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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

MAPPING THE DISTRIBUTION AND ABUNDANCE OF WESTERN LARCH (LARIX OCCIDENTALIS NUTT.) WITH MULTI-TEMPORAL SATELLITE IMAGERY AND GRADIENT MODELING.

Touzel, Steven Joseph 18 September 2013 (has links)
Western larch (Larix occidentalis Nutt.) is one of three native North American larch species, it occupies the mountainous regions of northwestern North America, and it is a deciduous conifer. Western larch is among the most ecologically and economically important conifer tree species in the northern Rockies region. This study explores the viability of mapping western larch via the analysis of multi-temporal Landsat imagery and gradient modeling. Larch presence and abundance data from 300 field plots correlated with Normalized Difference Vegetation Index seasonal change (NDVIsc) explains 46% of the variability in larch basal area. Multivariate models built with NDVIsc and additional climatic and topographic variables only slightly improved the models. These satellite imagery based models suggest that western larch tends to occur primarily on shaded, north-facing slopes within the study area. This analysis was contrasted with a gradient modeling approach using data from 4800 Forest Inventory and Analysis plots and a suite of fine scale (30-60 m) topographic and climatic data as predictors. These models correctly predicted larch presence with error rates of less than 20%. Presence or absence of western larch was found to be strongly dependent on minimum temperature and water balance variables (soil moisture deficit and actual evapotranspiration). Probability prediction rasters produced with these data also showed a noticeable northern aspect tendency. The accuracy of the remote sensing based models suggest that the method may be applied to other areas, and the output from both model types points to a strong relationship between larch presence and fine scale topographic and climatic factors, especially as they interact to affect soil moisture.
2

How Ch-paa-qn Got It's Name: A Sixth-Grade Geography Curriculum Unit for Indian Education for All in Montana

Nellis, Mary Elizabeth 18 September 2013 (has links)
Nellis, Mary, M.A., Summer 2013 Geography How Ch-Paa-Qn Got Its Name: A Sixth-Grade Geography Curriculum Unit for Indian Education for All in Montana Chair: Sarah J. Halvorson This thesis reports on the design and implementation of a sixth-grade geography curriculum based on Montana House Bill 412 (HB412), a bill whereby the legislature mandated the removal of the word squaw from public places in Montana. The framework for this unit is founded on place-based education principles and is tailored to fit within the concepts of Indian Education for All as mandated in the Montana State Constitution. Furthermore, as a place-based unit created for students in Missoula, Montana, a primary focal point was Ch-paa-qn Peak, a 7996 foot peak located in Missoula County and the first site in Missoula County to be renamed. The aims of this project were three-fold. First, the curriculum unit was designed to broaden the students understanding of how places get their names, how these names end up on maps, and how HB 412 was instrumental in changing the names of 76 sites in Montana. Second, the intention was to guide students to think about the concept of place, and how names reflect the various ties that people have to the places in which they live. The third aim was to provide middle school teachers statewide with field-tested curricula that support the mission of Indian Education for All, an effort by the State of Montana to incorporate Native history and worldview into all areas of public education.
3

Comparison of Wild-Domestic Sheep Interaction Policies in Bighorn Disease Outbreak Locations in the Continental U.S., 1990-2010

