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Publication Tree Protection for Street Corridor Development in Massachusetts(2024-09) Mahoney, DeliaMassachusetts is home to millions of trees located not only in forests, but along streets and roadways across urban, suburban, and rural environments. The people living in these communities rely on street trees to provide necessary ecosystem services, such as shading and cooling, or stormwater mitigation. When street trees are damaged during construction projects or other infrastructure development work, communities lose out on these services. Street trees and urban forests are often an afterthought in the construction process and may be severely damaged during construction without proper protection and preservation measures. As Massachusetts develops comprehensive capital improvement projects as part of the Complete Streets initiative, the necessary redevelopment of pedestrian and cycling pathways state- wide will impact the existing urban forest ecosystem. The Massachusetts Department of Transportation (MassDOT) oversees many of the projects involving roadways and transportation corridors in the Commonwealth. This organization strives to lead by example by evaluating and updating their existing guidelines to reflect current industry best practices. MassDOT is seeking a cohesive collection and assessment of industry approaches to ensure that urban forest health and preservation remain a priority in upcoming improvement projects. This report contains an assessment of current project development guidelines used by MassDOT and evaluates the existing standards in accordance with insight from contemporary sources. We assessed major themes including soil compaction and root zone preservation, awareness on the construction site, and methods for successful reforestation following construction. Our first task was to review the relevant literature to determine the current state of best practices. The literature review focused on street tree preservation techniques during construction and development, as well as design alternatives and remediation strategies. Content surveyed included peer-reviewed research publications, technical documentation, and reference guides from other jurisdictions. The next step was the creation and distribution of a survey for professionals nationwide to assess the current status 10 of street tree preservation practices. Finally, the information gathered from both the literature review and the survey was synthesized and the existing MassDOT guidelines were evaluated in accordance with the research findings. At the time of writing, the existing resource for tree preservation and landscape design for MassDOT projects was an online compendium known as the Project Development and Design Guide (PDDG). Recommendations were made to update and improve the existing MassDOT PDDG to reflect current practices and new insight.Publication Quantifying the Impact of Introducing Confiscated Turtles with Disease or Deleterious Alleles into a Wild Population(2024-09) Tavarez-Jimenez, Ednita JGlobal biodiversity is imperiled by illegal wildlife trade. Illegal wildlife are confiscated by law enforcement, wildlife biologists, or other authorities, providing the opportunity to reintroduce these individuals back into the wild. However, with the reintroduction of confiscated animals back into the wild comes many risks and uncertainties of introducing disease and deleterious alleles to naive wild populations. Chapter 1 explores the advantages and challenges of translocations, alongside theoretical and empirical evidence on genetic and disease risk of these introductions. In chapter 2, I investigated the effects of introducing disease and deleterious alleles to wild turtle populations, focusing on the wood turtle (Glyptemys insculpta) as a case study due to their demand in the illegal wildlife trade. Using a population projection model, I parameterized the population matrix using a combination of literature review and data analysis. Calculating the deterministic and stochastic population growth rates, considering genetics and diseases risks, I projected population sizes in 20 years under a variety of scenarios of confiscated introduced turtles. Sensitivity analysis identifies parameters that had the largest impact on population growth rate. Based on my analysis, the stochastic and deterministic population growth rate indicated that the wood turtle population is declining when either disease or deleterious alleles are present. Concerns about introducing infected individuals into a population become important only when a substantial number of infected adults and individuals with deleterious alleles are introduced, and from my projections, once greater than 10 animals are introduced to a recipient population with 100 individuals, then the proportion of infected animals and individuals without deleterious alleles at the end of 20 years rapidly increases as the number of animals introduced increases. This was also evident in the projected population sizes in 20 years under