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The Effects of Several Paper Characteristics and Application Methods on the Sublimation Rate of CyclododecanePiotrowski, KELLI 28 September 2013 (has links)
Cyclododecane (CDD) is a waxy, solid cyclic hydrocarbon (C12H24) that sublimes at room temperature and possesses strong hydrophobicity. In paper conservation CDD is used principally as a temporary fixative of water-soluble media during aqueous treatments. Hydrophobicity, ease of reversibility, low toxicity, and absence of residues are reasons often cited for its use over alternative materials although the latter two claims continue to be debated in the literature. The sublimation rate has important implications for treatment planning as well as health and safety considerations given the dearth of reliable information on its toxicity and exposure limits. This study examined how the rate of sublimation is affected by fiber type, sizing, and surface finish as well as delivery in the molten phase and as a saturated solution in low boiling petroleum ether. The effect of warming the paper prior to application was also evaluated. Sublimation was monitored using gravimetric analysis after which samples were tested for residues with gas chromatography-flame ionization detection (GC-FID) to confirm complete sublimation. Water absorbency tests were conducted to determine whether this property is fully reestablished. Results suggested that the sublimation rate of CDD is affected minimally by all of the paper characteristics and application methods examined in this study. The main factors influencing the rate appear to be the thickness and mass of the CDD over a given surface area as well as temperature and ventilation. The GC-FID results showed that most of the CDD sublimed within several days of its disappearance from the paper surface regardless of the application method. Minimal changes occurred in the water absorbency of the samples following complete sublimation. / Thesis (Master, Art Conservation) -- Queen's University, 2013-09-27 09:00:28.77
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QUANTIFYING THE HYDROLOGIC IMPACT OF MOUNTAIN PINE BEETLE DISTURBANCE IN A WESTERN MONTANA ECOSYSTEMReilly, James A. 20 June 2014 (has links)
Mountain pine beetle (Dendroctonus ponderosae, MPB) is a forest pest endemic to the Rocky Mountain West. Since the late 1990s, millions of hectares of lodgepole pine forest have experienced extensive tree mortality due to MPB disturbance and this may have significant implications for forested mountain water supplies. MPB disturbance may affect the amount of moisture that enters and leaves the forest hydrologic system, through changes in snowpack accumulation, snowmelt timing, transpiration and subsequently soil water content. The cumulative effect of these changes is that soil moisture is expected to be higher in disturbed forests as the hydrologic system responds to increased inputs and the cessation of canopy transpiration that accompanies tree mortality. This research examined how MPB-disturbance affects the forest water balance in three plots in western Montana using direct observation and modeling methods. Peak SWE, snowmelt and post-snowmelt water balance parameters were measured in three study plots: a non-disturbed lodgepole pine plot, a plot consisting of lodgepole pine trees in the advanced stage of MPB disturbance, and a nearby clear cut. No significant differences in peak SWE and snowmelt timing were measured between the MPB-disturbed and non-disturbed due to the higher stand density and basal area. However, post-snowmelt measurements of soil moisture, rainfall, understory evapotranspiration and canopy transpiration indicated higher net precipitation and understory evapotranspiration in the MPB-disturbed plot. Additionally, soil moisture was higher in the MPB-disturbed plot, which was likely explained by the absence of canopy transpiration fluxes. Additionally, beyond the factors quantified in this initial study, it is likely that topography and variability in stand characteristics played an important role for observed differences in soil water content. This study provides first steps towards assessing the implications of MPB for changes in mountain water supplies in forested catchments. Future work should seek to use additional study plots with more similar stand characteristics and local topography.
