NU Water-Related Research in Dawson County

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

Displaying 21 records found for Dawson County


Topic Crop Water Use
Project's Primary Contact Information
Name Irmak, Suat
Unit Biological Systems Engineering
Email sirmak2@unl.edu
Phone 402-472-4865
Web Page http://bse.unl.edu/sirmak2
Project Information
Title Mapping Spatial Distribution of Evapotranspiration and Other Energy Fluxes for Key Vegetation Surfaces
Other(s) Ayse Irmak, School of Natural Resources, airmak2@unl.edu; Shashi Verma, School of Natural Resources, sverma1@unl.edu; Derrel Martin, Biological Systems Engineering, dmartin2@unl.edu 
Description Efficient use of water resources in semi-arid agro-ecosystems of Nebraska is an important issue because of the rapid depletion of freshwater resources and drought conditions, and degradation of groundwater quality in recent years. Proper planning and management, and related policy decisions of water resources require accurate quantification of evapotranspiration (ET). An extensive field campaign has been initiated with the Central Platte Natural Resources District and UNL in the Central Platte River Valley to measure ET and other surface energy fluxes for various vegetation surfaces. The vegetation surfaces include, center pivot-irrigated grassland, rainfed grassland, rainfed winter wheat, center pivot-irrigated alfalfa, Phragmites australis-dominated cottonwood and willow stand plant community, irrigated maize, irrigated soybeans. A deluxe version of Bowen ratio energy balance systems are being used to measure ET and other surface energy balance components, soil moisture, and plant physiological parameters in each research site.
Project Support Central Platte Natural Resources District
Project Website
Report
Current Status Underway
Topic Crop Water Use
Project's Primary Contact Information
Name van Donk, Simon
Unit West Central Research and Extension Center
Email svandonk2@unl.edu
Phone 308-696-6709
Web Page http://westcentral.unl.edu/web/westcentral/svandonk
Project Information
Title Determining the effect of the amount and timing of irrigation on corn production, using subsurface drip irrigation (SDI)
Description

It is important to learn how to grow crops with limited amounts of water and to determine crop water use with SDI. In 2007 a field study with corn was initiated that will be continued in 2008 and 2009. The treatments are:

  • Rainfed (no irrigation)
  • 0.50 ET (meet 50% of evapotranspiration requirements) throughout the season
  • 0.75 ET throughout the season
  • 1.00 ET throughout the season
  • no irrigation at first, 1.00 ET during 2 weeks around tasseling, then no more irrigation after that
  • 0.50 ET at first, 1.00 ET during 2 weeks around tasseling, then 0.50 ET after that
  • 0.50 ET at first, 1.00 ET during 3 weeks around tasseling, then 0.50 ET after that
  • 0.50 ET at first, 1.00 ET during 4 weeks around tasseling, then 0.50 ET after that
  • 0.75 ET at first, 1.00 ET during 4 weeks around tasseling, then 0.75 ET after that

Using SDI may not only increase water use efficiency, but also nutrient use efficiency when applying nutrients through the SDI system. This study was conducted at WCREC to assess the effect of different in-season nitrogen (N) application (via SDI) timings on corn production and residual soil nitrate-nitrogen (NO3-N). We evaluated the effect of three N application timing methods at two N application rates (UNL recommended rate and the UNL rate minus 20%) on corn grain, biomass yield, and end-of-study distribution of residual soil NO3-N.

In 2006, there were no significant differences in corn grain yields between the two N application rates. In 2007, the grain yield under the UNL recommended N rate was significantly higher (3.0 bu/ac) than under the UNL-minus-20% N rate. In both years, grain yield and biomass production for the N application timing treatments were not significantly different. The lack of response to different N application timing treatments indicates that there is flexibility in N application timing for corn production under SDI. This two-year field study was published in Soil Science.

Impact: This study helps us better understand the most appropriate times to apply N with SDI (underground fertigation). If applied at inappropriate times, nitrates are not used by the crop and may leach into groundwater. If N use is minimized, the producer's cost can be minimized.