a variety of different scenarios. Using a sensitivity analysis, I found that, adult survival probability had the largest positive effect on population growth rate. These findings highlight the importance of carefully evaluating the risks and uncertainties associated with reintroduction efforts, especially concerning disease and deleterious alleles. On a broader scale, this research enhances our understanding of the complex dynamics involved in repatriating confiscated wildlife and the associated risks of their reintroduction into wild populations.Publication Resident Perspectives on Tornado-Induced Canopy Loss and a Decade of Regrowth in Springfield, Massachusetts(2024-09) Powning, CandaceCity dwellers want and need trees in their home landscapes. Trees provide numerous ecosystem services and help to create a sense of place within built-up urban landscapes – and because of this, urban residents form connections with and dependencies on the trees around them, whether or not they are aware. When these trees that individuals and communities rely on are suddenly gone, their experience of their home landscapes can change dramatically. Within the context of a tornado that caused dramatic tree canopy loss in Springfield, Massachusetts in June of 2011, we investigated resident perspectives of tree loss in order to understand what they valued about trees; how their relationship with trees and their experience of their home landscape was altered as a result of the tornado; and how they experienced a post-tornado yard tree planting program and interacted with the stewardship of their new trees in an altered landscape. Knowing that qualitative, semi-structured research interviews are an effective way of gaining a deep and clear understanding of an individual’s values, experiences and perspectives, we elected to use this methodology as the core of this research. Firstly, we performed a literature review in order to understand how and why researchers in the field of urban forestry have been employing this methodology, and found that civilian (non-urban forestry practitioner) perspectives are less prevalent in qualitative urban forestry research, particularly in the Global North. This highlighted the importance of centering resident perspectives of tree loss and tree regrowth in the aftermath of the tornado, rather than urban forestry practitioner or decision maker perspectives. As weather events become increasingly frequent and severe, and tree loss continues to be a significant consequence of these severe weather events, it is necessary to understand how community members feel about this loss so that disaster recovery resources can be appropriately tailored to their needs.Publication Does Climate Change Initiate Migratory Tradeoffs that Influence Reproduction in a Long-distance Migratory Shorebird, the Hudsonian Godwit (Limosa Haemastica)?(2024-09) Puleo, LaurenClimate change induced shifts in resource phenology threatens to negatively impact migratory species that are unable to alter their migratory and reproductive timing accordingly. Yet, many long-distance migrants are not advancing their reproductive timing at the same rates as their migratory timing. Some long-distance migrants may only be able to alter their migratory timing through costly en route decisions, presenting individuals with a tradeoff between early arrival and arrival body condition. For species that exhibit mate fidelity and rapid clutch initiation, arriving to the breeding grounds in poor condition may affect sexes differently, constraining advances in reproductive timing. Little is known, however, about the potential sex-specific effects of climate change on migrants and how they may influence reproduction. Thus, I utilized long-term tracking data in combination with isotope analyses to investigate whether there is a tradeoff between arrival timing and body condition that influences reproduction in a breeding population of Hudsonian Godwits (Limosa haemastica).Publication Resource Selection of Human-associated Resources by Massachusetts Black Bears across Seasons and Reproductive Status(2024-09) Bonin, JessicaResource selection is a critical aspect of wildlife ecology, and understanding how animals interact with human-associated resources is of increasing importance as urbanization rapidly increases. This study investigates the resource selection patterns of Massachusetts black bears in relation to human-associated resources across various seasons and reproductive statuses. This study used black bear locations and availability of resources within bear home ranges to investigate selection using resource selection functions. Our findings reveal distinct seasonal resource utilization patterns among black bears. Spring and fall show increased use of areas characterized by human-development, with a notable preference for agricultural resources during the fall season. The proximity to human structures significantly influences resource selection, particularly during spring and fall. Bears consistently avoid locations with a high percentage of building structures