NU Water-Related Research in District 37

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

Displaying 28 records found for District 37


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 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 Agronomy and Horticulture
Email kcassman1@unl.edu
Phone 402-472-5554
Web Page http://agronomy.unl.edu/cassman
Project Information
Title Real-time Decision Support System for Deficit Irrigation - Hybrid-Maize
Other(s)  
Description

Hybrid-Maize is a computer program that simulates the growth of a corn crop under non-limiting or water-limited (rainfed or irrigated) conditions based on daily weather data. Specifically, it allows the user to:

  • assess the overall site yield potential and its variability based on historical weather data
  • evaluate changes in attainable yield using different combinations of planting date, hybrid maturity, and plant density
  • explore options for optimal irrigation management
  • conduct in-season simulations to evaluate actual growth up to the current date based on real-time weather data, and to forecast final yield scenarios based on historical weather data for the remainder of the growing season

Hybrid-Maize does NOT allow assessment of different options for nutrient management nor does it account for yield losses due to weeds, insects, diseases, lodging, and other stresses. Hybrid-Maize has been evaluated primarily in rainfed and irrigated maize systems of the U.S. Corn Belt. Caution should be exercised when applying this model to other environments as this may require changes in some of the default model parameters.

This project will develop a similar tool for irrigation scheduling for Nebraska soybean producers, and a real-time decision support system for deficit irrigation on corn, both based upon the Hybrid-Maize model. These tools will assist producers who have limited irrigation water supplies to optimize irrigation scheduling in real time for maximum yields, in particular during water-short years.

Project Support Nebraska Natural Resources Conservation Service, Nebraska Soybean Board
Project Website http://hybridmaize.unl.edu/
Report
Current Status Continuing - Software Available
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 Irmak, Suat
Unit Biological Systems Engineering
Email sirmak2@unl.edu
Phone 402-472-4865
Web Page http://bse.unl.edu/sirmak2
Project Information
Title Nebraska Agricultural Water Management Demonstration Network
Other(s) Gary Zoubek, York County Extension, gzoubek@unl.edu 
Description

The Nebraska Agricultural Water Management Demonstration Network (NAWMDN) encourages the adoption of newer technologies that will enable farmers to use water and energy resources associated with irrigated crop production efficiently. NAWMDN launched in 2005 and started with 20 growers from south central Nebraska who joined the Network as collaborators. In 2008 an online tool named ETgage was added to enable participation by growers throughout Nebraska.

The NAWMDN ETgage project is one part of a system for testing cutting-edge technologies and creating a network with growers, UNL Extension, NRDs, NRCS, and crop consultants, and other interested partners, that will enable the adoption of water and energy conservation practices. The simplicity of the use and interpretation of the ETgage data, as well as its economic feasibility, makes it easy for farmers to monitor crop water use for effective irrigation management. In this project ETgages are used to estimate crop water use, and Watermark sensors are used to measure soil moisture to determine irrigation timing and amount. Each year, NAWMDN team members organize educational meetings during the growing season and over the winter to implement the project, teach participants how to use the ETgage and Watermark sensors for irrigation management, review the results, set goals, and obtain grower feedback. This project has been reported at local, regional, and national meetings.

In 2005, there were 18 demonstration sites. Some of the ETgage and Watermark sensors were read by growers and some were read weekly by Network core members. In 2006, the second year of the project, there were more than 50 demonstration sites. In 2007 more than 125 cooperators in nine NRDs and 22 counties were involved. In the fall of 2007, 89 producers involved in the NAWMDN were surveyed; of those 56% responding, the estimated corn water savings varied from 0-7.5" with an average savings of 2.6," while soybeans water savings varied from 0-4.8" with an average of 2.1." Using 2007 diesel prices, this resulted in total energy savings of $2,808,000 and $2,269,800 for corn or soybeans over 117,000 acres.

In 2008 over 300 active participants from 25 counties in 9 of Nebraska's 23 NRDs. An interactive web site was also created to inform growers and other clients about the network and to educate producers and industry professionals about using these two tools along with crop stage of growth information to make irrigation management decisions. This interactive web site has engaged the cooperating producers and enhanced learning. The site consists of a map of Nebraska's 93 counties on which producers can select specific counties to find a Google gps map with ETgauge locations marked. Producers can click on specific sites to see the weekly reference evapoptranspiration (ET) reported by producers. The site also includes information about the NAWMDN and how to use the various tools.

