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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.
601

Survivable hierarchical optical path networks employing waveband and wavelength path protection

Yamada, Y., Hasegawa, H., Sato, K. 22 March 2009 (has links)
No description available.
602

Regeneration, Quarterization and Historic Preservation in Urban Sweden : Norrköping, 1970-2010

Legnér, Mattias January 2009 (has links)
No description available.
603

Remedial agriculture: Reconciling ecological restoration and agriculture in the design of a wetland complex

Rehbein, Christina January 2004 (has links)
Reconciling human landscapes with wildlife needs can demand innovative solutions. Enhancing wildlife conservation in agricultural landscapes requires habitat restoration; returning marginal farmlands to wetlands in a way that remains productive for farmers can aid existing strategies. This study develops and explores the feasibility of an ecological design to rehabilitate wet, poor quality farmland into a wetland that can serve as wildlife habitat while producing a crop. Research targets methods of biophysical site restoration that are feasible for farmers to initiate; identification of temperate wetland crops with potential to meet economic and ecological criteria; and parameters for meeting farmers' needs in terms of management and desirability. Scientific literature on wetland and restoration ecology is examined and integrated with agricultural studies and interview responses from landowners involved in alternative food production. Primary data collection for design development centers on coastal British Columbia, where competing land uses have degraded many former wetlands while the region's fertile soils support prolific, diversified farming. Qualitative, semi-structured interviews with key informants involved in local food production were conducted as part of a participative research process in order to get input and feedback throughout design development. A case study site was chosen in a seasonally flooded agricultural watershed outside of Duncan, B. C. A design is proposed that combines five habitat types with a naturalized cropping system. Major findings include the potential use of many wild and native plants as crops, as a way to provide sufficient economic returns and maintain ecological sustainability. Current opportunities for wetland agriculture include niche marketing, added value products, agrotourism, and increasing sales through farm reputation. Possible deterrents include product marketing, and the unfamiliarity of the plants from a farming perspective, where levels of acceptable damage imposed by fluctuating water conditions, weed competition, and herbivory are undetermined. Participant response was positive overall with regards to the design and preliminary results indicate that such a system could be feasible. Public interest and technical ability to create an agricultural wetland exist; developing creative marketing for such products in North America appears to be the primary challenge. The design is thus proposed as a long-term study to minimize risk for interested landowners. Redesigning human landscapes to include wild species is an important step towards a more sustainable society.
604

An assessment of early-stage forest restoration outcomes and the instruments used to evaluate ecosystem recovery

Lefler, Leah January 2006 (has links)
Ecological restoration projects are considered successful when identified goals are achieved and the ecosystem progresses along a predicted successional trajectory. My study examined the progress of early-stage forest restoration projects within the Regional Municipality of Waterloo to determine the variables that affect early successional trajectories. The study was undertaken to gain further insight into the most appropriate methods to use in the evaluation of restoration outcomes and to provide some useful recommendations for restoration ecologists and practitioners. <br /><br /> Between April-October 2005 and April 2006, data were collected using a stratified random sampling technique and the wandering-quarter method to evaluate herbaceous vegetation, regenerating woody vegetation and mature trees at 7 forest restoration sites within the Regional Municipality of Waterloo. The Regional Municipality of Waterloo was selected as the study area because it has restoration projects established in forested ecosystems and the Region is typical of southern Ontario, i. e. , forest ecosystems have been disturbed by urban and agricultural activities and require ecological restoration. <br /><br /> A nested Analysis of Variance was used to test the responses of various herbaceous and woody vegetation parameters to the restoration site, restoration technique nested within the restoration site, and transects nested within the restoration technique. Site location, restoration technique, and restoration transect all appear to significantly affect restoration progress for some structural metrics. Species diversity (measured by the Shannon-Wiener Index) was significantly affected by the restoration site (p<0. 01) and transect nested within the restoration technique (p<0. 01). For some sites, differences in diversity among transects are expected to diminish as restoration proceeds and natural succession progresses. For heavily degraded sites, however, that exhibit low native plant species diversity may require a more intensive restoration strategy to improve local conditions. Density was significantly affected by the restoration site (p<0. 001) and the restoration technique nested within the site (p<0. 01). Sites without a closed forest canopy had higher densities of plants for all sampling guilds. The percentage of native species was significantly affected by the restoration site (p<0. 01) and the restoration technique nested with the site (p<0. 05). Sites that were restored from degraded forest conditions, rather than from old fields, exhibited significantly higher percentages of native plants for all sampling guilds. <br /><br /> Generally, sites with high species diversity, a high percentage of native species, and high density indicated that ecological restoration was progressing on the predicted successional trajectories and should lead to a successful restoration as time goes on. Results indicate that 4 out of 7 restoration sites are progressing as expected, i. e. , towards the predetermined restoration goal. The remaining 3 restoration sites may recover over time, but will most likely require additional restoration measures to achieve a desirable long-term outcome. At early-stages, structural measures appear to be useful indicators for evaluating the progress of restoration. In order for a restoring ecosystem to follow along an expected trajectory, formative evaluation must occur throughout the process to ensure that positive outcomes are achieved along the way. The study concludes that evaluating the progress of forest restoration projects at an early stage could greatly improve the long-term success of restoration outcomes by offering opportunities for mid-course correction and to learn from past mistakes.
605

