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Full-Text Articles in Life Sciences

Examples Of Non-Noetherian Domains Inside Power Series Rings, William Heinzer, Christel Rotthaus, Sylvia Wiegand Apr 2014

Examples Of Non-Noetherian Domains Inside Power Series Rings, William Heinzer, Christel Rotthaus, Sylvia Wiegand

Nebraska Cooperative Fish & Wildlife Research Unit -- Staff Publications

Given a power series ring R∗ over a Noetherian integral domain R and an intermediate field L between R and the total quotient ring of R∗, the integral domain A = L ∩ R∗ often (but not always) inherits nice properties from R∗ such as the Noetherian property. For certain fields L it is possible to approximate A using a localization B of a particular nested union of polynomial rings over R associated to A; if B is Noetherian, then B = A. If B is not Noetherian, we can sometimes identify the prime ideals of B that are not finitely generated. We ...


Status Of Native Stream Fishes Within Selected Protected Areas Of The Niobrara River In Western Nebraska, Jonathan J. Spurgeon, Richard H. Stasiak, George R. Cunningham, Kevin L. Pope, Mark A. Pegg Jan 2014

Status Of Native Stream Fishes Within Selected Protected Areas Of The Niobrara River In Western Nebraska, Jonathan J. Spurgeon, Richard H. Stasiak, George R. Cunningham, Kevin L. Pope, Mark A. Pegg

Nebraska Cooperative Fish & Wildlife Research Unit -- Staff Publications

Lotic systems within the Great Plains are characterized by highly fl uctuating conditions through both space and time. Fishes inhabiting these systems have adopted specifi c life- history strategies to survive in such environments; however, anthropogenic disturbance to prairie streams has resulted in declines and extirpation of many native stream fi shes. Terrestrial protected areas (i.e., parks and reserves) are designated to support native fl ora and fauna and, it is assumed, to provide protection to native fi shes. We assessed the presence and relative abundance of stream fi sh populations within protected areas along the Niobrara River in ...


Self-Confidence Of Anglers In Identification Of Freshwater Sport Fish, Christopher J . Chizinski, D. R. Martin, K. L. Pope Jan 2014

Self-Confidence Of Anglers In Identification Of Freshwater Sport Fish, Christopher J . Chizinski, D. R. Martin, K. L. Pope

Nebraska Cooperative Fish & Wildlife Research Unit -- Staff Publications

Although several studies have focused on how well anglers identify species using replicas and pictures, there has been no study assessing the confidence that can be placed in angler’s ability to identify recreationally important fish. Understanding factors associated with low self-confidence will be useful in tailoring education programmes to improve self-confidence in identifying common species. The purposes of this assessment were to quantify the confidence of recreational anglers to identify 13 commonly encountered warm water fish species and to relate self-confidence to species availability and angler experience. Significant variation was observed in anglers selfconfidence among species and levels of ...


Using Posts To An Online Social Network To Assess Fishing Effort, Dustin R. Martin, Christopher J. Chizinski, Kent M. Eskridge, Kevin L. Pope Jan 2014

Using Posts To An Online Social Network To Assess Fishing Effort, Dustin R. Martin, Christopher J. Chizinski, Kent M. Eskridge, Kevin L. Pope

Nebraska Cooperative Fish & Wildlife Research Unit -- Staff Publications

Fisheries management has evolved from reservoir to watershed management, creating a need to simultaneously gather information within and across interacting reservoirs. However, costs to gather information on the fishing effort on multiple reservoirs using traditional creel methodology are often prohibitive. Angler posts about reservoirs online provide a unique medium to test hypotheses on the distribution of fishing pressure. We show that the activity on an online fishing social network is related to fishing effort and can be used to facilitate management goals. We searched the Nebraska Fish and Game Association Fishing Forum for all references from April 2009 to December ...