Howard, Tristan 23 May 2013 (has links)
For over 100 years, disease has significantly limited bighorn sheep (Ovis canadensis) in the western U.S. Interaction with domestic sheep (Ovis aries) has been a primary cause of fatal bighorn disease (typically pneumonia), which has severely reduced or eliminated entire populations. Various wild-domestic sheep interaction policies exist to address the disease problem. In this analysis, six case study locations are compared and analyzed in an effort to evaluate policy efficacy. Locations examined and their bighorn die-off dates include: the Tobin Range, NV (1991); Aldrich Mountain, OR (1991); the Highland/Pioneer Mountains, MT (1994-1995); the Tarryall/Kenosha Mountains, CO (1997-2000); the Hays Canyon Range, NV (2007); and Bonner/West Riverside, MT (2010). Each location is investigated based on the policy analysis criteria of: buffer zones, herder supervision rules, trailing restrictions, consideration of domestic sheep presence prior to bighorn reintroduction, grazing allotment alteration efforts, education/negotiation attempts, fatal removal of bighorns near domestic sheep, coordination/tension between agencies, and funding difficulties. Regarding wild-domestic sheep interaction, all locations lacked clear buffer zones and trailing restrictions. At least five locations lacked funding difficulties. Where applicable, in four locations, domestic sheep presence was considered before reintroducing bighorns. In at least two locations, grazing allotment alteration was attempted, and bighorns were fatally removed. In at least five locations, agencies coordinated bighorn management, and negotiation or education was attempted. Tension between agencies existed in at least one location. From 1990-2010, the wild-domestic sheep disease issue gained prominence in policy documents, politics, and in the minds of agency biologists. This projects case studies illustrate that bighorn-domestic sheep interaction policies can be successful with diligence, but success is unpredictable and location-dependent. If bighorns and domestic sheep are to coexist in the same areas, one size-fits-all separation policies covering the entire American West will not be effective. In a strictly ecological context, not allowing domestic sheep and bighorns to share the same ranges at all is the least risky and most effective way to prevent bighorn die-offs caused by domestic sheep disease.
4

An Evaluation of Trend and Anomalies of Arctic Sea Ice Concentration, 1979-2006

Xia, Peiyao 10 May 2013 (has links)
As a part of the Cyrosphere ecosystem, Arctic sea ice is one of the focal points when studying Arctic climate change. Arctic sea ice image has been documented by remotely sensed data since the 1970s. By examining these data, some climate patterns can be revealed. In this research, Arctic region is divided into 9 sections to analyze the regional differences of the ice coverage and variability. Data used are bootstrapped 1979 to 2006 SSM/I and SMMR images from NSIDC to perform a time series analysis to examine the sea ice trends and spatial/temporal anomalies detection by conducting a descending sort of sea ice coverage by years in the sub-regional scale. Then, the temporal mixture analysis developed by Piwowar & LeDrew is applied to the data to reveal the variability within each subregion. Fractional images produced by TMA highlight the temporal signature concentration in the entire Arctic region. And the color-mix image derived from TMA highlights and overlaps temporal signatures that have over 80% concentrations from highest to lowest. The color mix image can reveal the spatial distribution of similar temporal characteristics and the evolution of time series in the same area during the 30-year period. Through this analysis, the spatial and temporal variability of Arctic sea ice can be perceived that in the subpolar regions, Arctic sea ice has a higher seasonal pattern which varies a lot each other. The Arctic sea ice extent endures an overall decline trend, which the decline speed increases every ten years. But this trend is not statistically significant in every subregion. The spatial/temporal anomaly analysis reveals several patterns of Arctic sea ice variability. The seasonal variability of Arctic sea ice in the eastern and western side of the Arctic Basin resemble each other in the long term, which may coincide with the North Atlantic Oscillation. In addition, within a subregion, different areas may have significantly different temporal characteristics, such as the Greenland Sea and Seas of Okhotsk. Moreover, the temporal characteristics some areas in the Arctic region have changed through time significantly regarding early melt or late freeze. Hopefully this analysis will provide undiscovered temporal evolution through time and some new insights on the dynamics of the Arctic sea ice cover.
5

Land-cover change within the peatlands along the Rocky Mountain Front, Montana: 1937-2009

Milbrath, Joseph Tyler 28 June 2013 (has links)
Aerial photographs of nine peatlands along the Rocky Mountain Front, Montana, were analyzed in a GIS. The boundary of wetland extent was hand-digitized and the area within was classified into land-cover types including: total area, open fen, open water, woody vegetation, and non-wetland/agriculture. Changes in wetland extent and land-cover categories were evaluated from the earliest available imagery in 1937 to the last available imagery in 2009. Images prior to 1995 were orthorectified to correct inherent distortions. Results indicate little change in overall peatland area between 1937 and 2009 despite increasing air temperatures in the region. Open water area and the number of ponds increased over the study period, reflecting a rebounding beaver population. Agriculture in Pine Butte Fen, McDonald Swamp, and the Blackleaf Wetland Complex declined over the study period. Land purchases by the Nature Conservancy of Pine Butte Fen and McDonald Swamp have preserved the natural state of those peatlands, and they hold conservation easements for three of the other fens. One peatland is owned by the state and another is located within the Lewis and Clark National Forest. Conversely the sprawling Theboe Lake wetland has been heavily disturbed by ongoing agriculture since prior to 1937, and Bynum wetland has been heavily impacted since the middle of the study period.
6