throughout the year. This study did not detect a statistically significant difference in land cover selection between bears with newborn cubs and those without cubs, indicating that reproductive status may not substantially impact resource selection at this scale. For both reproductive statuses, the selection probability rises as the distance to human structures increases. Bears, both with and without cubs, are less likely to select locations as the percentage of building structures increases. These findings provide a foundation for future research endeavors, where the integration of bear-specific information into predictive models will enhance resource selection predictions. This knowledge contributes to effective wildlife management and conservation strategies, especially in regions characterized by significant human-bear interactions.Publication Whale Shark Tourism: Regulatory Compliance and Sustainable Ecotourism Practices in Quintana Roo Region, Mexico(2024-05) Ninh, HoaWhale shark (Rhincodon typus) (WS) tourism in Quintana Roo of the Yucatan Peninsula in Mexico has grown rapidly, generating nearly a million USD annually and providing a substantial number of jobs for the local economy. With increasing numbers of tourists, the Mexican government has developed WS Management Plans and associated codes of conduct to better manage the WS tourism industry in the region. The goals of this study are to evaluate current policies and practices associated with WS tourism in Mexico, and to provide tools for policymakers, conservationists, and tourism stakeholders to foster sustainable WS ecotourism We also present a case study evaluating regulatory compliance of WS ecotourism operations in Quintana Roo, Mexico. Using video footage collected by drones in August 2016 and August 2022, we found that the density of WS in the study area was lower in 2022 compared with 2016. Due to lower number of WS, boats and swimmers surrounded WS at greater concentrations in 2022. Between 2016 and 2022, the frequency boat violations related to approach distances increased threefold; yet frequency of swimmer violations related to approach distances remained nearly the same. Despite this, the frequency of WS touching violations by swimmers doubled. Although the presence of a enforcement patrol boat in 2022 probably led to a decrease in boat distance violations, swimmers appeared to be unaffected by their presence. There was a significant and positive relationship between the frequency of boat violations (per min) and the number of boats, swimmers, and WS. There was a significant positive relationship between the frequency of swimmer violations (per min) and the number of swimmers. In 2022, there was no differences in the frequency of boat distance violations when the patrol boat was present. To reduce the number of violations in the WS tourism industry, we suggest 1) limiting the number of boats and swimmers engaged with whale sharks each day; 2) increasing enforcement and monitoring (e.g., with drones) of boat and swimmer-WS interactions; and 3) increase tourist outreach efforts on the codes of conduct when swimming with WS.Publication New England Family Forest Owner Attitudes toward Passive Forest Management Options(2024-05) Clifford, Lina LaimuteFamily forest owners (FFOs) own the plurality of forests in the U.S. Though there is substantial research exploring FFO attitudes toward timber harvesting and programs incentivizing active management to maintain forest benefits, their attitudes toward passive forest management (PFM) options remain largely unknown. To address this gap, a mail survey instrument was deployed to a stratified random sample of New England FFOs to explore the scale and scope of FFO intent to adopt PFM on their land, their preferences for tools to adopt PFM, their perceived concerns and benefits of PFM, and the FFO and land characteristics associated with increased intent to adopt PFM. The results indicate there are mixed attitudes toward PFM with nearly 36% of respondents willing to adopt at least one of the hypothetical PFM scenarios on some or all of their land, with adoption on some land being more popular. Respondents interested in intentional PFM were not apathetic or unengaged landowners; they had strong goals for their land and engaged in activities on their land. The results of this study suggest there is great opportunity to engage FFOs in PFM to complement active forest management at a variety of intensities across the landscape to meet national and international land protection goals, increase landscape diversity and resiliency, and employ a greater diversity of forest management strategies to ensure the continuation of the multitude of forest benefits that we rely on.Publication Modeling the Coupled Effects of Climate Change and Land Use Patterns on the Distribution of Large Felids in the Chindwin River Basin of Myanmar(2024-05) Bol, Theint ThandarLarge felids including Bengal tigers (Panthera tigris tigris), Indochinese leopards (Panthera pardus delacouri), and Mainland clouded leopards Neofelis