 4.4% for Box Butte wells, with both maximum reductions occurring at the end of the 2005 pumping season, 4) the maximum change in flow for the lower reach is about 24.4% for all wells and only 2.5% for Box Butte wells, again, both occur at the end of the 2005 pumping season. Overall, the Niobrara River appears to be a gaining stream along most of its flow path, with the exception of the uppermost part of the basin.

The conclusion is that the affects of large-scale regional pumping appears to not impact base flow in the Niobrara River to any significant degree. Rather, localized pumping, especially where irrigation wells are situated near the river, reduces base flow on the order of 20% to 25%. For the most part, the Niobrara River valley is somewhat isolated from the extensive pumping taking place in Box Butte County. The upper reach is sufficiently distant from the pumping center that the cone of depression has little effect on the water table. Much of the middle reach transects units of the White River group that are considered to be nearly impermeable, and thus, provide a hydrogeologic barrier, preventing the northward expansion of the cone of depression. Pumping along the lower reach of the Niobrara River has a much greater influence on base flow reduction simply due to the proximity of the extraction wells to the river.

Project Support Nebraska Department of Natural Resources
Project Website http://www.dnr.state.ne.us/Publications_Studies/Box-Butte_ModelProjectCompletionReport.pdf
Report
Current Status Completed
Topic Hydrology
Project's Primary Contact Information
Name Lenters, John
Unit School of Natural Resources
Email jlenters2@unl.edu
Phone 402-472-9044
Web Page http://snr.unl.edu/aboutus/who/people/faculty-member.asp?pid=743
Project Information
Title On Basin Residence Time and Annual Hydrology: Development of Annual Hydrology Model of the Sandhills Rivers
Other(s) Erkan Istanbulluoglu, University of Washington, erkani@u.washington.edu; Durelle Scott, Virginia Tech, dscott@vt.edu; Tiejun Wang, University of Washington-Seattle, tjwang@u.washington.edu 
Description

Simple models of annual and mean annual basin runoff and evapotranspration, such as the one proposed by Budyko, are useful for investigating the relationship between river flow and climate, and planning water storage structures in basins where long term streamflow measurements are not available. Such models are often based on the assumption that annual precipitation is in balance with annual runoff and evapotranspiration, and change in water storage of the basin is negligible. In basins where groundwater is the dominant source of streamflow this assumption hardly holds.

In this study first we develop a technique to investigate groundwater residence time to identify time scales over which a simple model of mean annual runoff can be meaningfully used. The model is applied in the Niobrara and Loup Rivers. Second we develop an annual hydrology model by solving the rate of change in basin storage. The runoff component of the model is based on the well-known linear reservoir model and a parameterization to characterize runoff on saturated areas. River water storages and streamflow diverted for irrigation are included as inputs in the model. The model explained as high as 80% of the annual variability of runoff in the Niobrara River at the Sparks gage. The model underscores the importance of saturation overland flow in the basin. Finally we used the model to investigate climate change scenarios, including extreme dry and wet conditions, as well as scenarios for the Medieval Warm Period during which Sandhills were destabilized as suggested by geological evidence.