For detailed information, see Nebraska Agricultural Water Management Demonstration Network: Integrating Research and Extension/Outreach.

Project Support Partners include personnel from 19 extension offices, the Little Blue NRD, the Upper Big Blue NRD, Nebraska Association of Resources Districts, Nebraska Natural Resources Conservation Service, South Central Agricultural Laboratory, and the Central Nebraska Public Power and Irrigation District.
Project Website http://water.unl.edu/cropswater/nawmdn
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 A Decision Support Tool to Increase Energy and Crop Water Use Efficiency for Corn and Soybean Production
Description

Energy costs coupled with limitations in water availability are threatening the sustainability of irrigation in the state. Energy costs for irrigation rose almost 100 percent for typical Nebraska irrigators from the spring of 2003 to the summer of 2006 and continue to rise sharply. The rising cost of fuel and the limited availability of water make producing maximum crop yield with minimal input imperative.

Nebraska growers need scientifically based and practical management strategies that can aid them in their decision-making process to enhance crop water-use efficiency and reduce energy use to achieve maximum profitability. Growers are looking for answers on how to make a maximum use of limited irrigation water and how to manage irrigation water to reduce pumping cost.

Crop simulation models with the capability of "real-time" assessment of crop and soil water status and yield prediction based on historical climate data represent a powerful new tool to help improve irrigation decisions and increase water-use efficiency especially for situations where the amount of available water supply is less than the full requirement for maximum crop yield. This project validates and demonstrates a decision-support tool for a real-time irrigation scheduling period, and releases the new tool as a software program for use by crop producers, crop consultants, and industry professionals. This tool will be used to assess energy requirement for different irrigation regimes to aid growers and state and federal agencies to make better-informed management decisions.

Project Support Upper Big Blue Natural Resources District, Gard Fund
Project Website
Report
Current Status Underway
Topic Crop Water Use
Project's Primary Contact Information
Name Martin, Derrel
Unit Biological Systems Engineering
Email dmartin1@unl.edu
Phone 402-472-1586
Web Page http://bse.unl.edu/dmartin2
Project Information
Title Enhancing Irrigation Management Tools and Developing a Decision System for Managing Limited Irrigation Supplies - Enhancing The Water Optimizer
Other(s) Chris Thompson, Agricultural Economics, cthompson2@unl.edu; Paul Burgener, Panhandle Research and Extension Center, pburgener2@unl.edu; Ray Supalla, Agricultural Economics, rsupalla1@unl.edu; Gary Hergert, Panhandle Research and Extension Center, ghergert1@unl.edu 
Description

The Water Optimizer is a computer model developed in response to several years of drought across the state and to farmers facing water restrictions. The model can be used by producers to evaluate management options when water is limiting due to drought or regulations; it can also be used by water planners or policy makers who wish to estimate the farm-level economic consequences of retiring acres or regulating the water supply. Released by UNL in 2005, the model is available for all counties in Nebraska to evaluate single fields for several crop options. Irrigated crops include: corn, soybeans, sorghum, wheat, alfalfa, edible beans and sunflowers. Dryland crops include: corn, soybeans, sorghum, sunflowers, alfalfa and wheat in continuous, summer fallow and eco-fallow rotations. Producers put information into a Microsoft Excel spreadsheet, including soil type and irrigation system options. Irrigation options include center pivot or gravity irrigation systems, well or canal delivery, and systems powered by electricity, diesel or natural gas. After entering this basic information, producers enter their production costs, irrigation costs, crop prices, crop type and available water. After these parameters have been set, the program calculates what crops will be most profitable with the given costs and available water. This gives the producer a "whole farm view" in considering how to manage available water supplies.

