Digital Commons Network^™

Quantifying The Adaptive Cycle, David G. Angeler, Craig R. Allen, Ahjond S. Garmestani, Lance H. Gunderson, Olle Hjerne, Monika Winder

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

The adaptive cycle was proposed as a conceptual model to portray patterns of change in complex systems. Despite the model having potential for elucidating change across systems, it has been used mainly as a metaphor, describing system dynamics qualitatively. We use a quantitative approach for testing premises (reorganisation, conservatism, adaptation) in the adaptive cycle, using Baltic Sea phytoplankton communities as an example of such complex system dynamics. Phytoplankton organizes in recurring spring and summer blooms, a well-established paradigm in planktology and succession theory, with characteristic temporal trajectories during blooms that may be consistent with adaptive cycle phases. We used long-term …

Utilizing Ecological Connectivity In California Desert Wilderness Preservation, Lauren Kahal

Master's Projects and Capstones

The Wilderness Act of 1964 gave the federal land management agencies—the National Park Service, United States Forest Service, U.S Fish and Wildlife Service, and Bureau of Land Management—the authority to identify, propose, and manage lands as wilderness. Wilderness, once approved by Congress for inclusion in the National Wilderness Preservation System, is offered the highest form of land preservation in the nation. However, the wilderness identification process used by the implementing agencies is based on a half-century old statute with an aging definition of wilderness. While designated wilderness can protect the plant and wildlife communities within its borders from direct anthropogenic …

Effects Of Short-Term Soil Conditioning By Cheatgrass And Western Wheatgrass, James J. O'Connor, Janet S. Prevey

The Prairie Naturalist

The exotic grass Bromus tectorum (cheatgrass) is a ubiquitous invader in the western USA. Cheatgrass is a proficient competitor, frequently displacing native plants, forming monotypic stands and reducing biodiversity in ecosystems it invades. Our experiment tested whether short-term soil modification by cheatgrass and a predominant native grass, Pascopyrum smithii (western wheatgrass), affected subsequent growth of both species. We compared productivity of cheatgrass and western wheatgrass by harvesting aboveground biomass of plants grown in either cheatgrass- or western wheatgrass-conditioned soils over two simulated growing seasons. Results indicated that cheatgrass soils do not inhibit the productivity of the native grass, but do …

Ecosystem Response To Recent Climate Change In Alpine Environments, Patrick Shawn Sawyer

UNLV Theses, Dissertations, Professional Papers, and Capstones

Recent variations in meteorological conditions indicate the earth’s climate is changing in ways that can impact delicate ecological balances in sensitive regions. These impacts threaten the essential services provided by such ecosystems. Determining how climate changes are affecting the biosphere is essential to adapt and mitigate harmful consequences. In order to mitigate the negative effects of climate change and adapt to shifting ecological resource constraints, it is imperative to locate such changes and determine vulnerability of ecological resources to changing environmental conditions.

Identifying climate driven ecological changes faces numerous challenges given the reliance on vegetation indices as the primary measure …

Remembering Paul B. Kannowski, Robert Seabloom

The Prairie Naturalist

I am saddened to report that Dr. Paul Kannowski passed away 3 September 2015, succumbing to cancer. He was 88. A native of Grand Forks, Paul attended the University of North Dakota for his B.S. and M.S. degrees, and the University of Michigan for his Ph.D. He joined the University of North Dakota Biology Department in 1957, retiring in 1990 after 33 years of service

Paul chaired UND’s Biology Department twice, totaling 13 years, considered to be a remarkable achievement by many of us who have been exposed to that task! His leadership was instrumental in the nearly exponential growth …

Modelling Water Uptake Provides A New Perspective On Grass And Tree Coexistence, Michael G. Mazzacavallo, Andrew Kulmatiski