nebulosa), face imminent threats in Southeast Asia due to overexploitation, habitat destruction, and climate change impacts. The Chindwin River Basin (CRB), a critical biodiversity hotspot in Myanmar has witnessed a decline in the populations of these big cats, attributed to deforestation, habitat loss, and illegal wildlife trade. There is a crucial research gap regarding climate change and land use change impacts on the distribution of large felids in the CRB. The objective of this study is to assess the influences of climate and land use alterations on the distribution of large felids in the Chindwin River Basin (CRB) of Myanmar. Specifically, we aim to examine habitat suitability, identify key environmental variables influencing felid distribution, and project future changes in habitat suitability under different climate and land use scenarios. To achieve this objective, we used presence-only GIS points of three felid species which were collected through extensive camera trap surveys between 2013 and 2018 in critical areas of the CRB, including the Hukaung Valley Wildlife Sanctuary, Htamanthi Wildlife Sanctuary, Alaungdaw Kathapa National Park, and Hphonkanrazi Wildlife Sanctuary. For the environmental variables, we incorporated altitude, slope, aspect, land cover types, and bioclimatic data. Ten algorithms and an ensemble modeling approach were employed to develop Species Distribution Models (SDMs) for the three felid species. Remote sensing and Geographical Information Systems were utilized to evaluate land use changes, and future land use scenarios were projected using supervised classification and cellular automata models. Our study reveals that suitable habitats for large felids in the CRB are not uniformly distributed, with protected areas covering a significant portion (57%) but crucial areas outside protected areas being necessary for species survival. Distribution patterns are influenced by environmental variables, including elevation, slope, land cover types, and human-related activities. The intricate relationship with rivers highlights the necessity for targeted conservation measures along riparian zones. Climate variables, such as temperature and precipitation fluctuations, also significantly influence felid distribution. Future projections indicate a general trend of decreasing habitat suitability for large felids under various climate and land use scenarios, emphasizing the urgent need for proactive conservation actions to mitigate habitat loss and species decline in the region.Publication Torsional Shear Strength and Size Effect in Structural Composite Lumber(2012) Yang, ZhuoThe natural variation of strength properties within brittle materials leads to size effect, a well-known phenomenon whereby the mean strength of a material is observed to decrease as the stressed volume increases. An important implication of size effect is that size adjustment parameters must be incorporated into multi-axial constitutive and failure models used in numerical simulations to predict material response to loading. This experimental study seeks to verify and quantify the presence of depth effect under shear failure in the orthotropic principal material directions of parallel strand lumber (PSL) and laminated veneer lumber (LVL). Torsion tests have been performed on specimens of fixed length and differing cross section to get a pure shear failure, by using a Universal Test Machine. The experimental results indicate that there is no depth effect for LVL from torsional shear stresses. PSL testing was limited to one size, and depth effect was not evaluated. A finite element model was built to simulate the torsional test for the 44x140mm LVL specimen. Comparing the experimental test results and the simulation results, the model provided an accurate prediction of the torsional test for Structural Composite Lumber.Publication Investigation of Compliance with the Ansi Z133.1 - 2006 Safety Standard in the New England Tree Care Industry(2012) Julius, Alexandra KArborists are exposed to many occupational hazards and experience more than three times the overall fatality rate of all U.S. workers. Investigations into fatal incidents lead to a better understanding of industry dangers. However, this knowledge does not extend to how tree workers operate when an injury or fatality does not occur. Current research regarding fatal and nonfatal injuries does not include the accreditation status of the company at which the worker was employed, nor whether certified arborists were on staff. Given the highly skilled nature of the work involved, certification and accreditation might ensure a minimum level of demonstrated safety practices. This study aimed to 1. Determine whether certification and accreditation in the tree care industry are associated with safer workplace behavior, and 2. Identify safety practices that tree workers commonly violate. Tree care companies in southern New England were divided into three categories: accredited, non-accredited with certified arborists on staff, and non-accredited with no certified arborists on