NU Water-Related Research in Platte Valley WMA

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

Displaying 44 records found for Platte Valley WMA


Topic Climate
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 Dynamics of Climate Change in Central Platte Valley, Nebraska, as Indicated by Agro-meteorological Indices over 116 years (1893-2008): Preliminary Analyses
Other(s) Kabenge, Isa Mutiibwa, Denis 
Description

It has been established with a degree of confidence that the temperature of the earth’s atmosphere has increased by about 0.3 to 0.6 degrees C in the late 19th century (IPCC, 1997). Global warming can have substantial impact on agricultural production, water resources, and their interactions, by influencing microclimatic variables that drive plant physiological functions, such as surface air temperature, solar radiation, humidity, wind speed, rainfall frequency and amount, as well as hydrological balances, including evapotranspiration. Knowledge and analyses of long-term historical trends in agro-meteorological and hydrological parameters can aid in water resources design, planning, and man-agement. Historical trends in these variables can also help to relate agro-ecosystem production to climate change. We assessed the long-term trends in climatic variables. We quantified reference evapo-transpiration from solar and net radiation, vapor pressure deficit, wind speed, relative humidity, and air temperature from 1893 to 2008 using measured and estimated climatic data. Both alfalfa-reference and grass-reference evapotranspiration values were computed on a daily time step. We present historical trends in air temperature, relative humidity, preci-pitation, solar radiation, and evapotranspiration from 116 years of climatic observations and modeling results in the Central Platte Valley, Nebraska.

Conclusions from this project are:

  • Missing long-term climatic variables from 1893 to 1986 were reliably estimated for reference ET calculations.
  • Annual total rainfall amount showed an increasing trend over 116 years.
  • Both grass and alfalfa-reference ET fluctuated from year to year, but slightly decreased over the years.
  • Solar radiation slightly decreased due to increased rainfall/cloud cover.
  • Average vapour pressure deficit (VPD) did not change considerably.
  • Aridity index trend indicates a general tendency for Central City, NE area to shift toward more humid conditions, more so in the last 10 years.
Project Support
Project Website
Report
Current Status Completed
Topic Crop Nutrient Use
Project's Primary Contact Information
Name Ferguson, Richard
Unit Agronomy and Horticulture
Email rferguson1@unl.edu
Phone 402-472-1144
Web Page http://agronomy.unl.edu/ferguson
Project Information
Title Nutrient Management to Benefit Crops and Protect Water Quality
Other(s) Dean Krull, West Central Research and Extension Center, dkrull1@unl.edu 
Description

Ferguson is doing several projects with sites in Merrick and Hamilton counties focused on managing nitrogen applications to both benefit the crop and protect water quality.

  • The Impact of Controlled Release Urea Formulation on Nitrate Leaching Below the Root Zone of Irrigated Corn - Merrick County. This study is measuring nitrate leaching throughout the growing season on a coarse-textured soil planted to irrigated corn. Treatments include different nitrogen fertilizer sources and rates.
  • Relay Cropping Effects on Nitrate Accumulation in the Root Zone - Merrick County. This study evaluates the cumulative effect of the seed corn/winter wheat/relay-cropped soybean on nitrate accumulation in the root zone over the two year cropping system cycle.
  • In-Season Nitrogen Management Using Active Crop Canopy Sensors - Hamilton and Merrick counties. This series of studies on multiple crops (winter wheat, commercial corn, seed corn) at multiple sites investigates the use of active crop canopy sensors to control nitrogen fertilizer application during the growing season, using the crop to detect soil N supply rather than predicting soil N supply through soil sampling.
  • The Use of Polymers to Inhibit Nitrate Movement Below the Root Zone of Irrigated Corn - Merrick County. This study investigates the potential of various soil-applied polymers to retain nitrate in the root zone, preventing it from leaching into the vadose zone and eventually groundwater.
Project Support Central Platte NRD, Department of Agriculture, Agrium Inc., Georgia-Pacific, Dow AgroSciences, Monsanto Co., Nebraska Corn Board, Nebraska Environmental Trust
Project Website http://soilfertility.unl.edu/index.html
Report
Current Status Underway
Topic Crop Nutrient Use
Project's Primary Contact Information
Name Schepers, Jim
Unit Agronomy and Horticulture
Email Jim.Schepers@ARS.USDA.GOV
Phone 402-472-1513
Web Page http://www.agronomy.unl.edu/newfacultystaff/directory/schepers.html
Project Information
Title Managing Nitrogen Fertilizer Applications to Protect Groundwater
Description USDA-ARS scientists have research projects near Shelton, near Giltner, and about seven miles north of Central City which deal with protecting groundwater by carefully managing nitrogen fertilizer applications to corn and wheat. One cropping system involves seed corn production, which is assumed to be environmentally unfriendly. Our strategy is to plant wheat as a scavenger crop after the seed corn is harvested. In early June, soybeans are inter-seeded into the wheat. Both wheat and soybean function as scavenger crops and essentially eliminate the potential for nitrate leaching. A component of this management strategy is to use active (no sunlight required) crop canopy sensors to monitor plant chlorophyll (greenness) and biomass (vigor) while driving through the field to determine if more nitrogen is required by wheat or corn and automatically applying additional fertilizer while at that spot in the field. These technologies allow producers to use the crop as a bio-sensor of nitrogen needs and optimize nitrogen supplied by other sources (soil organic matter, manure, irrigation water).
Project Support U.S. Department of Agriculture - Agricultural Research Service
Project Website http://www.nue.okstate.edu/
Report
Current Status n/a
Topic Crop Water Use
Project's Primary Contact Information
Name Cassman, Ken
Unit Nebraska Center for Energy Sciences Research
Email kcassman1@unl.edu
Phone 402-472-5554
Web Page http://agronomy.unl.edu/cassman
Project Information
Title Crop Water Productivity Project
Other(s) Patricio Grassini, Agronomy and Horticulture, 
Description

This project will first establish benchmarks for irrigated corn within the Tri-Basin Natural Resources District and more broadly for the state and the High Plains. On-farm data from the Tri-Basin area will be compared with the benchmarks to estimate gaps between actual yields and optimum yields attainable with efficient water use. The goal is to adjust crop management to get greater yields with the same or a lesser amount of irrigation water. A 10% savings in irrigation water could total 90,000 acre feet and reduce annual pumping costs in Nebraska by $4 million. Farmers contributing to yield gaps will be identified in the project's first year; management advice and tools to help farmers improve yields and water productivity will be the focus of the second year.