Assessing And Managing Freshwater Ecosystems Vulnerable To Environmental Change, David G. Angeler, Craig R. Allen, Hannah E. Birgé, Stina Drakare, Brendan G. Mckie, Richard K. Johnson Jan 2014

Assessing And Managing Freshwater Ecosystems Vulnerable To Environmental Change, David G. Angeler, Craig R. Allen, Hannah E. Birgé, Stina Drakare, Brendan G. Mckie, Richard K. Johnson

Nebraska Cooperative Fish & Wildlife Research Unit -- Staff Publications

Freshwater ecosystems are important for global biodiversity and provide essential ecosystem services. There is consensus in the scientific literature that freshwater ecosystems are vulnerable to the impacts of environmental change, which may trigger irreversible regime shifts upon which biodiversity and ecosystem services may be lost. There are profound uncertainties regarding the management and assessment of the vulnerability of freshwater ecosystems to environmental change. Quantitative approaches are needed to reduce this uncertainty. We describe available statistical and modeling approaches along with case studies that demonstrate how resilience theory can be applied to aid decision-making in natural resources management. We highlight especially ...


Panarchy: Theory And Application, Craig R. Allen, David G. Angeler, Ahjond S. Garmestani, Lance H. Gunderson, C. S. Holling Jan 2014

Panarchy: Theory And Application, Craig R. Allen, David G. Angeler, Ahjond S. Garmestani, Lance H. Gunderson, C. S. Holling

Nebraska Cooperative Fish & Wildlife Research Unit -- Staff Publications

The concept of panarchy provides a framework that characterizes complex systems of people and nature as dynamically organized and structured within and across scales of space and time. It has been more than a decade since the introduction of panarchy. Over this period, its invocation in peer-reviewed literature has been steadily increasing, but its use remains primarily descriptive and abstract. Here, we discuss the use of the concept in the literature to date, highlight where the concept may be useful, and discuss limitations to the broader applicability of panarchy theory for research in the ecological and social sciences. Finally, we ...


Predicted Avian Responses To Bioenergy Development Scenarios In An Intensive Agricultural Landscape, Daniel R. Uden, Craig R. Allen, Rob B. Mitchell, Tim D. Mccoy, Qingfeng Guan Jan 2014

Predicted Avian Responses To Bioenergy Development Scenarios In An Intensive Agricultural Landscape, Daniel R. Uden, Craig R. Allen, Rob B. Mitchell, Tim D. Mccoy, Qingfeng Guan

Nebraska Cooperative Fish & Wildlife Research Unit -- Staff Publications

Conversion of native prairie to agriculture has increased food and bioenergy production but decreased wildlife habitat. However, enrollment of highly erodible cropland in conservation programs has compensated for some grassland loss. In the future, climate change and production of second-generation perennial biofuel crops could further transform agricultural landscapes and increase or decrease grassland area. Switchgrass (Panicum virgatum) is an alternative biofuel feedstock that may be economically and environmentally superior to maize (Zea mays) grain for ethanol production on marginally productive lands. Switchgrass could benefit farmers economically and increase grassland area, but there is uncertainty as to how conversions between rowcrops ...


Toxicity Of Copper Sulfate And Rotenone To Chinese Mystery Snail (Bellamya Chinensis), Danielle M. Haak, Bruce J. Stephen, Robert A. Kill, Nicholas A. Smeenk, Craig R. Allen, Kevin L. Pope Jan 2014

Toxicity Of Copper Sulfate And Rotenone To Chinese Mystery Snail (Bellamya Chinensis), Danielle M. Haak, Bruce J. Stephen, Robert A. Kill, Nicholas A. Smeenk, Craig R. Allen, Kevin L. Pope

Nebraska Cooperative Fish & Wildlife Research Unit -- Staff Publications

The Chinese mystery snail (Bellamya chinensis) is a freshwater snail native to Southeast Asia, Japan, and Russia and is currently classified as an invasive species in at least 27 states in the USA. The species tolerates a wide range of environmental conditions, making management of established populations difficult. We tested the efficacy of two traditional chemical treatments, rotenone and copper sulfate, on the elimination of adult Chinese mystery snails in laboratory experiments. All snails (N=50) survived 72-hour exposure to rotenone-treated lake water, and 96% (N=25) survived 72-hour exposure to pre-determined rotenone concentrations of 0.25, 2.5, and ...


