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Post-Fire Changes In Interior Alaska's Vegetation Composition, Jannike E. Allen

University Honors Theses

Global warming is altering the fire regime of interior Alaska, which may have cascading effects on the prevalence of forest types and species dominance across this region. Our objective was to investigate the relationship between vegetation composition and fire in the boreal forest of interior Alaska. We utilized data from over 700 plots sampled across the landscape designated as the Tanana region by the US Forest Service for Forest Inventory Analysis (FIA), as well as fire history records. We compared biomass and stem density of conifer and hardwood forest types, as well as individual tree species, across a gradient of …

Sandy Buck '78: Seeing Light Amidst The Gloom, Gerry Boyle

Colby Magazine

"If you look at the macro you could come to a grinding halt and throw your hand up. But when you look at the local, and even state and regional levels, there are reasons for hope." -Sandy Buck '78

Assessing Drought Vegetation Dynamics At The Landscape Scale In Semiarid Grass- And Shrubland Using Mesma, Rowan Converse

Geography ETDs

New Mexico experienced substantial impacts of regional-scale drought from 2011-2014. Global climate change may make such events a new normal for the southwest: drought events are expected to increase in both frequency and severity over the coming century. While semiarid grasslands recover quickly from short-term drought, the cumulative impacts of climate change may reduce the resiliency of these systems over time. Remote sensing methods can allow efficient and cost-effective comparison of ecosystem recovery from drought events over time using long-running imaging systems like Landsat. We investigate the efficacy of using multi-endmember spectral mixture analysis (MESMA) to quantify the impacts of …

Space And Depth-Resolved Naturally Occurring Toxic Groundwater Species In Bangladesh And Rwanda: Origination And Risk Analysis, Kenneth Hamilton

Civil and Environmental Engineering Theses and Dissertations

Access to safe potable water is a necessity for all. Groundwater is a commonly relied upon drinking water source for many areas around the world. This is especially true for communities in high density, rural settings. Such is the case for populations near Cox’s Bazaar, Bangladesh, and in the Bugesera region of Rwanda. Sediment and groundwater contamination, through toxic dissolved species, represents a significant public health risk to exposed populations. Tropical soils, such as the soil profiles in Bangladesh and Rwanda, often contain higher concentrations of heavy metals (Rieuwerts, 2007). Additionally, nitrate from fertilizers, are widely used on the soils …

Ceramic Water Filter For Point-Of-Use Water Treatment In Developing Countries: Principles, Challenges And Opportunities, Haiyan Yang, Shangping Xu, Derek E. Chitwood, Yin Wang

Faculty Work Comprehensive List

Drinking water source contamination poses a great threat to human health in developing countries. Point-of-use (POU) water treatment techniques, which improve drinking water quality at the household level, offer an affordable and convenient way to obtain safe drinking water and thus can reduce the outbreaks of waterborne diseases. Ceramic water filters (CWFs), fabricated from locally sourced materials and manufactured by local labor, are one of the most socially acceptable POU water treatment technologies because of their effectiveness, low-cost and ease of use. This review concisely summarizes the critical factors that influence the performance of CWFs, including (1) CWF manufacturing process …

Impacts Of Medusahead (Elymus Caput-Medusae L.) Management On Plant Communities In California’S Valley Grasslands, Nicole Carpenter

Master's Projects and Capstones

California’s valley grasslands are one of the most invaded ecosystems in the state. It is estimated that valley grasslands contain between 90 to 99% cover of non-native plants. The most recent wave of invasive plants has included medusahead (Elymus caput-medusae L.). Medusahead is an annual grass that matures two to four weeks later than most other grasses. Management of medusahead includes the use of herbicides, targeted grazing, prescribed burns, and mechanical control. The primary focus of most studies on the use of these management methods is on the control of medusahead rather than the impacts on non-target plants. This …

Effects Of Land Use On Riparian Corridors In Sonoma County, Marina Davies

Master's Projects and Capstones

Riparian corridor protection through zoning ordinances is a common best management practice to protect riparian ecosystems and function. These zoning ordinances protect riparian ecosystems by establishing setback distances where land use activities are prohibited. While management of protected riparian corridors are widely studied, recommendations for riparian corridor width vary and are often site specific. The variability of corridor widths presents a challenge to riparian corridor implementation, in addition to balancing economic needs with natural resource protection. This study evaluates the effects of land use on riparian corridors and compares the Riparian Corridor Combining Zone ordinance in Sonoma County to other …

