Most sociological analyses of community attachment have focused on the strength of attachment, with little concern for the qualities or attributes of a place to which people become attached. In cases where dimensions of attachment are the focus of analysis, the literature is rather narrowly focused on social dimensions, re ferring most often to connections with family, friends, and other social networks and largely ignoring the realm of natural environment factors. Two primary premises motivated this study. Fi rst, sociological understandi ngs of community attachment wou ld benefit from an expanded analytic framework that incorporates more complex arrays of both social and natural environment dimensions. Second, it is important to understand what variations in attachment may mean for the broader well-being of rural communities. Initial analyses of the data demonstrated four key results. First, factor analysis of fi fleen indicators of attachment produced two distinct dimensions of community attachment, social and natural environment. Second, the nature of the response patterns indicates that strength of natural environment attachment is widely shared amongst a variety of res idents, regardless of length of residence, historical roots to the area, or life cycle. Third, participation in collective action and perceptions of open communication (measures of well-being) within a respondent's community explained only a small portion of the variance in both social and natural environment attachment. Fourth, Structural Equation Modeling demonstrated that there is a causal relationship between attachment and community well-being, though that relationship appeared to be non-recursive. In contrast to much of the previous empirical work on community attachment, this research provides strong evidence of the natural environment dimension and provides justification for further research. This research provides one model to be considered and expanded upon in future research efforts in this area, and supports the need for further attention to the use of multiple dimensions of attachment and their associations with community well-being.

Parker Mountain, is located in south central Utah, it consists of 153 780 ha of high elevation rangelands dominated by black sagebrush (Artemisia nova A. Nelson), and mountain big sagebrush (Artemisia tridentata Nutt. subsp. vaseyana [Rybd.] Beetle) communities. Sagebrush obligate species including greater sage-grouse (Centrocercus urophasianus) depend on these vegetation communities throughout the year. Parker Mountain is owned and managed by Utah School and Institutional Trust Lands Administration, Bureau of Land Management, and the United States Forest Service. Land management on Parker Mountain include wildlife conservation and providing sustainable ecosystem services such as livestock grazing. My research described the species composition of the black sagebrush communities, evaluated the long-term vegetation responses to two mechanical (Dixie harrow/Lawson aerator) and one chemical treatment (tebuthiuron), and herbaceous biomass responses to tebuthiuron treatments in mountain big sagebrush communities on Parker Mountain. My results indicated when black sagebrush canopy cover was <20%, average grass canopy cover was highest (13%). When black sagebrush canopy cover exceeded 40%, grass canopy cover was lowest (8%). Forb canopy cover was relatively consistent (5%) across black sagebrush communities with >20% canopy cover. Communities with <20% black sagebrush canopy cover had the lowest forb canopy cover. Tebuthiuron reduced mountain big sagebrush percent canopy cover (>9 years), increased grass canopy cover, and increased forb canopy cover more than the two mechanical brush control methods. Tebuthiuron treatments shifted sites from xeric to more mesic plant communities, which resulted in increased percent forb cover required by greater sage-grouse during late-brooding. Herbaceous biomass increased under tebuthiuron treatments in mountain big sagebrush pastures. Tebuthiuron treatments also reduced live sagebrush canopy cover for at least 9 years.