While the Water Optimizer is useful, it is limited in that it considers economic choices and consequences one field (well) and one year at a time. Three different departments (Agronomy-Horticulture, Agricultural Economics and Biological Systems Engineering) will combine their expertise to develop information to enhance Water Optimizer by: 1) improving the tool's function for crops grown in the semiarid High Plains, including canola, camelina, chickpeas, dry beans and sunflowers; 2) expanding the tool's geographic coverage area to additional counties in Nebraska including irrigated areas in Colorado and Kansas; 3) developing the capability to evaluate risk-management alternatives on a whole-farm basis as well as field by field; and 4) developing the capability to determine the best strategies for managing multi-year water allocations. The benefits of this project will be to maintain profitability and sustain farming enterprises with a limited irrigation supply. The goal is to conduct educational programming in conjunction with the project to encourage other producers to implement practices and concepts demonstrated in this project. An additional outcome will be transferring this information to other areas of declining ground water or surface water.

The Water Optimizer tool was developed to assist in addressing water shortages created by drought and interstate water rights litigation. The current model released November 2010, supports all 93 Nebraska counties.

Project Support U.S. Department of Agriculture Risk Management Agency
Project Website http://agecon.unl.edu/wateroptimizer
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 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 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 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
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 Monitoring, Mapping and Risk Assessment for Non-Indigenous Invasive Species in Nebraska
Other(s) Karie Decker, Nebraska Invasive Species Project Coordinator, invasives@unl.edu 
Description

Biological invasions are a growing threat to both human enterprise and ecological systems. This project provides resources to the public and private sector on: 1) the potential spread and impact of non-indigenous species in Nebraska; 2) actual and potential maps of non-indigenous species range (habitat specific maps at high resolution); 3) information regarding identification and management of potential invaders; 4) centralized information on management and impacts and potential spread of currently established non-indigenous species (a web portal); and 5) outreach within Nebraska to county-level governments and individual stakeholders regarding the management, surveillance and control of non-indigenous species. On February 7-8, 2008 a conference on non-indigenous species impacts, spread and management was held, focusing on state-of-our-knowledge and coordination of disparate management and information-provisioning efforts with a goal towards unification of disparate efforts.

This project is meant to build momentum towards a cohesive non-indigenous species biosecurity and management system in Nebraska that is integrated and relatively seamless across institutional boundaries. Spatially - based risk assessments that focus on non-indigenous invasive species impacts on at - risk native species and communities in Nebraska have been initiated with funding from the U.S. Geological Survey and the Nebraska Game and Parks Commission. The results and predictive models generated by this project will be delivered and made widely available to policy makers, management practitioners and landowners in Nebraska. Additional general information about potential invasive species and their impacts will be made easily accessible. Most of the goals listed above will produce and disseminate products that are dynamic, with interactive elements for the public and managers, including mapping of habitat-specific current and potential distributions of invasive species as well as a portal through which the public can inform the entities responsible for management of invasive species occurrence and spread - and vice versa.

Project Support U.S. Geological Survey, Nebraska Game and Parks Commission, Nebraska Environmental Trust
Project Website http://snr.unl.edu/invasives
Report
Current Status Continuing
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 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 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 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 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 Tang, Zhenghong
Unit Architecture
Email ztang2@unl.edu
Phone 402-472-9281
Web Page http://architecture.unl.edu/people/bios/tang_zhenghong.shtml
Project Information
Title Assessment of Sedimentation and Water Quality Conditions in the Rainwater Basin's Playa Wetlands
Other(s) Mark Kuzila, School of Natural Resources, mkuzila1@unl.edu; Xu Li, Department of Civil Engineering, xuli@unl.edu; Amy Burgin, School of Natural Resources, aburgin2@unl.edu 
Description

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

Three specific tasks are included in this project:

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

The final products of this project include:

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

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

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

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

Project Support n/a
Project Website
Report
Current Status Continuing
Topic Watershed Management
Project's Primary Contact Information
Name 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 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 Pope, Kevin
Unit Nebraska Cooperative Fish and Wildlife Research Unit
Email kpope2@unl.edu
Phone 402-472-7028
Web Page http://snr.unl.edu/aboutus/who/people/faculty-member.asp?pid=759
Project Information
Title Population Assessment of Channel Catfish in Nebraska
Other(s) Lindsey Chizinski, Graduate Assistant 
Description

Channel catfish (Ictalurus punctatus) is an important sport fish, particularly in the Great Plains. In Nebraska, a majority of anglers target channel catfish, and fishing activities are a vital part of the state’s economy. Lentic water bodies provide the primary fishing opportunity for catfish anglers in Nebraska. Despite the popularity and economic importance of channel catfish, little is known of its population dynamics or habitat requirements, and existing studies often profile river populations.