Photographic Validation Of Target Versus Nontarget Take Of Brown Treesnake Baits, Shane R. Siers, Aaron B. Shiels, Cynthia G. Payne, Francinem M. Chlarson, Craig S. Clark, Stephen M. Mosher

United States Department of Agriculture Wildlife Services: Staff Publications

Use of toxic baits or other tools for managing nuisance species must ensure that the species of interest is adequately targeted while exposure to nontarget species is minimized. Nontarget takes of acetaminophen‐laced baits for control of invasive brown treesnakes (Boiga irregularis) on Guam may put those animals at risk of lethal intoxication and render the bait unavailable to the intended target species. We used wildlife cameras to identify species removing toxic and nontoxic baits from brown treesnake bait stations designed to exclude nontarget taxa in 2015 and 2016. Throughout various sites and habitat types, and balanced by season (wet vs. …

Time Allocation To Resources By Three Species Of Rats (Rattus Spp.) In A Radial Arm Maze, Gary Witmer, Nathan P. Snow, Rachael S. Moulton

United States Department of Agriculture Wildlife Services: Staff Publications

Context. Introduced rats (Rattus spp.) can pose a serious threat to native flora and fauna, especially on islands where most species have evolved in the absence of terrestrial predators. Effective detection and eradication methods for introduced rats are essential to the maintenance of insular ecosystem integrity. Thus, it is important to better understand the behaviour of rats when they first arrive in a new setting.

Aims. To determine whether rats would find some novel stimuli to be significantly more attractive than other novel stimuli.

Methods. An eight-arm radial maze was used to study the behaviour of three species of Rattus …

Interactions With Humans Shape Coyote Responses To Hazing, Julie K. Young, Edd Hammill, Stewart W. Breck

United States Department of Agriculture Wildlife Services: Staff Publications

Medium and large carnivores coexist with people in urban areas globally, occasionally resulting in

negative interactions that prompt questions about how to reduce human-wildlife conflict. Hazing,

i.e., scaring wildlife, is frequently promoted as an important non-lethal means for urbanites to reduce

conflict but there is limited scientific evidence for its efficacy. We used a population of captive coyotes (Canis latrans) to simulate urban human-coyote interactions and subsequent effects of hazing on coyote behavior. Past experiences with humans significantly affected the number of times a coyoteapproached a human to necessitate hazing. coyotes that had been hand fed by adults had to …

Hawaii As A Microcosm: Advancing The Science And Practice Of Managing Introduced And Invasive Species, Liba Pejchar, Christopher A. Lepczyk, Jean E. Fantle-Lepczyk, Steven C. Hess, M. Tracy Johnson, Christina R. Leopold, Michael Marchetti, Katherine M. Mcclure, Aaron B. Shiels

United States Department of Agriculture Wildlife Services: Staff Publications

Invasive species are a leading driver of global change, with consequences for biodiversity and society. Because of extraordinary rates of endemism, introduction, and extinction, Hawaii offers a rich platform for exploring the cross-disciplinary challenges of managing invasive species in a dynamic world. We highlight key successes and shortcomings to share lessons learned and inspire innovation and action in and beyond the archipelago. We then discuss thematic challenges and opportunities of broad relevance to invaded ecosystems and human communities. Important research needs and possible actions include eradicating mammals from mainland island sanctuaries, assessing hidden threats from poorly known introduced species, harnessing …

Deciphering Interactions Between White-Tailed Deer And Approaching Vehicle, Morgan Pfeiffer, Raymond B. Iglay, Thomas W. Seamans, Bradley F. Blackwell, Travis L. Devault

United States Department of Agriculture Wildlife Services: Staff Publications

Deer-vehicle collisions are a major transportation hazard, but factors affecting deer escape decision-making in response to vehicle approach remain poorly characterized. We made opportunistic observations of deer response to vehicle approach during daylight hours on a restricted- access facility in Ohio, USA (vehicle speeds were ≤64 km/h). We hypothesized that animal proximity to the road, group size, vehicle approach, and ambient conditions would affect perceived risk by white-tailed deer (Odocoileus virginianus) to vehicle approach, as measured by flight-initiation distance (FID). We constructed a priori models for FID, as well as road-crossing behavior. Deer responses were variable and did not demonstrate …

A Review Of The Methods And Metrics In Research, Implementation, And Management Of Integrated Multi-Trophic Aquaculture, Cassandra Erickson

Master's Projects and Capstones

As seafood demand rises with the growing population, methods of providing sustainable and reliable protein are needed. Wild fishery stocks have decreased so aquaculture is seen as the way to meet these growing demands. The aquaculture industry has continued to grow 8.3% every year since 1970 primarily through using intensive cultivation of a single species creating negative effects on the marine environment. An increase in nutrients from these intensive cultivations can lead to eutrophication, a decrease in oxygen, and alter the ecosystem structure and biodiversity. Integrated multi-trophic aquaculture (IMTA) aims to offset the increased input of nutrients through fish farming …