Wildland Resources Faculty Publications

Root biomass distributions have long been used to infer patterns of resource uptake. These patterns are used to understand plant growth, plant coexistence and water budgets. Root biomass, however, may be a poor indicator of resource uptake because large roots typically do not absorb water, fine roots do not absorb water from dry soils and roots of different species can be difficult to differentiate. In a sub-tropical savanna, Kruger Park, South Africa, we used a hydrologic tracer experiment to describe the abundance of active grass and tree roots across the soil profile. We then used this tracer data to parameterize …

Recreation Ecology Of Colorado Fourteeners: An Assessment Of Trail Usage And Impacts, James C. Ewing

Master's Theses

The popularity of climbing Colorado’s 14,000 ft. peaks, or “Fourteeners”, has risen dramatically in recent years, raising important sustainability and management questions. Moreover, groups managing the peaks operate with major capital constraints so their efforts need to be informed, prioritized, and efficient. This paper gauges the dynamics of trail usage, explanatory variables, and recreational impacts across all 58 Fourteeners, and details evaluation adjustments that minimize error and produce results in-step with the resource management framework. Relative to a baseline study completed in 2005, substantial changes occurred in trail usage and impact dynamics. The greatest changes were concentrated on peaks previously …

The Effect Of Disturbance And Freshwater Availability On Lower Florida Keys’ Coastal Forest Dynamics, Danielle E. Ogurcak

FIU Electronic Theses and Dissertations

Coastal forest retreat in the Florida Keys during the 20^th century has been attributed to a combination of sea level rise and hurricane storm surge impacts, but the interactions between these two disturbances leading to forest decline are not well understood. The goal of my research was to assess their effects over a period spanning more than two decades, and to examine the relationships between these press and pulse disturbances and freshwater availability in pine rockland, hardwood hammock, and supratidal scrub communities. Impacts and recovery from two storm surges, Hurricanes Georges (1998) and Wilma (2005), were assessed with satellite-derived …

Increased Taxonomic And Functional Similarity Does Not Increase The Trophic Similarity Of Communities, Thomas K. Pool, Julien Cucherousset, Stéphanie Boulêtreau, Sébastien Villéger, Angela L. Strecker, Gaël Grenouillet

Environmental Science and Management Faculty Publications and Presentations

Aim: Despite a long-standing research interest in the association between the biodiversity (i.e. taxonomic and functional composition) and trophic structure of communities, our understanding of the relationship remains limited. Community assembly theory predicts that niche partitioning will result in communities with a diverse array of functional traits, which in turn may facilitate a correspondingly diverse array of trophic interactions that define the trophic niche of those communities. The aim of our study is to test this prediction.

Methods: We built a database composed of functional traits and stable isotope values (δ¹³C and δ¹⁵N) for …

'At-Risk' Places: Inequaties In The Distribution Of Environmental Stressors And Prescription Rates Of Mental Health Medications In Glasgow, Scotland, Juliana A. Maantay, Andrew Maroko

Publications and Research

Using geospatial analytical methods, this study examines the association between one aspect of the built environment, namely, the concentration of vacant and derelict land (VDL), and the prevalence of mental health disorders (using the proxy variable of mental health medication prescription rates) in Glasgow, Scotland. This study builds on our previous research, which demonstrated the spatial correspondence between the locations of VDL in Glasgow and several physical health outcomes. Numerous studies of other locales have found similar correspondence between different elements of the built environment and various health outcomes. This is the first study of its kind to look at …

Guide To The Dr. Jane Claire Dirks-Edmunds Papers, Linfield College Archives

Linfield Archives Finding Aids

This collection reflects the life work of Dr. Jane Claire Dirks-Edmunds, a student and professor of Linfield College. A dedicated and scrupulous woman, the majority of the collection consists of her research, teaching materials, and correspondence. The collection also includes research and correspondence by Dr. Jane Claire Dirks-Edmunds’s mentor, Dr. James A. Macnab.

