Under normative conditions the mountain pine beetle (Dendroctonus ponderosae Hopkins) has played a regulating role in healthy lodgepole pine (Pinus contorta) forests. However, recently eruptive outbreaks that result from large pine beetle populations have destroyed vast tracts of valuable forest. The outbreaks in North America have received a great deal of attention from both the timber industry and government agencies as well as biologists and ecologists. In this dissertation we develop a landscape-scaled integrodifference equation model describing the mountain pine beetle and its effect on a lodgepole pine forest. The model is built upon a stage-structured model of a healthy lodgepole pine forest with the addition of beetle pressure in the form of an infected tree class. These infected trees are produced by successful beetle attack, modelled by response functions. Different response functions reflect different probabilities for various densities. This feature of the model allows us to test hypotheses regarding density-dependent beetle attacks. To capture the spatial aspect of beetle dispersal from infected trees we employ dispersal kernels. These provide a probabilistic model for finding given beetle densities at some distance from infected trees. Just as varied response functions model different attack dynamics, the choice of kernel can model different dispersal behavior. The modular nature of the Red Top Model yields multiple model candidates. These models allow discrimination between broad possibilities at the land scape scale: whether or not beetles are subject to a threshold effect at the lands cape scale and whether or not host selection is random or directed. We fit the model using estimating functions to two distinct types of data: aerial damage survey data and remote sensing imagery. Having constructed multiple models, we introduce a novel model selection methodology for spatial models based on facial recognition technology. Because the regions and years of aerial damage survey and remote sensing data in the Sawtooth National Recreation Area overlap, we can compare the results from data sets to address the question of whether remote sensing data actually provides insight to the system that coarser scale but less expensive and more readily available aerial damage survey data does not.

Ninety-four unmanaged lodgepole pine stands were examined to evaluate the relationship between stand density and susceptibility to mountain pine beetle attack. Sample included stands from a broad geographical range in the western United States. Beetle population trends were not significantly related to variation in stand density as measured by stand density index (SDI). The percentage of trees killed per acre by the mountain pine beetle in stands with greater than eighty percent lodgepole pine did vary significantly with changes in SDI. From these data three SDI zones were identified: 1) stands with SDI's of less than 125 showed low potential for attack, 2) stands between 125 and 250 SDI showed much greater levels of tree mortality, gradually decreasing toward the 250 SDI, 3) tree mortality decreased in stands as density increased beyond the 250 SDI value.

“Perilous Pilgrimage: A Lady’s Flight into the Rocky Mountain Wilderness” is comprised of four thematically linked essays set in the Colorado Rockies. In these essays I probe my fascination with masculinity at an early age, the impact of my rape at age twenty-two, the dependency and resentment that undermined my marriage after the rape, and my quest after my divorce fifteen years later to define myself on my own terms. The link joining these strands is the tension between my drive for independence and my disassociation from my mind and body as a result of the rape. “Perilous Pilgrimage” revisits three pivotal stages of my life: childhood, young adulthood, and middle age. As a youngster vacationing with my family in Rocky Mountain National Park, I was drawn to men who rescued lost hikers and climbed mountains. Fred Bowen, the caretaker of our rented cabin in the park, and the two California school teachers who were the first to conquer the Diamond on Longs Peak, appeared to have more freedom than I did as a middle-class girl growing up in the 1950s. That conviction was reinforced after I moved to Colorado at age seventeen. Four years later I graduated from college and began dating a man who introduced me to the thrill and terror of mountaineering. After leading me up numerous mountains, he became my husband, and we made our home in Manitou Springs, Colorado. Once married, I could no longer repress the unresolved issues of my rape and identity quest, and I revolted. At age thirty-nine, I embarked on a solo quest to reclaim that sense of wonder and independence I had felt as a child exploring Rocky Mountain National Park. Included in my essays are references to historical figures with similar urges as mine, such as the 19th-century English explorer George Augustus Ruxton and English travel writer Isabella Bird. My search for refuge and redemption in the Colorado Rockies replicated a centuries-old pattern.