Sustainable Foodscapes: Obtaining Food within Resilient Communities

King, Meaghan January 2009 (has links)
This thesis examines the feasibility of fostering “sustainable foodscapes” in urban communities. A review of the literature on the topics of sustainability, resilience, sustainable food security, and healthy communities is used to determine to the definition of “sustainable foodscapes.” This thesis uses a framework of socio-ecological restoration to consider how communities might adopt sustainable foodscapes. A case study is conducted in the city of Waterloo, Ontario to test the criteria of sustainable foodscapes and explore some of the practical opportunities and barriers to developing sustainable foodscapes in an urban community. The methods for the case study include semi-structured interviews. Interview results indicate that a variety of sustainable foodscapes such as community gardening, individual gardening, and foraging are used in Waterloo already, and survey results suggest that various members of the community are open to the adoption of these foodscapes. The case study results reveal that diverse community members view sustainable foodscapes as an important contribution to community health, less for the purpose of ecological sustainability than for their usefulness as a way of promoting community interaction, social learning, and fostering a sense of place. Ways to conduct a socio-ecological restoration for sustainable foodscapes in Waterloo could include increasing areas for the purposes of foraging to occur in an ecologically benign manner, such as on marginal or private land; creating municipal policies and Official Plans that provide support for community gardens, and fostering more accepting attitudes towards sustainable foodscapes by providing increased opportunities for education and participation among community members.
606

Remedial agriculture: Reconciling ecological restoration and agriculture in the design of a wetland complex

Rehbein, Christina January 2004 (has links)
Reconciling human landscapes with wildlife needs can demand innovative solutions. Enhancing wildlife conservation in agricultural landscapes requires habitat restoration; returning marginal farmlands to wetlands in a way that remains productive for farmers can aid existing strategies. This study develops and explores the feasibility of an ecological design to rehabilitate wet, poor quality farmland into a wetland that can serve as wildlife habitat while producing a crop. Research targets methods of biophysical site restoration that are feasible for farmers to initiate; identification of temperate wetland crops with potential to meet economic and ecological criteria; and parameters for meeting farmers' needs in terms of management and desirability. Scientific literature on wetland and restoration ecology is examined and integrated with agricultural studies and interview responses from landowners involved in alternative food production. Primary data collection for design development centers on coastal British Columbia, where competing land uses have degraded many former wetlands while the region's fertile soils support prolific, diversified farming. Qualitative, semi-structured interviews with key informants involved in local food production were conducted as part of a participative research process in order to get input and feedback throughout design development. A case study site was chosen in a seasonally flooded agricultural watershed outside of Duncan, B. C. A design is proposed that combines five habitat types with a naturalized cropping system. Major findings include the potential use of many wild and native plants as crops, as a way to provide sufficient economic returns and maintain ecological sustainability. Current opportunities for wetland agriculture include niche marketing, added value products, agrotourism, and increasing sales through farm reputation. Possible deterrents include product marketing, and the unfamiliarity of the plants from a farming perspective, where levels of acceptable damage imposed by fluctuating water conditions, weed competition, and herbivory are undetermined. Participant response was positive overall with regards to the design and preliminary results indicate that such a system could be feasible. Public interest and technical ability to create an agricultural wetland exist; developing creative marketing for such products in North America appears to be the primary challenge. The design is thus proposed as a long-term study to minimize risk for interested landowners. Redesigning human landscapes to include wild species is an important step towards a more sustainable society.
607