Forest Diversity And Disturbance: Changing Influences And The Future Of Virginia’S Forests, Christine J. Small, James L. Chamberlain

Virginia Journal of Science

The Virginia landscape supports a remarkable diversity of forests, from maritime dune woodlands, swamp forests, and pine savannas of the Atlantic Coastal Plain, to post-agricultural pine-hardwood forests of the Piedmont, to mixed oak, mesophytic, northern hardwood, and high elevation spruce-fir forests across three mountain provinces in western parts of the state. Virginia’s forests also have been profoundly shaped by disturbance. Chestnut blight, hemlock woolly adelgid, emerald ash borer, and other pests have caused declines or functional extirpation of foundation species. Invasive plants like multiflora rose, Oriental bittersweet, and Japanese stiltgrass threaten both disturbed and intact forests. Oaks and other fire-dependent …

Feasibility And Informative Value Of Environmental Sample Collection In The National Children's Vanguard Study, Elizabeth Barksdale Boyle, Nicole C. Deziel, Bonny L. Specker, Scott Collingwood, Clifford P. Weisel, David J. Wright, Michael Dellarco

Ethel Austin Martin Program Publications

Background: Birth cohort studies provide the opportunity to advance understanding of the impact of environmental factors on childhood health and development through prospective collection of environmental samples. Methods: We evaluated the feasibility and informative value of the environmental sample collection methodology in the initial pilot phase of the National Children's Study, a planned U.S. environmental birth cohort study. Environmental samples were collected from January 2009–September 2010 at up to three home visits: pre-pregnancy (n¼306), pregnancy (n¼807), and 6-months postnatal (n¼117). Collections included air for particulate matter r2.5 mm (PM2.5), nitrogen dioxide, ozone, volatile organic compounds (VOCs), and carbonyls; vacuum dust …

Flow Regime Classification And Hydrological Characterization: A Case Study Of Ethiopian Rivers, Belete Berhanu, Yilma Seleshi, Solomon S. Demisse, Assefa M. Melesse

Department of Earth and Environment

The spatiotemporal variability of a stream flow due to the complex interaction of catchment attributes and rainfall induce complexity in hydrology. Researchers have been trying to address this complexity with a number of approaches; river flow regime is one of them. The flow regime can be quantified by means of hydrological indices characterizing five components: magnitude, frequency, duration, timing, and rate of change of flow. Similarly, this study aimed to understand the flow variability of Ethiopian Rivers using the observed daily flow data from 208 gauging stations in the country. With this process, the Hierarchical Ward Clustering method was implemented …

Localized Ecological And Educational Effects Of Environmental Service-Learning In Portland, Oregon, Steven Matthew Braun

Dissertations and Theses

Environmental service-learning is an intentional educational experience(s) wherein learners engage in meaningful activities designed to serve the environment. Environmental service-learning activities vary according to their learning and service goals and include ecomanagement, persuasion, legal action, economic action and political action. The purpose of this mixed methods research was to explore the ecological and educational impacts of grades 6-12 environmental education, with special attention to environmental service-learning throughout Portland, Oregon.

Ecological impacts considered restoration and conservation outcomes of several environmental service-learning programs including plant communities, soils, litter removal and trail maintenance. Educational outcomes considered aspects of environmental literacy including locus of …

Mate Replacement And Alloparental Care In Ferruginous Hawk, Shubham Datta, Will M. Inselman, Jonathan A. Jenks, Kent Jensen, Christopher C. Swanson, Robert W. Klaver, Indrani Sasmal, Troy W. Grovenburg

Natural Resource Management Faculty Publications

Alloparental care (i.e., care for unrelated offspring) has been documented in various avian species (Maxson 1978, Smith et al. 1996, Tella et al. 1997, Lislevand et al. 2001, Literak and Mraz 2011). A male replacement mate that encounters existing broods has options, which include alloparental care or infanticide. Infanticide may be beneficial in some species (Rohwer 1986, Kermott et al. 1990), but in long-lived avian species, like the ferruginous hawk (Buteo regalis) that do not renest within a season, infanticide might be detrimental. Adoption and rearing success likely provide direct evidence of competence of replacement mates as potential parents for …

