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Full-Text Articles in Environmental Indicators and Impact Assessment

The Effect Of Diet On The Bovine Rumen Microbial Community Structure And Composition And Its Effects On Methane Production In Growing And Finishing Cattle, Allison L. Knoell Apr 2016

The Effect Of Diet On The Bovine Rumen Microbial Community Structure And Composition And Its Effects On Methane Production In Growing And Finishing Cattle, Allison L. Knoell

Department of Animal Science: Dissertations, Theses, and Student Research

Methane is a potent greenhouse gas (GHG) that contributes to global warming. A natural by-product of ruminant fermentation is the production and eructation of methane. Methane is produced by a small unique group of microorganism’s called methanogens that belong to the domain Archaea. Enteric methane represents 2-12% energy loss in ruminants. It is well established that diet affects the microbial community structure and composition. Fermentative products of the mixed microbial population (bacteria, fungi, and protozoa) become the substrates for methanogens. These substrates influence which microorganisms will thrive. However, the effect of diet on the microbial community while simultaneously calculating …


Behavioral Responses And Policy Evaluation: Revisiting Water And Fuel Policies, Shanxia Sun Apr 2016

Behavioral Responses And Policy Evaluation: Revisiting Water And Fuel Policies, Shanxia Sun

Open Access Dissertations

In my dissertation, I examine how policies regulating agricultural production and clean technology impact the environment. I focus on policies affecting water depletion, water pollution, and fuel consumption. I assess their cost-effectiveness by modeling and quantifying the behavioral responses of farmers and households.

My first essay focuses on decreasing groundwater depletion through increasing irrigation efficiency in Mexico. I quantify the impacts of different sources of inefficiency on groundwater extraction, and I evaluate the effectiveness of alternative policies that aim to reduce the over-extraction of groundwater. I find that mechanisms of electricity cost-sharing implemented in many wells have a sizable impact …


Wildlife Underpasses: Frequency Of Use By Neotropic Mammals In Parque Natural Metropolitano, Panamá City, Panamá, Kelly Russo Apr 2016

Wildlife Underpasses: Frequency Of Use By Neotropic Mammals In Parque Natural Metropolitano, Panamá City, Panamá, Kelly Russo

Independent Study Project (ISP) Collection

In a world of ever increasing globalization and urbanization, roads present wildlife with a number of challenges. They fragment habitats, disrupt animal movements, impact reproductive success and the fitness of individuals and populations, alter population dynamics, and cause unnatural levels of mortality. Fortunately, the numerous detrimental effects of roads can be alleviated by the proper implementation of mitigation structures, such as underpasses, sky bridges and vegetated overpasses. These mitigation structures are an important source of genetic connectivity, especially in a peri-urban reserve setting. This study seeks to understand what species of mammal utilize the wildlife underpasses below Via La Amistad, …


L’Insecte Sage In The Age Of Global Climate Crisis: A Biocultural And Ontological Study Of Vulnerability And Resilience In The Manakara Beekeeping Network, Tamar Law Apr 2016

L’Insecte Sage In The Age Of Global Climate Crisis: A Biocultural And Ontological Study Of Vulnerability And Resilience In The Manakara Beekeeping Network, Tamar Law

Independent Study Project (ISP) Collection

The effects of climate change are felt unevenly throughout the globe. Impoverished populations with high levels of subsistence agriculture are particularly vulnerable due to their direct dependence on the land. However, these populations are also the possible agents of change and solutions, as their traditional ecological knowledge has evolved in relation to their context. The honeybee is directly implicated in climate change vulnerability due to its role in pollination services, by ensuring food security. In the past decade, honeybees have risen to international fame and scrutiny due to a global vanishing of bees, attributed in part to climate change and …


U.S. Drought Monitor, March 29, 2016, Brad Rippey Mar 2016

U.S. Drought Monitor, March 29, 2016, Brad Rippey

United States Agricultural Commodities in Drought Archive

Drought map of U.S. for March 29, 2016 (3/29/16) plus: U.S. crop areas experiencing drought (map), Approximate percentage of crop located in drought, by state (bar graph), Percent of crop area located in drought, past 52 weeks (line graph) for: Corn, Soybeans, Hay, Cattle, Winter wheat.