Project Support n/a
Project Website
Report SDI_Corn_Yield.pdf
Current Status Completed
Topic Extension
Project's Primary Contact Information
Name van Donk, Simon
Unit West Central Research and Extension Center
Email svandonk2@unl.edu
Phone 308-696-6709
Web Page http://westcentral.unl.edu/web/westcentral/svandonk
Project Information
Title West Central Research and Extension Center - Gudmundsen Sandhills Laboratory
Other(s) Jim Goeke, West Central Research and Extension Center, jgoeke1@unl.edu 
Description

The University of Nebraska West Central Research and Extension Center is a research and extension facility of the University of Nebraska Institute of Agriculture and Natural Resources (IANR). It serves as the site for field-based research and extension involving faculty and graduate students in eight IANR departments. West Central consists of approximately 1,800 acres of which 1,100 acres are in pasture with the remaining in dryland and irrigated cropping systems. West Central delivers research-based education and information to citizens throughout the state. Extension specialists and educators are committed to excellence, conducting educational programs customized to meet the needs of Nebraskans. These educational programs, delivered via a variety of methods, are offered through federal, state and county partnership arrangements and provide research-based information and other educational resources to the 20-county West Central district and beyond.

The Gudmundsen Sandhills Laboratory (GSL), a 13,000 acre working ranch in the Nebraska Sandhills, is also part of West Central. GSL is situated over a relatively small portion of the High Plains Aquifer where saturated thickness exceeds 1000 feet. GSL also features a valley with a live stream, a drained valley with wet meadows, an adjacent lake, dry valleys, and many dune types so that literally all the surface and groundwater locales in the Sandhills are represented and available for research. In 2004 a U.S. Climate Reference Network station was established at GSL to provide future long-term observations of temperature and precipitation accurate enough to detect present and future climate change.

Project Support Varies according to program and project - for more information see http://www.westcentral.unl.edu
Project Website http://westcentral.unl.edu/web/gudmundsen/
Report
Current Status Continuous
Topic Groundwater
Project's Primary Contact Information
Name Perera-Estrada, Hugo
Unit Agronomy and Horticulture
Email hpereaestrada2@unl.edu
Phone 402-472-6085
Web Page
Project Information
Title Modeling Groundwater Nitrate Transport Beneath a Ground Water Quality Management Area in the Central Platte Region of Nebraska
Other(s) Mary E. Exner, School of Natural Resources, mspalding1@unl.edu; Roy Spalding, Agronomy and Horticulture, rspalding1@unl.edu 
Description A Ground Water Quality Management Area (GWQMA) is being evaluated to determine the effectiveness of producer practices in reducing high nitrate levels that result from excessive N-fertilizer and irrigation water applications. The assessment of nitrate movement in the primary and secondary aquifer relies on simulating groundwater flow and contaminant transport beneath the 588 km2 Phase III GWQMA. The Platte River is in hydraulic connection with the aquifer and forms the southern boundary of the model. The northern boundary parallels the northern edge of the GWQMA. Hydraulic conductivities from test hole data, irrigation well pedigree information and nitrate concentrations from 1988 to 2003 were input to a 3-D groundwater finite difference model. A Neumann or second-type boundary condition was established for the northern and southern model boundaries. Prescribed heads (Dirichlet-type boundary condition) were imposed on the upgradient and downgradient sides of the GWQMA. The thicknesses of the primary (upper) and secondary aquifers are somewhat variable in the investigated area as are hydraulic conductivities in the secondary aquifer. The groundwater model was calibrated in the steady-state mode with hydraulic head data from 1988 to 2003. The flow path and travel times within the study area result in an approximate evaluation of the susceptibility to nitrate contamination with transport. Results are described in 2-D and 3-D graphical visualizations. Hydraulic head and water quality data from adjacent monitoring wells screened in either the primary or secondary aquifers were used to quantify nitrate transport between the aquifers.
Project Support n/a
Project Website http://www.usawaterquality.org/conferences/2009/PDF/CEAP-all/Perera-Estrada09.pdf
Report
Current Status Completed
Topic Groundwater
Project's Primary Contact Information
Name Spalding, Mary Exner
Unit School of Natural Resources
Email mspalding1@unl.edu
Phone 402-472-7547
Web Page http://snr.unl.edu/aboutus/who/people/faculty-member.asp?pid=111
Project Information
Title Evaluation of the Effectiveness of Selected Farm Practices in Reducing Groundwater Nitrate
Other(s) Hugo Perera-Estrada, Agronomy and Horticulture, hpereaestrada2@unl.edu; Megan L. Liedte, Statistics; Roy Spalding, Agronomy and Horticulture, rspalding1@unl.edu 
Description Data from 25,961 producer reports and 1,935 irrigation wells were used to assess the effectiveness of management practices within 588 km2 of intensely irrigated corn production in the Platte River drainage in central Nebraska. The area has been regulated as a Phase III Ground Water Quality Management Area by the local Natural Resources District (NRD) for 19 years. The initial spatial analysis of the 1987 groundwater nitrate concentrations revealed an obvious concentration demarcation. Concentrations in the very contaminated northern area averaged 25.7 mg NO3-N/L while those in the southern portion averaged 9.4 mg NO3-N/L. Groundwater nitrate concentrations in the north are significantly correlated with time (r2 = 0.87) and decreased at an average annual rate of 0.24 mg NO3-N/L between 1987 and 2005. No significant concentration trend occurred in the southern area. During the 19 years the amount of N removed in grain increased at an average annual rate of 2 kg N/ha. In the north the association between the increase in N removed in grain and decrease in groundwater NO3-N concentrations is significant. The acreage converted from furrow to sprinkler irrigation increased threefold between 1988 and 2003. In the north the increase in sprinkler-irrigated acres is associated with the decrease in groundwater NO3-N concentrations. The NRD- recommended N-fertilizer rate for each corn field in the Phase III area is based upon a realistic yield goal and NRD-modified university N-fertilizer recommendation with credits for residual soil N and N available in irrigation water. From 1988 to 2003 N-fertilizer rates on 62 to 88% of the fields were within ± 56 kg N/ha (50 lb N/ha) of the NRD recommendation. The remaining fields were more likely to be fertilized at rates greater than 56 kg N/ha in excess of the recommendation than receive N at rates more than 56 kg N/ha below the NRD recommendation.
Project Support n/a
Project Website http://www.usawaterquality.org/conferences/2009/PDF/CEAP-all/Exner09.pdf
Report
Current Status Completed
Topic Hydraulics
Project's Primary Contact Information
Name Szilagyi, Joe
Unit School of Natural Resources
Email jszilagyi1@unl.edu
Phone 402-472-9667
Web Page http://snr.unl.edu/aboutus/who/people/faculty-member.asp?pid=119
Project Information
Title Identifying Cause of Declining Flows in the Republican River
Description