Project Support Water, Energy and Agriculture Initiative - Nebraska Corn Board, Nebraska Soybean Board, UNL Agricultural Research Division, Nebraska Public Power District through the UNL Nebraska Center for Energy Sciences Research
Project Website
Report Grassini_Corn_Efficiency.pdf
Current Status Completed
Topic Crop Water Use
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 Data for Estimating Crop Water Use
Other(s) Ayse Kilic, School of Natural Resources, akilic@unl.edu 
Description

The University's High Plains Regional Climate Center (HPRCC) operates automated weather monitoring stations that take the essential information for calculating the Penman and Penman-Montieth reference evapotranspiration estimates. The estimates serve as the basis for estimating crop water use and as such are an essential element of the water budget for the hydrological cycle. These stations also monitor the soil moisture at four levels (10, 25, 50, and 100 cms) in the soil profile. The HPRCC is collecting hourly data from stations in Clay Center, Curtis, Holdrege, Imperial, McCook, Red Cloud, and Smithfield.

Project Support National Climatic Data Center
Project Website http://hprcc.unl.edu
Report
Current Status Continuing
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 Crop Water Use and Water Use Efficiency
Project's Primary Contact Information
Name Abunyewa, Akwasi
Unit Agronomy and Horticulture
Email akwasi_abunyewa@yahoo.com
Phone
Web Page
Project Information
Title Skip-Row and Plant Population Effects on Sorghum Grain Yield
Other(s) Richard Ferguson, Agronomy and Horticulture, rferguson@unl.edu; Charles Wortmann. Agronomy and Horticulture, cwortmann2@unl.edu; Drew Lyon, Panhandle Research and Extension Center, dlyon1@unl.edu; Stephen Mason, Agronomy and Horticulture, smason1@unl.edu; Robert Klein, West Central Research and Extension Center, rklein1@unl.edu 
Description This research conducted in Clay, Gosper, Frontier, Hayes, Center, Lincoln, Red Willow, and Cheyenne Counties from 2005 to 2007 evaluated the effect of skip-row configuration and planting population on sorghum grain yield and yield stability in nonirrigated, no-till fields. Results were not consistent or significant across the sites. Skip-row planting is expected to produce higher yields when growing season water is less than 26-27 inches, with conventional planting producing higher yields in wetter areas.
Project Support U.S. Agency for International Development to the International Sorghum and Millet Collaborative Research Support Program, Scholarship Secretariat, Government of Republic of Ghana
Project Website
Report Wortmann_Sorghum.pdf
Current Status Published Agron.J. 2010 102:296-302
Topic Crop Water Use and Water Use Efficiency
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 Agricultural Landuse Change Impacts on Bioenergy Production, Avifauna and Water Use in Nebraska's Rainwater Basin
Other(s) Daniel Uden, School of Natural Resources, daniel.uden@huskers.unl.edu; Rob Mitchell, USDA-ARS; Tim McCoy, Nebraska Game and Parks Wildlife Division; Qinfeng Guan, School of Natural Resources, qguan2@unl.edu 
Description

This study addressed how the conversion of marginally productive agricultural lands in the Rainwater Basin region of south-central Nebraska, U.S.A. to bioenergy switchgrass (Panicum virgatum) might impact ethanol production, grassland bird populations and agricultural groundwater withdrawals. This study also used multi-model inference to develop predictive models explaining annual variation in springtime wetland occurrence and flooded area in the Rainwater Basin.

Results suggest that cellulosic ethanol production from switchgrass and residual maize (Zea mays) stover within existing starch-based ethanol plant service areas is feasible at current feedstock yields, removal rates and bioconversion efficiencies. Throughout the Rainwater Basin, the replacement of marginally productive rowcrop fields with switchgrass could increase ethanol production, conserve groundwater and benefit grassland birds under novel future climatic conditions. However, converting Conservation Reserve Program (CRP) grasslands to switchgrass could be detrimental to grassland bird populations. Predictive wetland inundation models suggest that surrounding agricultural landuse, wetland hydric footprint shape complexity, and autumn and winter precipitation and temperature are strong drivers of springtime wetland occurrence and flooded area in the Rainwater Basin.

Under a modest change scenario, 350 wells on rowcrop fields converted to switchgrass could cease groundwater pumping, conserving 52,064 acre-feet of water annually (2.6% of regional pumping capacity).

Under a extreme change scenario, 737 wells on rowcrop fields converted to switchgrass could cease groundwater pumping, conserving 112,827 acre-feet of water annually (5.6% of regional pumping capacity).

In areas at higher risk for additional irrigation limitations, agriculture groundwater use under the modest change and extreme change scenarios could decrease by 9.6% and 19.1%, respectively.