Practical assessments of range production and utilization are based on forage weight estimates. In preparing these estimates moisture content in green vegetation offers some problems. The moisture component is not likely to be constant for a given species. Diurnal, seasonal and site variability have been well illustrated for agronomic and tree species (Salisbury, 1848; Jenkins, 1879; Miller, 1917; Pearson, 1924; Watkins, 1940; Parker, 1951; Ackley, 1954; Werner, 1954; Zohary and Orshan, 1956; Slatyer, 1959; Kozlowaki, 1965 and Jame son, 1966). Since variability is also likely for range plants, computations made on green weights are apt to be fallacious. It is a common practice, therefore, to express production on "water free" or "dry weight" basis. But the estimates of dry weight are made difficult by variations in herbage moisture. A variety of factors, relevant both to the vegetation and the site it occupies, would seem to account for variable moisture content. The prevalent methods for estimating moisture, however, seem to be more of a legacy from the past than an appreciation of ecological influences. Earlier investigators of pastures and fodder crops were largely agronomists interested in comparing yields. They were concerned primarily with irrigated crops where soil moisture is not a limiting factor and the ecological influences, such as humidity, rain, cloudy weather, dew, shade, exposure etc. are far from dominant (Atwater, 1869; Collier, 1881; Richardson , 1884; Ladd, 1888; Richardson, 1889; Morse, 1891 and Widstoe, 1897). The variations in water content and other components were accordingly related to stage of growth. Taking a cue from these studies agencies such as the United States Forest Service and Soil Conservation Service came to use certain reducing factors to convert green weight of range forage into dry weight. In developing these factors the type of vegetation and growth phases have been considered but ecological features and context have been neglected. The methodology adopted from pasture conditions became the accepted basis for making range management decisions (Range Memo, SCS-8, Soil Conservation Service, 1963; Range Analysis, Region IV, Forest Service, 1964). The influence of features of environment, particularly aspect, on growth differential, has long been recognized by foresters (Schlich, 1905; Champion, 1928 and Tourney, 1928). Plant physiologists have been aware of the significance of time-of-day on plant water for some time (Shreve, 1914; Miller, 1917). It is very probable that these influences express themselves in moisture content of herbage also. The investigations reported herein were conducted to define and assess the scope and intensity of some of these ecological features in modification of the moisture component of herbage. The objective is to determine whether differences in ecological context influence range herbage moisture to a sufficient extent to warrant consideration in developing conversion factors for deriving dry weights from green weights of vegetation samples. The appraisal should reaffirm present assumptions applied or yield more accurate adjustments for estimating forage production. In either circumstance the results should enhance the scientific basis of range management decisions.

The Nounan Formation in north-central Utah thickens northward from 696 feet near Causey Dam to 1147 feet at High Creek in the Bear River Range, and northwestward to 1149 feet at Dry Canyon in Wellsville Mountain. The basal contact of the Nounan Formation is sharp, but dolomite extends irregularly downward into limestones of the Bloomington Formation as much as 6 feet. The Nounan Formation is divided into three members based on lithologic characters: (1) a lower member composed of dark, medium-crystalline dolomite; (2) a middle member composed of white, coarse-crystalline dolomite with tongues of dark dolomite; and (3) an upper member of interbedded light and dark dolomites and limestones with local arenites and sandy carbonates. The lower member was deposited in a high-energy, shallow-marine subtidal to intertidal environment. Evidence includes sets of low-angle cross stratification (dunes), oncolites, oolites, and rip-up clasts. The middle member forms distinctive ledges and cliffs. The presence of thinly laminated algal stromatolites and relict structures seen also in the lower member indicate a subtidal to intertidal environment similar to that inferred for the lower member. The white color and coarse crystallinity may have resulted from recrystallization of the dark, finer grained dolomite that comprises the lower member. The upper member is characterized by lithologic variability. Thicknesses of limestone are greatest in the north, and decrease to only a few feet in the south. Quartz and other terrigenous minerals are scattered at intervals throughout the upper member, with a marker of sandy (arenaceous) dolomites at the base and near the middle and an increase of sand near the top also. The upper contact, with quartz-rich arenites (subarkosic quartzites) of the Worm Creek Member of tho St. Charles Formation, is gradational overall, but is sharp and planar in each section and readily located. In the upper member, algal mats trapped a varying but overall increasing influx of quartz and feldspar, probably in shallow subtidal environments, and vertically stacked hemispheroids suggest that depositional conditions may have included intertidal. Virtually all of the dolomite in the Nounan Formation must have formed by replacement of lime sediments by downward-moving high-magnesium brines. It is that these brines originated in restricted, shallow, subtidal evaporating basins, such as the Great Bahama Banks today, and associated supratidal flats. Lateral changes from limestone to dolomite overall and also in individual beds of the upper member indicate that the brines travelled laterally as well as vertically, and dolomitization may have been limited as much by prior diagenetic alteration and cementation as by the volume, concentration, and proximity of the brine itself.