The effects of water table draw-down on the hydrology of a patterned fen peatland near Quebec City, Quebec, Canada

Whittington, Peter January 2005 (has links)
Hydrological response to climate change may alter the biogeochemical role that peatlands play in the global climate system, so an understanding of the nature and magnitude of this response is important. Simple hydrological models have predicted the effects of climate change on the hydrology of these systems, and estimated a ~20 cm water table draw down. This draw down amount was modeled to estimate the changing role that wetlands may play in global biogeochemical cycling, but failed to account for modifications of the peatland structure, which has profound implications for the hydrology of these systems. Volume change in compressible soils occurs as the result of different processes, mainly compression and oxidation. Compression occurs instantaneously as a change in water pressure (e. g. , from water table draw down) occurs and the peat matrix is unable to withstand the increased pressures and subsides. Oxidation is the long term chemical breakdown of the peat under aerobic conditions. <br /><br /> Consequently, in 2002 the water table in a fen peatland near Quebec City was lowered by ~20 cm (Experimental site), and the hydrological response was measured compared to a Control (no manipulation) and Drained site (previously drained c. 1994). <br /><br /> As a result of the draw-down, the surface in the Experimental pool decreased 5, 15 and 20 cm in the ridge, lawn and mat topographic locations, respectively resulting in an increased bulk density of ~60% in the Experimental lawn. Hydraulic conductivity (K) generally decreased with depth and from Control (25 to 125 cm) 10<sup>-1</sup> to 10<sup>-5</sup> cm s<sup>-1</sup> to Experimental (25 to 125 cm) 10<sup>-2</sup> to 10<sup>-7</sup> cm s<sup>-1</sup> and to Drained (25 to 75 cm) 10<sup>-2</sup> to 10<sup>-6</sup> cm s<sup>-1</sup>. In similar topographic locations (ridge, lawn, mat), K trended Control>Experimental>Drained, usually by an order of magnitude. <br /><br /> Water table fluctuations in the Drained site were, on average, twice that of the Control site, whereas water table fluctuations within sites trended ridge>lawn>mat. The water table in the Control lawn was able to remain at a stable depth relative to the surface (~ -1 cm) because the lawn peat floats with changes in water table position. However, because of the denser, degraded peat, the Drained lawn peat was more rigid, forcing the water to fluctuate relative to the surface, further enhancing peat decay and densification. <br /><br /> While climatic change will not occur instantaneously the limitations of the experiment required an abrupt change in water table position (drainage). However, regardless of how volume change occurs in the peat (compression or oxidation) the direction of change to the hydraulic properties is the same (increased bulk density, decreased hydraulic conductivity) which affects the hydrology of these systems (increase water table fluctuations and decreases surface movement). Thus, valuable information can be obtained regarding the changing role of peatlands in global biogeochemical cycling processes.
7

The Impact of Governance on Disaster Vulnerability

Steckley, Marylynn January 2006 (has links)
Abstract: This thesis outlines research that was conducted on the relationship between governance, public policy and the impacts of disasters. Here, the vulnerability approach to disaster management is viewed through a political economy perspective, and I contend that political ideologies and economic structures influence vulnerability to disaster. This perspective is taken in order to determine how vulnerability reduction fits into a political agenda that combines a strong central state with a liberal economy. Khao Lak and Koh Phi Phi Don were the most severely impacted of Thailand's coastal communities in the 2004 Indian Ocean tsunami. These two communities are used as primary case studies for the research. The population groups that were most vulnerable to the December 26, 2004 Asian tsunami are identified, and the social, environmental, political and economic factors that contributed to their vulnerability are analyzed. The methods of data collection for this project included interviews with key informants and with residents of Khao Lak and Koh Phi Phi Don. The conclusions drawn from the research fed into a series of recommendations designed to assist in ongoing disaster vulnerability reduction efforts in Thai and other developing country communities.
8