The Republican River, shared by three states, Colorado, Nebraska, and Kansas, has yielded depleted streamflow at the Nebraska-Kansas border for about 20 years when compared to values preceding 1970. Based on model results estimating the average annual water balance of the basin, it is concluded that the observed decline in runoff cannot be explained by changes in climatic variables over the area; rather, it is the result of the combined effects of the following human activities: crop irrigation, change in vegetative cover, water conservation practices, and construction of reservoirs and artificial ponds in the basin. These human-induced changes have one property in common: they all increase the amount of water being evaporated over the basin, thereby reducing the amount of water available to runoff.

More about this research in the Journal of Water Resources Planning and Management

Project Support UNL School of Natural Resources
Project Website n/a
Report
Current Status Completed
Topic Hydrology
Project's Primary Contact Information
Name Chen, Xun-Hong
Unit School of Natural Resources
Email xchen2@unl.edu
Phone 402-472-0772
Web Page http://snr.unl.edu/aboutus/who/people/faculty-member.asp?pid=19
Project Information
Title Hydrologic Connections in the Central Platte River Basin
Other(s) Mark E. Burbach, Conservation and Survey Division, mburbach1@unl.edu; Cheng Cheng, School of Natural Resources, ccheng2@unl.edu 
Description

The hydrologic properties of channel sediments have an important role in controlling hydrologic process in streams. This study focused on the water exchange between a stream and an aquifer induced by groundwater withdrawal, with the purpose of investigating the interbedded feature of channel sediments and to evaluate its effects on the calculation of streamflow depletion. Field work was conducted at nine study sites between Kearney and Columbus during the summers of 2005 and 2006. Direct-push techniques were used to produce electrical conductivity logs and to collect sediment cores. Permeameter tests were conducted on the sediment cores. Stream-aquifer simulation models were used to evaluate streamflow depletion for various types of channel sediments.

Sediment core samples were categorized into four groups:

  • sand and gravel,
  • sand and gravel with interbedded silt and clay layers,
  • fine sand with silt or clay layers, and
  • silt and clay with some sand and gravel.

In general coarse sediments occur in the western part of the study area, and the amount of fine sand, silt and clay increases eastward along the river. However, the sediments in the top two meters are about the same for all the sites, consisting mainly of sand and gravel.