Click here to read a journal article about this research

Project Support U.S. Geological Survey, Great Plains Landscape Conservation Cooperative
Project Website http://snr.unl.edu/aboutus/who/people/graduatestudent-member.asp?pid=1373#tab1
Report Uden Landuse Change.pdf
Current Status Completed
Topic Drought
Project's Primary Contact Information
Name Knutson, Cody
Unit National Drought Mitigation Center
Email cknutson1@unl.edu
Phone 402-472-6718
Web Page http://snr.unl.edu/aboutus/who/people/faculty-member.asp?pid=430
Project Information
Title Republican River Basin Water and Drought Portal
Other(s) Mark Svoboda, NDMC, msvoboda2@unl.edu; Donna Woudenberg, NDMC, dwoudenberg2@unl.edu; Jae Ryu, jryu@uidaho.edu 
Description The National Drought Mitigation Center (NDMC) is developing a decision-support web portal for the Republican River Basin in Nebraska, Colorado and Kansas, with support from the managers and staff of the Lower, Middle and Upper Republican Natural Resources Districts (NRDs) in Nebraska. Under the terms of the two-year grant, the NDMC will collaborate with the NRDs to identify and compile local drought monitoring and planning information needed by resource managers in the basin, including government agencies, local community planners, and agricultural producers, and package it into a web portal. The portal will eventually be housed on the websites of the NRDs and can serve as a model for developing local applications of the National Integrated Drought Information System.
Project Support National Oceanic and Atmospheric Administration - Sectoral Applications Research Program
Project Website http://www.rrbdp.org
Report
Current Status Underway
Topic Economics
Project's Primary Contact Information
Name Schoengold, Karina
Unit Department of Agricultural Economics
Email kschoengold2@unl.edu
Phone 402-472-2304
Web Page http://snr.unl.edu/aboutus/who/people/faculty-member.asp?pid=731
Project Information
Title Analysis of Potential Groundwater Trading Programs for Nebraska
Description

The goals of a recently funded project to measure the potential benefits of developing a groundwater trading market in Nebraska is discussed in this Cornhusker Economics article. Groundwater is a major component of agricultural water use. In extensive regions of the Western United States, rural agricultural economies rely entirely on groundwater. At the same time as providing water for human needs, groundwater is also an input to streams, wetlands and riparian areas that provide important ecosystem services. Ongoing groundwater pumping will deplete flows in adjacent streams, leading to potential conflict between human and environmental uses of water. In the last decades, many conflicts over transboundary allocations of water, endangered species and instream and riparian habitat have been driven by surface water-groundwater interaction. For example, claims have been filed with the United States Supreme Court over the impacts of groundwater use on flows of transboundary rivers for the Pecos River (Texas vs. New Mexico), the Arkansas River (Kansas vs. Colorado) and the Republican River (Kansas vs. Nebraska and Colorado). Groundwater has typically been viewed as private property, and its use in agriculture is generally neither regulated nor quantified precisely. However, there is growing interest in moving to systems that regulate groundwater use. The ability to trade groundwater allocations is often a part of such conversations.

Project Support National Science Foundation; USDA
Project Website
Report Groundwater_Trading_Nebraska.pdf
Current Status Underway
Topic Extension
Project's Primary Contact Information
Name Kranz, Bill
Unit Northeast Research and Extension Center
Email wkranz1@unl.edu
Phone 402-584-3857
Web Page http://bse.unl.edu/web/bse/wkranz1
Project Information
Title Demonstration Projects and Field Tours
Other(s) Charles Shapiro, Northeast Research and Extension Center, cshapiro1@unl.edu. 
Description

A project associated with using beef manure compost on sandy soils is being conducted near Pierce and Plainview as a means of improving soil quality, using a beef production by-product in crop production and reducing commercial fertilizer application. The data collected at these two sites has been presented by Charles Shapiro at several educational meetings across northeast Nebraska. The project shows a slight improvement is some parameters, but the cost of transportation reduces the quantity of compost that can be transported and so the effect on soil physical properties is minimal, although soil phosphorus levels are increasing.

Near Pierce a project funded by the Lower Elkhorn Natural Resources District aims to demonstrate the impact of reducing season long water application by 10% on corn yield. At this site the farmer uses a computer control panel to speed up or slow down his center pivot automatically to apply 10% less or 10% more than his normal application, respectively. Nitrogen is being applied at three different rates to demonstrate the adequacy of the UNL Calculation Procedure.

Near Brunswick a project funded by the Upper Elkhorn Natural Resources District aims to develop improved nitrogen credit following soybeans in a corn-soybean rotation. Six nitrogen treatments and 6 different cropping sequences have been imposed to determine the nitrogen credit from soybeans on sandy soils. This project will run through the 2008 growing season. To date data suggests lower nitrogen credits on the sands than the silt loam soils in eastern Nebraska.