Project presentation at the 2008 Water Colloquium

Project Support National Science Foundation
Project Website
Report Lenters_Groundwater.pdf
Current Status Published "On the role of groundwater and soil texture in the regional water balance: An investigation of the Nebraska Sand Hills", USA, Water Resour. Res., 45, W10413, doi:10.1029/2009WR007733.
Topic Hydrology
Project's Primary Contact Information
Name Pederson, Darryll
Unit Earth and Atmospheric Sciences
Email dpederson2@unl.edu
Phone 402-472-7563
Web Page http://eas.unl.edu/people/faculty_page.php?lastname=Pederson&firstname=Darryll&type=REG
Project Information
Title Waterfalls on the Niobrara River's Spring-fed Tributaries
Description The waterfalls on the spring-fed tributaries of the Niobrara River downstream from Valentine, Nebraska are unique in that the waterfalls are convex downstream. Groundwater discharge on either side of the waterfalls has led to significant weathering because of freeze/thaw cycles in the winter and wet/dry cycles in the summer. The water falling over the face of the falls protects them from the two weathering processes. Because the weathering rates on either side are higher than the erosion rates from falling water, the face of the falls is convex downstream. Similar waterfall face morphology occurs on the Island of Kauai where the main weathering processes are driven by vegetation and the presence of water.
Project Support National Park Service through the Great Plains Cooperative Ecosystem Studies Unit
Project Website http://snr.unl.edu/gpcesu/Project_library.htm
Report Waterfalls_Abstract.pdf
Current Status Completed
Topic Hydrology
Project's Primary Contact Information
Name Wang, Tiejun
Unit School of Natural Resources
Email tiejunwang215@yahoo.com
Phone
Web Page http://snr.unl.edu/aboutus/who/people/faculty-member.asp?pid=945
Project Information
Title Niobrara River Flow Variability
Other(s) Erkan Istanbulluoglu, University of Washington, erkani@u.washington.edu 
Description This project develops a database for hydrological and climatological variables within the Niobrara River basin so that researchers may study flow variability in the Niobrara River and its historical changes. Analysis includes all existing and discontinued streamflow gages within the system. Surface water diversion data are also collected to relate to changes in the flow discharge. Annual water yield of the river is studied at Sparks and Verdel gages. A lumped annual water yield model is developed to identify the natural variables that control runoff. The model uses annual runoff as forcing variable, as well as water diversions as outflux from the system. The model is currently being extended to monthly time scales.
Project Support Nebraska Game and Parks Commission, National Park Service
Project Website
Report
Current Status Underway
Topic Recreation
Project's Primary Contact Information
Name Laing, Kim (Graduate Student)
Unit School of Natural Resources
Email kmeuhe1@unl.edu
Phone n/a
Web Page
Project Information
Title Assess Extent of Disturbance by Canoeists in Tributaries to the Niobrara National Scenic River
Other(s) Kyle Hoagland, School of Natural Resources, khoagland1@unl.edu 
Description

The Niobrara is a rich and unique ecosystem. Because it is relatively swift and shallow along this reach, the Niobrara is also a popular locale for tens of thousands of canoeists each year. Frequent bottom trampling and bank destabilization can result in a variety of short and long-term changes, including bottom substrate degradation, higher levels of drift including premature drift of aquatic larvae, increased turbidity and sedimentation, and the elimination of sensitive species.

The overall goal of this project is to assess the extent of disturbance by canoeists in tributaries to the Niobrara National Scenic River and its overall impact on stream ecosystem health. This assessment will be used to evaluate resource management practices in these unique habitats, while also serving as a basis for future comparisons to assess habitat degradation.

Ten tributaries, located along the south side of the Niobrara River, were sampled each month May through September. The tributaries were divided into five streams that were potentially impacted from visitors, located upstream, and five streams that were known to have no visitors. A mini-surber sampler was used to collect invertebrates from upstream sections of the tributaries (above the waterfalls with no visitors) and from downstream sections, below the waterfalls. Current velocity, depth, width, and distance from the edge of the tributary were recorded at each location. Water temperature, pH and conductivity were measured and a water sample taken to measure total nitrogen, total phosphorus and turbidity. In June, July and August visitor information was collected by volunteers at each potentially impacted tributary. Each volunteer counted the number of times the tributary was disturbed. This information, along with daily visitor use collected by Fort Niobrara, U.S. Fish and Wildlife Service, was used to calculate the amount of disturbance occurring at each location.

Project Support n/a
Project Website
Report
Current Status Completed
Topic Recreation
Project's Primary Contact Information
Name Shultz, Steve
Unit UNO Real Estate Research Center
Email sshultz@mail.unomaha.edu
Phone 402-554-2810
Web Page http://cba.unomaha.edu/dir/HomePageBio.cfm?id=347
Project Information
Title Economic and Social Values of Recreation on the Niobrara National Scenic River
Description

The goal of this project is to generate objective and accurate economic data and analyses that will allow the State of Nebraska to evaluate an in-stream appropriation on the Niobrara River for recreation purposes. Nebraska in-stream flow laws and regulations as stated in statute 46-2,116 specify that an in-stream appropriation must be in the public interest on the basis of:

  • The econmic, social, and environmental value of the in-stream use or uses including, but not limited to, recreation, fish and wildlife, induced recharge for municipal water systems, and water quality maintenance; and
  • The economic, social, and environmental value of reasonably foreseeable alternative out-of-stream uses of water that will be foregone or accorded junior status if the appropriation is granted.

The economic value of in-stream uses for recreation will involve estimates of both direct expenditures by river recreationists and the value of their use of the Niobrara Scenic River for boating and tubing using a travel cost model. The economic value of reasonably forseeable alternative out-of-stream uses will be determined by estimating the change in economic value of irrigation in the Niobrara River watershed based upon agricultural land sales from 2000 to 2007. The societal values associated with in-stream flows of and recreation on the Niobrara River will also be calculated using a telephone survey.