Project Support Central Platte Natural Resources District, Upper Big Blue Natural Resources District, U.S. Geological Survey (through the University of Nebraska-Lincoln Water Center), U.S. Environmental Protection Agency
Project Website
Report Chen Hydrologic Connections.pdf
Current Status Published in Journal of Hydrology 2008 352:250-266
Topic Invasive Species
Project's Primary Contact Information
Name Allen, Craig (advisor)
Unit Nebraska Cooperative Fish and Wildlife Research Unit
Email callen3@unl.edu
Phone 402-472-0229
Web Page http://snr.unl.edu/aboutus/who/people/faculty-member.asp?pid=647
Project Information
Title The Effect of Common Reed (Phragmites australis) on River Otter (Lontra canadensis) Habitat Use
Other(s) Amy Williams, amy_ruth18@hotmail.com; Sam Wilson, Nebraska Game and Parks Commission, sam.wilson@nebraska.gov 
Description The river otter (Lontra canadensis) is a threatened species in Nebraska and little is known about its local ecology. The recent invasion of the Platte River by the common reed (Phragmites australis) has altered the riverscape and could have negative effects on otters. Since the reintroduction of river otters to several of Nebraska's river basins beginning in the late 1980's, there have been no quantitative studies examining the status of the population or habitat use of river otters in the state. The recent invasion of P. australis in the Big Bend region of the Platte River has made the need to fill this knowledge gap more critical. We are examining the effects of P. australis on river otters by determining if otters use river ways dominated by P.australis or den in areas of P. australis more or less than expected relative to availability. Sixteen otters were trapped, radio tagged, and tracked between 2006 and 2009. 517 den/resting locations were identified, 127 of which were unique locations. Den/resting site habitat use was compared to availability to determine if otters were using P. australis in proportion to availability. Females use unique sites in P. australis more than expected but males do not. When all locations were analyzed, both males and female used P. australis in proportion to availability. P. australis provides cover for females and is likely used for resting locations when traveling with pups. Information on otter abundance and habitat use from this study will support the creation and implementation of a state river otter management plan and ensure the persistence of a viable otter population in Nebraska.

Project Support

Nebraska Cooperative Fish and Wildlife Research Unit, Nebraska Game and Parks Commission
Project Website http://snr.unl.edu/necoopunit/research.main.html#river_otters
Report
Current Status Completed
Topic Pollution Prevention
Project's Primary Contact Information
Name Comfort, Steve
Unit School of Natural Resources
Email scomfort1@unl.edu
Phone 402-472-1502
Web Page http://snr.unl.edu/aboutus/who/people/faculty-member.asp?pid=21
Project Information
Title Using Slow-Release Permanganate Candles to Remove TCE From a Low Permeable Aquifer at a Former Landfill
Other(s) Mark Christenson, School of Natural Resources; Ann Kambhu, Department of Civil Engineering 
Description

Past disposal of industrial solvents into unregulated landfills is a significant source of groundwater contamination. In 2009, we began investigating a former unregulated landfill with known trichloroethene (TCE) contamination. Our objective was to pinpoint the location of the plume and treat the TCE using in situ chemical oxidation (ISCO).

While the characteristics of the low permeable aquifer at the Cozad site dictates that additional field monitoring will be needed for several years to fully determine the efficacy of the slow release candles, initial field results and the supporting laboratory results presented indicate that slow-release permanganate candles may be an effective means of treating chlorinated solvents in low permeable zones. Potential advantages to the candle technology are that they negate the need for specialized equipment (mixing trailer, pumps, hoses, etc.), curtail health and safety issues associated with handling liquid oxidants, and when used in a barrier design, could potentially provide a long-term solution for controlling contaminant migration.

Project Support United States Environmental Protection Agency, University of Nebraska School of Natural Resources and Water Science Laboratory
Project Website n/a
Report Comfort_TCE.pdf
Current Status Completed
Topic Production Agriculture
Project's Primary Contact Information
Name Supalla, Raymond
Unit Agricultural Economics
Email rsupalla1@unl.edu
Phone 402-472-1792
Web Page http://agecon.unl.edu/supalla
Project Information
Title Economic and State Budget Cost of Reducing the Consumptive Use of Irrigation Water in the Platte and the Republican Basins
Other(s) Brian McMullen, Agricultural Economics, bmcmullen2@unl.edu 
Description

The terms of the Cooperative Agreement for the Platte Basin and the Supreme Court settlement decision for the Republican Basin both require that Nebraska reduce its consumptive use of irrigation water. This analysis evaluated the economic and the budgetary costs of meeting these requirements. Both the on-farm and off-farm costs were evaluated for both land retirement and water allocation programs, implemented in several different ways, over three alternative time periods, 10, 25 and 50 years.