staff. A stratified random sample of 63 companies was evaluated in the field by direct observation, assessing workers’ adherence to the industry’s safety standard, the American National Standards for Arboricultural Operations (ANSI Z133.1-2006). Analysis indicated that, overall, accredited companies and those with certified arborists on staff complied with the Z133.1 Standard more than those without. Although these companies were more compliant, few significant differences emerged, and low overall compliance was found for personal protective equipment and chainsaw and chipper safety. There were low levels of compliance across all types of companies with the basic aspects of safety, including feeding the chipper from the curbside, not drop-starting a chainsaw, and using head, eye, and hearing protection. Implications of findings include possible considerations for improvements on accreditation and certification processes. Further findings address aspects of the Z133.1 Safety Standard that are currently unclear.Publication Factors Influencing Increased Sustainable Harvesting and Primary Processing of Massachusetts Native Woods(2012-05) Zhao, YuxiForest-related practitioner’s harvest/business expansion decisions are important in that these decisions, although individually made, have a cumulative influence on the overall prosperity of the forest products industry and forest coverage in Massachusetts. This paper explored the decision making process of five stakeholder groups in Massachusetts’ forest products production and distribution chain - landowners, foresters, loggers, sawmills, and wholesalers - aiming to find out what factors or specific possible reasons influence each stakeholder’s harvest/business expansion decisions. In recent years, Massachusetts has had a shrinking forest products industry despite a healthy forest with growing tree volumes. This has led to a dependence on imports for its local forest products consumption. To solve this problem, Damery, Yadav, & Zhao (2008) surveyed landowners, foresters, loggers, sawmills and wholesalers to identify barriers to expansion of the local forest products industry. This paper takes advantage of the data gathered and conducts further analysis to answer the question: despite the barriers, why do some practitioners still choose to make harvest/business expansion decisions while others do not? For landowners, foresters, and loggers who have sufficient useful responses, quantitative analysis was conducted through statistical hypothesis testing and econometric modeling to identify causal factors that may lead to the differences. Factors of significance were: 1) years of forestland ownership, 2) Chapter 61 enrollment, and 3) willingness to harvest with neighbors for landowners; 1) practicing years, 2) previous assisted harvest volumes, 3) workmen’s compensation concern, and 4) small-diameter log markets emphasis for foresters; and 1) nature of logging operation (hobby/part-time/full-time), and 2) competition concern for loggers. Due to the small sample size for sawmills and wholesalers, qualitative analysis was conducted through anecdotal analysis to reveal specific possible reasons, rather than generalizable factors, that may explain different choices. Among all nine factors identified, five of them concerning stakeholder’s attitudes and choices have the potential to be influenced by policy. Programs that can: increase landowner enrollment in Chapter 61, promote cooperation with neighboring landowners, mitigate forester concern with workmen’s compensation, improve markets for small-diameter logs, or improve the competitive landscape for loggers, have the potential to increase production of Massachusetts native woods.Publication Population Size, Habitat Use and Diet of Kittlitz's Murrelets in Prince William Sound, Alaska(2012) Allyn, Andrew JDuring the summer of 2008 and 2009, we studied the ecology of the Kittlitz’s Murrelet (Brachyramphus brevirostris), a small diving seabird and candidate for the U.S. Endangered Species List, in Prince William Sound (PWS), Alaska. At-sea survey data suggests that the population significantly increased from 2001 to 2009, however there is limited evidence of reproductive success. Habitat use models showed individuals were observed in shallower waters, closer to glaciers, the shoreline, and further from moraines than the available habitat during the daytime. Finer extent sampling from 2008 suggests temperature-depth profiles also influence Kittlitz’s Murrelet daytime habitat use. The associations between Kittlitz’s Murrelets and water column characteristics are likely an effect of prey availability. Stable isotope work in 2009 suggests birds were generalist foragers prior to the breeding season, becoming more specialized following the breeding season. This specialization may have been a response to strict foraging constraints during the flightless fall molt. Time budgets of radio-tagged individuals suggest birds may have been responding to ephemeral prey concentrations, and working near their maximum energetic limits. Remote monitoring