Digital Commons Network^™

Cover Crop Mixtures For The Western Corn Belt: Opportunities For Increased Productivity And Stability, Samuel E. Wortman, Charles A. Francis, John L. Lindquist

Department of Agronomy and Horticulture: Faculty Publications

Achieving agronomic and environmental benefits associated with cover crops oft en depends on reliable establishment of a highly productive cover crop community. The objective of this study was to determine if cover crop mixtures can increase productivity and stability compared to single species cover crops, and to identify those components most active in contributing to or detracting from mixture productivity. A rainfed field experiment was conducted near Mead, Nebraska, United States, in 2010 and 2011. Eight individual cover crop species (in either the Brassicaceae [mustard] or Fabaceae [legume] family) and four mixtures of these species (two, four, six, and eight …

Limnological Assistance For Lake Mead National Recreation Area: Quarterly Report, Period Ending December 31, 2011, Margaret N. Rees

Limnological Studies

Project 1

• Technical assistance with the implementation of the Interagency Monitoring Action Plan (IMAP) for Quagga Mussels is ongoing; remaining analyses are underway with report delivery rescheduled for 05/2012.
• Data have been delivered for Veliger abundance and settlement at different depths of Lake Mead with report delivery re-scheduled for 05/2012.
• Growth of adult quagga mussels within Las Vegas Wash/Las Vegas Bay
• The Interagency Quagga Mussel Meeting was held on 11/17/2011; the next meeting is scheduled for 02/16/2011.

Project 2

• Appendix 7, an addition to the Long-term Limnological and Aquatic Resource Monitoring and Research Plan for Lakes Mead and Mohave, has …

Variability In Parasites’ Community Structure And Composition In Cat Fish With Respect To Level Of Pollution In Mwanza Gulf, Lake Victoria, Tanzania, C. J. Mwita

Tanzania Journal of Science

This study investigated the composition and structure of the parasite communities in Cat fish with respect to levels of water pollution in Lake Victoria. A total of 1071 Clarias gariepinus with mean TL range of 19 to 27 cm were analyzed from three localities in Mwanza Gulf (Kirumba, 298 fish infected with 15 parasite species), Nyegezi (376 fish, with 15 parasites species) and Malimbe (397 fish, with 16 parasites species). Trematodes and nematodes dominated the population with six (35.3%) and five (29.4%) species, respectively. Mean species richness and heteroxenous/monoxenous ratio showed significant changes (Fr = 8.000; p = 0.0046), being …

Science With A Skew: The Nuclear Power Industry After Chernobyl And Fukushima, Gayle Greene

Scripps Faculty Publications and Research

It is one of the marvels of our time that the nuclear industry managed to resurrect itself from its ruins at the end of the last century, when it crumbled under its costs, inefficiencies, and mega-accidents. Chernobyl released hundreds of times the radioactivity of the Hiroshima and Nagasaki bombs combined, contaminating more than 40% of Europe and the entire Northern Hemisphere. But along came the nuclear lobby to breathe new life into the industry, passing off as “clean” this energy source that polluted half the globe. The “fresh look at nuclear”—in the words of a New York Times makeover piece …

Efficacy Of A Novel Chelator For Mercury Chelation And Distribution, David Harold Clarke

Student Theses and Dissertations

Mercury is found throughout the environment with a distribution on a global scale in nearly all terrestrial to marine environments. Biotransformation of divalent mercury and subsequent bioaccumulation of organo-mercury species is catalyzed by sulfate reducing bacteria. Trophic transport of the resultant methyl mercury, a highly toxic species, leads to upward accumulation in the trophic structure of aquatic environments and ultimately to human exposure through consumption of methyl mercury laden fish. The potential for human health risk has made mercury a high priority environmental contaminant. Research aimed at assessing the within-organism fate of mercury using a genetically tractable mammalian model is …

Integrated Waste Management As A Climate Change Stabilization Wedge For The Maletese Islands, Clyde Falzon