Effect of Hydrological Regimes on Groundwater Phosphorus Transfer in a Riparian Wetland

Zhang, Zheng 11 September 2007 (has links)
Riparian wetlands are important areas for regulating phosphorus (P) transfer in shallow groundwater. Limited knowledge is currently available regarding the effects of hydrological regimes on the transfer process of various P forms in shallow groundwater in upland-riparian-stream continuums in agricultural areas. This study focuses on P transfer in shallow groundwater within and between the riparian zone and hyporheic zone in Spencer Creek, and considers the effects on P transfer caused by flooding from the drawdown of the upstream Valens Reservoir, Hamilton, southern Ontario. A series of piezometer nests (each nest consisted of three piezometers at the depths of 50 cm, 100 cm and 150 cm) and corresponding wells were installed at the upland-riparian interface, riparian corridor and riparian-stream interface along two transects with different vegetation covers. Water chemistry was measured in groundwater and the stream from May 10 to October 20, 2006. The chemistry parameters included total phosphorus (TP), soluble reactive phosphorus (SRP), soil-extractable phosphorus, dissolved oxygen (DO), total dissolved solids (TDS) and pH. Water table elevation, hydraulic head and saturated hydraulic conductivity (Ksat) were measured at each location along the transects. Groundwater TP concentrations at the two transects ranged from 11.8 µg/L to 2685.6 µg/L with an average (mean ± standard error) of 365.2 ± 25.9 µg/L and from 12.7 µg/L to 8485.5 µg/L with an average of 742.4 ± 109.0 µg/L during baseflow and flood conditions, respectively. The groundwater SRP concentrations ranged from 3.6 µg/L to 417.9 µg/L with an average of 44.0 ± 3.8 µgL-1 and from 2.1 µg/L to 280.4 µg/L with an average of 33.9 ± 5.2 µg/L during baseflow and flood conditions, respectively. For both transects, mean TP and SRP concentrations in piezometers tended to increase with increasing distance from the field during both baseflow and flood. This trend was poorly correlated with depth. SRP concentrations in groundwater did not show the same decreasing trend by depth. The flood caused by the drawdown of upstream Valens Reservoir significantly increased TP concentrations (p=0.002) but significantly decreased SRP concentrations (p<0.001) in groundwater in the riparian zone. The TP concentrations at three depths were all significantly lower at transect T1 (predominantly grass cover) than T4 (predominantly forest cover) (50 cm: p=0.001; 100 cm: p<0.001; 150 cm: p<0.001). The SRP concentrations at 50 cm were significantly lower at transect T1 than T4 (p=0.003). The results of this study suggested that hydrology was a dominant factor regulating groundwater P transfer within the upland-riparian-stream continuum while other factors such as vegetation type and substrate characteristics were less important. The effectiveness of riparian zones to reduce P transport in groundwater from agricultural fields to adjacent streams will depend highly on site-specific hydrological regimes.
9