The on-farm economic costs were defined as the change in net farm income associated with less irrigation. Off-farm economic costs were defined as the statewide change in household income resulting from changes in irrigation, as the effects ripple through the Nebraska economy. Budgetary costs were defined as the cost to the state budget (taxpayers) of policies which compensate irrigators for reducing consumptive use are implemented. Statewide economic costs were found to be lower for land retirement than for allocation programs, assuming the same total change in consumptive use. Total budgetary costs depended primarily on: where the irrigation reductions occurred (proximity to river); on how long the program was continued (number of years), and on whether irrigation was reduced voluntarily with incentives, or by regulation, or by some combination of regulation and incentives. It was found that policy makers could minimize the cost of reducing consumptive use from irrigation and augmenting stream flow by purchasing rather than leasing irrigation rights, by using a regulatory rather than a willing seller incentive approach, and by reducing irrigation at locations close to the river.

More on this research in a UNL Agricultural Economics working paper

Project Support n/a
Project Website
Report
Current Status Completed
Topic Property Values
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 Ongoing UNO/UNL Research on the Determinants of Agricultural Land Values: How Irrigation Contributes to Land Values in Western and Central Nebraska
Other(s) Nick Schmitz, UNO Real Estate Research Center 
Description

Hedonic (mass appraisal) land valuation models were estimated in the Republican and Platte watersheds of Central and Western Nebraska. These models are based on assumption that the buyers and sellers of agricultural land are able to accurately assess the value of irrigation when negotiating sale contract prices, and that irrigation equipment can be distinguished from land and irrigation values. Alternative models were estimated using various combinations of explanatory variables (all measured at the parcel level of analysis). These include: soil productivity measures, topography precipitation, parcel size, cropping patterns, topography, aquifer thickness, well pumping capacity, distances to elevators and towns, and irrigation systems.

The location of all agricultural land sales statewide (2000-2007) and estimated irrigation values in the Platte and Republican Watersheds were identified. Preliminary mass appraisal model results were summarized in tables and the locations of retired irrigation parcels in the Republican Watershed (as part of a 2006 NE DNR and USDA Pilot Program) were identified. The value of irrigated cropland is on average $615/acre (this is the value of irrigated cropland only and does not include the value dryland corners within pivot systems). As well, there are numerous areas and site-specific parcels within the watershed with both lower and higher irrigation values. In fact, we have calculated irrigation values for all of the natural resource districts in the Republican watershed: they range from $488/acre to $948/acre. These estimates are still considered 'preliminary' and may be subject to revision. These irrigation values also do not account for premiums above and beyond marginal market values that farmers and landowners will likely require to willingly participate in future irrigation retirement programs.

More on this research in a journal of the Western Agricultural Economics Association

Project Support U.S. Department of Agriculture Water and Watershed Program
Project Website
Report
Current Status Complete (up to 2007)
Topic Riparian Vegetation Water Use
Project's Primary Contact Information
Name Kilic, Ayse
Unit Center for Advanced Land Management Information Technologies
Email akilic@unl.edu
Phone 402-472-5351
Web Page http://snr.unl.edu/aboutus/who/people/faculty-member.asp?pid=860
Project Information
Title Estimating Riparian Water Use: An Application of Remote Sensing
Description The goal of this project is to quantify riparian evapotranspiration (ET) by utilzing satellite and air-borne remote sensing data on selected watersheds in the North Platte River. The results will be used to develop guidelines on riparian water use.
Project Support UNL Office of Research Layman Award
Project Website
Report
Current Status Completed
Topic Survey
Project's Primary Contact Information
Name Joseph Hamm
Unit jhamm2@nebraska.edu
Phone 402-472-5678
Web Page http://ppc.unl.edu/
Project Information
Title Platte River Habitat Partnership Survey
Other(s) Lisa Pytlik Zillig, Public Policy Center, lpytlikz@nebraska.edu, Alan Tomking, Public Policy Center, atomkins@nebraska.edu 
Description

Nebraska’s native prairies are a valued resource and under constant anthropogenic demand and degradation. By engaging land owners in voluntary programs, the Platte River Habitat Partnership aims to restore and enhance this important natural resource. In this project, the Public Policy Center conducted a survey to assess land owners’ perceptions of the Platte River Habitat Partnership to help direct the Partnership’s second phase. Specifically, land owners who live in the region covered by the Partnership but did not participate, and those that did participate in the Partnership were surveyed in order to answer four key questions: 1. How knowledgeable are these land owners about the Partnership? 2. What is the nature of these land owners’ interactions with the Partnership? 3. How is the Partnership itself generally perceived by these land owners? 4. What would encourage land owners who had not participated in the Partnership to participate?