Project Support Lower Elkhorn Natural Resources District, Upper Elkhorn Natural Resources District
Project Website
Report
Current Status Continuous
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 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 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 Big and Little Blue River Basins
Other(s) Cheng Cheng, School of Natural Resources, ccheng2@unl.edu 
Description Over extraction of groundwater near a stream can lower stream stage and induce streamflow depletion when the stream and aquifer are hydrologically connected. The Little Blue River Basin is an area of intensive groundwater development for irrigation, and the streamflow depletion in this basin was determined by an analog model (Emery, 1966). However, the post audit of the model (Alley and Emery, 1986) suggested that the decline of water-levels was overestimated and streamflow depletion was underestimated. Therefore, it is necessary to re-evaluate stream-aquifer interactions in the basin. In this study, an area is chosen for this analysis from the basin and three main streams -- the Little Blue River, Big Sandy Creek, and Spring Creek are included. Channel sediments and structures play an important role in determining stream-aquifer interactions. Firstly, field and laboratory methods including geoprobe logging and permeameter tests are utilized to investigate the channel deposits in the three main streams in the Little Blue River Basin. Results show that channels have low hydraulic-permeable layers which reduce their hydraulic connections to the adjacent aquifers. Secondly, a groundwater flow model is constructed to identify the hydraulic properties of the aquifer and evaluate streamflow depletion under groundwater withdrawals in the study area. Modeling results indicate that streamflow depletion is very low and aquifer storage loss is the main source of groundwater pumpage.
Project Support Upper Big Blue Natural Resources Distrect, Lower Big Blue Natural Resources District, Little Blue Natural Resources District
Project Website
Report
Current Status Completed
Topic Hydrology
Project's Primary Contact Information
Name Cheng, Cheng
Unit School of Natural Resources
Email ccheng2@unl.edu
Phone 402-472 0772
Web Page http://snr.unl.edu/aboutus/who/people/graduatestudent-member.asp?pid=798
Project Information
Title Statistical Distribution of Streambed Vertical Hydraulic Conductivity along the Platte River, Nebraska
Other(s) Xun-Hong Chen, School of Natural Resources, xchen2@unl.edu, Jinxi Song, Deming Wang 
Description Streambed vertical hydraulic conductivity (Kv) plays an important role in understanding and quantifying the stream-aquifer interactions. While several researchers have discussed the spatial variability of streambed horizontal hydraulic conductivity or Kv at one or several close-located sites in a river, they did not develop any statistical distribution analysis of streambed Kv at distant sites along a large river. In this paper, the statistical distribution and spatial variation of streambed Kv at 18 test sites in a 300-km reach of the Platte River in Nebraska are presented. Insitu permeameter tests using the falling-head method were carried out to calculate the streambed Kv values. Fine-grained sediments transported by two tributaries, the Loup River and the Elkhorn River, to the Platte River appear to result in lower streambed Kv values downstream of the confluences between the Platte River and the tributaries. The streambed Kv values were found to be normally distributed at nearly each test site. When the correlated Kv values were eliminated from the grid sampling plots, the remaining independent sub-datasets of streambed Kv values were still in normal distribution at each test site. Furthermore, the combined streambed Kv values upstream of the first confluence between the Platte River and the Loup River was normally distributed, which may be due to the lack of tributaries in-between and thus streambed sediments were well distributed in this reach and belonged to a single population of hydraulic conductivity values. In contrast, the combined dataset of all measurements conducted downstream of this confluence was no longer in normal distribution, presumably as a result of the mixing of different sediment sources.
Project Support Lower Platte North Natural Resources District, Program for Changjiang Scholars and Innovative Research Team in University of Ministry of Education of China
Project Website
Report Cheng_Distribution.pdf
Current Status Published in Water Resources Management DOI 10.1007/s11269-010-9698-5
Topic Hydrology
Project's Primary Contact Information
Name Eisenhauer, Dean
Unit Biological Systems Engineering
Email deisenhauer1@unl.edu
Phone 402-472-1637
Web Page http://bse.unl.edu/eisenhauer1
Project Information
Title Impacts of Land Terracing and Small Ponds on Basin Water Supplies
Other(s) Jim Koelliker, Biological and Agricultural Engineering, Kansas State University, koellik@ksu.edu; Derrel Martin, Biological Systems Engineering, dmartin2@unl.edu; Phil Barnes, Biological and Agricultural Engineering, Kansas State University, lbarnes@ksu.edu; Ayse Kilic, School of Natural Resources, akilic@unl.edu 
Description

Terraces in the Republican River Basin total about 2 million acres; about 15% of the basin above Hardy, Nebraska is terraced. The goal of this project is to better understand how on-farm conservation practices, specifically terraces and small ponds, affect the basin's water supplies. Data has been collected at five dryland fields near Culbertson, Curtis, and Stamford, Nebraska and Colby and Norton, Kansas. The Kansas sites are in areas where three main tributaries of the Republican River - Beaver, Sappa, and Prairie Dog creeks - flow toward Harlan County Reservoir. The field data collected will be used to determine if computer models created for the Republican River Basin accurately measure the impact of conservation terraces and small reservoirs on the basin.

Initial research results show:

  • About 16% of land in the Republican Basin is protected by terraces, and an equal number by small reservoirs
  • About 45% of runoff into a terrace channel goes to evapotranspiration (ET), 45% goes to groundwater recharge, and 10% overtops the terraces
  • Small reservoirs retain about 90% of inflow, most of which goes to groundwater recharge - little evaporation
  • Much overland flow is loss in transmission as recharge or ET from plants in the creek

Integrated values for the basin be completed by the end of 2010. For more information, see the following slides presented at the 2010 Greater Platte Basins Symposium:

Project Support U.S. Bureau of Reclamation
Project Website http://watercenter.unl.edu/PRS/PRS2010/Presentations/Eisenhauer%20Dean.pdf
Report
Current Status Continuing
Topic Hydrology
Project's Primary Contact Information
Name Harvey, F. Edwin
Unit School of Natural Resources
Email feharvey1@unl.edu
Phone 402-472-8237
Web Page http://eas.unl.edu/people/faculty_page.php?lastname=Harvey&firstname=Ed&type=ADJ
Project Information
Title Hydrologic Research in the Rainwater Basin Wetlands of South-Central Nebraska
Description

As part of this project, Harvey and his students are conducting research to unravel the hydrology of central Nebraska's Rainwater Basin wetlands. These wetlands are of international importance as habitat for millions of migratory water birds. In addition, these playa wetlands may contribute to groundwater recharge and water quality improvement. However, many of the wetlands have been drained, and those remaining suffer functional impairment due to sedimentation and pesticide and fertilizer runoff.