A New Species Of Chromis (Teleostei: Pomacentridae) From Mesophotic Coral Ecosystems Of Rapa Nui (Easter Island) And Salas Y Gomez, Chile, Bart Shepard, Hudson T. Pinheiro, Tyler A. Y. Phelps, Erin E. Easton, Alejandro Perez-Matus, Luiz A. Rocha

School of Earth, Environmental, & Marine Sciences Faculty Publications

A new species of Chromis (Teleostei: Pomacentridae) is described from three specimens collected at 90 m depth in a mesophotic coral ecosystem at Rapa Nui, Chile. Chromis mamatapara, new species, can be distinguished from its congeners by the following combination of characters: dorsal-fin rays XIV,13–14; pectoral-fin rays 18–19, third from top of fin longest; tubed lateral-line scales 18; total gill rakers on first arch 30–32; vertebrae 11þ15; and by coloration of living specimens, especially the presence of a single, pronounced, white spot, roughly the same diameter as the orbit, located where the posterior base of the dorsal fin intersects the …

Evaluating The Success Of Compensatory Wetland Mitigation In The California Coastal Zone, Tommy Alexander

Master's Projects and Capstones

Compensatory mitigation is a practice whereby a government agency requires the creation, restoration, enhancement, or preservation of ecological resources to offset unavoidable adverse impacts to environmentally sensitive habitat caused by some form of development. Compensatory wetland mitigation programs have slowed the rate of wetland loss in California and elsewhere, but they have largely failed to offset impacts with a sufficient amount of functional mitigation acreage. In California, more than 90% of the state’s historical wetlands have been drained, diked, filled, or dredged over the past 100 years. This report evaluates the success of compensatory wetland mitigation required by the California …

Bull Kelp (Nereocystic Lutkeana) Restoration And Management In Northern California, Olivia Johnson

Master's Projects and Capstones

Northern California’s coastal marine ecosystems support one of the most productive and biodiverse habitats on the planet. Bull kelp forests (Nereocystic lutkeana) form habitats for an abundance of marine mammals, sea bird, fish, and invertebrates. In recent years, compounding ecological and climatic factors have disrupted the balance of the bull kelp forests and led to an unprecedented loss of bull kelp biomass and canopy cover. These areas that are typically teeming with marine life have shifted into a stable state of sea urchin barrens due to over grazing of bull kelp by purple sea urchins (Strongylocentrotus pupuratus). These sea urchin …

Soil Microbes Trade-Off Biogeochemical Cycling For Stress Tolerance Traits In Response To Year-Round Climate Change, Maria O. Garcia, Pamela H. Templer, Patrick O. Sorensen, Rebecca Sanders-Demott, Peter M. Groffman, Jennifer M. Bhatnagar

Advanced Science Research Center

Winter air temperatures are rising faster than summer air temperatures in high-latitude forests, increasing the frequency of soil freeze/thaw events in winter. To determine how climate warming and soil freeze/thaw cycles affect soil microbial communities and the ecosystem processes they drive, we leveraged the Climate Change across Seasons Experiment (CCASE) at the Hubbard Brook Experimental Forest in the northeastern United States, where replicate field plots receive one of three climate treatments: warming (+5°C above ambient in the growing season), warming in the growing season + winter freeze/thaw cycles (+5°C above ambient +4 freeze/thaw cycles during winter), and no treatment. Soil …

Evaluating Moose Alces Alces Population Response To Infestation Level Of Winter Ticks Dermacentor Albipictus, Daniel D. Ellingwood, Peter J. Pekins, Henry Jones, Anthony R. Musante

United States Department of Agriculture Wildlife Services: Staff Publications

Many wildlife populations are experiencing a variety of environmental pressures due to the direct and indirect consequences of a changing climate. In the northeast, USA, moose Alces alces are declining in large part because of the increasing parasitism by winter tick Dermacentor albipictus, facilitated by high host density and optimal environmental conditions. To test this hypothesis, and better understand the influence of this interaction on the stability of the regional population, we constructed a population viability model using data collected through comprehensive survival and productivity studies in 2002–2005 and 2014–2018 in northern New Hampshire. Years of heavy tick infestation (epizootics) …

Assessing The Potential For Greater Solar Development In West Texas, Usa, Dale D. Devitt, M. H. Young, J. P. Pierre