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Use of Climatic Water Balance Metrics as Site Productivity PredictorsPerry, Matthew Dilsworth 20 June 2014 (has links)
Estimates of long-term forest site productivity are required to inform multiple forest management objectives including growth and yield assessments, silvicultural planning, and biomass/carbon projections. Estimates traditionally have been quantified in the form of site index by measuring the average height-age relationships of dominant and codominant trees or using regional site index equations. Site index implementation requires that trees are free from suppression and that height growth results from the integration of the biological determinants of growth. While useful in even-aged stands, early age height growth suppression is common in uneven-aged forest structures making existing site indices difficult to assess. Additionally, the individual biological determinants of growth are not identified and do not provide a basis for site index to be mapped across the landscape or predicted under alternative climate scenarios. This research aims to characterize the major physiographic and climatic determinants of growth.
We obtained site index estimates for 203 ponderosa pine, 343 Douglas-fir, 232 lodgepole pine and 99 western larch trees throughout the state of Montana using regional equations (Milner 1992). Terrain descriptors (slope, aspect and elevation), climate normals (min/max temperatures, vapor pressure deficit), and climatic water balance (actual evapotranspiration and deficit) were derived for each site index tree at various resolutions (list range of resolutions ). Regression analysis was performed using a hierarchy of terrain, climate and mixed models. Slope, aspect, and elevation were able to explain approximately half the variation in site index for ponderosa pine, lodgepole pine and western larch. Geographically localizing the model increased the variance explained by the terrain models for all species except western larch. A simple climatic water balance interaction model (AET x DEF) was unable to explain much of the variation in site index. However, when climatic water balance was added to the terrain model the variance explained increased for all species. A biophysical model utilizing only water balance and climate variables explained more of the variation in site index than terrain based models for all species. Implications of spatial accuracy of the climatic data products and fine scale variation in tree data are discussed and recommendations for future research are provided.
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Ecology, management and conservation of Pinus roxburghii forests of the Kumaun Himalaya, IndiaBurfal, B. S. January 1988 (has links)
No description available.
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Forest genetic conservation in Brazil : a review of priority taxa for the 'Cerrado'Leite, Edson Junqueira January 1994 (has links)
No description available.
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An investigation into integrating knowledge for conservationEvely, Anna Clair January 2010 (has links)
This thesis analyses the integration of knowledge (disciplinary, expert and lay) in order to contribute to the understanding of how knowledge can be integrated for conservation. Specifically, the thesis asks: a) how the knowledge of social and natural sciences can be integrated to better manage social-ecological systems; b) what the barriers are to integrating different types of knowledge; c) what the outcomes are of integrating different forms of knowledge; d) what type of participation can best sustain action; and e) how participation can improve adaptive capacity. In Chapter 3 the underlying philosophies of the social and natural sciences are mapped out and evaluated, demonstrating how taking one philosophical stance over another influences project methodology and outcome. The mapping process may also benefit knowledge integration by enabling researchers to make their underlying assumptions explicit. In Chapter 4 current cross-disciplinary research in conservation is analysed: results suggests more integrative research (interdisciplinary or trans-disciplinary) has a higher impact on practitioners whereas less integrative research has a higher impact on colleagues. Using conservation case studies from England, Scotland and Wales, Chapters 5 and 6 investigate some claims made for participation in conservation. Chapter 5 analyses the satisfaction of participants with implications for participant recruitment and retention. Chapter 6 evaluates how participation and how particular participatory approaches may influence participant learning. Results indicate a strong link between the integration of participants and types of learning that are considered to build adaptive capacity. Findings indicate that the approach taken to integrating knowledge can directly affect who benefits from the research, methodological flexibility participant satisfaction and learning.