Most of the remaining Rainwater Basin wetlands are geographically isolated. Currently research is underway to investigate the role of these wetlands in providing groundwater recharge and water quality improvement. This is a significant environmental issue of concern because groundwater in this region is of vital importance, providing drinking and irrigation water. Moreover, groundwater levels are declining throughout much of the region. Levels of nitrate and atrazine exceed drinking water standards in some parts of the basin. Most of the remaining playa wetlands are impaired by sediment and there is an active program to restore the wetlands by removing this sediment. Study sites are located in Phelps, Kearney, Clay, Fillmore, and York counties (see map below).

Three components need to be measured when establishing a hydrologic budget for these closed basin wetlands which are surface storage, evapotranspiration (ET), and groundwater recharge. ET is calculated by the Bowen-Ratio Energy Budget (BREB) Method with the aid of a Bower Tower. Surface storage and recharge data will be aided by stilling wells and drive-point wells, respectively. Hydroperiods and plant community diversity are being determined before and after sediment removal to evaluate the impact of in-washed sediments on recharge and underlying groundwater quality. Chloride concentrations obtained from upland runoff collectors will be incorporated into the Chloride Mass-Balance Method along with precipitation and sediment chloride concentrations to obtain recharge fluxes for a wetland site.

Two Master's theses and one Bachelor's thesis have been completed as part of this project:

  • Wilson, Richard D. (2010), Evaluating Hydroperiod Response in the Rainwater Basin Wetlands of South-Central Nebraska, MS Thesis, UNL School of Natural Resources, 163 p.
  • Foster, Sarah E., (2010), Temporal and Spatial Variations of Ions, Isotopes and Agricultural Contaminants in Surface Waters and Groundwater of Nebraska’s Rainwater Basin Wetland Region, MS Thesis, UNL Department of Earth and Atmospheric Sciences, 185 p.
Project Support U.S. Environmental Protection Agency
Project Website http://snr.unl.edu/harvey/projectrainwater.htm
Report
Current Status Continuing
Pic 1 Project Image
Pic Caption 1 The Rainwater Basin area of Nebraska. 
Topic Hydrology
Project's Primary Contact Information
Name Woldt, Wayne
Unit Southeast Research and Extension Center
Email wwoldt1@unl.edu
Phone 402-472-8656
Web Page http://bse.unl.edu/wwoldt1
Project Information
Title Watershed Modeling System
Description Due to the highly connected nature of the water resources in the Republican River region, the significant increase in groundwater utilization for irrigation is suspected of inducing changes to the surface water system. These changes are exacerbated by drought conditions. Therefore, a greater understanding of the complex surface-groundwater system is very important for better management of water resources in the area. This project involves developing a watershed modeling system capable of simulating subsurface, overland, and stream flow in a fully integrated manner. This model considers various hydrogeological properties and therefore provides a more real picture of groundwater and surface water flow patterns and connections in the region. (This modeling system is different than traditional models such as ModFlow.) The objective of the research is to study the interaction processes of groundwater and surface water flow. The second objective is to progress toward simulating large-scale watersheds and significant amounts of data with increased time efficiency.
Project Support n/a
Project Website
Report
Current Status Underway
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 Invasive Species
Project's Primary Contact Information
Name Huddle, Julie
Unit School of Natural Resources
Email jhuddle2@unl.edu
Phone 402-472-8556
Web Page http://snr.unl.edu/vitae/faculty/2011/huddle-julie-cv-11012010.pdf
Project Information
Title Effects of eastern redcedar on the hydrology of cottonwood stands in the Republican River Basin
Other(s) Tala Awada, School of Natural Resources, tawada2@unl.edu, Derrel Martin, Biological Systems Engineering, dmartin1@unl.edu, Xinhua Zhou, School of Natural Resources, xzhou3@kumc.edu, Sue Ellen Pegg, School of Natural Resources, spegg2@unl.edu, Scott Josiah, Nebraska Forest Service, sjosiah2@unl.edu 
Description

This study examines how much water trees use in different forests. In riparian forests, invasive plants affect the quantity of water infiltrating and running off land by intercepting water and transpiring water. Sap flow sensors are being used to monitor how removal of invasive tree species affects tree-level and stand-level evapotranspiration. In addition, vegetation transects will reveal how understory plants respond to invasive tree removal. Researchers are gathering data using eddy covariance towers and satellite images. Study results will be used to test whether removing eastern Red Cedar and Russian Olive Trees can significantly improve water yields.

In regards to the understory response following the removal of invasive woody species from a cottonwood riparian forest, this research shows that:

  • Removing invasive species increased the frequency of invasive form and warm season grasses.
  • Species diversity increased when invasive tree species were removed.
  • Changes in understory species following thinning were most pronounced where eastern redcedars were removed.
  • Light level differences observed under different canopy types likely explain differences in understory species response to thinning. This will be examined in future studies.
Project Support Burlington Northern Endowment, Nebraska Department of Natural Resources, Nebraska Natural Resources Districts in the Republican River Valley, Southwest Nebraska Resource Conservation and Development (RCandD) Council Inc., Nebraska Southwest Weed Management Area
Project Website
Report Photographs of Understory.pdf
Current Status Published in the Great Plains Research 2011 21: 49-71
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 Riparian Vegetation Water Use
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 Riparian Vegetation Impacts on Water Quantity, Quality, and Stream Ecology
Other(s) Kyle Herrman, University of Wisconsin - Stevens Point, Kyle.Herrman@uwsp.edu; 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

The State of Nebraska is attempting to aggressively manage invasive species along the riparian corridors of the Platte River and the Republican River. Although the impetus for the removal is different, in both basins state agencies and weed management districts are using herbicides and mechanical removal to control a combination of invasive species led by Phragmites australis (common reed), Tamarix ramosissima Ledeb. (saltcedar), and Elaeagnus angustifolia L. (Russian olive).