of radio-tagged individuals showed birds left the glacial fjord system during the nighttime, possibly spending these hours near gillnet fishing areas, suggesting a new possible area of concern in evaluating potential threats to Kittlitz’s Murrelet populations.Publication Building Integrated Aquaculture(2011-09) Woodin, Erik AExploratory research into a fresh concept, building integrated aquaculture, has found new information on the topic. Motives indicating building integrated aquaculture is important for sustainable development were identified. A review of the literature found relatively little in the way of experiments, aquaculture operations, and case studies which documented or demonstrated a deep understanding of the interactions between building and aquaculture systems. A simple experiment was conducted observing thermal energy and moisture interactions in simulated aquaculture facilities, some with tank covers and insulation. Two different retrofit programs were developed in a case study of building integrated aquaculture for an existing structure on the campus of the University of Massachusetts.Publication Evaluating the Influence of Disturbance and Climate on Red Spruce (Picea rubens Sarg.) Community Dynamics at its Southern Range Margin(2011) Ribbons, Relena RPicea rubens(red spruce) populations experienced a synchronous rangewide decline in growth and vigor starting in the 1960’s, which was likely caused by climate change or environmental disturbances (e.g., acid deposition); However, it is yet unknown if populations continue to decline or have recovered. In the context of global warming, red spruce is a species of concern because it is at its southern continuous range margin in Massachusetts. This study uses tree-ring data coupled with population data from permanent plots to quantify the status of red spruce in Massachusetts. Tree cores were extracted from red spruce and used to examine radial growth rates, determine a growth-climate relationship, and document disturbance events. Red spruce at these plots ranged from 90 to 184 years old, and comprised 15 to 29 m2/ha-1 basal area. Over the past 50 years, red spruce has decreased in density, basal area, and relative importance while red maple, yellow birch, and American beech have increased. Red spruce saplings persisted in some plots, but the sapling layer was comprised mostly of American beech or red maple. However, red spruce seedlings were common at red spruce dominant plots indicating that if favorable conditions occur, it could return to its more dominant position in the canopy. Dendroclimatological analyses show that red spruce is sensitive to both temperature and precipitation. Most sites are correlated with temperature, while only twoforests were correlated to precipitation. The general temperature response of the red spruce studied was positively correlated with winter temperatures while the general precipitation response was negatively correlated with precipitation. Temporal analysis of the climate-growth response indicates that red spruce here have not had a temporally-stable, climate-growth relationship. Prior to 1960, radial growth was positively correlated with temperatures from November of the previous growing season to January of the current year. After 1960, all sites showed a shift in growth responses consistent with increased summer temperature stress; narrowed tree rings were formed during warm temperatures in July and August. Precipitation remained relatively constant over the past century, while temperatures have increased up to 2˚C across the study area. Of the two precipitation-sensitive forests, one forest shifted from being positively correlated with current January precipitation to negatively correlated with previous October precipitation while the second forest showed a strong positive relationship with August precipitation. Because the radial growth of red spruce here are mostly constrained by temperatures, there has been negative growth response to regional warming and precipitation has been stable, I suggest the change in climate response is potentially due to warming and a physiological threshold response to increasing temperatures. Interestingly, disturbance frequency and intensity have increased over the same time period, which could be either a trigger or a response to the shift in the growth-climate relationship.Publication Patterns in Trash: Factors that Drive Municipal Solid Waste Recycling(2014) Starr, JaredMunicipal recycling is driven by a variety of factors. Yet how these factors change over time is not well understood. I analyze a suite of contextual and program variable in multiple time periods, spanning 16 years, in the Commonwealth of Massachusetts. Based on the models run, I reach the surprising conclusion that most program variables have an insignificant effect on recycling rates. These findings can inform municipal officials and waste managers as they seek new ways to increase municipal recycling participation.Publication An Assessment of Environmental Dna as a Tool to Detect Fish Species in Headwater