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Investigating the effects of noise pollution from energy development on the bat community in the Piceance BasinWarner, Katherine Anne 01 September 2016 (has links)
<p> Throughout the United States, and globally, there has been recent interest in large-scale monitoring of bats, driven largely by the many threats that bats currently face such as climate change, white nose syndrome, habitat loss, and wind energy development. Additionally, many human activities generate sensory disturbances including anthropogenic light and noise pollution that have been shown to affect habitat use and foraging efficiency in bats and other wildlife. My research took place in the Piceance Basin of northwestern Colorado, where there has been considerable development of natural gas resources in recent years. During the drilling phase for natural gas, drill rigs run continuously for weeks to months at each well development site. In addition to the physical disturbance and increased human presence at the well pad, drill rigs are brightly lit, and also emit high amplitude anthropogenic noise. The light and noise from active drill rigs can travel many miles from the source, far beyond areas where wildlife habitat has been physically disturbed. The goal of my research was to isolate noise from the other associated forms of disturbance, and investigate what, if any, effects drilling noise is having on the bat community. </p><p> My dissertation is comprised of three stand-alone chapters, as follows. In Chapter 1, I test two different strategies for deploying bat detectors to determine which strategy yields higher detection and species identification rates. In Chapters 2 and 3, I present the results of noise playback experiments. Chapter 2 compares bat activity levels at control sites, and at treatment sites where noise was added experimentally. In Chapter 3, I monitor bat activity patterns both during and after a noise playback experiment to determine how rapidly activity levels recover post-exposure. A brief summary of each chapter follows. </p><p> In Chapter 1, I focus on the methods for recording bat echolocation calls, and identifying free-flying bats in the field. Unlike capture techniques, current acoustical methods for bat monitoring do not provide information about unique individuals, age, sex, or reproductive status. What acoustical monitoring can provide is information about bat activity levels, habitat use, and species identification in some cases, without interfering with bat movement, foraging, or other activities. The commercially available technology for recording bat echolocation calls has rapidly advanced, and there are many ultrasound detector–recorder systems (hereafter, ‘bat detectors’) available with a wide range of recoding options. Due to rapid attenuation of ultrasound signals, one of the challenges to acoustical monitoring is the relatively limited recording range of bat detectors. To increase this range, I took advantage of a bat detector that had the ability to record on two channels (in stereo). By attaching microphone extension cables, I was able to increase the distance between the left and right channel microphones, thereby increasing the acoustical sampling space. When this data collection effort took place, the SM2BAT+ detector from Wildlife Acoustics, Inc. was the only commercially available bat detector that had the two-channel recording capability. I deployed two identical bat detectors at each study site, and compared the recordings made using the stereo option to recordings made from a single channel. </p><p> In general, the stereo setup outperformed the single-channel systems. With the stereo microphones separated by approximately 10 m, the bat detectors that recorded in stereo produced 2.7 times more recordings overall. The increased number of recordings resulted in a higher number of calls that could be identified to species. The benefit of the stereo setup was not equal for all species. With the stereo microphones only about 10 m apart, there was some overlap between the calls that were identified on the left and right channels. The highest rate of overlap (19.5%) was in big brown bats (<i>Eptesicus fuscus </i>). Rates of overlap for species in the Myotis genus were all less than 5%, and none of the recordings of pallid bats (<i>Antrozous pallidus </i>) were identified on both channels for the same bat-pass-event. The stereo option is a promising way to increase the number of bat recordings, which may be a particularly useful when surveying for rare species. </p><p> In Chapter 2, I used a noise playback experiment to isolate noise from other forms of anthropogenic disturbance, and monitored the bat activity level response. I recorded the sounds of an active drill rig, and played these recordings at treatment sites. I measured sound pressure levels at the drill site, and estimated the sound pressure levels at the noise playback sites. Using outdoor speakers, I was unable to project the drill rig noise at the same amplitude of an actual rig, but I was able to significantly elevate the sound levels at treatment sites. The noise levels at treatment sites roughly corresponded to noise levels that can be experienced approximately 100 m from a drill rig. This distance from a drill rig is typically beyond the well pad, in habitat that is not physically disturbed. There is widespread recognition that noise, light, and other sensory disturbances can affect the behavior and physiology of wildlife. The goal of the experiment was to determine if noise alone impacted the activity levels of bats, after being separated from the other forms of disturbance at a drilling site. I projected noise at treatment sites that were not already developed, and paired these treatment sites with control sites with no