U.S. Drought Monitor, March 22, 2016, Brad Rippey Mar 2016

U.S. Drought Monitor, March 22, 2016, Brad Rippey

United States Agricultural Commodities in Drought Archive

Drought map of U.S. for March 22, 2016 (3/22/16) plus: U.S. crop areas experiencing drought (map), Approximate percentage of crop located in drought, by state (bar graph), Percent of crop area located in drought, past 52 weeks (line graph) for: Corn, Soybeans, Hay, Cattle, Winter wheat.


U.S. Drought Monitor, March 15, 2016, Richard R. Heim Jr. Mar 2016

U.S. Drought Monitor, March 15, 2016, Richard R. Heim Jr.

United States Agricultural Commodities in Drought Archive

Drought map of the United States for March 15, 2016 (3/15/16) plus: United States crop areas experiencing drought (map), the approximate percentage of crop located in drought by state (bar graph), and the percentage of crop area located in drought during past 52 weeks (line graph) for corn, soybeans, hay, cattle, and winter wheat.


Developing Probability Maps For Locating And Scouting Unprotected Areas Of Gravel Hill Prairies On Rodman Soils Along The Wabash River Valley Near Lafayette, Indiana, Ryan W.R. Schroeder Mar 2016

Developing Probability Maps For Locating And Scouting Unprotected Areas Of Gravel Hill Prairies On Rodman Soils Along The Wabash River Valley Near Lafayette, Indiana, Ryan W.R. Schroeder

Engagement & Service-Learning Summit

No abstract provided.


U.S. Drought Monitor, March 8, 2016, David Miskus Mar 2016

U.S. Drought Monitor, March 8, 2016, David Miskus

United States Agricultural Commodities in Drought Archive

Drought map of U.S. for March 8, 2016 (3/8/16) plus: U.S. crop areas experiencing drought (map), Approximate percentage of crop located in drought, by state (bar graph), Percent of crop area located in drought, past 52 weeks (line graph) for: Corn, Soybeans, Hay, Cattle, Winter wheat.


U.S. Drought Monitor, March 1, 2016, David Miskus Mar 2016

U.S. Drought Monitor, March 1, 2016, David Miskus

United States Agricultural Commodities in Drought Archive

Drought map of U.S. for March 1, 2016 (3/1/16) plus: U.S. crop areas experiencing drought (map), Approximate percentage of crop located in drought, by state (bar graph), Percent of crop area located in drought, past 52 weeks (line graph) for: Corn, Soybeans, Hay, Cattle, Winter wheat.


U.S. Drought Monitor, February 23, 2016, Eric Luebehusen Feb 2016

U.S. Drought Monitor, February 23, 2016, Eric Luebehusen

United States Agricultural Commodities in Drought Archive

Drought map of U.S. for February 23, 2016 (2/23/16) plus: U.S. crop areas experiencing drought (map), Approximate percentage of crop located in drought, by state (bar graph), Percent of crop area located in drought, past 52 weeks (line graph) for: Corn, Soybeans, Hay, Cattle, Winter wheat.


U.S. Drought Monitor, February 16, 2016, Eric Luebehusen Feb 2016

U.S. Drought Monitor, February 16, 2016, Eric Luebehusen

United States Agricultural Commodities in Drought Archive

Drought map of U.S. for February 16, 2016 (2/16/16) plus: U.S. crop areas experiencing drought (map), Approximate percentage of crop located in drought, by state (bar graph), Percent of crop area located in drought, past 52 weeks (line graph) for: Corn, Soybeans, Hay, Cattle, Winter wheat.