An assessment of early-stage forest restoration outcomes and the instruments used to evaluate ecosystem recovery

Lefler, Leah January 2006 (has links)
Ecological restoration projects are considered successful when identified goals are achieved and the ecosystem progresses along a predicted successional trajectory. My study examined the progress of early-stage forest restoration projects within the Regional Municipality of Waterloo to determine the variables that affect early successional trajectories. The study was undertaken to gain further insight into the most appropriate methods to use in the evaluation of restoration outcomes and to provide some useful recommendations for restoration ecologists and practitioners. <br /><br /> Between April-October 2005 and April 2006, data were collected using a stratified random sampling technique and the wandering-quarter method to evaluate herbaceous vegetation, regenerating woody vegetation and mature trees at 7 forest restoration sites within the Regional Municipality of Waterloo. The Regional Municipality of Waterloo was selected as the study area because it has restoration projects established in forested ecosystems and the Region is typical of southern Ontario, i. e. , forest ecosystems have been disturbed by urban and agricultural activities and require ecological restoration. <br /><br /> A nested Analysis of Variance was used to test the responses of various herbaceous and woody vegetation parameters to the restoration site, restoration technique nested within the restoration site, and transects nested within the restoration technique. Site location, restoration technique, and restoration transect all appear to significantly affect restoration progress for some structural metrics. Species diversity (measured by the Shannon-Wiener Index) was significantly affected by the restoration site (p<0. 01) and transect nested within the restoration technique (p<0. 01). For some sites, differences in diversity among transects are expected to diminish as restoration proceeds and natural succession progresses. For heavily degraded sites, however, that exhibit low native plant species diversity may require a more intensive restoration strategy to improve local conditions. Density was significantly affected by the restoration site (p<0. 001) and the restoration technique nested within the site (p<0. 01). Sites without a closed forest canopy had higher densities of plants for all sampling guilds. The percentage of native species was significantly affected by the restoration site (p<0. 01) and the restoration technique nested with the site (p<0. 05). Sites that were restored from degraded forest conditions, rather than from old fields, exhibited significantly higher percentages of native plants for all sampling guilds. <br /><br /> Generally, sites with high species diversity, a high percentage of native species, and high density indicated that ecological restoration was progressing on the predicted successional trajectories and should lead to a successful restoration as time goes on. Results indicate that 4 out of 7 restoration sites are progressing as expected, i. e. , towards the predetermined restoration goal. The remaining 3 restoration sites may recover over time, but will most likely require additional restoration measures to achieve a desirable long-term outcome. At early-stages, structural measures appear to be useful indicators for evaluating the progress of restoration. In order for a restoring ecosystem to follow along an expected trajectory, formative evaluation must occur throughout the process to ensure that positive outcomes are achieved along the way. The study concludes that evaluating the progress of forest restoration projects at an early stage could greatly improve the long-term success of restoration outcomes by offering opportunities for mid-course correction and to learn from past mistakes.
608