Life Sciences Faculty Research

As population and economies continue to grow on a global scale, so too does the demand for energy. To improve reliability and independence of energy supplies, the U.S. and many other countries are seeking internally-sourced renewable energy; solar is one such renewable-energy source that meets these criteria. However, all energy sources exert some environmental impacts. In the case of solar, direct impacts stem mostly from alteration of land needed to host infrastructure. Understanding the environmental upside and downside potential of solar energy systems allows a more comprehensive, side-by-side comparison with different energy sources. In this article, we focus on the …

Spillover Of Sars-Cov-2 Into Novel Wild Hosts In North America: A Conceptual Model For Perpetuation Of The Pathogen, Alan B. Franklin, Sarah N. Bevins

United States Department of Agriculture Wildlife Services: Staff Publications

There is evidence that the current outbreak of the novel coronavirus SARS-CoV-2, which causes COVID-19, is of animal origin. As with a number of zoonotic pathogens, there is a risk of spillover into novel hosts. Here, we propose a hypothesized conceptual model that illustrates the mechanism whereby the SARS-CoV-2 could spillover from infected humans to naive wildlife hosts in North America. This proposed model is premised on transmission of SARS-CoV-2 from human feces through municipal wastewater treatment plants into the natural aquatic environment where potential wildlife hosts become infected. We use the existing literature on human coronaviruses, including SARS CoV, …

Synergistic Use Of Remote Sensing And Modeling For Estimating Net Primary Productivity In The Red Sea With Vgpm, Eppley-Vgpm, And Cbpm Models Intercomparison, Wenzhao Li, Surya Prakash Tiwari, Hesham El-Askary, Mohamed Ali Qurban, Vassilis Amiridis, K. P. Manikandan, Michael J. Garay, Olga V. Kalashnikova, Thomas C. Piechota, Daniele C. Struppa

Mathematics, Physics, and Computer Science Faculty Articles and Research

Primary productivity (PP) has been recently investigated using remote sensing-based models over quite limited geographical areas of the Red Sea. This work sheds light on how phytoplankton and primary production would react to the effects of global warming in the extreme environment of the Red Sea and, hence, illuminates how similar regions may behave in the context of climate variability. study focuses on using satellite observations to conduct an intercomparison of three net primary production (NPP) models--the vertically generalized production model (VGPM), the Eppley-VGPM, and the carbon-based production model (CbPM)--produced over the Red Sea domain for the 1998-2018 time period. …

The Pantropical Response Of Soil Moisture To El Niño, Kurt C. Solander, Brent D. Newman, Alessandro Carloca De Araujo, Holly R. Barnard, Z. Carter Berry, Damien Bonal, Mario Bretfeld, Benoit Burban, Luiz Antonio Candido, Rolando Celleri, Jeffery Q. Chambers, Bradley O. Christoffersen

School of Earth, Environmental, & Marine Sciences Faculty Publications

The 2015–2016 El Niño event ranks as one of the most severe on record in terms of the magnitude and extent of sea surface temperature (SST) anomalies generated in the tropical Pacific Ocean. Corresponding global impacts on the climate were expected to rival, or even surpass, those of the 1997–1998 severe El Niño event, which had SST anomalies that were similar in size. However, the 2015–2016 event failed to meet expectations for hydrologic change in many areas, including those expected to receive well above normal precipitation. To better understand how climate anomalies during an El Niño event impact soil moisture, …

Development Of A Modified Floristic Quality Index As A Rapid Habitat Assessment Method In The Northern Everglades, Rebakah E. Gibble, Donatto D. Surratt

United States National Park Service: Publications

Floristic quality assessments (FQA) using floristic quality indices (FQIs) are useful tools for assessing and comparing vegetation communities and related habitat condition. However, intensive vegetation surveys requiring significant time and technical expertise are necessary, which limits the use of FQIs in environmental monitoring programs. This study modified standard FQI methods to develop a rapid assessment method for characterizing and modeling change in wetland habitat condition in the northern Everglades. Method modifications include limiting vegetation surveys to a subset of taxa selected as indicators of impact and eliminating richness and/or abundance factors from the equation. These modifications reduce the amount of …

Development Of Methods To Track Oyster Movement Under Field Conditions In North Inlet Estuary, South Carolina, Alyssa M. Leclaire

