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Montane ecosystems of the western United States have experienced dramatic changes in their fire regimes over the last 150 years. Fire behavior modeling enables understanding of how ecosystem changes have altered past fire regimes. The Valles Caldera National Preserve in the Jemez Mountains, northern New Mexico, contains one of the largest montane grasslands in North America. This area is used for multiple uses ranging from logging to grazing and recreation. These important ecosystems have experienced increased fuel loads and stem densities resulting from a century of fire exclusion and tree encroachment, resulting in potentially anomalous fire behavior. We investigated whether fire pathways tend to spread along the grassland-forest ecotone or if fire would spread directly across grasslands under extreme fire weather conditions. We used the program FlamMap to model fire behavior under a variety of weather and fuel conditions. Fire spread pathways and burn perimeters were computed for the 50th, 90th, and 99th percentiles of historic weather conditions. The results are compiled into a probability surface that represents the most parsimonious pathways of fire spread in this landscape. We found that pathways were related to the origin of ignition; fires tended to spread around the ecotone, facilitating fire spread to adjacent grasslands. These results, complemented with fire history studies in dendrochronology and empirical observations of the Las Conchas Fire in 2011, further the understanding of the role and dynamics of fire in maintaining the montane-grassland conifer ecotone, and can guide efforts to restore a landscape affected by the effects of fire exclusion.

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Vacuum harvested peatlands do not easily regain their hydrological function after peat production therefore restoration is required to create hydrological conditions appropriate for the growth of peat producing fen plant species. Peat extraction at Bic-Saint-Fabien peatland by the block-cut method began in 1946, converted to vacuum harvesting in the early 1970’s and ceased in 2000. After exploitation, about 0.04-1 m of residual minerotrophic sedge peat remained; therefore Bic-Saint-Fabien was restored as a fen. Research occurred in 2008-2011 and restoration began fall 2009 so we have two pre-restoration and two post-restoration study years. Rewetting consisted of blocking active drainage ditches, contouring the peat surface into level terraces to even out elevation differences, and building peat ridges (bunds) to retain runoff. Vegetation was introduced to some recontoured parts of the site by the surface layer transfer method. A straw mulch treatment was applied to minimize evapotranspiration. A water budget was created for the harvested cutover area and an adjacent undisturbed section of Bic-Saint- Fabien for all study years. Data collection for the water budget occurred June 2-August 7 (day of year 153-219). Water table, volumetric soil moisture content and soil-water pressure were also examined to better understand the impact of reconfiguration on the hydrology of the system. A 1-1.5 m thick layer of gyttja (a low permeability, high porosity lake-bed sediment) underlies the residual peat; it was parameterized and assessed to see if it could potentially compress and supply water to the overlying peat when the system is stressed. In 2011, the volumetric moisture content and thickness of gyttja were monitored in the field to estimate the strain placed on the gyttja by seasonal water table variability. Gyttja samples were collected and brought back to the laboratory for parameterization and compressibility tests. A water budget was completed annually for the cutover and undisturbed areas of the peatland. There were no distinguishable differences between study years except that 2008 and 2009 were climatologically wetter. During the water budget period surface and groundwater run-on into the cutover area were negligible making precipitation the principle water input. The dominant water loss from the cutover area was evapotranspiration since runoff was only 2 and 9 mm in 2010 and 2011, respectively. Rewetting did not result in a uniform wetness across the cutover site chiefly due to local differences in peat surface elevation. An interior section of Bic- Saint-Fabien remained saturated for nearly all of 2011; it had mean seasonal water table of +2.8 cm, and volumetric soil moisture content and soil-water pressure, 5 cm below the peat surface were 86% and +4 mbar. At a peripheral section (~100 m away) the values were -14.4 cm, 67% and -13 mbar, respectively. While the interior was generally wetter than the peripheral regions, there were some exceptions, notably near where dams were installed on peripheral drainage ditches. The markedly different spatial patterns of wetness suggests that a uniform prescription regarding vegetation re-establishment in the rewetted section may not be warranted. The bulk density, particle density and porosity of gyttja averaged 0.12 g cm-3 1.57g cm-3 and 92%, in the top 40 cm of the layer. The organic matter content of gyttja decreased with depth from about 70% at a 5 cm depth to 45% at a 45 cm depth. Laboratory compression tests showed 9 and 72% strain at effective stresses of 3.5 and 200 kPa, respectively, demonstrating the potential for releasing water upon compression, which in the field is caused by water table lowering. From day of year 192 to 202 in 2011, when a ~8 cm water level change occurred (effective stress range ~0.8 kPa), the volumetric moisture content and thickness of the top 30 cm of gyttja decreased by 0.4%, and 0.5 cm, respectively, representing 0.1 and 1.7% strain, respectively, as determined from these two different approaches. The compression of gyttja after Bic-Saint-Fabien was rewetted (2011) was small but might have been significant under drier conditions with greater water table variability, such as during the early stages of site drainage when it was being prepared for peat extraction or after peat production ceased. The release of water to the peat layer from the compression of gyttja after peat production finished and before rewetting occurred, might have been an important self-preservation mechanism, eventually making it easier to rewet. Water table drawdown in 2011 produced very small strain rates suggesting gyttja compression in this year had no important role; hence rewetting success was more reliant on other rewetting techniques implemented at this site.