Project presentation at the 2008 Water Colloquium

Project Support Nebraska Game and Parks Commission
Project Website
Report Niobrara_Values.pdf
Current Status Completed
Topic Sandhills Studies and Modeling
Project's Primary Contact Information
Name Billesbach, Dave
Unit Biological Systems Engineering
Email dbillesbach1@unl.edu
Phone 402-472-7961
Web Page http://bse.unl.edu/faculty/Billesbach.shtml
Project Information
Title Effects of Precipitation and Groundwater on Grassland Productivity in the Nebraska Sand Hills
Other(s) Tim Arkebauer, Agronomy and Horticulture, tarkebauer1@unl.edu 
Description

In the Sand Hills the depth to groundwater greatly affects the types and amounts of grasses that grow there, suggesting a strong linkage between groundwater, precipitation, and grass productivity. Wet meadows are where the water rable is usually less than a meter below the surface and make up about 10% of the Sand Hills land area. Dry valleys are where the water table never intersects the land surface and usually lies several meters below; dry valleys also make up about 10% of the Sand Hills land area. Except for lakes and wetlands (about 2% of the land area), the rest of the Sand Hills is dunal uplands where the water table is many meters below the surface.

It has long been assumed that the Sand Hills are a recharge zone for the underlying aquifer and that local precipitation more than accounts for the water usage of surface vegetation. This research measures how much water enters the Sand Hills ecosystem (via precipitation) and how much water leaves the land surface - the Sand Hills surface water balance. Research shows that Sand Hills surface water is lost primarily through evapotranspiration, or surface water evaporation and plant transpiration, with the relative size of each varying greatly depending on the time of year and other factors, such as drought. Research also shows that: 1) the most water is transferred to the atmosphere from wet meadows, followed by dry valleys and dunal uplands; 2) the close proximity to the aquifer acts as a buffer to both wet meadows and dry valleys, but not to dunal uplands; and 3) groundwater buffering is most affected by regional rather than local precipitation events. The long-term goal of this project is to study and better understand the relationship between water and the vegetative land cover (carbon).

Project Support n/a
Project Website
Report Billesbach_SandHills_Water.pdf
Current Status Continuing
Topic Sandhills Studies and Modeling
Project's Primary Contact Information
Name Efting, Aris
Unit School of Natural Resources
Email aefting@unl.edu
Phone 402-472-3471
Web Page http://snr.unl.edu/aboutus/who/people/faculty-member.asp?pid=226
Project Information
Title Determining Toxic Algal Bloom Frequency in Nebraska Lakes
Description Research has been conducted in the Sandhills to determine whether or not there has been an increase in toxic algal blooms. Four different lakes were cored to identify the lakes' history of toxic algal blooms and determine whether there is an increase in toxin concentrations post 1950.
Project Support Layman Fund
Project Website
Report
Current Status Underway
Topic Sandhills Studies and Modeling
Project's Primary Contact Information
Name Hu, Qi (Steve)
Unit School of Natural Resources
Email qhu2@unl.edu
Phone 402-472-6642
Web Page http://snr.unl.edu/aboutus/who/people/faculty-member.asp?pid=54
Project Information
Title The Missing Term in Surface Water Balance in the Great Plains
Other(s) Jinsheng You, School of Natural Resources, jyou2@unl.edu 
Description

It has been recognized that the surface water budget derived from the NCEP-NCAR Reanalysis and other existing climatic datasets is not in balance in the Great Plains region. This imbalance is shown by large surface evaporation which cannot be supported by source terms in the budget equation. This large surface evaporation is always appearing in calculations from the surface and soil moisture conditions specified in those datasets. This imbalance poses serious uncertainties to diagnostic and modeling studies of energy and carbon balances and to our understanding of atmospheric/climatic processes in this region. An effort aiming at identifying sources causing the water budget imbalance has been underway and some preliminary results have been obtained. A main source of the imbalance arises from the calculation of the surface evaporation. It was found that the surface and soil water specified in those datasets (developed from integrations of both observations and model simulations) is biased because of inaccurate descriptions of the soil properties, particularly the sandy soils in the Nebraska Sand Hills. A revised model with more accurate descriptions of the soils and soil hydrology in the Sand Hills has produced a balance surface water budget in the Sand Hills.