Comprehensive population studies in the field of fisheries are in great demand. Many of our fishable waters are being changed, and we need to be able to predict the results of these habitat alterations. We must know how to include beneficial modifications in readjustments of habitat in order to create a fishery or prevent destruction of an existing one. The acceptable situations for good fish production in large mountain streams are not well-knowno A fishery can be properly managed only if the manager has sufficient knowledge of the carrying capacity of the habitat, the survival and mortality of the population, and the movements of the fish within the population. My study is an attempt to answer some of these questions about the self-sustaining populations of brown trout (Salmo trutta fario Linnaeus) and mountain whitefish (Prosopium williamsoni Girard) in a 5-mile section of Logan River, Utah.

Mountain pine beetle (Dendroctonus ponderosae Hopkins) has caused extensive tree mortality in whitebark pine (Pinus albicaulis Engelm) forests. Previous studies conducted in various conifer forests have shown that fine surface fuels are significantly altered during a bark beetle outbreak. Bark beetle activity in conifer stands has also been shown to alter foliar fuel moisture content and chemistry over the course of the bark beetle rotation.The objective of this study was to evaluate changes to fine surface fuels, foliar fuel moisture and chemistry and litter chemistry in and under whitebark pine trees infested by mountain pine beetle. Fuels were measured beneath green (healthy) trees compared to red (two years since initial MPB attack with 50% or greater needles remaining) and gray (greater than two years since attack with between 15% and 45% needles remaining) trees. Foliar moisture content was measured in four mountain pine beetle crown condition classes: green-uninfested, green-infested (current year’s attack), yellow (last year’s attack), and red. Total terpene content was analyzed in whitebark pine needle litter and volatile terpenes were collected and analyzed from green, green-infested, yellow, and red trees.Significant differences were found in litter depths under green, red, and graytrees. Duff depths were significantly less beneath green trees than red and gray trees. One hour and ten hour fuels were more influenced by diameter and crown size than beetle crown condition classes. Foliar fuel moisture content dramatically decreased from green-infested to the red beetle crown condition class. No differences were detected in shrub and forb biomass between green, red, and gray trees. Green-infested trees had significantly lower foliar fuel moisture than green trees and by late in the season showed fuel moisture levels similar to red trees which had the lowest fuel moisture content. Litter beneath red trees contained large amounts of terpenes, including compounds known to increase foliage flammability that remain in the litter throughout the fire season. Total terpene content emitted from red foliage is greater than green-infested or yellow foliage.