Masters Theses, 2010-2019

Planet Earth is finding difficulty in dealing with the continuous increase in anthropogenic greenhouse gas emissions. This is leading to change in climate which leads to extensive damage to communities, ecosystems and resources. This study is focussed on the waste sector which is the second largest greenhouse gas emitter in the Maltese islands after the energy (including transport) sector. Moreover, if practiced according to standards, waste management can lead to emission reduction. This work is based on the stabilisation wedges strategy and specifically focused on the integrated waste management wedge. Moreover in this work a life cycle assessment methodology is …

The Examination Of The Feasibility Of Implementing A Biosphere Reserve In The Maltese Islands : Applying A Conservation Value Evaluation Framework, Alexander Borg

Masters Theses, 2010-2019

Biosphere reserves are protected areas which are internationally recognized within the United Nations Educational, Scientific and Cultural Organisation’s Man and the Biosphere Programme for promoting and establishing a balanced relationship between people and nature. Biosphere reserve management is guided by principles of biodiversity conservation; sustainable development; local, national and international partnership and support; local capacity-building; research and monitoring and co-operative management that is multidisciplinary, multi-stakeholder and locally-based. The research evaluated the feasibility of implementing the biosphere reserve concept in the Maltese Islands. This was studied by applying a conservation framework which consisted of holistic conservation value appraisal criteria – incorporating …

Model Comparisons For Estimating Carbon Emissions From North American Wildland Fire, Nancy H. F. French, Willam J. De Groot, Liza K. Jenkins, Brendan M. Rogers, Ernesto Alvarado, Brian Amiro, Bernardus De Jong, Scott Goetz, Elizabeth Hoy, Edward Hyer, Robert Keane, B. E. Law, Donald Mckenzie, Steven G. Mcnulty, Roger Ottmar, Diego R. Perez-Salicrup, James Randerson, Kevin M. Robertson, Merritt Turetsky

Michigan Tech Research Institute Publications

Research activities focused on estimating the direct emissions of carbon from wildland fires across North America are reviewed as part of the North American Carbon Program disturbance synthesis. A comparison of methods to estimate the loss of carbon from the terrestrial biosphere to the atmosphere from wildland fires is presented. Published studies on emissions from recent and historic time periods and five specific cases are summarized, and new emissions estimates are made using contemporary methods for a set of specific fire events. Results from as many as six terrestrial models are compared. We find that methods generally produce similar results …

Vulnerability Of High Latitude Soil Organic Carbon In North America To Disturbance, Guido Grosse, Jennifer Harden, Merritt Turetsky, David A. Mcguire, Philip Camill, Charles Tarnocai, Steve Frolking, Edward A.G. Schuur, Torre Jorgenson, Sergei Marchenko, Vladimir Romanovsky, Kimberly P. Wickland, Nancy H. F. French, Mark Waldrop, Laura Bourgeau-Chavez, Robert G. Striegl

Michigan Tech Research Institute Publications

This synthesis addresses the vulnerability of the North American high-latitude soil organic carbon (SOC) pool to climate change. Disturbances caused by climate warming in arctic, subarctic, and boreal environments can result in significant redistribution of C among major reservoirs with potential global impacts. We divide the current northern high-latitude SOC pools into (1) near-surface soils where SOC is affected by seasonal freeze-thaw processes and changes in moisture status, and (2) deeper permafrost and peatland strata down to several tens of meters depth where SOC is usually not affected by short-term changes. We address key factors (permafrost, vegetation, hydrology, paleoenvironmental history) …

Adaptive Management Of Bull Trout Populations In The Lemhi Basin, Andrew J. Tyre, James T. Peterson, Sarah J. Converse, Tiffany Bogich, Damien Miller, Max Post Van Der Burg, Carmen Thomas, Ralph Thompson, Jeri Wood, Donna C. Brewer, Michael C. Runge