Current standards for sampling channel catfish in lentic systems often yield inadequate catch to assess populations. The objective of this study was to utilize a recently developed sampling method, tandem-set hoop nets, to collect channel catfish in sufficient quantities to describe the effects of stocking and habitat variability on populations in lentic ecosystems. Three lentic ecosystems common to the Great Plains were considered: sand pits, flood-control reservoirs, and irrigation/power-generation reservoirs.

The influence of stocking on abundance and condition of channel catfish varied with ecosystem type. In sand pits, stocking negatively influenced fish condition, and only stocking on an annual basis positively influenced abundance. In flood-control reservoirs, stocking did not influence fish condition, but was associated with greater abundance. In irrigation/power-generation reservoirs, stocking did not influence fish condition or abundance. Additionally, there was evidence that mortality and growth rates varied with ecosystem type. In general, channel catfish from irrigation/power-generation reservoirs were predicted to experience slower growth and lower mortality, whereas channel catfish from sand pits were predicted to experience the fastest growth and highest mortality.

Catch rates of channel catfish were substantially less in this study compared to previous records of tandem-set hoop net surveys, but hoop nets were more efficient than the current standard gear, experimental gill nets, at capturing channel catfish. That is, 100 channel catfish could be captured with fewer sets of hoop nets than gill nets. However, catch rates and size structure of channel catfish in tandem-set hoop nets varied within the sampling season and between years. Furthermore, length-frequency distributions of channel catfish were dissimilar between hoop nets and gill nets.

Click here to read Lindsey Chizinski's Master's Thesis on Channel Catfish Population in Nebraska

Project Support Nebraska Game and Parks Commission
Project Website http://snr.unl.edu/necoopunit/research.main.html#channel_catfish
Report
Current Status Completed
Topic Wildlife
Project's Primary Contact Information
Name Pope, Kevin (advisor)
Unit Nebraska Cooperative Fish and Wildlife Research Unit
Email kpope2@unl.edu
Phone 402-472-7028
Web Page http://snr.unl.edu/aboutus/who/people/faculty-member.asp?pid=759
Project Information
Title Impact of White Perch on Walleye and Predators of White Perch at Branched Oak and Pawnee Reservoirs
Other(s) Nathan Gosch, Graduate Research Assistant 
Description

Habitat alterations and accidental introduction of white perch into Branched Oak Lake have shifted the fish community from one dominated by littoral (near-shore) species (e.g., largemouth bass and bluegill) to one dominated by pelagic (open-water) species (e.g., white perch and gizzard shad). Along with the change in the fish community, angler trips to Branched Oak Reservoir have declined by 85% over the last two decades. Further, the white perch population has become stunted, meaning there is a high density of slow growing individuals that mature at a small size. Like Branched Oak Lake, Pawnee Lake historically supported an active and diverse fishery, and has experienced similar habitat alterations and accidental introduction of white perch; however, unlike Branched Oak Lake, stunting has not yet occurred for the white perch population in Pawnee Lake.

Studies at both lakes enable researchers to examine white perch interactions with other fishes in two similar Nebraska reservoirs having different white perch population stages (i.e., stunted and non-stunted). Food habits and diet overlap among white perch, crappie, walleye, white bass, and channel catfish are being evaluated. To study diet, fish stomachs are pumped and the contents analyzed to understand which fish species prey on white perch. All stomach content samples are analyzed and data synthesized. Stable isotope analyses of stomach contents have been conducted and the results confirmed.

By documenting the potential competition bottlenecks that exist between white perch and other fish species of importance, management program may be developed to eliminate stunted status for the white perch population in Branched Oak Lake and to prevent stunting of the white perch population in Pawnee Lake.

Project Support U.S. Geological Survey, Nebraska Game and Parks Commission
Project Website http://www.nlc.state.ne.us/epubs/U1500/B011-2008.pdf
Report
Current Status Completed - report available