Transdisciplinary Application Of Cross-Scale Resilience, Shana M. Sundstrom, David G. Angeler, Ahjond S. Garmestani, Jorge-H. Garcia, Craig R. Allen Jan 2014

Transdisciplinary Application Of Cross-Scale Resilience, Shana M. Sundstrom, David G. Angeler, Ahjond S. Garmestani, Jorge-H. Garcia, Craig R. Allen

Nebraska Cooperative Fish & Wildlife Research Unit -- Staff Publications

The cross-scale resilience model was developed in ecology to explain the emergence of resilience from the distribution of ecological functions within and across scales, and as a tool to assess resilience. We propose that the model and the underlying discontinuity hypothesis are relevant to other complex adaptive systems, and can be used to identify and track changes in system parameters related to resilience. We explain the theory behind the cross-scale resilience model, review the cases where it has been applied to non-ecological systems, and discuss some examples of social-ecological, archaeological/ anthropological, and economic systems where a cross-scale resilience analysis could ...


Assessing Resilience In Stressed Watersheds, Kristine T. Nemec, Joana Chan, Christina Hoffman, Trisha L. Spanbauer, Joseph A. Hamm, Craig R. Allen, Trevor Hefley, Donald Pan, Prabhakar Shrestha Jan 2014

Assessing Resilience In Stressed Watersheds, Kristine T. Nemec, Joana Chan, Christina Hoffman, Trisha L. Spanbauer, Joseph A. Hamm, Craig R. Allen, Trevor Hefley, Donald Pan, Prabhakar Shrestha

Nebraska Cooperative Fish & Wildlife Research Unit -- Staff Publications

Although several frameworks for assessing the resilience of social-ecological systems (SESs) have been developed, some practitioners may not have sufficient time and information to conduct extensive resilience assessments. We have presented a simplified approach to resilience assessment that reviews the scientific, historical, and social literature to rate the resilience of an SES with respect to nine resilience properties: ecological variability, diversity, modularity, acknowledgement of slow variables, tight feedbacks, social capital, innovation, overlap in governance, and ecosystem services. We evaluated the effects of two large-scale projects, the construction of a major dam and the implementation of an ecosystem recovery program, on ...


Habitat Structure And Body Size Distributions: Cross-Ecosystem Comparison For Taxa With Determinate And Indeterminate Growth, Kirsty L. Nash, Craig R. Allen, Chris Barichievy, Magnus Nyström, Nicholas A.J. Graham Jan 2014

Habitat Structure And Body Size Distributions: Cross-Ecosystem Comparison For Taxa With Determinate And Indeterminate Growth, Kirsty L. Nash, Craig R. Allen, Chris Barichievy, Magnus Nyström, Nicholas A.J. Graham

Nebraska Cooperative Fish & Wildlife Research Unit -- Staff Publications

Habitat structure across multiple spatial and temporal scales has been proposed as a key driver of body size distributions for associated communities. Thus, understanding the relationship between habitat and body size is fundamental to developing predictions regarding the infl uence of habitat change on animal communities. Much of the work assessing the relationship between habitat structure and body size distributions has focused on terrestrial taxa with determinate growth, and has primarily analysed discontinuities (gaps) in the distribution of species mean sizes (species size relationships or SSRs). Th e suitability of this approach for taxa with indeterminate growth has yet to ...


Consuming Fire Ants Reduces Northern Bobwhite Survival And Weight Gain, P. Evans Myers, Craig R. Allen, Hannah E. Birge Jan 2014

Consuming Fire Ants Reduces Northern Bobwhite Survival And Weight Gain, P. Evans Myers, Craig R. Allen, Hannah E. Birge

Nebraska Cooperative Fish & Wildlife Research Unit -- Staff Publications

Northern bobwhite quail, Colinus virginianus (L.) (Galliformes: Odontophoridae), population declines are well documented, but pinpointing the reasons for these decreases has proven elusive. Bobwhite population declines are attributed primarily to loss of habitat and land use changes. This, however, does not entirely explain population declines in areas intensively managed for bobwhites. Although previous research demonstrates the negative impact of red imported fire ant (Solenopsis invicta Buren) (Hymenoptera: Formicidae) on northern bobwhites, the mechanisms underlying this effect are largely unknown. To meet the protein demands of early growth and development, bobwhite chicks predominantly consume small insects, of which ants are a ...