School of Natural Resources: Faculty Publications

The bull trout Salvelinus confluentus, a stream-living salmonid distributed in drainages of the northwestern United States, is listed as threatened under the Endangered Species Act because of rangewide declines. One proposed recovery action is the reconnection of tributaries in the Lemhi Basin. Past water use policies in this core area disconnected headwater spawning sites from downstream habitat and have led to the loss of migratory life history forms. We developed an adaptive management framework to analyze which types of streams should be prioritized for reconnection under a proposed Habitat Conservation Plan. We developed a Stochastic Dynamic Program that identified optimal …

Characterizing The Performance Of Ecosystem Models Across Time Scales: A Spectral Analysis Of The North American Carbon Program Site-Level Synthesis, Michael C. Dietze, Rodrigo Vargas, Andrew D. Richardson, Paul C. Stoy, Alan G. Barr, Ryan S. Anderson, M. Altaf Arain, Ian T. Baker, T. Andrew Black, Jing M. Chen, Philippe Ciais, Lawrence B. Flanagan, Christopher M. Gough, Robert F. Grant, David Hollinger, R. Cesar Izaurralde, Christopher J. Kucharik, Peter Lafleur, Shugang Liu, Erandathie Lokupitiya, Yiqi Luo, J. William Munger, Changhui Peng, Benjamin Poulter, David T. Price, Daniel M. Ricciuto, William J. Riley, Alok Kumar Sahoo, Kevin Schaefer, Andrew E. Suyker, Hanqin Tian, Christina Tonitto, Hans Verbeeck, Shashi B. Verma, Weifeng Wang, Ensheng Weng

School of Natural Resources: Faculty Publications

Ecosystem models are important tools for diagnosing the carbon cycle and projecting its behavior across space and time. Despite the fact that ecosystems respond to drivers at multiple time scales, most assessments of model performance do not discriminate different time scales. Spectral methods, such as wavelet analyses, present an alternative approach that enables the identification of the dominant time scales contributing to model performance in the frequency domain. In this study we used wavelet analyses to synthesize the performance of 21 ecosystem models at 9 eddy covariance towers as part of the North American Carbon Program’s site-level intercomparison. This study …

Heritable Choice Of Colony Size In Cliff Swallows: Does Experience Trump Genetics In Older Birds?, Erin A. Roche, Charles R. Brown, Mary Bomberger Brown

School of Natural Resources: Faculty Publications

The variation in breeding colony size seen in populations of most colonial birds may reflect heritable choices made by individuals that are phenotypically specialized for particular social environments. Although a few studies have reported evidence for genetically based choice of group sizes in birds, we know relatively little about the extent to which animals potentially rely on experience versus innate preferences in deciding how many conspecifics to settle with at different times of their lives. We conducted a cross-fostering experiment in 1997–1998 on cliff swallows, Petrochelidon pyrrhonota, in southwestern Nebraska, USA, in which some individuals were reared in colonies …

Surface Water Characteristics Of The Weaber Plain And Lower Keep River Catchments: Data Review And Preliminary Results, D L. Bennett, Richard J. George Dr

Resource management technical reports

In 2008, the Ord Irrigation Expansion Project was approved by the Western Australian Government to develop irrigated agriculture on the Weaber Plain.

An important concern is the effect the Weaber Plain agricultural development may have on the water quality of the downstream Border Creek and Keep River

This report assembles and reviews all available physico-chemical water quality data for the lower Keep River and Border Creek systems and presents data from the initial year of a targeted baseline monitoring program (June 2010 – June 2013).

Distribution Of Trace Elements In Cumberland River Basin Reservoir Sediments, Laura Mahoney Benneyworth

Masters Theses & Specialist Projects

The U.S. Army Corps of Engineers, Nashville District, maintains ten reservoirs in the Cumberland River Basin in Kentucky and Tennessee, and has been monitoring sediment chemistry in the reservoirs since 1994. The purpose of this study is to evaluate the sediment data collected from the reservoirs from 1994 to 2010 to determine if there are any spatial patterns of the trace elements: arsenic, beryllium, cadmium, chromium, copper, lead, mercury, nickel, and zinc. The results indicated that trace element levels were consistent with national baseline concentrations measured by the U.S. Geological Survey. Center Hill reservoir had the greatest number of trace …