The context in which we find ourselves at the beginning of the twenty-first century is one of acute environmental degradation. In this thesis, I examine how Christians may respond to the realities of degradation through ecological restoration, an environmental practice aimed at assisting the recovery of ecosystems that have been degraded, damaged, or destroyed, and do so in ways that reflect the core belief in the redemptive purposes of God in Christ for creation. The intention, therefore, is to construct a theological framework for ethical responses to degradation through restoration. I begin by examining ecological restoration as a contested scientific and cultural practice, exploring the questions it raises on the nature of human life, the natural world, and moral action, and evaluating the role of history in shaping moral responses to degradation through restoration. To develop a theological framework for restoration, I engage the work of Christian ethicist Oliver O'Donovan, particularly his text on the foundations of Christian ethics: Resurrection and Moral Order. I ground this framework in his arguments for the resurrection (with its dual movements of restoration and transformation) as the starting point for moral action, for the work of the Holy Spirit who makes God’s redemption a reality that shapes moral action, and for love as the shape of moral action. I draw out the significance for restoration of his moral realist approach, examining the created order and articulating a theological anthropology, and I show how the resurrection of Christ provides a guide for restorative action that both affirms the created order and yet remains attentive and open to its, and our, transformation. Finally, through an examination of love as perceptive and responsive to the natural world, I articulate a vision for restorative action that is oriented toward upholding and preserving the value of the natural world, and attentively and creatively responding to it in ways that bring forth its value so that it may be seen for what it is: the beloved world that God has affirmed and redeemed in the resurrection and which awaits its fulfilment.

Restoration seeks to heal the environment and make amends for damages done by human interference. Preservationists, however, claim that restoration is anthropocentric, hubristic, and ultimately misguided. I defend restoration against these criticisms, and examine narratives from Karl Marx and Lynn White, Jr. to explain human alienation from nature. I use a synthesis of lessons from Marx and White to favor a restoration paradigm over a preservationist model.

It is the purpose of this thesis to examine and compare three Restoration and eighteenth century adaptations of Shakespeare's Measure for Measure: William Davenant's The Law Against Lovers, acted in 1662; Charles Gildon's Measure for Measure: or, Beauty the Best Advocate, acted in 1700; and John Philip Kemble's Shakspeare's Measure for Measure, acted in 1794. The plays are discussed with regard to their divergence from Shakespeare's play. In addition, they are examined from the standpoint of their ability to reflect the theatrical practices, audience preferences, and social conditions of the time in which they were performed.