Several previous Neoproterozoic microfossil diversity studies yield evidence for arelatively sudden biotic change prior to the first well‐constrained Sturtian glaciations. In an event interpreted as a mass extinction of eukaryotic phytoplankton followed by bacterial dominance, diverse assemblages of complex acritarchs are replaced by more uniform assemblages consisting of simple leiosphaerid acritarchs and bacteria. Recent data from the Chuar Group of the Grand Canyon (770‐742 Ma) suggest this biotic change was caused by eutrophication rather than the direct effects of Sturtian glaciation; evidence includes total organic carbon increases indicative of increasing primary productivity followed by iron speciation values that suggest sustained water column anoxia. A new data set (this study) suggests that this same eutrophication event may be recorded in shale units of the formation of Hades Pass and the Red Pine Shale of Utah’s Neoproterozoic Uinta Mountain Group (770‐742 Ma). Results of this study include a significant shift from a higher‐diversity (H’= 0.60) fauna that includes some ornamented acritarchs to a lower‐diversity (H’ = 0.11) fauna dominated by smooth leiosphaerids and microfossils of a bacterial origin (Bavlinella/ Sphaerocongregus sp.). This biotic change co‐occurs with a significant increase in total iii organic carbon values that directly follows a positive carbon‐isotopic excursion, suggesting increased primary productivity that may have been the result of elevated sediment influx and nutrient availability. Both the biotic change and period of increased total organic carbon values correspond with the onset of an interval of anoxia (indicated by total iron to aluminum ratios above 0.60) and a spike in sulfur concentration. Like those reported from the Chuar Group, these biotic and geochemical changes in the upper Uinta Mountain Group are independent of changes in lithofacies , and they suggest that either a eutrophication event or direct inhibition of eukaryotes by sulfide (or perhaps both) may have been the cause of the biotic turnover. These findings support current correlations between the Uinta Mountain and Chuar Groups, the idea that the biotic turnover preserved in both strata was at least a regional phenomenon, and current models of punctuated global ocean anoxia during mid‐ to late‐Neoproterozoic time. Whether or not this hypothesized eutrophication event was more than regional in extent remains a very interesting question and will certainly be a focus of future research.

This study was conducted at the Ailao Mountain National Natural Reserve (NNR) in natural vegetation described as: Lithocarpus xylocarpus/Castanopsis wattii (Oak /Chestnut association) forest. Study sites were located in the Xujiaba area of the reserve at an altitude of ~ 2450 m with slopes of 10-15 degrees. This type of forest is believed to be unique to the NEAR area. The forest is floristically characterized by multiple families and genera. It has two tall tree layers, a well-developed bamboo (Sinarundinaria nitida) layer and evergreen fern species. Bryophyte, ferns and lichen occur and abundant epiphytic bryophyte is present on tree boles.A number of important aspects of nutrient cycling, including patterns of biomass and nutrient accumulation; nutrient return in litterfall and release from decomposing leaf litter; annual nutrient uptake and retention, and nutrient input and output budgets through hydrological flux in natural Lithocarpus/Castanopsis forest in the reserve, were investigated.This natural forest is characterized by high biomass accumulation of living and dead materials. Trees account for >90 % of total biomass. Dead wood comprises a high proportion (9-41 %) of total stand biomass. The sequence of inorganic nutrient element content decreased in the order leave s>b ranche s>roots> stems. Elemental content of the total stand decreased in the order of C>Ca>N>K>AI>Mg>P>Fe>Mn. The elements C, Ca and N were mainly in stems while AI and Fe were mainly in roots.Litterfall was sampled using traps during the period 1991-1999. High variations in litter production between years were associated with masting years of canopy species, and exceptional physical events (strong winds and snow). The mean annual litterfall is 7.12 t ha-1 with a bimodal seasonal pattern in litterfall: the main litterfall peak occurred in April-May and a lesser one in October-November. Woody ++ / litter and reproductive parts contribute relatively high proportions in this natural forest compared with other montane forests. Woody litter had low N and P concentrations compared with the leaf and reproductive parts. Elements return to the soil through small litterfall decreases in the order C>N>Ca>K>Mg>Mn>AI>P>Fe.The standard litter-bag technique was used to determine decomposition of leaf litter from three dominant canopy species (L. xylocarpus, L. chintungensis, C. wattii), one dominant understory species (the bamboo S. nitida) and a mixture of dominant bryophytes between Nov. 1997 and Oct. 1999. In each case, fast initial litter decomposition was followed by lower rates. Decomposition rates of canopy species and bamboo leaf litter appear to be controlled by initial concentration of lignin, N and P more than by morphological features of the leaves. P seemed to limit decomposition of all leaf litter, both initially and later. Nutrient release from decomposing leaf litter is in the order of K>Mg>Ca>N>P>~Fe, except for bamboo (S. nitida) K>Ca> P>N>Mg>Mn>Fe.Nutrient fluxes in bulk precipitation, throughfall and stemflow were measured in the natural forest between Jan. 1998 and Dec. 1999. This forest exhibited low interception by the canopy (13 % of total rainfall). N, P, Ca and S annual throughfall inputs were mainly from precipitation, while most of the K and two thirds of the Mg throughfall input was due to canopy leaching. There were significant effects of epiphytes on the amount and chemical composition of stemflow. Water volume and annual amounts of N, Ca and Mg were reduced, while K, P and S 1 were increased in stemflow after removing epiphytes on boles and branches.Plot- and catchment level approaches were applied to determine nutrient output from the ecosystem during the study period. The results indicated that this catchment has a subsurface flow system. ++ / The amounts of percolation water varied with soil depths. Concentrations of all nutrient elements studied were greater in surface water than in soil solution and stream water. The budgets for all nutrient elements between atmospheric inputs and outputs by both seepage and stream flow were positive, except for calcium (negative).This forest appears to be characterized by relatively high nutrient return (5.6-8.0 % of the total storage) and low nutrient retention (2.0-2.7 % of the total storage). The relative rate of nutrient cycling occupies an intermediate position between temperate evergreen broad-leaved forest and tropical montane rain forest, it is closer to montane rain forests in rates of nutrient circulation.