Self-Imposed Length Limits In Recreational Fisheries, Christopher J. Chizinski, Dustin R. Martin, Keith L. Hurley, Kevin L. Pope Jan 2014

Self-Imposed Length Limits In Recreational Fisheries, Christopher J. Chizinski, Dustin R. Martin, Keith L. Hurley, Kevin L. Pope

Nebraska Cooperative Fish & Wildlife Research Unit -- Staff Publications

A primary motivating factor on the decision to harvest a fish among consumptive-orientated anglers is the size of the fish. There is likely a cost-benefit trade-off for harvest of individual fish that is size and species dependent, which should produce a logistic-type response of fish fate (release or harvest)as a function of fish size and species. We define the self-imposed length limit as the length at which a captured fish had a 50% probability of being harvested, which was selected because it marks the length of the fish where the probability of harvest becomes greater than the probability of ...


Discontinuities, Cross-Scale Patterns, And The Organization Of Ecosystems, Kirsty L. Nash, Craig R. Allen, David G. Angeler, Chris Barichievy, Tarsha Eason, Ahjond S. Garmestani, Nicholas A. J. Graham, Dean Granholm, Melinda Knutson, R. John Nelson, Magnus Nyström, Craig A. Stow, Shana M. Sundstrom Jan 2014

Discontinuities, Cross-Scale Patterns, And The Organization Of Ecosystems, Kirsty L. Nash, Craig R. Allen, David G. Angeler, Chris Barichievy, Tarsha Eason, Ahjond S. Garmestani, Nicholas A. J. Graham, Dean Granholm, Melinda Knutson, R. John Nelson, Magnus Nyström, Craig A. Stow, Shana M. Sundstrom

Nebraska Cooperative Fish & Wildlife Research Unit -- Staff Publications

Ecological structures and processes occur at specific spatiotemporal scales, and interactions that occur across multiple scales mediate scale-specific (e.g., individual, community, local, or regional) responses to disturbance. Despite the importance of scale, explicitly incorporating a multi-scale perspective into research and management actions remains a challenge. The discontinuity hypothesis provides a fertile avenue for addressing this problem by linking measureable proxies to inherent scales of structure within ecosystems. Here we outline the conceptual framework underlying discontinuities and review the evidence supporting the discontinuity hypothesis in ecological systems. Next we explore the utility of this approach for understanding cross-scale patterns and ...


Introduction: Social-Ecological Resilience And Law, Ahjond S. Garmestani, Craig R. Allen, Craig Anthony Arnold, Lance H. Gunderson Jan 2014

Introduction: Social-Ecological Resilience And Law, Ahjond S. Garmestani, Craig R. Allen, Craig Anthony Arnold, Lance H. Gunderson

Nebraska Cooperative Fish & Wildlife Research Unit -- Staff Publications

Environmental law is intimately connected to ecological concepts and understanding. The legal instruments, institutions, and administration of law in the United States are predicated on assumptions that nature is globally stable and that the inherent variability in ecological systems is bounded. This current legal framework is based upon an understanding of ecological systems operating near an equilibrium, or if disturbed, moving back toward an equilibrium. Such assumptions make much current environmental law ill-suited for many pressing environmental issues (Ruhl 1999; Garmestani et al. 2009; Craig 2010; Verchick 2010; Benson and Garmestani 2011). Emerging environmental challenges, such as cross-boundary water governance ...


Quantifying Spatial Scaling Patterns And Their Local And Regional Correlates In Headwater Streams: Implications For Resilience, Emma Göthe, Leonard Sandin, Craig R. Allen, David G. Angeler Jan 2014

Quantifying Spatial Scaling Patterns And Their Local And Regional Correlates In Headwater Streams: Implications For Resilience, Emma Göthe, Leonard Sandin, Craig R. Allen, David G. Angeler

Nebraska Cooperative Fish & Wildlife Research Unit -- Staff Publications

The distribution of functional traits within and across spatiotemporal scales has been used to quantify and infer the relative resilience across ecosystems. We use explicit spatial modeling to evaluate within- and cross-scale redundancy in headwater streams, an ecosystem type with a hierarchical and dendritic network structure. We assessed the cross-scale distribution of functional feeding groups of benthic invertebrates in Swedish headwater streams during two seasons. We evaluated functional metrics, i.e., Shannon diversity, richness, and evenness, and the degree of redundancy within and across modeled spatial scales for individual feeding groups. We also estimated the correlates of environmental versus spatial ...