Acute Toxicity Of Β-N-Methylamino-L-Alanine (Bmaa) To Fathead Minnow (Pimephales Promelas) And Zebrafish (Danio Rerio), Jiayi Wang

School of Natural Resources: Dissertations, Theses, and Student Research

β-N-methylamino-L-alanine (BMAA) is a neurotoxic amino acid produced by most species of cyanobacteria. Exposure to BMAA has been hypothesized as a cause of ALS and possibly Parkinson’s and Alzheimer’s diseases for several decades. Both in vitro and in vivo experiments revealed that exposure to elevated concentrations of BMAA can damage motor neurons and cause motor dysfunctions. However, the exact mechanism of BMAA-induced neurotoxicity has not been well understood.

Based on the available literature and in spite of its water-soluble and non-protein nature, BMAA appears to be able to bioaccumulate in organisms. The ubiquity of cyanobacteria and the potential for bioaccumulation …

Combining And Aggregating Environmental Data For Status And Trend Assessments: Challenges And Approaches, Kathleen G. Maas-Hebner, Michael Harte, Nancy Molina, Robert M. Hughes, Carl B. Schreck, J. Alan Yeakley

Environmental Science and Management Faculty Publications and Presentations

Increasingly, natural resource management agencies and nongovernmental organizations are sharing monitoring data across geographic and jurisdictional boundaries. Doing so improves their abilities to assess local-, regional-, and landscape-level environmental conditions, particularly status and trends, and to improve their ability to make short-and long-term management decisions. Status monitoring assesses the current condition of a population or environmental condition across an area. Monitoring for trends aims at monitoring changes in populations or environmental condition through time. We wrote this paper to inform agency and nongovernmental organization managers, analysts, and consultants regarding the kinds of environmental data that can be combined with suitable …

The Contribution Of Indigenous Ecological Knowledge In Conservation Of Enguserosambu Community Forest, Tanzania, Agnes Sirima

All Dissertations

Community managed forests constitute a significant proportion of the world's forests, however, little is known regarding their condition or the details of how they are managed. Documented benefits of community managed forest include poverty alleviation and in some places a decrease in the rate of deforestation. Although some community based forests do not satisfy the IUCN definition of a protected areas, they provide valuable long term sustainability of forest products and many are also rich in biodiversity and support landscape conservation strategies. Forests are also home to many cultures including the indigenous people. Indigenous communities surrounding forest areas and other …

Development Modeling Of Lucilia Sericata (Diptera: Calliphoridae), Amanda Roe, Leon G. Higley

School of Natural Resources: Faculty Publications

The relationship between insect development and temperature has been well established and has a wide range of uses, including the use of blow flies for postmortem (PMI) interval estimations in death investigations. To use insects in estimating PMI, we must be able to determine the insect age at the time of discovery and backtrack to time of oviposition. Unfortunately, existing development models of forensically important insects are only linear approximations and do not take into account the curvilinear properties experienced at extreme temperatures. A series of experiments were conducted with Lucilia sericata, a forensically important blow fly species, that met …

Microbial Iron Mats At The Mid-Atlantic Ridge And Evidence That Zetaproteobacteria May Be Restricted To Iron-Oxidizing Marine Systems, Jarrod J. Scott, John A. Breier, George W. Luther Iii, David Emerson

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Chemolithoautotrophic iron-oxidizing bacteria play an essential role in the global iron cycle. Thus far, the majority of marine iron-oxidizing bacteria have been identified as Zetaproteobacteria, a novel class within the phylum Proteobacteria. Marine iron-oxidizing microbial communities have been found associated with volcanically active seamounts, crustal spreading centers, and coastal waters. However, little is known about the presence and diversity of iron-oxidizing communities at hydrothermal systems along the slow crustal spreading center of the Mid-Atlantic Ridge. From October to November 2012, samples were collected from rust-colored mats at three well-known hydrothermal vent systems on the Mid-Atlantic Ridge (Rainbow, Trans-Atlantic Geotraverse, and …