Project Support The Nature Conservancy
Project Website http://ppc.unl.edu/project/PlatteRiverHabitatPartnershipSurvey
Report PRHP_Report.pdf
Current Status Completed
Topic Water Quality
Project's Primary Contact Information
Name Chen, Xun-Hong
Unit School of Natural Resources
Email xchen2@unl.edu
Phone 402-472-0772
Web Page http://snr.unl.edu/aboutus/who/people/faculty-member.asp?pid=19
Project Information
Title Distribution Patterns of Nitrate-Nitrogen in Groundwater
Other(s) Fujiang Wen, Doctoral Candidate in the School of Natural Resources, fwen314@yahoo.com 
Description

This paper evaluated spatial patterns of nitrate-nitrogen contamination of groundwater in the High Plains Aquifer in the area of Dawson, Buffalo and Hall counties in the South-Central Platte River Valley of Nebraska. Geostatistical approaches including ordinary kriging, indicator kriging and cokriging, were used to analyze 1514 samples drawn from 465 irrigation wells over a 30-year period. The spatial trends of the nitrate-N concentration suggested that about one third of the aquifer in the area had been contaminated by nitrate-N above a level of 5 ppm.

The small areas along with the South-Central Platte River Valley were classified as high risk with the nitrate-N level above 10 ppm. The probabilistic maps exceeding thresholds (10 and 5 ppm) for the nitrate-N concentrations of the groundwater were created to assess vulnerability. The areas with the nitrate-N levels exceeding 10 ppm at an extremely high risk (>75%) were delineated for the future nitrate priority areas of management. Temporal trends of the nitrate-N contamination at 465 sampling locations were analyzed for a period of 30 years. Thirty-seven (37) sampling wells, accounting for 8.0% of the total sampling wells, were identified with an increasing trend, in which the maximum increase was estimated at 4.20 ppm per five-year. Twenty-nine (29) wells were identified with a decreasing trend, in which the average decrease was 0.48 ppm per five-year. It was concluded that the groundwater nitrate-N contamination in some areas, such as the middle area of Buffalo County, was improving, but was worsening in other areas, such as the middle portion of Hall County and the south-eastern corner of Buffalo County. It was found that groundwater irrigation level (or well density) has a positive correlation with high concentration of nitrate-N.

Project Support Central Platte Natural Resources District
Project Website
Report
Current Status Completed
Topic Water Quality
Project's Primary Contact Information
Name Tang, Zhenghong
Unit Architecture
Email ztang2@unl.edu
Phone 402-472-9281
Web Page http://architecture.unl.edu/people/bios/tang_zhenghong.shtml
Project Information
Title Assessment of Sedimentation and Water Quality Conditions in the Rainwater Basin's Playa Wetlands
Other(s) Mark Kuzila, School of Natural Resources, mkuzila1@unl.edu; Xu Li, Department of Civil Engineering, xuli@unl.edu; Amy Burgin, School of Natural Resources, aburgin2@unl.edu 
Description

The overall goal of this project is to prioritize watershed restoration/acquisition programs in the Rainwater Basin (RWB) by examining playa wetlands’ sedimentation and water quality conditions using the Revised Universal Soil Loss Equation 2 (RUSLE2) and the fly ash technology.

Three specific tasks are included in this project:

  1. Calculate and map the sedimentation rates and the age of deposition for all playa wetlands in RWB
  2. Consolidate existing water quality data of the RWB playa wetlands and evaluate the key factors influencing playa wetland water quality
  3. Assess the effects of sedimentation control practices and prioritize future watershed restoration/acquisition programs

The final products of this project include:

  1. An atlas of wetland sedimentation maps and a risk report highlighting the areas in watersheds with the highest sedimentation rates
  2. A geodatabase and an evaluation report on the water quality conditions of the playa wetlands in the RWB
  3. A written assessment report for sedimentation control practices and a watershed index to prioritize future conservation/acquisition programs
Project Support U.S. Environmental Protection Agency
Project Website http://www.unl.edu/playawetlands/
Report
Current Status Underway
Topic Water Quality
Project's Primary Contact Information
Name van Donk, Simon
Unit West Central Research and Extension Center
Email svandonk2@unl.edu
Phone 308-696-6709
Web Page http://westcentral.unl.edu/web/westcentral/svandonk
Project Information
Title Quantify the extent of vertical hormone movement through vadose zone soils
Description

The extent of exogenous hormone use in beef cattle production, in addition to endogenous hormones, increases the risk of hormone residues entering the environment when manure is applied to soil. This research will provide key information on the environmental fate of hormones commonly found in feedlot cattle manure. This information is critical in developing management practices for concentrated animal feeding operations and farms that will reduce environmental risks associated with land application of manure.