U.S. Drought Monitor, February 9, 2016, Anthony Artusa Feb 2016

U.S. Drought Monitor, February 9, 2016, Anthony Artusa

United States Agricultural Commodities in Drought Archive

Drought map of U.S. for February 9, 2016 (2/9/16) plus: U.S. crop areas experiencing drought (map), Approximate percentage of crop located in drought, by state (bar graph), Percent of crop area located in drought, past 52 weeks (line graph) for: Corn, Soybeans, Hay, Cattle, Winter wheat.


Bats Serves As Nebraska's Natural Pest Control Agents, Michael Whitby, Craig R. Allen Feb 2016

Bats Serves As Nebraska's Natural Pest Control Agents, Michael Whitby, Craig R. Allen

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

You don't notice them flying in the night sky as you drive home, or in the trees above you as you walk your dog or under the bark of the dead tree at your fishing hole, but bats are everywhere in Nebraska. In fact, there are 13 species of bats inhabiting our state. They exhibit a wide variety of shapes, sizes and colors. Some migrate to unknown locations each winter. others stay in Nebraska and hibernate in caves, mines and occasionally homes. You probably won't notice them unless you happen to catch a glimpse of one eating insects under a …


U.S. Drought Monitor, February 2, 2016, Anthony Artusa Feb 2016

U.S. Drought Monitor, February 2, 2016, Anthony Artusa

United States Agricultural Commodities in Drought Archive

Drought map of U.S. for February 2, 2016 (2/2/16) plus: U.S. crop areas experiencing drought (map), Approximate percentage of crop located in drought, by state (bar graph), Percent of crop area located in drought, past 52 weeks (line graph) for: Corn, Soybeans, Hay, Cattle, Winter wheat.


U.S. Drought Monitor, January 26, 2016, Mark D. Svoboda Jan 2016

U.S. Drought Monitor, January 26, 2016, Mark D. Svoboda

United States Agricultural Commodities in Drought Archive

Drought map of U.S. for January 26, 2016 (1/26/16) plus: U.S. crop areas experiencing drought (map), Approximate percentage of crop located in drought, by state (bar graph), Percent of crop area located in drought, past 52 weeks (line graph) for: Corn, Soybeans, Hay, Cattle, Winter wheat.


U.S. Drought Monitor, January 19, 2016, Mark D. Svoboda Jan 2016

U.S. Drought Monitor, January 19, 2016, Mark D. Svoboda

United States Agricultural Commodities in Drought Archive

Drought map of U.S. for January 19, 2016 (1/19/16) plus: U.S. crop areas experiencing drought (map), Approximate percentage of crop located in drought, by state (bar graph), Percent of crop area located in drought, past 52 weeks (line graph) for: Corn, Soybeans, Hay, Cattle, Winter wheat.


Spatial Analysis Of Forest Crimes In Mark Twain National Forest, Missouri, Karun Pandit, Eddie Bevilacqua, Giorgos Mountrakis, Robert W. Malmsheimer Jan 2016

Spatial Analysis Of Forest Crimes In Mark Twain National Forest, Missouri, Karun Pandit, Eddie Bevilacqua, Giorgos Mountrakis, Robert W. Malmsheimer

Journal of Geospatial Applications in Natural Resources

Forest crime mitigation has been identified as a challenging issue in forest management in the United States. Knowledge of the spatial pattern of forest crimes would help in wisely allocating limited enforcement resources to curb forest crimes. This study explores the spatial pattern of three different types of forest crimes: fire crime, illegal timber logging crime, and occupancy use crime in the Salem-Patosi Ranger District of Mark Twain National Forest. Univariate and bivariate Ripley’s K-functions were applied to explore the spatial patterns in crime events, like clustering and attraction among forest crime types. Results reveal significant clustering for each forest …


Comparison Of Terrain Indices And Landform Classification Procedures In Low-Relief Agricultural Fields, Derek A. Evans, Karl W. J. Williard, Jon E. Schoonover Jan 2016