Doctor of Philosphy (PhD) / This thesis describes the work carried out during four treks, each over 10-11 days, from 1400m to 5000m in the Nepal Himalaya and further work performed during several two-night sojourns at the Barcroft Laboratory at 3800m on White Mountain in California, USA. Nineteen volunteers were studied during the treks in Nepal and seven volunteers were studied at White Mountain. All subjects were normal, healthy individuals who had not travelled to altitudes higher than 1000m in the previous twelve months. The aims of this research were to examine the effects on sleep, and the ventilatory patterns during sleep, of incremental increases in altitude by employing portable polysomnography to measure and record physiological signals. A further aim of this research was to examine the relationship between the ventilatory responses to hypoxia and hypercapnia, measured at sea level, and the development of periodic breathing during sleep at high altitude. In the final part of this thesis the possibility of preventing and treating Acute Mountain Sickness with non-invasive positive pressure ventilation while sleeping at high altitude was tested. Chapter 1 describes the background information on sleep, and breathing during sleep, at high altitudes. Most of these studies were performed in hypobaric chambers to simulate various high altitudes. One study measured sleep at high altitude after trekking, but there are no studies which systematically measure sleep and breathing throughout the whole trek. Breathing during sleep at high altitude and the physiological elements of the control of breathing (under normal/sea level conditions and under the hypobaric, hypoxic conditions present at high altitude) are described in this Chapter. The occurrence of Acute Mountain Sickness (AMS) in subjects who travel form near sea level to altitudes above 3000m is common but its pathophysiology not well understood. The background research into AMS and its treatment and prevention are also covered in Chapter 1. Chapter 2 describes the equipment and methods used in this research, including the polysomnographic equipment used to record sleep and breathing at sea level and the high altitude locations, the portable blood gas analyser used in Nepal and the equipment and methodology used to measure each individual’s ventilatory response to hypoxia and hypercapnia at sea level before ascent to the high altitude locations. Chapter 3 reports the findings on the changes to sleep at high altitude, with particular focus on changes in the amounts of total sleep, the duration of each sleep stage and its percentage of total sleep, and the number and causes of arousals from sleep that occurred during sleep at increasing altitudes. The lightest stage of sleep, Stage 1 non-rapid eye movement (NREM) sleep, was increased, as expected with increases in altitude, while the deeper stages of sleep (Stages 3 and 4 NREM sleep, also called slow wave sleep), were decreased. The increase in Stage 1 NREM in this research is in agreement with all previous findings. However, slow wave sleep, although decreased, was present in most of our subjects at all altitudes in Nepal; this finding is in contrast to most previous work, which has found a very marked reduction, even absence, of slow wave sleep at high altitude. Surprisingly, unlike experimental animal studies of chronic hypoxia, REM sleep was well maintained at all altitudes. Stage 2 NREM and REM sleep, total sleep time, sleep efficiency and spontaneous arousals were maintained at near sea level values. The total arousal index was increased with increasing altitude and this was due to the increasing severity of periodic breathing as altitude increased. An interesting finding of this research was that fewer than half the periodic breathing apneas and hypopneas resulted in arousal from sleep. There was a minor degree of upper airway obstruction in some subjects at sea level but this was almost resolved by 3500m. Chapter 4 reports the findings on the effects on breathing during sleep of the progressive increase of altitude, in particular the occurrence of periodic breathing. This Chapter also reports the results of changes to arterial blood gases as subjects ascended to higher altitudes. As expected, arterial blood gases were markedly altered at even the lowest altitude in Nepal (1400m) and this change became more pronounced at each new, higher altitude. Most subjects developed periodic breathing at high altitude but there was a wide variability between subjects as well as variability in the degree of periodic breathing that individual subjects developed at different altitudes. Some subjects developed periodic breathing at even the lowest altitude and this increased with increasing altitude; other subjects developed periodic breathing at one or two altitudes, while four subjects did not develop periodic breathing at any altitude. Ventilatory responses to hypoxia and hypercapnia, measured at sea level before departure to high altitude, was not significantly related to the development of periodic breathing when the group was analysed as a whole. However, when the subjects were grouped according to the steepness of their ventilatory response slopes, there was a pattern of higher amounts of periodic breathing in subjects with steeper ventilatory responses. Chapter 5 reports the findings of an experimental study carried out in the University of California, San Diego, Barcroft Laboratory on White Mountain in California. Seven subjects drove from sea level to 3800m in one day and stayed at this altitude for two nights. On one of the nights the subjects slept using a non-invasive positive pressure device via a face mask and this was found to significantly improve the sleeping oxyhemoglobin saturation. The use of the device was also found to eliminate the symptoms of Acute Mountain Sickness, as measured by the Lake Louise scoring system. This finding appears to confirm the hypothesis that lower oxygen saturation, particularly during sleep, is strongly correlated to the development of Acute Mountain Sickness and may represent a new treatment and prevention strategy for this very common high altitude disorder.