Along the central stretch of the Platte River, invasive species have overtaken sandbars and side channels which are invaluable wildlife habitat. In an attempt to reclaim this habitat for bird species such as the Piping Plover and Whooping Crane, the state is removing large stretches of common reed. Along the Republican River, the state is removing all invasive species to reduce riparian evapotranspiration. By reducing evapotranspiration the hope is to increase stream flow along the Republican River. Since 2007 invasive species along the mainstem of the river and along the banks of the Harlan Reservoir have been sprayed with herbicide or mechanically removed.

In order to understand the impacts of removing invasive species along riparian corridors researchers at the University of Nebraska-Lincoln and collaborators at other universities have developed a multi-faceted research project.

On the Republican River basin researchers are directly measuring evapotranspiration rates from native and invasive plants. Researchers are also using a regional water balance model to estimate the water savings that could be achieved by removing all invasive species within the basin.

On the Platte River researchers are monitoring water quality changes associated with a controlled herbicide treatment of common reed. Using a combination of in situ instruments and grab samplers researchers are determining the impacts of species removal. Other experiments are being conducted to measure how invasive species alter biogeochemical processes and sediment characterization.

Visit the project website for more information, including real-time meteorological data from a riparian wetland near the Republican River, real-time water quality data at a stream site on the Platte River, and quarterly project reports.

Project Support Nebraska Environmental Trust, University of Nebraska Rural Initiative, University of Nebraska Institute of Agriculture and Natural Resources
Project Website http://www.geosciences.unl.edu/riparian/
Report
Current Status

Final Report on Riparian Vegetation Impacts on Water Quantity, Quality, and Stream Ecology

Topic Riparian Vegetation Water Use
Project's Primary Contact Information
Name Martin, Derrel
Unit Biological Systems Engineering
Email dmartin2@unl.edu
Phone 402-472-1586
Web Page http://bse.unl.edu/faculty/Martin.shtml
Project Information
Title Estimation of Evapotranspiration from Riparian and Invasive Species Using Remote Sensing and in Situ Measurements in the Republican River Basin
Other(s) Ayse Kilic, School of Natural Resources, akilic@unl.edu; Suat Irmak, Biological Systems Engineering, sirmak2@unl.edu; Shashi Verma, School of Natural Resources, sverma1@unl.edu; Tala Awada, School of Natural Resources, tawada2@unl.edu 
Description

This study is using a combination of techniques including remote sensing, to develop reliable estimates of evapotranspiration from riparian zones and determine varying water use rates for typical and invasive species in the Republican River Basin. The project will provide datasets of evapotranspiration and the annual water balance for a range of conditions in the riparian areas along the Republican River. Specific deliverables of the project include:

  • Map of surface energy fluxes, including evapotranspiration, across three watersheds in the Lower, Middle and Upper Republican Natural Resources Districts for different spatial and temporal (i.e. daily, seasonal and annual) scales.
  • Map of riparian vegetation classification across three watersheds using high resolution remote-sensing and ground truth observations.
  • Comparison of water use and water availability on riparian vegetation and adjacent treated research area by measuring evapotranspiration rates, using various methods.
  • Data for planners and decision-makers to develop water management policies.
  • Extension and education materials to inform and communicate results to stakeholders.
Project Support Nebraska Department of Natural Resources
Project Website
Report
Current Status Underway
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 Wastewater
Project's Primary Contact Information
Name Bartelt-Hunt, Shannon
Unit Civil Engineering
Email sbartelt2@unl.edu
Phone 402-554-3868
Web Page http://www.engineering.unl.edu/civil/faculty/ShannonBartelt-Hunt.shtml
Project Information
Title The occurrence of illicit and therapeutic pharmaceuticals in wastewater effluent and surface waters in Nebraska
Other(s) Daniel D. Snow, School of Natural Resources, dsnow1@unl.edu; Teyona Damon; Johnette Shockley; Kyle Hoagland, School of Natural Resources, khoagland1@unl.edu 
Description The occurrence and estimated concentration of twenty illicit and therapeutic pharmaceuticals and metabolites in surface waters influenced by wastewater treatment plant (WWTP) discharge and in wastewater effluents in Nebraska were determined using Polar Organic Chemical Integrative Samplers (POCIS). Samplers were installed in rivers upstream and downstream of treated WWTP discharge at Lincoln, Grand Island, and Columbus, downstream of Hastings' WWTP discharge, and from Omaha's effluent channel just prior to it being discharged into the Missouri River. Based on differences in estimated concentrations determined from pharmaceuticals recovered from POCIS, WWTP effluent was found to be a significant source of pharmaceutical loading to the receiving waters. Effluents from WWTPs with trickling filters or trickling filters in parallel with activated sludge resulted in the highest observed in-stream pharmaceutical concentrations. Azithromycin, caffeine, 1,7 - dimethylzanthine, carbamazepine, cotinine, DEET, diphenhydramine, and sulfamethazine were detected at all locations. Methamphetamine, an illicit pharmaceutical, was detected at all but one of the sampling locations, representing only the second report of methamphetamine detected in WWTP effluent and in streams impacted by WWTP effluent.
Project Support n/a
Project Website
Report Bartelt-Hunt_Wastewater.pdf
Current Status Published in Environmental Pollution 2009 157:786-791
Topic Wastewater
Project's Primary Contact Information
Name Woldt, Wayne
Unit Southeast Research and Extension Center
Email wwoldt1@unl.edu
Phone 402-472-8656
Web Page http://bse.unl.edu/wwoldt1
Project Information
Title Onsite Wastewater Treatment System Certification Training and Education Project
Other(s) Jan Hyngstrom, Biological Systems Engineering, jhygnstrom1@unl.edu; Sharon Skipton, Southeast Research and Extension Center, sskipton1@unl.edu 
Description

The goal of this project is to enable onsite wastewater treatment system professionals to apply science-based onsite wastewater design, installation, and maintenance practices and thereby protect water resources and human health. As of December 31, 2005, onsite professionals must pass exams to be certified pumpers, installers, and/or inspectors in the state of Nebraska. In-depth curriculum for Nebraska onsite wastewater system installers, inspectors and pumpers was developed to address this issue. The curriculum helps individuals prepare for exams, as well as help professionals apply science-based practices to protect water resources.