Project presentation at the 2008 Water Colloquium

Project Support Department of Commerce - National Oceanic and Atmospheric Administration (NOAA)
Project Website
Report
Current Status
Topic Sandhills Studies and Modeling
Project's Primary Contact Information
Name Hubbard, Kenneth
Unit High Plains Regional Climate Center
Email khubbard1@unl.edu
Phone 402-472-8294
Web Page http://snr.unl.edu/aboutus/who/people/faculty-member.asp?pid=55
Project Information
Title Assessment of Soil Moisture Dynamics of the Nebraska Sandhills Using Long-Term Measurements and a Hydrology Model
Other(s) Venkataramana Sridhar; David Wedin, School of Natural Resources, dwedin1@unl.edu 
Description Soil moisture, evapotranspiration, and other major water balance components were investigated for six Nebraska Sandhills locations during a 6 year period (1998-2004) using a hydrological model. Annual precipitation in the study period ranged from 330 to 580 mm. Soil moisture was measured continuously at 10, 25, 50, and 100 cm depth at each site. Model estimates of surface (0-30 cm), subsurface (30-91 cm), and root zone (0-122 cm) soil moisture were generally well correlated with observed soil moisture. The correlations were poorest for the surface layer, where soil moisture values fluctuated sharply, and best for the root zone as a whole. Modeled annual estimates of evapotranspiration and drainage beneath the rooting zone showed large differences between sites and between years. Despite the Sandhills' relatively homogeneous vegetation and soils, the high spatiotemporal variability of major water balance components suggest an active interaction among various hydrological processes in response to precipitation in this semiarid region.
Project Support National Science Foundation, High Plains Regional Climate Center
Project Website
Report Hubbard06.pdf
Current Status Published in Journal of Irrigation and Drainage Engineering, September/October 2006, 463-473
Topic Sandhills Studies and Modeling
Project's Primary Contact Information
Name Loope, David
Unit Earth and Atmospheric Sciences
Email dloope1@unl.edu
Phone 402-472-2647
Web Page http://eas.unl.edu/people/faculty_page.php?lastname=Loope&firstname=David&type=REG
Project Information
Title Large Wind Shift on the Great Plains During the Medieval Warm Period
Other(s) Venkataramana Sridhar; James Swinehart, School of Natural Resources, jswinehart1@unl.edu; Joseph Mason, University of Wisconsin, Madison, mason@geography.wisc.edu; Robert Oglesby, School of Natural Resources, roglesby2@unl.edu; Clinton Rowe, Geosciences, crowe1@unl.edu 
Description Spring-Summer winds from the south move moist air from the Gulf of Mexico to the Great Plains. Growing season rainfall sustains prairie grasses that keep large dunes in the Nebraska Sandhills immobile. Longitudinal dunes built during the Medieval Warm Period (800-100 yBP) record the last major period of sand mobility. These dunes are oriented NW-SE and are composed of cross-strata with bi-polar dip directions. The trend and structure of these dunes directly record a prolonged drought that was initiated and sustained by a historically unprecedented shift of Spring-Summer atmospheric circulation over the Plains: southerly flow of moist air was replaced by dry southwesterly flow.
Project Support National Science Foundation
Project Website
Report Loope Wind Shift.pdf
Current Status Published in Science November 2007 318:1284-1286
Topic Sandhills Studies and Modeling
Project's Primary Contact Information
Name Wedin, Dave
Unit School of Natural Resources
Email dwedin1@unl.edu
Phone 402-472-9608
Web Page http://snr.unl.edu/aboutus/who/people/faculty-member.asp?pid=128
Project Information
Title Sand Hills Biocomplexity Project
Other(s) Vitaly Zlotnik, Department of Geosciences, vzlotnik1@unl.edu. 
Description

The Sand Hills, the largest sand dune area in the Western Hemisphere, is now stabalized by native grasses. This was not always the case. The Sand Hills have mobilized several times over the last 10,550 years. Major droughts destabilized significant portions of the Sand Hills as recently as 1000 years ago. The stability of the Sand Hills affects not only hundreds of cattle ranches, but also the recharge of the High Plains Aquifer. Of the total groundwater stored in this vast aquifer, 65% occurs in Nebraska and over half of that lies under the Sand Hills. The groundwater connection is obvious throughout the region. Due to the high water table, interdunal valleys in portions of the Sand Hills contain extensive complexes of lakes, wetlands, and naturally sub-irrigated wet meadows, which together cover over 10% of the landscape.