added noise. I conducted this experiment in 2013 and 2014, and present the results from 20 sites each year (10 control-treatment pairs annually). </p><p> Both years, there was an overall decrease in bat activity at treatment sites, when compared to control sites. In 2013, 8 of the 10 treatment sites had lower estimated bat activity levels. In 2014, all 10 treatment sites had lower estimated activity levels, although for some control-treatment pairs there was overlap in the credible intervals. Multiple species showed signs of reduced activity at treatment sites. For both years, <i>M. ciliolabrum </i> and <i>L. cinarius</i> had reduced activity levels at treatment sites. The response of other species was more idiosyncratic, with reduced activity in one field season, and inconclusive or no response during the other year. The species that did respond to the noise treatment have very different life histories, making it difficult to generalize about how any given species may respond to noise. </p><p> Chapter 3 focuses on bat activity level trends over time during a two period cross-over experiment. The classic two-period crossover experiment consists of two treatments (i.e., treatments ‘A’ and ‘B’), where each site is exposed to both treatments, and the order of the treatments is randomly assigned. For this study, ‘A’ refers to no added noise, and ‘B’ refers to a noise treatment consisting of the projected recording of drilling noise. A total of 12 sites were randomly assigned to the A:B sequence, and 13 sites were assigned to the B:A sequence. I acoustically monitored bat activity throughout the experiment, with particular interest in understanding the activity level dynamics post-exposure to the noise treatment. Most studies that investigate the impacts of noise on wildlife have focused on the response to noise during a noise treatment period, or noise event. Only a handful of previous studies have addressed the post-exposure period after noise ends. In these studies, noise treatments or events were relatively short in duration (a few minutes), and the corresponding recovery period was monitored over a similarly brief timeframe. My study differs in both the duration of the noise treatment (continuous noise over six days/nights), and in the duration of the post-exposure monitoring period (also six days/nights). I focused on the response of four bat species, <i>Myotis ciliolabrum, Myotis evotis, Lasiurus cinareus,</i> and <i>Taderida brasiliensis.</i> </p><p> Of the four focal species, <i>M. evotis</i> showed no substantial response to the noise treatment. The responses of <i>M. ciliolabrum</i> and <i>T. brasiliensis</i> were somewhat challenging to interpret. The overall activity levels of these species were lower during the treatment period in the A:B sequence, but they also had declining activity levels throughout the pre-exposure period. The activity patterns of <i>L. cinareus</i> provided the most convincing evidence of noise avoidance. Furthermore, <i> L. cinareus</i> activity levels did not show signs of recovery after the noise treatment ended in the B:A sequence. This suggests that after the six-day post-exposure period, there were still lingering effects of noise on <i>L. cinareus</i> activity levels. This study provides evidence that the effects of noise can linger for multiple days post-exposure. Future wildlife studies that assess periods of post-exposure could contribute meaningfully to this area of research, and aid in the development of conservation and mitigation efforts.</p>
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The conservation of historic cities and architectural heritage in Brazil, with particular reference to the state of Minas Gerais and the city of MarianaCaldeira, Altino Barbosa January 1997 (has links)
This piece of work analyses the existing condition of the Brazilian. architectural heritage, focusing especially on the historic cities. In order to make it possible, the study first of all analyses the Brazilian historical background with the purpose of establishing a relationship between the circumstances and conditions in which these cities were created. Initially, the scenery of the landscape, the geographical aspects of nature, the climate and the people who converged on this New World in South America, thus initiating the Brazilian diversity of culture and behaviour, are considered. Historical, political, social, and financial factors which were involved in the construction of these cities are also shown in order to facilitate the understanding of their character and meaning. The aim of this study is to analyse aspects of the conservation of listed buildings in these special areas known as historic cities. In order to evaluate the extent of the problem, and because the Brazilian official institution which is responsible for the care of the heritage is supported by the government, specific situations occurring in different regions will be shown. The legislation related to the protection of the listed artefacts in which are included listed buildings and also urban areas is analysed in its application and results. This study takes into account the most important concentration of historic cities in Brazil, which were constructed in the eighteenth century, in the state of Minas Gerais, and then, describes the in-depth research conducted in one of these special cities - Mariana - in order to provide data and arguments for the evaluation of the protection of the historic cities in Brazil. Looking initially at the whole of the Brazilian architectural heritage values, and then focusing on a special area in order to study and evaluate rules and schemes concerning the protection and conservation of the historic cities, this research aims to find a methodology for the restoration and conservation of those cities as a whole.