Comparison Of Terrain Indices And Landform Classification Procedures In Low-Relief Agricultural Fields, Derek A. Evans, Karl W. J. Williard, Jon E. Schoonover

Journal of Geospatial Applications in Natural Resources

Landforms control the spatial distribution of numerous factors associated with agronomy and water quality. Although curvature and slope are the fundamental surface derivatives used in landform classification procedures, methodologies for landform classifications have been performed with other terrain indices including the topographic position index (TPI) and the convergence index (CI). The objectives of this study are to compare plan curvature, the convergence index, profile curvature, and the topographic position index at various scales to determine which better identifies the spatial variability of soil phosphorus (P) within three low relief agricultural fields in central Illinois and to compare how two methods …


Discordant Data And Interpretation Of Results From Wildlife Habitat Models, Anita T. Morzillo, Michael G. Wing, Justin Long Jan 2016

Discordant Data And Interpretation Of Results From Wildlife Habitat Models, Anita T. Morzillo, Michael G. Wing, Justin Long

Journal of Geospatial Applications in Natural Resources

Wildlife habitat management is an important part of natural resource management. As a result, there are a large number of models and tools for wildlife habitat assessment. A consequence of the many assessment tools is inconsistency when comparing results between tools, which may lead to potential confusion management decisions. Our objective was to compare results from two wildlife habitat models – one being relatively coarse (HUC5) scale and not spatially dynamic and the other being finer scale spatial data based on a 30 m spatial resolution –for habitat assessment of three species across the West Cascades of Oregon: Northern spotted …


U.S. Drought Monitor, January 12, 2016, Brian Fuchs Jan 2016

U.S. Drought Monitor, January 12, 2016, Brian Fuchs

United States Agricultural Commodities in Drought Archive

Drought map of U.S. for January 12, 2016 (1/12/16) plus: U.S. crop areas experiencing drought (map), Approximate percentage of crop located in drought, by state (bar graph), Percent of crop area located in drought, past 52 weeks (line graph) for: Corn, Soybeans, Hay, Cattle, Winter wheat.


U.S. Drought Monitor, January 5, 2016, Brian Fuchs Jan 2016

U.S. Drought Monitor, January 5, 2016, Brian Fuchs

United States Agricultural Commodities in Drought Archive

Drought map of U.S. for January 5, 2016 (1/5/16) plus: U.S. crop areas experiencing drought (map), Approximate percentage of crop located in drought, by state (bar graph), Percent of crop area located in drought, past 52 weeks (line graph) for: Corn, Soybeans, Hay, Cattle, Winter wheat.


Ex-Situ Conservation Programs: Worthwhile?, Nicolette Sliwa, Aaron Sieve Jan 2016

Ex-Situ Conservation Programs: Worthwhile?, Nicolette Sliwa, Aaron Sieve

Biology: Student Scholarship & Creative Works

The effectiveness of conservation programs was researched, specifically within zoos, and their attempts to repopulate areas with captive-born individuals of endangered species. There are major biological and economic concerns with these programs focused on, including potential genetic adaptation to captivity, effects of inbreeding, and if this is a truly worthwhile use of funds to restore a species. Looking at the black-footed ferret, the whooping crane, and other supposed successful captive-breeding programs, it is explored whether reintroduced individuals thrive in their new habitats sufficiently enough to contribute to the restoration of the species, and more broadly, their ecosystems.