During 2005 and 2006, UNL Extension had 733 educational training contacts. Knowledge and competency was demonstrated by 86 percent passing their exam(s). Results from a follow-up survey of 460 of those who had attended training indicated pumpers (90%), installers (99%) and inspectors (100%) increased knowledge. Pumpers (76%), installers (71%), and inspectors (90%) reported they had made practices changes which would result in water quality and human health being better protected.

Certification training continues on an annual basis and new curriculum is being developed for advanced alternative treatment systems. These systems can achieve greater water quality protection in vulnerable areas including those with high groundwater levels and/or sandy soils. Merrick, Hall, and Hamilton Counties have geographic areas of high risk from traditional onsite wastewater treatment systems due to these factors. Alternative systems could greatly reduce the risk of water quality degradation from nitrate and other contaminants in these areas.

Educational materials have also been developed and delivered for homeowners with onsite systems. The goal is to empower rural homeowners to protect water resources and human health through application of science-based onsite system maintenance and operation practices. Training was delivered in Grand Island and to 50 residents with onsite systems at Turtle Beach near Central City.

Project Support Nebraska Department of Environmental Quality, Nebraska Onsite Waste Water Association
Project Website http://water.unl.edu/web/sewage/home
Report
Current Status Continuous
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 Dvorak, Bruce
Unit Civil Engineering
Email bdvorak1@unl.edu
Phone 402-472-3431
Web Page http://www.engineering.unl.edu/civil/faculty/BruceDvorak.shtml
Project Information
Title Arsenic and Uranium in Drinking Water Training and Education Project
Other(s) Wayne Woldt, Biological Systems Engineering, wwoldt1@unl.edu; Sharon Skipton, Southeast Research and Extension Center, sskipton1@unl.edu; Gina Rust 
Description

When new Environmental Protection Agency Safe Drinking Water Act standards for arsenic and uranium were enacted, 82 Nebraska public water supplies had arsenic concentrations above the maximum level allowed and 20 had uranium above the standard, including public water supplies in Hamilton, Hall, and Merrick counties. Since arsenic and uranium are naturally occurring in rocks and soil, private water supplies in these geographic areas could also be at risk of having elevated concentrations, possibly putting families at risk from chronic exposure.

A UNL Extension team with a drinking water focus developed and delivered training to UNL Extension faculty/staff in targeted areas at high risk for naturally occurring arsenic and/or uranium. Twelve training sessions were delivered in 2005 including training in Merrick and Hall Counties. Thirty-nine extension personnel with a focus or job description other than drinking water were trained, including 3 in Hall County and 3 in Merrick County. Participants increased their knowledge of the topic in order to work better with owners of private drinking-water wells in the high risk areas. Of those returning an evaluation, 92% strongly agreed or agreed their knowledge increased in regard to arsenic and uranium occurrence, risk, testing, and treatment. These faculty and staff have gone on to provide information and education at the local level to private well owners.

Training on arsenic and uranium in drinking water was delivered at the Nebraska Well Drillers Winter Short Course in 2006 and information on arsenic in drinking water was presented in 2007. Nearly 300 water well professionals attended in 2006 and approximately 250 attended in 2007. Seven percent of 2006 participants evaluating the program indicated the arsenic and uranium program was the best topic during the event, and 19% indicated they were interested in learning more about the topic. Participants indicated they would use the information gained to "spread knowledge on arsenic and uranium to pivot system owners," "educate/inform constituents, customers," "expand markets in arsenic and uranium testing," or "provide safer water."

UNL Extension also delivered training on arsenic and uranium in drinking water at a Professionals Seminar in 2006. Thirty-eight professionals attended. Several professionals involved stated that the focused three-hour presentation gave them an excellent overview of the pertinent design issues which communities and engineers should consider when selecting a method of dealing with high arsenic and uranium levels. They especially appreciated the mix of technical presentations with a panel discussion by community members, regulators, and local engineers.

Project Support Well Driller Training - Nebraska Well Drillers Association Professional Seminar - Nebraska Section of the American Water Works Association, Nebraska Health and Human Services System
Project Website
Report
Current Status Completed
Topic Water Quality
Project's Primary Contact Information
Name Riens, John
Unit Wisconsin Ecological Services Field Office, U.S. Fish & Wildlife Service
Email John_Riens@fws.gov
Phone 541-885-2503
Web Page http://www.fws.gov/
Project Information
Title Macroinvertebrate Response to Buffer Zone Quality in the Rainwater Basin Wetlands of Nebraska
Other(s) W. Wyatt Hoback, Biology UNK, hobackww@unk.edu; Matt Schwarz, U.S. Fish & Wildlife Service 
Description

The Rainwater Basin is one of the most endangered wetland ecosystems in North America. This ecosystem is critical to many species including migratory waterfowl. Land use and runnoff from agriculture and cattle confinement operations are likely to be reducing the basin's health and diversity, however little information exists concerning macroinvertebrates. Twenty-two locations were assessed for water quality parameters, vegetation composition, and macroinvertebrates identified to genus. Samples were collected biweekly starting in April through July for three years. Macroinvertebrate diversity was impacted in areas with little buffer although the effects were not pronounced. Institution of a more effective vegetative buffers strip may reverse this trend to improve ecosystem quality and provide for invertebrate resources for migratory birds.