Studies of predator-prey and predator-predator interactions are needed to provide information for decision-making processes in land management agencies. Mountain lions (Puma concolor) are opportunistic carnivores that prey on a wide variety of species. In the Sierra National Forest, CA, they have not been studied since 1987 and their current interactions with their prey and other predators are unknown. Forest managers in this region are concerned with declines of fishers (Pekania pennanti) and studies have shown intraguild predation to be a leading cause of fisher mortality in this area. Managers are interested in learning more about mountain lion predation patterns with regard to prey preference, but also how lions traverse and use the landscape and how anthropogenic activities may be increasing lion predation risk on fishers. Using GPS radio-collar technology, we examined mountain lion kill rates and prey composition at 250 kill sites. We found mule deer (Odocoileus hemionus) to be their main source of prey (81%) with gray foxes (Urocyon cinereoargenteus) comprising 13.2% of prey composition. We did not detect any fisher predation during our 2-year study; however, during our study, the Kings River Fisher Project experienced extremely low juvenile fisher survival. To gain a better understanding of seasonal resource selection by mountain lions, we developed resource selection functions (RSF) while they were moving through the landscape and when killing prey. We developed RSF models for all data across the study area, as well as, for a subset of data encompassing an area where LiDAR (Light Detection and Ranging) data had been collected. Within the LiDAR study area, we digitized unmapped roads and skid trails using a Bare Earth data set. We found mountain lion ‘moving’ locations showed selection for close proximity to streams during summer months and selection for ruggedness and steeper slopes during both summer and winter. With 3 of the 4 RSF models at kill sites showing high risk of predation within close proximity to either digitized roads/skid trails or mapped roads, we recommend managers map all anthropogenically created linear landscape features and consider restoring these linear features to pre-treatment landscape conditions following timber harvest.

Geothermal energy is being explored as a supplement to traditional fossil fuel resources to meet growing energy demand and reduce carbon emissions. Geothermal energy plants harvest heat stored in the Earth’s subsurface by bringing high temperature fluids to the surface and generating steam to produce electricity. Development of geothermal resources is often inhibited by large upfront risk and expense. Successful mitigation of those costs and risks begins with efficient characterization of the resource before development. A typically successful geothermal reservoir consists of a fractured reservoir that conducts hydrothermal fluids and a cap rock seal to limit convective heat loss through fluid leakage. The controls on the system include the density and orientation of fractures, mechanical rock properties, and the local stress field acting on those rocks. The research presented in this dissertation utilizes diverse data sets to characterize core, wireline borehole logs, and laboratory data to describe the distribution of fractures, rock properties, and the orientation and magnitude of stresses acting on the borehole. The research demonstrates there is a potential resource in the region and describes the controls on the vertical extent of the hydrothermal fluids. The distribution of fractures is controlled by the distribution of elastic rock properties and rock strength. A cap rock seal is present that limits hydrothermal fluid loss from a fractured artesian reservoir at 1,745 m (5,726 ft). In addition to characterization of the resource, this research demonstrates that an equivalent characterization can be used in future exploration wells without the expense and risk of collecting core. It also demonstrates that multiple methods of analysis can be utilized simultaneously when some data are not available. Data collection from deep wellbores involves risk and data loss or tool failure is a possibility. In these cases, our methods show that successful characterization is still possible, saving time and money, and minimizing the financial risk of exploration

A study to determine habitat differences of benthic macroinvertebrates was conducted on the upper Strawberry River, Utah. The investigation was part of a large scale project to determine minimum stream flow requirements for trout. The effects of time, habitat, depth and velocity on the distribution of benthic fauna were evaluated. Samples of benthic invertebrates (146 total) were collected every 2 months at 8 stations on the river from November, 1975 through August, 1976. Representatives of 59 taxa were collected. Eight taxa comprised 90 percent of the mean annual community standing crop in numbers. Biomass was not dominated by any group of taxa. Community standing crop decreased from late Fall 1975 until early Summer 1976. The largest increase in standing crop occurred during August. Prediction of benthic distribution through the use of depth and velocity categories was unsuccessful. Three-dimensional plots of the relative density of a taxon versus depth and velocity indicated the contagious nature of the animals' distributions but their preference for specific categories could not be demonstrated. The results suggested that macroinvertebrates could tolerate large variations in current and depth and that these physical factors are only indirectly related to faunal distribution. Results of analysis of variance and covariance showed time to be the factor which influenced the distribution of most taxa (85%), followed by the time x habitat interaction (20%), velocity (18%), habitat (11%), and depth (9%). Comparisons in animal abundance were made between 4 riffles and 4 ''pools". These two habitats did not differ significantly in substrate type or velocity, however depth did show significant differences. Results of nonparametric tests suggested that the majority of taxa migrated into "pools" during periods of snow, ice, and low flows, an indication that "pools" may provide refuge to macroinvertebrates during periods of stream dewatering and diversion.