Sustainable Foodscapes: Obtaining Food within Resilient Communities

King, Meaghan January 2009 (has links)
This thesis examines the feasibility of fostering “sustainable foodscapes” in urban communities. A review of the literature on the topics of sustainability, resilience, sustainable food security, and healthy communities is used to determine to the definition of “sustainable foodscapes.” This thesis uses a framework of socio-ecological restoration to consider how communities might adopt sustainable foodscapes. A case study is conducted in the city of Waterloo, Ontario to test the criteria of sustainable foodscapes and explore some of the practical opportunities and barriers to developing sustainable foodscapes in an urban community. The methods for the case study include semi-structured interviews. Interview results indicate that a variety of sustainable foodscapes such as community gardening, individual gardening, and foraging are used in Waterloo already, and survey results suggest that various members of the community are open to the adoption of these foodscapes. The case study results reveal that diverse community members view sustainable foodscapes as an important contribution to community health, less for the purpose of ecological sustainability than for their usefulness as a way of promoting community interaction, social learning, and fostering a sense of place. Ways to conduct a socio-ecological restoration for sustainable foodscapes in Waterloo could include increasing areas for the purposes of foraging to occur in an ecologically benign manner, such as on marginal or private land; creating municipal policies and Official Plans that provide support for community gardens, and fostering more accepting attitudes towards sustainable foodscapes by providing increased opportunities for education and participation among community members.
609

The Early Post-restoration Population Dynamics and Community Interactions of a Former Agricultural Field in the Carolinian Canada Life Zone

Inlow, Katelyn J. January 2010 (has links)
Monitoring ecological restoration at the community scale provides insight into how the population dynamics and community interactions are progressing through time in comparison to a restoration’s goals and reference conditions. This study monitored the early post-restoration dynamics of a sand plain located in the Carolinian Canada ecozone called Lake Erie Farms. The restoration consisted of restoring three habitats via sculptured seeding: a mesic forest, oak woodland, and sand barren. The hypothesis of this study is that the restoration efforts have established population dynamics and community interactions consistent with successional patterns expected from comparative literature. Community ecology, directed succession, and alternative stable states are the underlying theories that provided a conceptual and theoretical lens from which to study the objectives and hypothesis. To gain insight into the community dynamics at Lake Erie Farms the vegetation abundance, seed abundance and viability of the seedbank, seed viability of the 6 most dominant species (3 most dominant native species & 3 most dominant weedy species), and soil moisture & pH were monitored. The analysis was conducted using a RMANOVA of a nested design (P > 0.001, 0.01 and 0.05) to compare the variables in relation to the site (i.e. the sum of all the quadrats), the restoration treatment nested within the site, the field nested within the site, the transect nested within the restoration treatment and the quadrat nested within the restoration treatment. The significant findings of this study include: i) the restoration treatments are producing similar results as those expected from the literature, though there is evidence of the sculptured seeding treatment accelerating the successional stage at Lake Erie Farms compared to abandoned agricultural fields in similar ecosystems because of the presence of later-successional species; ii) the control areas are less diverse than each of the restoration units (P>0.05); and iii) the soil moisture among the treatments is beginning to diverge into the desired restoration units.
610

Två år efter restaurering:Vad har förändrats i bottenfaunan?

Andersson, Klas January 2010 (has links)
The aim of the study was to examine if the benthos in a restored portion of a small lowland stream south of Linkoping differed from two non restored reference areas two years after restoration. The reference areas were one stretch downstream and one upstream stretches of the restored stream. The benthic invertebrates were collected using standardized kick sampling. In order to classify the communities and estimate any differences, three different indices were exercised. In addition rank-abundance curves and checklists were used to get a picture of species composition. The only index that showed a difference between areas was the Berger-Parker diversity index showing that the downstream reference stretch differed from the other two. None of the analyses showed that the restored area was different from the other two, probably due to too short a time since the restoration. To allow for the bottom substrate to develop and stabilize so that species can re-colonize the area.

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