Perception Of Aquifer Depletion And The Effects Of Land Use Change Across The Madaba Plain, Jordan, Mohammad Salem

Graduate Theses and Dissertations

In Jordan, demand for water for agricultural purposes has put a high strain on aquifer resources. Water mining, erosion, and desertification have all increased as global temperatures rise. This along with fragmentation of the landscape have altered the environment in a profound way. The Madaba Plain was chosen for this study due to the agricultural activities that take place there, as well as the proximity to a number of population centers. The purpose of the study is to examine how fragmentation of irrigated landscape has affected the aquifers underneath, while taking into account perceptions of risk of the local population. …

Removal Of Disinfection By-Product Precursors Using Magnetic Ion Exchange (Miex(R)): The Effects Of Ph And Source Water Variability, Sarah Cousins

Graduate Theses and Dissertations

Disinfection by-products (DBPs) form as an unintended result of drinking water disinfection, from chemical reactions between disinfectants (e.g., free chlorine) and naturally occurring dissolved organic matter (DOM). At present, 11 DBPs are regulated in treated drinking waters due to potential adverse health effects, including four trihalomethanes (THMs). Despite nearly 40 years of DBP research, compliance with DBP regulations remains a challenge for many drinking water treatment plants (DWTPs), including the four DWTPs located on the Beaver Lake Reservoir in Northwest Arkansas. Due to the high net negative surface charge on DOM, anion exchange is one potentially viable method for removing …

Genetic Structure Of Grass Carp Populations In The Missouri And Mississippi River Basins, Usa, Bobbi M. Adams, Katie N. Bertrand, Michael L. Brown, Donald Auger

The Prairie Naturalist

We provided an early characterization of the genetic structure of the grass carp (Ctenopharyngodon idella) population as it expands its distribution in both the Missouri and Mississippi River basins. Further, we provided initial comparisons of allelic richness at 17 polymorphic microsatellite markers between 56 grass carp from the USA, and six from the Yangtze River in China. The number of alleles per locus ranged from two to eight and size ranges of alleles for fish collected from the invaded and native ranges were similar (P ≤ 0.001; 107–226 bp) to those previously reported in the literature. Distance-based clustering …

Notes On The Distribution Of Eastern Woodrats And Hispid Cotton Rats In South-Central Nebraska, Heather D. Wills, Keith Geluso, Eric J. Smits, Joseph T. Springer, Wesley E. Newton

The Prairie Naturalist

The eastern woodrat (Neotoma floridana) and hispid cotton rat (Sigmodon hispidus) reach distributional limits in southern Nebraska (Jones 1964, Farney 1975). In the last half-century, both species have expanded their distributional ranges in the region (Kugler and Geluso 2009, Wright et al. 2010). Herein, we report new localities of occurrence for both species that extend known distributional boundaries in south-central Nebraska beyond those reported by Kugler and Geluso (2009) and Wright et al. (2010).

Associated with other studies, we captured small mammals in Sherman live-traps in south-central Nebraska. Voucher specimens were deposited in collections at the …

Comparison Of Fish Communities In Recently Constructed Side-Channel Chutes With The Main Stem Missouri River, Kasey Whiteman, Vincent H. Travnichek, Darrick L. Garner, Brandon Eder, Kirk Steffensen

The Prairie Naturalist

Two United States Army Corp of Engineers- (USACE) funded projects were conducted from 2006 to 2008 along the Missouri River to monitor fish communities in recently constructed side-channel chutes and to monitor pallid sturgeon (Scaphirhynchus albus) and the associated fish assemblage in the main stem Missouri River. Data from both monitoring projects were compared to evaluate fish assemblages among four mitigated habitats (e.g., constructed side-channel chutes) and the main-stem Missouri River. Chutes had a greater overall number of species (n = 59) and higher species richness (Margalef’s index = 5.81), but richness was not different (F1, 4 = …

Patterns Of Age-0 Gizzard Shad Abundance And Food Habits In A Nebraska Irrigation Reservoir, Christopher L. Sullivan, Casey W. Schoenebeck, Keith D. Koupal, W. Wyatt Hoback, Brian C. Peterson