Maine's Sustainability Science Initiative, Michael Eckardt, Vicki Nemeth, David Hart

University of Maine Office of Research Administration: Grant Reports

Goals: Maine's Sustainability Science Initiative (SSI) seeks to catalyze and expand the state's interdisciplinary research capacity for understanding the coupled dynamics of social-ecological systems (SES) and determining how such knowledge can best inform stakeholders and their decision-making processes. The core SSI objective is to create a new statewide Center for Sustainability Solutions (CSS) where place-based systems research, knowledge to action focus, and strong stakeholder partnerships will serve as a testbed for developing solutions to sustainable development challenges in and beyond Maine. The research focuses on three interacting drivers of landscape change (urbanization, forest ecosystem management, and climate change) that affect …

Restoration Of Headwater And Coastal Fens In The Lake Superior Basin Of Upper Michigan, James A. Bess

Dissertations, Master's Theses and Master's Reports - Open

In 2009, research projects were initiated at Michigan Technological University to develop restoration techniques for headwater fens and coastal wetlands in the southern Lake Superior Basin in Michigan’s Upper Peninsula. The primary focus of these was to quantify the efficacy of using locally collected seeds as a technique for wetland restoration. Two primary sites were selected, the Sleeper Lake Fen complex in Luce County and the Portage Waterway-Keweenaw Bay region of Lake Superior in Baraga and Houghton Counties. At the Sleeper Lake site, a combination of heavy machinery, seeding and mulch application was used to restore a 1.6 km ditch …

Gentrified Sustainability: Inequitable Development And Seattle’S Skewed Riskscape, Troy D. Abel, Jonah White

College of the Environment on the Peninsulas Publications

This paper examines the tensions of sustainable development in Seattle, Washington, a commonly recognised urban environmental leader. Drawing on the perspective of sustainability as a conflicted process, this research expected a negative relationship between gentrification and environmental justice when affluent residents outcompete less affluent ones for neighbourhoods with fewer environmental hazards. The methods combine geographic cluster analysis and longitudinal air toxic emission comparisons to analyse socioeconomic changes in Seattle Census block-groups between 1990, 2000, and 2009 coupled with measures of relative potential risk and pollution volume. The property and development conflicts embedded within sustainability lead to pollution exposure risk and …

The Uncertain Climate Footprint Of Wetlands Under Human Pressure, Ana Maria Roxana Petrescu, Annalea Lohila, Juha-Pekka Tuovinen, Dennis D. Baldocchi, Ankur R. Desai, Nigel T. Roulet, Timo Vesala, Albertus Johannes Dolman, Walter C. Oechel, Barbara Marcolla, Thomas Friborg, Janne Rinne, Jaclyn Hatala Matthes, Lutz Merbold, Ana Meijide, Gerard Kiely, Matteo Sottocornola, Torsten Sachs, Donatella Zona, Andrej Varlagin, Derrick Y.F. Lai, Elmar Veenendaal, Frans-Jan W. Parmentier, Ute Skiba, Magnus Land, Arjan Hensen, Jacobus Van Huissteden, Lawrence B. Flanagan, Narasinha J. Shurpali, Thomas Grünwald, Elyn R. Humphreys, Marcin Jackowicz-Korczynski, Mika A. Aurela, Tuomas Laurila, Carsten Grüning, Chiara A.R. Corradi, Arina P. Schrier-Uijl, Torben R. Christensen, Mikkel P. Tamstorf, Mikhail Mastepanov, Pertti J. Martikainen, Shashi Verma, Christian Bernhofer, Alessandro Cescatti