Despite many studies describing the physiological characteristics of professional road cyclists and recent work describing the demands of competition, there is a paucity of similar information regarding elite mountain bike (MTB) cyclists. The aim of the present work was to describe the physiological characteristics and the demands of competition for successful MTB cyclists relative to successful road cyclists. Internationally competitive cyclists from both disciplines (seven MTB and seven road) completed the following laboratory tests: anthropometric measurements, an incremental cycle ergometer test and a 30 minute laboratory time trial. In addition, the power output profile obtained in the field from a world-class MTB cyclist riding a simulated race were compared to successful road cycling performances (placing top 3) in flat (FLAT), semi-mountainous (SEMO), high-mountainous (HIMO), individual time trial (ITT) and criterium (CRIT) road races. Due to conversion problems, 6 sentences have been omitted. For full abstract, see 01front.pdf. These results indicate that success in international MTB racing requires high power-to-weight characteristics complemented by a light and lean physique. MTB racing is associated with greater torque at the pedal crank, a more constant effort with less time at lower power outputs and a higher frequency of highintensity surges than road racing. Therefore coaches should take into account these unique MTB racing characteristics when devising training programs for elite athletes.

The following study is an attempt to comprehend the impact that the Canadian-United States border along the forty-ninth parallel had on the Plains Metis between 1869 and 1885, and how members of this community continued to manipulate the border to meet their own objectives. From the 1860s to 1880s, state definitions of Metis status, as well as government recognition and non-recognition of Metis identity, had a profound impact on the Plains Metis. Imposed state classifications and statuses limited the choices of many to enter treaty, be recognised as a citizen, or reside in a partiuclar country. The implementation of these status definitions began after 1875 when the enforcement of the international boundary began in earnest, and it was this endforcement that represented the beginnings of the colonisation of the Plains Metis. / History