Streams(2014-02) Jane, Stephen FRecent years have seen an explosion of interest in the use of freely available DNA present in aquatic systems, otherwise known as environmental DNA (eDNA), as a tool for monitoring aquatic organisms. However, much remains unknown about the behavior of eDNA over a range of environmental conditions. This is particularly true in high gradient headwater streams, which have received less attention than other types of water bodies. In the summer of 2011, a headwater stream system with well established species distributions was sampled using eDNA techniques. Though species were detected where known to be present, detections also occurred where traditional techniques failed to detect species. This suggests that a cautious approach to positive eDNA detections is advisable. In 2012 a second study was conducted to better understand the dynamics of eDNA concentration in lotic systems. Caged brook trout (Salvelinus fontinalis) were introduced into two otherwise fishless headwater streams, and eDNA samples were collected at evenly spaced intervals downstream of the cage. This was repeated 19 times from mid-summer through autumn, over flows ranging from approximately 1 to 96 l/sec. Quantitative PCR was used to relate DNA copy number to distance from source for each of these 19 sampling events. In all cases, DNA was detectable at 239.5 m from the cage. Increasing flows generally decreased eDNA copy number near the cage but had relatively little effect at downstream sites. Additionally, the presence of leaf biomass during the fall period had the potential to completely erase otherwise high DNA levels.Publication A Comparison of American, Canadian, and European Home Energy Performance in Heating Dominated – Moist Climates Based on Building Codes(2014) Berkland, Stephanie MThis research compares the energy performance of a code-built residential building within the moist climate zone classification in Canada, Europe, and the Northeastern United States. The primary objectives are to reveal how specific differences in code requirements in similar climates influence a building’s energy profile, offer a means to quantify and evaluate the extent of energy savings as a result of each requirement, and provide a comparison of each location’s building culture and how this affects the standards in place. Using the building energy simulation tool, DesignBuilder EnergyPlus Simulation, a model single-family home was created and input energy code requirements for each location. An evaluation of each location’s building culture is examined through such factors as the training of building professionals, commonly used materials and products, energy reduction goals, and cultural attitudes. The results of this study point to the need for more advanced building practices, stricter code mandates, and higher performing products based on energy savings achieved from buildings built to different standards in equivalent climate zones. This has the potential to drive the development and use of better performing building materials and assemblies in the future.Publication The Effect of Leaves and Steel Support Cables on The Dynamic Properties of Northern Red Oak (Quercus rubra) with Co-Dominant Trunks(2013) Reiland, MarkNatural frequency and damping ratio were measured for ten forest grown northern red oak trees with co-dominant trunks. Steels support cables were installed in the canopies of five of the sample trees prior to measurement. Free vibration testing was performed during periods when leaves were and were not present. An accelerometer mounted at the base of the co-dominant union measured the acceleration time history during the free vibration testing. Natural frequency was determined from the acceleration time history using power spectral density analysis. Damping ratios were calculated from the power spectral density plots using the half power bandwidth method. Trees with steel support cables had higher natural frequencies than trees without steel support cables. Sample trees had higher natural frequencies in the leaf off condition than the leaf on condition. The increase in natural frequency associated with the steel support cable was less pronounced in the leaf on condition. There was no difference between the damping ratios of cabled and non-cabled trees. Trees in the leaf on condition had significantly higher damping ratios than trees in the leaf off condition.Publication Aquatic Barrier Prioritization in New England Under Climate Change Scenarios Using Fish Habitat Quantity, Thermal Habitat Quality, Aquatic Organism Passage, and Infrastructure Sustainability(2013) Jospe, Alexandra CImproperly designed road-stream crossings can fragment stream networks by restricting or preventing aquatic organism passage. These crossings may also be more vulnerable to high flow events, putting critical human infrastructure at risk. Climate change, which will require access to suitable habitat for species persistence, and is also predicted to increase the frequency and magnitude of extreme floods, underscores the importance