The Regional Integration of Protected Areas: A Study of Canada's National Parks

McCleave, Julia Maggie January 2008 (has links)
The relationship between protected areas and their regions is complex, dynamic, and often based on social interactions. It is widely accepted that protected areas are not “islands” – rather they are connected to their regions through ecological interactions such as the movement of air, water, wildlife, or fire across boundaries; social interactions such as relationships between protected area agency staff and local people; and economic interactions such as the development of on-site and off-site goods and services for protected area visitors. Regional integration is a complex process by which protected area staff and regional actors engage in formal and informal social interactions in order to reach independent and shared goals related to the protected area. Regional integration is influenced by regional contextual factors such as the biophysical environment, the economy, demographics, history, and culture. In order to develop the theory and improve the practice of the regional integration of protected areas, a qualitative study of five national parks in Canada and their regions was undertaken. The case studies were Kejimkujik National Park and National Historic Site, Nova Scotia; Gros Morne National Park, Newfoundland and Labrador; Waterton Lakes National Park, Alberta; and Mount Revelstoke and Glacier National Parks, British Columbia. Semi-structured interviews were conducted with 112 regional actors including Parks Canada staff, provincial government agency staff, local business owners, First Nations, and resource users. Each case study had a unique regional context as well as formal and informal mechanisms in place for interaction and communication between park staff and regional actors. Kejimkujik National Park and National Historic Site was perceived by participants to have very strong links with the scientific community, a developing relationship with First Nations, but weak links with local communities. Gros Morne National Park was perceived by participants to have undergone a significant shift in the way that park staff interact with regional actors and has several unique mechanisms in place for interacting with regional actors. The regional integration of Waterton Lakes National Park was perceived by participants to be stronger due to numerous personal relationships between park staff and key regional actors. The park is also well known for its close working relationship with Glacier National Park, Montana. Mount Revelstoke and Glacier National Parks were perceived by participants as somewhat “in the background” in a region undergoing significant change. There are several long-standing working relationships in place between park staff and regional actors but participants’ perceptions of the parks’ connections with the tourism industry and the local community were varied. Several characteristics of strong regional integration were identified including park staff being aware of the park’s effects on the park region; principles in place for park involvement in regional issues; and regular informal interactions occurring between park staff and regional actors. An assessment was made of the strength of regional integration of the case studies based on the formal and informal mechanisms for communication and interaction in place in the case study regions, their regional contexts, and the presence or absence of the characteristics of strong regional integration. It was found that GMNP has the strongest regional integration of all of the case studies while the regional integration of the three other case studies was strong in some areas and weaker in others. Several suggestions are made for improving the regional integration of national parks in Canada including decreasing the turnover of key park staff; effectively communicating the park mandate to regional actors; improving relationships with First Nations; obtaining political and managerial “buy-in” for regional integration; and increasing informal interactions with regional actors.
10

Dual-polarization (HH/HV) RADARSAT-2 ScanSAR Observations of New, Young and First-year Sea Ice

Casey, John Alexander January 2010 (has links)
Observations of sea ice from space are routinely used to monitor sea ice extent, concentration and type to support human marine activity and climate change studies. In this study, eight dual-polarization (dual-pol) (HH/HV) RADARSAT-2 ScanSAR images acquired over the Gulf of St. Lawrence during the winter of 2009 are analysed to determine what new or improved sea ice information is provided by dual-pol C-band synthetic aperture radar (SAR) data at wide swath widths, relative to single co-pol data. The objective of this study is to assess how dual-pol RADARSAT-2 ScanSAR data might improve operational ice charts and derived sea ice climate data records. In order to evaluate the dual-pol data, ice thickness and surface roughness measurements and optical remote sensing data were compared to backscatter signatures observed in the SAR data. The study found that: i) dual-pol data provide improved separation of ice and open water, particularly at steep incidence angles and high wind speeds; ii) the contrast between new, young and first-year (FY) ice types is reduced in the cross-pol channel; and iii) large areas of heavily deformed ice can reliably be separated from level ice in the dual-pol data, but areas of light and moderately ridged ice cannot be resolved and the thickness of heavily deformed ice cannot be determined. These results are limited to observations of new, young and FY ice types in winter conditions. From an operational perspective, the improved separation of ice and open water will increase the accuracy of ice edge and total ice concentration estimates while reducing the time required to produce image analysis charts. Further work is needed to determine if areas of heavily ridged ice can be separated from areas of heavily rafted ice based on knowledge of ice conditions in the days preceding the formation of high backscatter deformed ice. If rafted and ridged ice can be separated, tactical ridged ice information should be included on image analysis charts. The dual-pol data can also provide small improvements to ice extent and concentration data in derived climate data records. Further analysis of dual-pol RADARSAT-2 ScanSAR data over additional ice regimes and seasons is required.

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