Marine Ecoregion And Deepwater Horizon Oil Spill Affect Recruitment And Population Structure Of A Salt Marsh Snail, Steven C. Pennings, Scott Zengel, Jacob Oehrig, Merryl Alber, T. Dale Bishop, Donald R. Deis, Donna Devlin, A. Randall Hughes, John J. Hutchens, Jr., Whitney M. Kiehn, Caroline R. Mcfarlin, Clay L. Montague, Sean P. Powers, C. Edward Proffitt, Nicholle Rutherford, Camille L. Stagg, Keith Walters Jan 2016

Marine Ecoregion And Deepwater Horizon Oil Spill Affect Recruitment And Population Structure Of A Salt Marsh Snail, Steven C. Pennings, Scott Zengel, Jacob Oehrig, Merryl Alber, T. Dale Bishop, Donald R. Deis, Donna Devlin, A. Randall Hughes, John J. Hutchens, Jr., Whitney M. Kiehn, Caroline R. Mcfarlin, Clay L. Montague, Sean P. Powers, C. Edward Proffitt, Nicholle Rutherford, Camille L. Stagg, Keith Walters

University Faculty and Staff Publications

Marine species with planktonic larvae often have high spatial and temporal variation in recruitment that leads to subsequent variation in the ecology of benthic adults. Using a combination of published and unpublished data, we compared the population structure of the salt marsh snail, Littoraria irrorata, between the South Atlantic Bight and the Gulf Coast of the United States to infer geographic differences in recruitment and to test the hypothesis that the Deepwater Horizon oil spill led to widespread recruitment failure of L. irrorata in Louisiana in 2010. Size-frequency distributions in both ecoregions were bimodal, with troughs in the distributions consistent …


Impacts Of Man-Made Structures On Avian Community Metrics In 4 State Parks In Northwestern Arkansas, R. D. Keith, B. Grooms, R. E. Urbanek Jan 2016

Impacts Of Man-Made Structures On Avian Community Metrics In 4 State Parks In Northwestern Arkansas, R. D. Keith, B. Grooms, R. E. Urbanek

Journal of the Arkansas Academy of Science

Avian community metrics often differ between areas with no human disturbance and areas with high levels of human disturbance. However, the relationships between avian community metrics and smaller-scale disturbances are not as clear. Our goal was to investigate if avian abundance, richness, evenness, and diversity differed in areas with and without small-scale human developments. We used fixed-radius 50-m avian point counts to compare points which contained a man-made structure (n = 47), such as a picnic area, road, or campsite to those that did not contain a man-made structure (n = 181) at 4 state parks in Arkansas during 18 …


The Influence Of A Severe Reservoir Drawdown On Springtime Zooplankton And Larval Fish Assemblages In Red Willow Reservoir, Nebraska, Jason A. Deboer, Christa M. Webber, Taylor A. Dixon, Kevin L. Pope Jan 2016

The Influence Of A Severe Reservoir Drawdown On Springtime Zooplankton And Larval Fish Assemblages In Red Willow Reservoir, Nebraska, Jason A. Deboer, Christa M. Webber, Taylor A. Dixon, Kevin L. Pope

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Reservoirs can be dynamic systems, often prone to unpredictable and extreme waterlevel fluctuations, and can be environments where survival is difficult for zooplankton and larval fish. Although numerous studies have examined the effects of extreme reservoir drawdown on water quality, few have examined extreme drawdown on both abiotic and biotic characteristics. A fissure in the dam at Red Willow Reservoir in southwest Nebraska necessitated an extreme drawdown; the water level was lowered more than 6 m during a two-month period, reducing reservoir volume by 76%. During the subsequent low-water period (i.e., post-drawdown), spring sampling (April-June) showed dissolved oxygen concentration was …


Potential Population And Assemblage Influences Of Non-Native Trout On Native Nongame Fish In Nebraska Headwater Streams, Kelly C. Turek, Mark A. Pegg, Kevin L. Pope, Steve Schainost Jan 2016

Potential Population And Assemblage Influences Of Non-Native Trout On Native Nongame Fish In Nebraska Headwater Streams, Kelly C. Turek, Mark A. Pegg, Kevin L. Pope, Steve Schainost