Since European American settlement of the Intermountain Region, dramatic changes in vegetation composition and structure have occurred in the sagebrush steppe ecosystem. Western juniper (Juniperus occidentalis spp. occidentalis Vasek), although indigenous to the Intermountain Region, has increased since the late 1800s. Considerable work has been done documenting juniper woodland expansion in the Intermountain West, however, little is known about the environmental variables that influence rates of tree establishment and structural attributes of woodlands across landscapes. Most studies of western juniper have addressed site-specific questions at limited spatial scales. Consequently, there is a lack of research on broader scale patterns of woodland development occurring across heterogeneous landscapes. In addition, changes in the amount, composition, and structure of fuels during the transition from open sagebrush steppe communities to closed juniper woodlands have profound influences on the size, intensity, frequency, and behavior of fire. However, limited data exist quantifying changes in fuels during this transition, thus, consequences to fire behavior have been difficult to predict. The major impetus for the study was to determine the influence of environmental variables on rates and structural attributes of woodland development and associated changes in fuel loading characteristics during the transition from sagebrush steppe communities to closed juniper woodlands in the High Desert and Humboldt ecological provinces. The proportion of trees greater than 150 years old relative to trees less than 150 years suggest western juniper has greatly expanded in the Owyhee Mountains and on Steens Mountain since settlement of the areas. Ninety-five percent of the trees established after the 1850s. As evidenced by the presence of western juniper in 96% of plots sampled in this study, juniper is able to encroach upon a variety of plant alliances and under a broad range of environmental conditions over diverse landscapes. Although it appears the occurrence of western juniper within the woodland belt is not spatially limited by environmental or vegetative conditions, stand structural and fuel loading characteristics do vary considerably across heterogeneous landscapes. Total juniper density, density of dominant trees comprising the primary canopy, and certain live and dead fuels biomass very substantially with site potential. Spatial variation in stand structure and fuels may have significant implications to management of juniper at the landscape scale. / Graduation date: 2005

Graduation date: 1994

Human Monocytic Ehrlichiosis (HME) is an emerging disease first described in 1987 and is transmitted by the bite of Amblyomma americanum. Over the past 10 years, the CDC has documented increasing ehrlichiosis case reports nationwide. Our study site is a golf-oriented retirement community located in the Cumberland Plateau of Tennessee. In 1993, four men at the study site had symptoms consistent with HME which prompted a CDC outbreak investigation and led community managers to mitigate ticks feeding on deer. The objectives of this study were to measure the efficacy of current tick mitigation attempts, to determine the level of infection and composition of tick-borne disease in the study area, and to assess which wildlife species are potentially acting as reservoirs for disease. Ticks were sampled in the community at eight sites of ‘4-poster’ acaricide applicator utilization and at seven untreated sites. Close to the ‘4-poster’ devices, larval, nymphal, and adult tick abundances were reduced by 90%, 68% and 49% respectively (larval p<0.001, nymphal p<0.001, adult p=0.005) relative to the untreated areas. We extracted DNA from A. americanum ticks collected at the treatment and non-treatment sites and tested for Ehrlichia spp. infections. Of 253 adult and nymphal A. americanum tested, we found 1.2% to be positive for Ehrlichia chaffeensis, 4.7% positive for Ehrlichia ewingii, and 1.6% positive for Panola Mountain Ehrlichia; in combination this prevalence is similar to that reported in other Ehrlichia-endemic areas of the eastern U.S.. We also performed blood meal analysis on DNA from A. americanum ticks and the results suggest that the most significant reservoir hosts for Ehrlichia spp. are white-tailed deer, turkeys, grey squirrels, and Passeriformes. We conclude that while the ‘4-poster’ acaricide applicators reduce the number of ticks close to treatment, at the density at which they are currently being used (8 applicators per 52.6 km2, average distance between applicators = 6.6km) they will have no large-scale effect on the community’s tick population. In order to accomplish area-wide reduction of A.americanum and Ehrlichia spp. in this locale, community managers should develop an integrated management strategy that utilizes other techniques in addition to ‘4-poster’ devices.