This research will be conducted using the specialized percolation lysimeters research site at the West Central Research and Extension Center during 2008 and 2009. The site contains fourteen percolation lysimeters installed at the center of each of fourteen field plots. Each plot is 40 ft m by 40 ft. Each lysimeter contains an undisturbed soil core with a diameter of 3 ft and a depth of 8 ft and has porous extractors at the bottom, which allows the extraction of leachate from unsaturated soil using a vacuum pump. These lysimeters have been used successfully for several nitrate-leaching experiments. Water samples, which represent the water that is leached from the crop root zone, can be collected at the bottom of these lysimeters and will be used to determine the amounts and types of hormones leaching below the crop root zone. Treatments will consist of treated stockpiled manure, treated compost manure, and a check (no manure application). The manures will be applied to the lysimeters and field areas adjacent to the lysimeters in the spring of 2008 at application rates to satisfy the nitrogen needs of corn based on University of Nebraska recommendations. The check plots will receive commercial nitrogen fertilizer to match the manure N availability. Three treatments and three replications (nine lysimeters in nine plots) will be used for this study.

Wheat will be planted in the lysimeters and adjacent plots during both years. Soil moisture from each plot will be measured weekly at 1 ft depth increments to a depth of 7 ft, using the neutron probe method. Water samples will be collected every three weeks from the lysimeters from April to November in both years. Soil samples will be collected at six depth increments down to a depth of 8 ft, four times between application and October in 2008, and three times from April to August in 2009. To reduce sampling errors created by spatial variability within each plot, five sub-samples will be taken from each depth. The sub-samples will then be mixed to create one composite sample. Background soil profile samples will be taken before the manure is applied. Sampling depths will be increased as needed, based on the confirmed movement of hormones of interest through the soil profile. Soil and leachate samples will only be taken during the periods when the ground is not frozen (April to November), when movement of water is expected.

Project Support n/a
Project Website
Report
Current Status Continuing
Topic Watershed Management
Project's Primary Contact Information
Name Allen, John C.
Unit Agricultural Economics
Email jallen1@unl.edu
Phone 435-797-9732
Web Page
Project Information
Title Socio-Cultural Study of the Middle Platte River Region of Nebraska: Building Capacity for Community-Based Conservation
Description Telephone surveys, focus group interviews, and in-depth interviews were conducted in 1997 and community profiles developed in 1998 to provide an integrated picture of the social and cultural factors that influence how Middle Platte River residents and communities perceive the river; where their futures fit with the perceived best case scenarios; and the future they see for themselves, their family, and their community.
Project Support U.S. Environmental Protection Agency
Project Website http://watercenter.unl.edu/PRS/PlatteRiverReports/Socio-Cultural%20Study%20of%20the%20Middle%20Platte%20River.pdf
Report
Current Status Completed
Topic Watershed Management
Project's Primary Contact Information
Name Hoagland, Kyle
Unit Nebraska Cooperative Fish and Wildlife Research Unit
Email khoagland1@unl.edu
Phone 402-472-9544
Web Page http://snr.unl.edu/aboutus/who/people/faculty-member.asp?pid=50
Project Information
Title Making Adaptive Management Meaningful: Translating Science Learning into Policy Decision-Making
Other(s) Chad Smith, School of Natural Resources, smithc@headwaterscorp.com 
Description

Adaptive management has been and continues to be implemented around the country and world, yet few examples exist of programs successfully implementing all six steps (Assess, Design, Implement, Monitor, Evaluate, and Adjust) of adaptive management. A key break point in this process seems to be synthesizing collected data and using that synthesis to tell a story about what data say in regard to key questions and hypotheses in a way that is useful to decision-makers and results in positive changes in management or policy.

Chad Smith continues his research into the gap between science and decision-making in adaptive management programs and tools to successfully bridge that gap.

GOALS:

  1. Explore the science and policy interface in a comparative study of several adaptive management programs
  2. Provide specific background on this issue as it relates to the Platte River Recovery Implementation Program
  3. Showcase decision analysis and other tools that can be used as decision support in the Platte River and other adaptive management programs
  4. Discuss opportunities for and challenges to bridging the science/policy gap

Smith is applying learning from his research in the real world, serving as Adaptive Management Plan implementation coordinator for the Platte River Recovery Implementation Program. He is also co-lead of a small team writing an Adaptive Management Plan for the Middle Rio Grande Endangered Species Collaborative Program.