The Sand Hills Biocomplexity Project is a major federal project led by Professor Wedin. The project is aimed at testing whether:

  1. Evapotranspiration (ET) from wet valleys buffers the impacts of short-term drought on upland grasslands through local climate feedbacks. (resistance stability)
  2. When wetlands go dry, the combined effect of lost upland grass cover and lost wetland ET creates a desertification feedback that amplifies drought impacts.
  3. Since subregions of the Sand Hills differ in their extent of interdunal wetlands, subregions respond differently to paleo and historic droughts, thus enabling landowners to prepare for future droughts.
  4. Increased groundwater recharge when dunes are bare hastens the rise of groundwater levels, which, together with the rapid recovery of warm season grasses, restabilizes the dunes. (resilience stability)

The project's Grassland Destabilization Experiment (GDEX) is studying what happens to a Sand Hills dune when the vegetation dies. Researchers have created 10 circular plots at the Barta Brothers Ranch, each 120 meters in diameter, and used herbicide to kill all the vegetation on several of them. The plots are kept clear of vegetation, so that information on vegetation coverage, root mass, soil organic matter, and sand movement may be monitored and recorded to determine the stability of the plots. Results indicate that the Sand Hills may be more stable than previously thought; that is, ersosion is just starting to occur were vegetation was killed two years ago. Additional studies are needed to determine what happens when sand dunes become mobile.

As a part of this project, Professor Vitaly Zlotnik carries out research on groundwater recharge, hydraulic properties of the dune cover, and the climate change effects on groundwater recharge.

Project Support National Science Foundation
Project Website http://sandhills-biocomplexity.unl.edu/
Report
Current Status n/a
Topic Wildlife
Project's Primary Contact Information
Name Pegg, Mark
Unit School of Natural Resources
Email mpegg2@unl.edu
Phone 402-472-6824
Web Page http://snr.unl.edu/aboutus/who/people/faculty-member.asp?pid=739
Project Information
Title Habitat Usage of Missouri River Paddlefish Project
Description Sediment from the Niobrara River has created a delta area near the headwaters of Lewis and Clark Lake, the reservoir formed by Gavins Point Dam on the Missouri River. This sediment aggregation has reduced reservoir volume and threatens to fill the reservoir; therefore, restoration of reservoir capacity has been proposed by means of high-velocity water releases from upstream mainstem dams. Biologists, however, have reported that this delta area may serve as spawning grounds for native fishes like paddlefish, and may provide suitable spawning habitat for federally endangered pallid sturgeon. This situation has created a unique paradox where information is needed to provide insight into fulfilling both the river management needs and biological needs in the Missouri River. This project will use paddlefish telemetry to study spawning success.

Click here to read Brenda Pracheil's dissertation on Paddlefish populations

Project Support Nebraska Environmental Trust
Project Website
Report Pracheil et al_Fisheries_2012.pdf
Current Status Completed
Topic Wildlife
Project's Primary Contact Information
Name Young, Chelsey
Unit Biology, UNK
Email youngca2@unk.edu
Phone 507-469-8284
Web Page
Project Information
Title A range-wide assessment of plains topminnow (Fundulus sciadicus) distribution and potential threats
Other(s) W. Wyatt Hoback, Biology UNK, hobackww@unk.edu; Keith Koupal, Biology UNK; Justin Haas 
Description The plains topminnow, Fundulus sciadicus, was once distributed from the Mississippi River to the Rocky Mountains, north to South Dakota and as far south as Oklahoma. Two centers of distribution are recognized. One is centered in Nebraska and the second is centered in Missouri. The geographic range of plains topminnow has decreased in the past decades. Plains topminnow are now considered a species of special concern in the state of Nebraska and listed as a Tier 1 species in the Nebraska Natural Legacy Project. Elimination of plains topminnow populations has been associated with introduction of invasive species, as well as loss of backwater habitats due to drought and lowered water tables. The objective of this project is to provide an updated assessment of plains topminnow distribution and population status as compared to all available historical records. Between 2004 and the present, sampling of plains topminnow revealed that in Nebraska 77% of historic Nebraska sites no longer contain plains topminnow populations. The sampling of remaining historic sites in Nebraska and neighboring states will continue in the 2009 sampling season.
Project Support n/a
Project Website
Report topminnow_range_reduction.pdf
Current Status Completed