Honors Theses

Eastern oyster (Crassostrea virginica) reefs provide important habitat structure and ecosystem services in saltmarsh tidal creek estuaries. Reef persistence depends on growth of resident individuals and regular recruitment to maintain suitable shell substrate. Boat wakes potentially physically displace oyster clumps. The objective of this research was to develop methods to track oyster clump position and biomass on two natural fringing oyster reefs in North Inlet estuary, South Carolina. Boat traffic (number of boats making wakes per day), oyster clump displacement (cm/d) over time, oyster biomass (g dry tissue), and condition index (biomass/g dry shell weight) were quantified from …

Statistical Analysis Of Land Cover Conversion Trends In Northwest Ohio, Chaska Mcgowan

Honors Projects

Agricultural land in the U.S. is abundant but not infinite. Change in cropland impacts national and local economies and the natural environment. The Black Swamp Conservancy (BSC), a non-profit land trust in Perrysburg, Ohio, is committed to preserving agricultural and natural lands in the Northwest Ohio region for future generations. This project was designed in collaboration with the BSC to illustrate the spatial distribution of land cover change within their sixteen-county service area in Northwest Ohio and to find a list of factors associated with land cover change in the region. The primary data source was the National Land Cover …

Public Perspectives And Media Reporting Of Wolf Reintroduction In Colorado, Rebecca Niemiec, Richard E.W. Berl, Mireille Gonzalez, Tara Teel, Cassiopeia Camara, Matthew Collins, Jonathan Salerno, Kevin Crooks, Courtney Schultz, Stewart Breck, Dana Hoag

United States Department of Agriculture Wildlife Services: Staff Publications

In the state of Colorado, a citizen ballot initiative to reintroduce gray wolves (Canis lupus) is eliciting polarization and conflict among multiple stakeholder and interest groups. Given this complex social landscape, we examined the social context surrounding wolf reintroduction in Colorado as of 2019. We used an online survey of 734 Coloradans representative in terms of age and gender, and we sampled from different regions across the state, to examine public beliefs and attitudes related to wolf reintroduction and various wolf management options. We also conducted a content analysis of media coverage on potential wolf reintroduction in 10 major daily …

Effects Of Warming On Decomposition Of Submerged Plant Litter And Associated Microorganisms In Streamside Channels, Kaity Ackerman

Electronic Theses and Dissertations

Surface air temperatures are predicted to increase in the near future, which will likely affect microbial activity and carbon flow in stream ecosystems. I performed an experiment in streamside channels at Coweeta Hydrological Laboratory, NC to assess responses of litter-associated microorganisms to moderate increases in water temperature (5 levels, ambient to +4°C). The objectives of the experiment were to determine: (1) if there are differences in the magnitude of responses to temperature among various microbial parameters and (2) whether microbial responses to temperature vary among plant litter of different carbon quality. Thus, I measured litter decomposition rate, fungal biomass (ergosterol), …

Shifting Public Perception: Climate Change Means Living With Fire And Smoke, Robert Froembling

Seattle Journal of Technology, Environmental, & Innovation Law

The urgency to prepare for the climate crisis has never been greater. We are currently living in the sixth mass extinction and the effects are only going to accelerate. We will inherit more wildfires, larger wildfires, and more frequent wildfires.

This piece is not meant to stoke fear in its readers or be depressing, but to shift public perception on what our future holds by evaluating the laws and science presented to us. This piece will look at regional and federal regulations and assess the increased rate of forest fires and the grave public health concerns from stagnant smoke specifically …

Ecosystem Services Of Urban Tree Canopy For The Mitigation Of Climate Change: Measuring Carbon Sequestration And Understory Temperature Reduction Of Knoxville’S Urban Forest, Tyler Hounshell

Pursuit - The Journal of Undergraduate Research at The University of Tennessee

In the future, the city of Knoxville, Tennessee will be impacted by climate warming due to anthropogenic climate change. Yet, the ecosystem services provided by urban tree canopy in Knoxville’s urban forest can help mitigate the effects of climate warming. In addition to improving air quality, regulating water flow, and reducing noise pollution, Knoxville’s urban forest serves as a carbon sink and sequesters carbon dioxide on an annual basis. Utilizing methods for calculating carbon sequestration by trees in urban and suburban settings developed by the U.S. Energy Information Administration, the sequestration potential and its uncertainty is calculated until the year …

Fire Monitoring Handbook

United States National Park Service: Publications

Fire is a powerful and enduring force that has had, and will continue to have, a profound influence on National Park Service (NPS) lands. Fire management decisions within the National Park Service require information on fire behavior and on the effects of fire on park resources. With good reason, the public is holding park management increasingly accountable, especially in the area of fire management. Federal and state agencies are instituting progressively more stringent guidelines for burning, monitoring, and evaluation. The impetus behind these guidelines and the purpose of this handbook are to ensure that management objectives are being met, to …