Project Support n/a
Project Website http://snr.unl.edu/necoopunit/research.main.html#making_adaptive_management
Report
Current Status Continuing
Topic Watershed Management
Project's Primary Contact Information
Name Jenkins, Allan
Unit Economics
Email
Phone
Web Page
Project Information
Title Middle Platte Socioeconomic Overview
Description This report was published in February 1999 and designed to provide a common body of knowledge to all groups engaged in decisions regarding the Platte River. Recognizing that different decision-makers have different levels of prior knowledge concerning the Platte River, the author attempted to create a document suitable for a range of audiences that also facilitated discussion.
Project Support U.S. Environmental Protection Agency
Project Website http://watercenter.unl.edu/PRS/PlatteRiverReports/The%20Platte%20Watershed%20Program.pdf
Report
Current Status Completed
Topic Wildlife
Project's Primary Contact Information
Name Pegg, Mark (advisor)
Unit Nebraska Cooperative Fish and Wildlife Research Unit
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 Catfish Population Dynamics in the Platte River, Nebraska
Other(s) Tony J. Barada, abarada2@unl.edu 
Description

Catfish angling is popular throughout the United States and catfish are the most sought after fish species in the Platte River. However, catfish management in the Platte River is minimal as little is known about current populations. The objective of this study was to determine the current status of channel catfish and flathead catfish populations in the central and lower Platte River. Specifically, the study evaluated population characteristics including relative abundance, size structure, condition, age, growth and mortality.

Channel catfish are much more abundant than flathead catfish in the Platte River. The current Platte River channel catfish population appears to be average, comparable to many Nebraska and Midwestern rivers. Population characteristics displayed considerable variation along the Platte River and some longitudinal patterns were evident. Channel catfish in the central Platte River had lower relative abundances, higher condition, greater size structure, faster growth and lower mortality compared to lower Platte River channel catfish. Key factors likely influencing differences in channel catfish population characteristics are prey availability, flow modifications, habitat characteristics, tributary inflows and angler exploitation. Water manipulations from the Loup River Power Canal were also identified as a possible negative influence on lower Platte River channel catfish populations because hydropeaking is likely creating a stressful environment. However, channel catfish in the central Platte River appear to have benefited from recent high flows that likely increased productivity and food availability in the central Platte River.

Tony Barada's Master's Thesis on Catfish Population Dynamics in the Platte River

Project Support Nebraska Game and Parks Commission, Federal Aid in Sportfish Restoration
Project Website
Report
Current Status Graduate thesis project completed - thesis available at UNL CY Thompson Library (Call # LD3656 2009 .B373)
Topic Wildlife
Project's Primary Contact Information
Name Vivian, Lindsay A.
Unit Biology, UNK
Email lindsayviv@gmail.com
Phone 308-379-4587
Web Page
Project Information
Title Updating the Distribution and Population Status of the Platte River Caddisfly
Other(s) W. Wyatt Hoback, Biology UNK, hobackww@unk.edu 
Description The Platte River caddisfly, Ironoquia plattensis, was first described in 1999 from a warm water slough just south of Grand Island, NE. Using a benthic core sampling method, the investigators reported an average caddisfly larval density of 805 ± 194/m2. In 2004, there were no Platte River caddisflies observed at the 1999 study site. Ironoquia plattensis has been observed at five other locations in the central Platte region, but only two of the six historic populations are considered stable. Between 2002 and 2005, central Nebraska suffered an extensive drought, which could have taken its toll on the caddisfly. The sloughs where Ironoquia plattensis occur are typically wet nine months out of the year and dry during the summer. During the summer of 2009, four historic sites and one new, previously unrecorded site were sampled for larvae using a 30 cm D-frame net to sample a one meter swath a minimum of four times from each location. Using a GIS (Geographic Information Systems) predictive model and Google Earth, additional areas are being surveyed for the presence of the Platte River Caddisfly. The GIS model was created using local groundwater data from 1999 to the present, a soils layer, high resolution imagery, and a vegetation map analysis. If more populations are found, transects will be set up on the slough banks, and a quadrat will be used to quantify larval abundance in these areas. This will also be done at all historic locations. The goal is to establish the population status of this very rare insect of Nebraska which is adapted to the seasonal flows of the Platte River.

Lindsay Vivian's Master's Thesis on Platte River Caddisfly

For more information, read this journal article in the Annals of the Entomological Society of America

Project Support US Fish and Wildlife Service
Project Website
Report
Current Status In progress