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Non-native trout are currently stocked to support recreational fisheries in headwater streams throughout Nebraska. The influence of non-native trout introductions on native fish populations and their role in structuring fish assemblages in these systems is unknown. The objectives of this study were to determine (i) if the size structure or relative abundance of native fish differs in the presence and absence of non-native trout, (ii) if native fish-assemblage structure differs in the presence and absence of non-native trout and (iii) if native fish-assemblage structure differs across a gradient in abundances of non-native trout. Longnose dace Rhinichthys cataractae were larger in …


Letter Resisting Resilience Theory: Aresponse To Connelland Ghedini, Shana M. Sundstrom, Craig R. Allen, Lance H. Gunderson Jan 2016

Letter Resisting Resilience Theory: Aresponse To Connelland Ghedini, Shana M. Sundstrom, Craig R. Allen, Lance H. Gunderson

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

ConnellandGhedini [1] arguethatecolo- gistsareprimarily [1TD$DIF]concernedwithcommu- nitychangeandtendtoignoreprocesses liketrophiccompensationthatcontribute to communityorsystem-levelstability. Resilience,theyclaim,isthestudyof change,andresearchersshouldspend moretimestudyingstabilizingprocesses to betterpredictthetypesofchanges documentedbyecologistswhostudyresil- ience [2,3]. Thebulkoftheirpaper addressesresilienceandrelatedconcepts to contextualizeresistancetochange,but theirargumentsarediminishedbecause theauthorsfailtoexplicitlyplacetheirwork withintherangeofresilienceconceptsthat haveproliferatedacrossacademicdisci- plines.Moreimportantly,thepaperfurthers confusionregardingcoreecologicalresil- ienceconcepts.Withinthedisciplineof ecology,resilienceconceptshavebeen developedinafundamentallycohesive way [4]. Understandingtheresilienceof complexsystemsofhumansandnature duringthistimeofrapidglobalchangeis importantandthemisuseorcasualuseof conceptswithspecific meaningismore thansimplyatrivialpointofcontention;it potentiallyobscuresprocessesandprop- ertiesthathavedirectrelevancetohuman- ity'sinteractionwiththeenvironment.


Influence Of Anglers’ Specializations On Catch, Harvest, And Bycatch Of Targeted Taxa, Kevin L. Pope, Christopher J. Chizinski, Christopher L. Wiley, Dustin R. Martin Jan 2016

Influence Of Anglers’ Specializations On Catch, Harvest, And Bycatch Of Targeted Taxa, Kevin L. Pope, Christopher J. Chizinski, Christopher L. Wiley, Dustin R. Martin

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Fishery managers often use catch per unit effort (CPUE) of a given taxon derived from a group of anglers,those that sought said taxon, to evaluate fishery objectives because managers assume CPUE for this group of anglers is most sensitive to changes in fish taxon density. Further, likelihood of harvest may differ for sought and non-sought taxa if taxon sought is a defining characteristic of anglers’ attitude toward harvest.We predicted that taxon-specific catch across parties and reservoirs would be influenced by targeted taxon after controlling for number of anglers in a party and time spent fishing (combine to quantify fishing effort …


An Ecotoxicological Survey Of Tributaries Of The Selenge River, Mongolia, August 2010, Viktor T. Komov, Ch. Javzan, William G. Brumbaugh Jan 2016

An Ecotoxicological Survey Of Tributaries Of The Selenge River, Mongolia, August 2010, Viktor T. Komov, Ch. Javzan, William G. Brumbaugh

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

The biodiversity of the Selenga river basin and the receiving waters of the lake Baikal, are among the greatest in the world with over 1,700 known endemic species of plants and animals. Mining activities along the Selenga river and its tributaries pose a major threat of chemical contamination, potentially reducing habitat quality and suitability for aquatic species. Moreover, the Selenga river serves as a major water source for the lake Baikal. Little information exists on the chemical contaminant concentrations in the Selenga river basin. Thus, the objectives of our study were to evaluate the concentrations of metals in soil, sediment, …