The Prairie Naturalist

Gizzard shad (Dorosoma cepedianum) are prolific spawners that can influence reservoir communities. Larval gizzard shad may compete with larval recreational fish for zooplankton resources. Therefore, it is necessary to determine larval gizzard shad dynamics and food habits to better understand their potential for competition with larval recreational fish. Our study examined age-0 gizzard shad abundance in Harlan County Reservoir during late spring/summer from 2002–2010 and food habits and prey electivity of age-0 gizzard shad during late spring/summer 2008 and 2009. The annual peak age-0 gizzard shad density 3 from 2002–2010 ranged from 50 to 380/100 m , which …

Northern Harrier Hatches Mallard Nest, Jeffery W. Stackhouse, Benjamin A. Geaumont

The Prairie Naturalist

The northern harrier (Circus cyaneus) is a widespread raptor commonly found nesting throughout the Northern Great Plains. Northern harriers forage primarily on small mammals and passerines with the males providing the majority of prey to nestlings until 14–28 days of age (Redpath et al. 2006, Vukovich and Ritchison 2006). Although the genus Circus is known to predate eggs from nest of many nesting birds (Hiraldo et al. 1975, Donaszar et al. 1996, Opermanis et al. 2000), few have been recorded commandeering nests of different species (Laine 1928, Fleskes 1992). In June 2010, we observed a northern harrier that …

Late Seasonal Captures Of The Plains Pocket Mouse (Perognathus Flavescens) In Iowa, Hans W. Otto, Jeremy A. White

The Prairie Naturalist

The plains pocket mouse, Perognathus flavescens, is a nocturnal granivore that inhabits friable soils in sparsely vegetated areas (Monk and Jones 1996). In the United States, the distribution of the plains pocket mouse extends from Arizona, New Mexico, and Texas through the Great Plains to North Dakota and Minnesota (Hall 1981). This species reaches its easternmost limits in Iowa, where it has been documented from a limited number of grassland sites in eastern, central, and western parts of the state (Bowles 1975, Wilson et al. 1996). Due to loss of grassland habitat, the plains pocket mouse is currently listed …

Missouri National Recreational River, Natural Resource Condition Assessment, Kevin J. Stark, Lucas J. Danzinger, Michael R. Komp, Andy J. Nadeau, Shannon Amberg, Eric J. Iverson, David Kadlec, Barry Drazkowski

United States National Park Service: Publications

Executive Summary

As a unit in the National Park Service (NPS), Missouri National Recreational River (MNRR) is responsible for the management and conservation of natural resources within its boundaries. This mandate is supported by the National Park Service Organic Act of 1916, which directs the NPS to:

conserve the scenery and natural and historic objects and the wildlife therein and to provide for the enjoyment of the same in such a manner and by such means as will leave them unimpaired for the enjoyment of future generations.

In 2003, NPS Water Resources Division received funding through the Natural Resource Challenge …

Feasibility Study And Best Practices For A Campus Community Garden On The University Of Arkansas Campus, Samantha Jones

Crop, Soil and Environmental Sciences Undergraduate Honors Theses

Although community gardening on college campuses is not a new concept, campus community gardens have recently grown in popularity. Campus community gardens, however, have not been extensively researched. In order to better understand campus community gardens and to determine the feasibility of a campus community garden at the University of Arkansas in Fayetteville (UAF), this study was conducted in three components. An online survey of 88 campus community gardens in the United States and Canada served as the first national survey of universities and colleges with campus community gardens. The survey included demographic information, management, funding, liabilities, risks, obstacles and …

Scotts Bluff National Monument Plant Community Composition And Structure Monitoring, 2011 Annual Report, Isabel W. Ashton, Michael Prowatzke, Michael R. Bynum, Tim Shepherd, Stephen K. Wilson, Kara Paintner-Green