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Estuarine habitat use by the California sea otter (Enhydra lutris nereis)Lindsey, Jacqueline Kimberly 11 February 2017 (has links)
<p> As the southern sea otter (<i>Enhydra lutris nereis</i>) range expands into northern and southern California, it will encounter estuaries that have been historically occupied by sea otters. Understanding how otters use re-colonized estuarine environments will inform how estuaries might be managed to encourage future sea otter range expansion. This project addressed the question: how do southern sea otters use space in the unique estuarine habitats of Elkhorn Slough? I compared the locations and behaviors of 25 individual sea otters of different status (male, female, and female with pup) among eelgrass, saltmud, saltmarsh, tidal creek, and main channel habitats in Elkhorn Slough. From these data I created a synoptic model to predict space use for resident otters of Elkhorn Slough based on sex, behavior, home range, and habitat distribution. Ninety percent home ranges calculated from the model indicated that females used larger home ranges than males in the slough, but both sexes had smaller home range areas than otters using the rocky outer-coast habitats of the Monterey Peninsula. In Elkhorn Slough, important habitats associated with resting included tidal creeks (for females only) and eelgrass, whereas the main channel was important for foraging behaviors of both sexes. Although using land habitats, sea otters were most likely to be found within 50 m of water. Protection of similar resting and foraging habitats in prey-rich estuaries colonized in the future will promote southern sea otters recovery by allowing them to re-colonize historically important estuarine habitats. </p>
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Speciation and Ecological Niche Divergence of a Boreal Forest Bird Species ComplexFitzGerald, Alyssa 07 June 2017 (has links)
<p> Evolutionary biologists are supremely interested in the events that cause populations to diverge and speciate, and the mechanisms that maintain divergence over time. Here, I investigate the evolutionary history of a boreal bird species complex. Boreal bird species are co-distributed, diverged during the Pleistocene, and generally have patterns of genetic divergence that are consistent with a single “boreal” clade in northern and eastern North America. The Gray-cheeked Thrush species complex, however, shows a possible species break in eastern North America between the Bicknell’s Thrush (<i> Catharus bicknelli</i>) and Gray-cheeked Thrush (<i>Catharus minimus </i>). Using population genetic and genomic analyses of the largest sampling to-date of either species, I find that the eastern break indeed coincides with a species-level divergence, although low levels of admixture in a few individuals and one probable hybrid hint at the possibility of occasional hybridization. Species distribution models (SDMs) of the Last Glacial Maximum revealed that divergence may have been maintained by residence in different late-Pleistocene refugia. However, because speciation occurred mid-Pleistocene, I examined the geographical context of divergence of the Bicknell’s Thrush and Gray-cheeked Thrush using multivariate analyses and ecological niche modeling techniques of local-scale habitat data and broad-scale climate and tree species distributions. Local-scale habitat analyses reveal that the thrushes breed at sites with unique tree species composition, physiognomy (forest structure), and ground cover characteristics; furthermore broad-scale analyses reveal that niche divergence, rather than conservatism, was the predominant pattern for these species, suggesting that ecological divergence has played a role in their speciation. This dissertation supports the hypothesis that the Bicknell’s Thrush and Gray-cheeked Thrush are distinctive species that breed in divergent local- and broad-scale niches and emphasizes that this species-level divergence seems unique among boreal bird species.</p>
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