Click here to see a poster about this research

Project Support n/a
Project Website
Report
Current Status Completed
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 Watershed Management
Project's Primary Contact Information
Name Knutson, Cody (advisor)
Unit National Drought Mitigation Center
Email cknutson1@unl.edu
Phone 402-472-6718
Web Page http://snr.unl.edu/aboutus/who/people/faculty-member.asp?pid=430
Project Information
Title Stakeholder Perceptions of Water Supply Management and Sustainability in the Republican River Basin in Nebraska
Other(s) Ryan Bjerke, ryan.bjerke@huskers.unl.edu 
Description Due to a variety of human-induced and natural factors, water resources throughout the world will continue to face mounting challenges to their longevity and extent, and those within the Republican River Basin in Nebraska are no exception. Understanding the perspectives of water users is essential for developing informed and effective water resource policies and management plans. This study utilized a key informant sampling strategy in conjunction with in-depth telephone interviews to ascertain the perceptions of 32 key stakeholders in the Republican River Basin in Nebraska on concepts pertaining to water supply management and sustainability. The interview questionnaire was designed using a mixed methods approach that relied on qualitative and quantitative measures. Specifically, stakeholders were asked a series of questions to understand their perspectives on: the causes of water supply stress in the basin; what sustainable water management meant to them; the sustainability of water resources in the basin; and solutions that could be implemented to reduce water supply stress in the basin (e.g., financial, regulatory, infrastructure development, and water conservation and technical options). The study found a majority of individuals attributed ground water level declines to increased ground water use, more ground water users, and changing climate, while most believed surface water flow reductions were due to these factors in addition to soil and water conservation measures and increased near- and in-channel plant growth. Because of the need to maintain economic viability and protect water for future generations, water resource sustainability was very important to participants. Stakeholders thought solutions to water resources issues could be best achieved by employing a combination of: regulatory measures, like irrigated acreage and pumping limits; water conservation options, such as crop rotations and conservation tillage; and technological advancements, like more water-efficient irrigation systems and improved hybrids. Overall, eliciting stakeholder's perceptions on issues related to water supply stress and sustainability, along with potential solutions, may help inform policy and management decisions aimed at promoting water resource sustainability in the basin.
Project Support
Project Website
Report
Current Status Graduate thesis project completed December 2009 - thesis available at UNL CY Thompson Library (Call # LD3656 2009 .B547)
Topic Wetlands
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 Developing LiDAR-Derived Wetland Maps To Assess Conservation Design Practices For Playa Wetlands In Rainwater Basin
Other(s) Ed Harvey, School of Natural Resources, feharvey1@unl.edu; Xu Li, Department of Civil Engineering 
Description The overall goal of this project is to provide wetland managers with topographically-correct 3-D wetland maps to prioritize wetland conservation efforts and assess wetland conservation design practices. This project addresses three specific tasks for the playa wetlands: 1) Establish accurate, topographically-correct, 3-D wetland maps to relate weather conditions and wetland functions; 2) Develop a measurable Restorable Wetland Index to prioritize playa wetland and drainages conservation; 3) Assess wetland conservation design practices for watershed-based wetland conservation. This research will use high-resolution Light Detections And Ranging (LiDAR) data to create next-generation wetland maps for playa wetlands. The research provides the missing link in conservation design as these data will provide accurate elevation measures to delineate watershed extent and determine the impact of individual hydrologic modifications. This project will be one of the first to integrate LiDAR data and a hydrologic modifications datasets to find the relations of current weather conditions and wetland functions. This project provides reliable, accurate wetland spatial parameters to prioritize playa wetland conservation and assess the effectiveness of existing wetland conservation design practices. The wetland conservation design tools and protocols will be examined in two pilot counties in Nebraska. The intellectual merit of the research is based on advancing knowledge linkage of wetland mapping technologies and wetland function modifications, and showing how to adapt wetland conservation designs. The outputs from this project provide practical protocols for state/regional/local wetland managers and thus ensure "no net loss" in quality and quantity of wetlands.
Project Support US EPA
Project Website
Report
Current Status Completed
Topic Wildlife
Project's Primary Contact Information
Name Allen, Craig
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 River Otter Home Range and Habitat Use
Other(s) Sam Wilson, School of Natural Resources, swilson5@yahoo.com; Amy Williams, School of Natural Resources, amy_ruth18@hotmail.com 
Description

River otters (Lontra canadensis) are native to Nebraska but were extirpated by the early 1900s. River otters became reestablished in Nebraska following their reintroduction in the mid 1980s and early 1990s by the Nebraska Game and Parks Commission. The species is currently listed as threatened in Nebraska. Despite the high profile of the reintroduction and the otters' role as a flagship species, relatively little is known about river otter ecology in Nebraska. In order to provide information for management, research was conducted to determine home range, habitat use, overnight movement distance, and annual survival of river otters in the central Platte River of Nebraska.

Eighteen river otters were trapped, implanted with telemetry transmitters, and tracked during 2006-2009. Researchers obtained 996 telemetry locations and constructed 13 annual home ranges. Male home ranges were larger than female home ranges. Habitat use was determined by comparing used versus available habitats using compositional analysis. Open water was used more than any other habitat type in all three comparisons tested.

Nineteen overnight movements were recorded (465 total telemetry locations) for four river otters during 2007-2008. Movements during January-February, when NGPC conducts winter bridge surveys, were lower than during the rest of the year. Annual survival was 100% as no river otter mortalities were detected during the study period.

River otters in the central Platte River select open water over other habitat types, exhibit reduced movements during winter months, and have high annual survival. This information will be used by NGPC to assess the status of river otters in Nebraska and direct management efforts for the species.

Project Support Nebraska Game and Parks Commission
Project Website n/a
Report Wilson River Otter.pdf
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
Location

Platte Valley WMA

Platte Valley WMA Web Site

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