United States National Park Service: Publications

Executive Summary

The Northern Great Plains Inventory & Monitoring Network (NGPN) was established to develop and provide scientifically credible information on the current status and long-term trends of the composition, structure, and function of ecosystems in thirteen parks located in five northern Great Plains states. NGPN identified upland plant communities, exotic plant early detection, and riparian lowland communities as vital signs that can be used to better understand the condition of terrestrial park ecosystems (Gitzen et al. 2010). Upland and riparian ecosystems are important targets for vegetation monitoring because the status and trends in plant communities provide critical insights into …

Agate Fossil Beds National Monument Plant Community Composition And Structure Monitoring, 2011 Annual Report, Isabel W. Ashton, Michael Prowatzke, Michael R. Bynum, Tim Shepherd, Stephen K. Wilson, Kara Paintner-Green

United States National Park Service: Publications

Executive Summary

The Northern Great Plains Inventory & Monitoring Network (NGPN) was established to develop and provide scientifically credible information on the current status and long-term trends of the composition, structure, and function of ecosystems in thirteen parks located in five northern Great Plains states. NGPN identified upland plant communities, exotic plant early detection, and riparian lowland communities as vital signs that can be used to better understand the condition of terrestrial park ecosystems (Gitzen et al. 2010). Upland and riparian ecosystems are important targets for vegetation monitoring because the status and trends in plant communities provide critical insights into …

A Comparison Of The Effectiveness Of Scent Lures On Attracting Mesopredators, Tom Batter

Department of Environmental Studies: Undergraduate Student Theses

A mesopredator is a medium-sized middle trophic level predator such as a raccoon (Procyon lotor), red fox (Vulpes vulpes), striped skunk (Mephitis mephitis), or coyote (Canis latrans; Crooks and Soule 1999). Mesopredators have long been trapped for recreational, economic, or academic reasons. Throughout human history trapping has been used to capture animals for food and skins, as well as to prevent personal harm and property damage from predators. In order to increase the probability of success, scent lures are often used as an attractant (Geary 1984, Mills et al. 2010, Schlexer 2008).

Herpetofaunal Diversity At Yankee Hill State Lake And Wildlife Management Area, Lancaster County, Nebraska, Shelby Klima

Department of Environmental Studies: Undergraduate Student Theses

A survey for amphibians and reptiles was conducted in March through October 2011 at Yankee Hill Wildlife Management Area in Lancaster County, Nebraska. The survey was conducted using several different techniques including: visual and auditory encounters, artificial and natural cover objects, aquatic trappings and road surveys. A total of 145 individuals representing 12 species were identified including seven reptiles and five amphibians. A total of 48% of the species that may potentially occur on the site were encountered, all of which are common, widely distributed generalist species. Neither Graham’s Crayfish Snake nor the Massasauga, both target species for this survey, …

Avian Species Abundance In Response To Recreational Trail Use, Carrie A. Wencel

Department of Environmental Studies: Undergraduate Student Theses

Studies have indicated that non-consumptive outdoor recreation may affect wildlife. Thus, as the nation increases interest in outdoor recreation, data suggests the effect on wildlife will also increase. Previous studies indicate that as disturbance to wildlife increases, both avian species richness will decrease. Knowing how to anticipate effects on native species when planning and managing recreational areas is important in order to both provide for human desires and ensure the least impact to local species diversity.

The goal of this project was to observe and compare avian species richness and diversity between selected trail sites within Shevlin Park, Bend, Oregon …

Prey Selection By The Northern Watersnake, Nerodia Sipedon, Kyle O' Connell

Department of Environmental Studies: Undergraduate Student Theses

Prey selection and composition of the northern waternake, Nerodia sipedon was investigated between 8/2010 and 3/2011 by palpation of stomach contents in the field and conducting laboratory trials. 41 snakes were captured, five yielded prey contents. Fish parts, freshwater mussels, and an insect exoskeleton were found. No amphibians were found despite availability at study sites. Snakes in the laboratory underwent 22 trials, feeding on 11 occasions. Snakes fed on an equal number of both fish species, revealing no selection. Further research is needed to determine the rate of digestion of N. sipedon.