As the ecological importance of prairies is becoming more recognized, the number of prairie restoration projects is increasing worldwide. One of the major challenges in restoring any disturbed ecosystem is the successful establishment of native species at the expensive of invasive species. While some weedy species are gradually replaced as other, more desired, species become established, there are invasive species that, due to their level of dominance, may out-compete native species indefinitely. The objectives of this study were 1) to quantify the impact of Ambrosia trifida (giant ragweed) on the plant community of a newsly established prairie, 2) to assess any difference in effectiveness between management practices (cutting versus pulling) of A. trifida, and 3) to establish a baseline vegetation survey to be used in future evaluations and research of the prairie. In March of 2011, 30 plots (each 3 m2) were established within the 20 acre prairie including 10 control plots [C], 10 plots where A. trifida was selectively cut approximately 10 cm above ground level [Rc], and 10 plots where A. trifida was selectively pulled [Rp]. Treatment (cutting/pulling) was applied three times (April, June, and August) during the study, and in order to compare the effectiveness of the treatments, the number of removed A. trifida was recorded for the first two applications. Between April and June, the number of A. trifida decreased by a mean of 34.9 individuals in the cut plots, and increased by a mean of 12.4 individuals in the pulled plots suggesting (albeit, not significantly) that pulling may disturb the ground and promote the germination of more seeds from the seedbed. Final biomass data collection was conducted in mid August by removing the above ground biomass of all plants excluding A. trifida from four subplots within each of the 30 main plots, followed by drying and weighing of all biomass. A total of 172 plants from 30 species were removed for a total biomass of 1735.10 grams. In the control plots the mean biomass was 6.73g and the species diversity (H') was 0.037. In the treatment plots, the corresponding values were 83.39g, and 2.093. This twelve-fold difference in biomass suggests that the presence of A. trifida has a remarkable impact on the overall community of this newly established prairie and that the correct management of A. trifida could expedite the restoration process.

Thesis advisor: Noah P. Snyder / Centuries-long intensive land use change in the northeastern U.S. provides the opportunity to study the response timescale of geomorphic processes to anthropogenic perturbations. In this region, deforestation and the construction of dams following European settlement drastically altered the landscape, leading to the impoundment of sediment in mill ponds. This legacy sediment continues to be released into transport decades after a dam has been removed or breached. Geochemical tracers can help distinguish sediment sources and understand how sediment moves through a watershed. The South River in western MA is located in a formerly glaciated watershed, and these surficial deposits compose 98% of the area. It experienced two generations of damming, beginning with smaller mill dams in the 18th-19th centuries, followed by the construction of the Conway Electric Dam (CED), a 17 m tall hydroelectric dam in the early 20th century. Legacy sediment deposits from sediment stored behind mill dams cover 1.5% of the watershed area. The CED is located near the outlet of the river, providing a century-long depositional record for the watershed, during reforestation. I hypothesize that sediment mobilized from human activity will contain a different geochemical signature than glacial material, that recent erosion in the watershed is primarily from anthropogenic legacy deposits rather than from glacial age landforms, and channel widening is occurring in reaches of the channel composed of legacy sediment, rather than in glacially confined reaches. These hypotheses were tested through a two part investigation, consisting of a sediment tracing study using Hg, and a Geographic Information Systems (GIS) analysis of channel changes using aerial photographs from 1940 and 2014. Samples were collected from river bank exposures of 11 glacial deposits and four mill pond legacy sites. Two vibracores measuring 476 and 500 cm were collected in reservoir sediment stored behind the CED in 2013 and 2017, respectively. Hg concentrations range from 1-4 ppb in glacial sediment, 3-380 ppb in legacy sediment, and 2-18 ppb and 7-50 ppb in the two CED cores. I used Hg as a tracer to estimate percent contributions to the CED reservoir from each watershed source during the 20th century. Results from a sediment mixing model suggest glacial sources contributed 32 ± 15%, and legacy sediment deposits contributed 68 ± 15% during the 20th century. Based on 137Cs dates on the cores, high amounts of legacy sediment filled in behind the CED prior to 1953 (74 ± 35 %), and background erosion from glacial deposits dominated from 1953 until the reservoir was filled in the 1980s (63 ± 14%). GIS analyses using aerial photographs from 1940 and 2014 indicate that the channel did not significantly widen along any section of the river, however, increases in sinuosity (up to 12%) occurred in the legacy sediment dominated reaches of the channel, and minor increases (1-2%) occurred in the glacial reaches. Overall, these analyses show an increase in the amount of sediment released in the channel as a result of mill dams breaching through the mid-19th to early 20th centuries, and suggest a short recovery timescale response from this land-use change. / Thesis (MS) — Boston College, 2018. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Earth and Environmental Sciences.