School of Natural Resources: Faculty Publications

Significant climate risks are associated with a positive carbon–temperature feedback in northern latitude carbon-rich ecosystems,making an accurate analysis of human impacts on the net greenhouse gas balance of wetlands a priority. Here, we provide a coherent assessment of the climate footprint of a network of wetland sites based on simultaneous and quasi-continuous ecosystem observations of CO₂ and CH₄ fluxes. Experimental areas are located both in natural and in managed wetlands and cover a wide range of climatic regions, ecosystem types, and management practices. Based on direct observations we predict that sustained CH₄ emissions in natural ecosystems are …

Mercury Speciation, Retention, And Abundance Of Genes Involved With Mercury Methylation In Fertilized Salt Marsh Sediments, Caroline Collins

Biology Honors Papers

Mercury (Hg) is a global pollutant which exists in both aquatic and terrestrial systems in three main forms including elemental Hg, ionic mercury, and methyl mercury, (MeHg), and Hg cycling plays an important role in ecosystems. Great Sippewisset Marsh, (GSM) in Falmouth MA has been chronically treated with fertilizer that contains heavy metals such as Hg in varying concentrations since the early 1970s and provides for an excellent location to study Hg contamination. The overall goal of this study is to analyze the key geochemical and microbial conditions that lead to MeHg production in the presence of the applied fertilizer. …

Quantifying The Adaptive Cycle, David G. Angeler, Craig R. Allen, Ahjond S. Garmestani, Lance H. Gunderson

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

The adaptive cycle was proposed as a conceptual model to portray patterns of change in complex systems. Despite the model having potential for elucidating change across systems, it has been used mainly as a metaphor, describing system dynamics qualitatively. We use a quantitative approach for testing premises (reorganisation, conservatism, adaptation) in the adaptive cycle, using Baltic Sea phytoplankton communities as an example of such complex system dynamics. Phytoplankton organizes in recurring spring and summer blooms, a well-established paradigm in planktology and succession theory, with characteristic temporal trajectories during blooms that may be consistent with adaptive cycle phases. We used long-term …

Site-Specific Habitat And Landscape Associations Of Rusty Blackbirds Wintering In Louisiana, Sinead Mary Borchert

LSU Master's Theses

The Rusty Blackbird (Euphagus carolinus) has gained notoriety in recent years as one of the fastest declining North American bird species, with a global population loss of as much as 95%. Causes of the decline are not completely understood, but the high rate of forested wetland change in the southeastern United States suggests that wintering habitat degradation may be a primary driver. To better inform management on critical wintering grounds, I surveyed 68 sites in Louisiana where Rusty Blackbirds had been known to occur to address how occupancy changes with habitat type and colonization and extinction rates vary with ground …

Estimating Relative Sea-Level Rise And Submergence Potential At A Coastal Wetland, Donald R. Cahoon

United States Geological Survey: Staff Publications

A tide gauge records a combined signal of the vertical change (positive or negative) in the level of both the sea and the land to which the gauge is affixed; or relative sealevel change, which is typically referred to as relative sea-level rise (RSLR). Complicating this situation, coastal wetlands exhibit dynamic surface elevation change (both positive and negative), as revealed by surface elevation table (SET) measurements, that is not recorded at tide gauges. Because the usefulness of RSLR is in the ability to tie the change in sea level to the local topography, it is important that RSLR be calculated …

Sea Level And Turbidity Controls On Mangrove Soil Surface Elevation Change, Catherine E. Lovelock, Maria Fernanda Adame, Vicki Bennion, Matthew Hayes, Ruth Reef, Nadia Santini, Donald R. Cahoon

United States Geological Survey: Staff Publications

Increases in sea level are a threat to seaward fringing mangrove forests if levels of inundation exceed the physiological tolerance of the trees; however, tidal wetlands can keep pace with sea level rise if soil surface elevations can increase at the same pace as sea level rise. Sediment accretion on the soil surface and belowground production of roots are proposed to increase with increasing sea level, enabling intertidal habitats to maintain their position relative to mean sea level, but there are few tests of these predictions in mangrove forests. Here we used variation in sea level and the availability of …