of maintaining stream connectivity and resilient infrastructure. Given the large number of road-stream crossings and the expense of replacement, it is increasingly important to prioritize removals and account for the multiple benefits of these management actions. I developed an aquatic barrier prioritization scheme that combines potential habitat gain, stream thermal resilience, aquatic organism passage, and culvert risk of failure. To assess relative thermal resilience, I deployed paired air-water thermographs in several New England watersheds and analyzed relative thermal sensitivity (relationship of water to air temperature) and exposure (duration, frequency, and magnitude of warm stream temperature episodes) among streams. These were combined into a single metric of thermal resilience corresponding with the distance of that stream’s sensitivity and exposure from the watershed median. To test the relationship between risk of failure, culvert dimensions, and stream connectivity, I developed a logistic regression to predict risk of failure using data from two watersheds that experienced extreme flooding from Hurricane Irene (2011). Finally, I applied the resultant prioritization scheme to 66 road-stream crossings in the Westfield River watershed (MA). Thermal habitat quality varied considerably within and among watersheds. Stream sensitivity was generally lower than the widely accepted 0.8 ̊C increase in stream temperature for every 1 ̊C increase in air temperature (Westfield median sensitivity = 0.44), with substantial differences among streams. Exposure also varied widely among streams, indicating that some headwater streams in New England are more thermally resilient than previously thought. Risk of infrastructure failure was predicted with a logistic regression using culvert constriction ratio and predicted aquatic organism passage as predictors (Likelihood ratio test, X2=59.1, df=3, p- value=9.2e-13), indicating that underdesigned culverts were more likely to be barriers to passage and more likely to fail in extreme flow events. To prioritize culverts, this study ultimately used a piecewise approach that identified culverts opening the longest reaches of thermally resilient habitat, and then ranked those culverts by infrastructure replacement need. In the Westfield River, the prioritization clearly identified crossing replacements most likely to yield multiple benefits. The scheme I developed can accommodate changes in the relative weights of the different criteria, which will reflect differences in management and conservation concerns in the confidence of inputs. In conclusion, increasing connectivity by removing barriers may be one of the most effective ways to mitigate the effects of climate change on aquatic systems, but it is important to remove the right barriers.Publication Implementation of Aquaponics in Education: An Assessment of Challenges, Solutions and Success(2013-09) Hart, Emily RoseAquaponics is the combination of aquaculture and hydroponic technology to grow both fish and plants together in a closed-loop system. While aquaponics can play a role in increasing food security, it may also be a potential educational tool because of its interdisciplinary nature and required technological skill set. With aquaponics, students could conduct hands-on activities involving chemistry, physics and biology to solidify their understanding of a range of theories. Beyond standard science, technology, engineering and mathematics (STEM) principles, aquaponics may be related to projects on sustainability, environmental science, agriculture, the food system, health, economics, business and marketing. The interdisciplinary nature of aquaponics may make it an appealing tool for education, yet that same aspect may also make an aquaponics system challenging to implement and manage. Given this paradox, this exploratory research assesses challenges, solutions and success of aquaponics in education with a specific focus on implementation. Qualitative data were collected through phone interviews with educators (n=10) who currently, or had in the past, used an aquaponics system in an educational setting in North America. The most frequently described uses for aquaponics were flexible, hands-on teaching and learning of STEM and food-related concepts. Participants reported two broad challenges to implementing aquaponics: technical difficulties as a result of the nature of aquaponics and restrictions as a result of their school settings. Solutions given by participants were physical aquaponics system modifications and the development of intangible characteristics, especially community connections and support, passion for aquaponics and expertise. In this study, success in aquaponics in education emerged as a cyclical pattern: participants valued the overall learning experiences of aquaponics and the continued application of these learning experiences. Ultimately, these exploratory findings will help educators manage their expectations for aquaponics while establishing objectives for their particular educational settings.