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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.
431

Scaling Nature-based Solutions in Urban Areas: Assessment Methods and Insights for Planning and Design

Orta Ortiz, Maria Susana 21 October 2022 (has links)
Nature-based solutions, through the protection, restoration, management, and creation of new and novel urban ecosystems and the provision of ecosystem services, constitute a promising option for pursuing urban sustainability. Despite the scientific evidence of numerous environmental, social, and economic benefits, pilot projects remain the dominant implementation mechanism of NbS in urban contexts. Considering this, the EU policy and scientific community promote scaling NbS, that is, their systematic integration in urban planning and other decision-making processes to impact more people over a longer time frame. This thesis addresses three main scaling mechanisms that can contribute to mainstream NbS in urban areas: the application of NbS in multiple contexts (scaling out), changes in planning regime (scaling up), and new thinking and values (scaling deep). The first part of the thesis assessed the three scaling mechanisms through a qualitative content analysis of policy and planning documents in a real-life Spanish multilevel planning and governance context. Several scaling patterns were identified, upon which planning characteristics that hinder signs of progress on the scaling out, scaling up, and scaling deep of NbS, as well as opportunities, emerged. The rest of the thesis focused on the key challenges of the scaling-out mechanism. The implementation of multiple NbS was simulated stepwise for the case study of Las Palmas de Gran Canaria, and curves of cumulative impacts were quantified in terms of ES supply and beneficiaries. The non-linear relationships between NbS implementation and impacts served to discuss critical issues for planning NbS scaling-out strategies. The last study of the thesis investigated the design of specific NbS at the local scale for urban stormwater management, considered a determinant issue for ensuring the adaptability and efficiency of scaled-out NbS. A review of the scientific literature identified a broad set of design variables, related impacts on runoff mitigation and stormwater treatment, and assessment indicators. By critically analyzing the relationship between design variables and impacts, the thesis drew some NbS design recommendations for practitioners. The thesis concluded by providing several insights for the NbS planning and design that can facilitate pursuing scaling goals in urban areas. Finally, further research opportunities emerged concerning assessment methods in various urban contexts and how actions across governance levels and sectors, the role of actors’ coalitions, and co-production/co-learning of knowledge can aid in supporting the flourishment of NbS in cities.
432

Assessing Progress toward Sustainability: Development of a Systemic Framework and Reporting Structure

Hodge, Robert A. L. January 1995 (has links)
No description available.
433

Assessing spatial and temporal vegetative dynamics at mentor marsh, 1796 to 2000 A.D

Fineran, Stacey A. January 2003 (has links)
No description available.
434

Soil Respiration During Partial Canopy Senescence in a Northern Mixed Deciduous Forest

Nietz, Jennifer Goedhart 09 September 2010 (has links)
No description available.
435

Soil Respiration Response to Disturbance in a Northern Michigan Forest

Flynn, Conor R. 20 June 2012 (has links)
No description available.
436

INNOVATION, IMITATION, AND IPR STRATEGY IN THE GLOBAL TIRE INDUSTRY

Kim, Jung Kwan, 0000-0001-6371-0622 January 2020 (has links)
This dissertation research aims to illuminate the interdependence of inimitability, competitive landscape, and the factors that bind them. Specifically, this study examines the antecedents and effectiveness of investments in inimitability within a historical context of innovation and competition in a mature sector, the global tire industry. The findings here contribute to our understanding of the complexity of inimitability that works for competitive advantage in light of the dynamics of competition in an industry as the adoption of innovation and intellectual property rights (IPR) protection continues to change. The contribution of this dissertation is two-fold. First, this dissertation highlights the dynamic nature of resource inimitability and protection. Although it is conventionally assumed that firms have strong incentives to protect valuable innovations with weak inimitability, this study shows that weak inimitability of a key resource does not necessarily trigger protection from imitation. Moreover, the link between resource inimitability and imitation protection is not static. When imitating a key resource would destroy the imitator’s other valuable resources, the key resource stays inimitable, and the owner firm of the resource does not engage in active protection. The findings of this study deepen our understanding of why firms choose not to invest in imitation protection and the timing when firms finally decide to deter imitation. This research aims to shift the resource-based view (RBV) toward a more dynamic and practical setting in which firms can delay their investment in inimitability and alter their protection strategy according to a newly emerged competitive landscape. Second, this dissertation reveals the strategic choice of emerging economy firms between innovation and imitation beyond global agreements of IPR protection. Formal IPRs under global agreements are a policy linchpin of the new global knowledge economy. However, while some emerging economy firms have successfully transitioned from imitation to innovation, others persist in imitation, sometimes resulting in IPR violations. To understand the divergent behaviors, this study follows design innovation in the global tire industry, uncovering patterns of IPR violations after the establishment of a global IPR protection standard. The findings show that the presence of “keystone organizations” in a national industry ecosystem matters because these organizations enforce innovation in the ecosystem. This study thus emphasizes the importance of linkages to keystone organizations as crucial elements supporting operations that comply with global IPR regulations. Policymakers are recommended to devise policy instruments to facilitate the growth of keystone organizations and their close alliances with embedded actors to build a critical mass of innovation capability and IP stocks. / Business Administration/Strategic Management
437

Net Ecosystem CO2 Exchange in Natural, Cutover and Partly Restored Peatlands

Warner, Kevin D. 07 1900 (has links)
<p> Peatlands are an important component of the global carbon cycle, storing 23 g C m-2 yr-1 to comprise a global carbon pool of approximately 455 Pg. Peat drainage and harvesting results in removal of surface vegetation, thereby reducing gross photosynthesis to zero. Moreover, lowering the water table increases carbon oxidation. Consequently, peatland drainage and mining can reduce or eliminate the carbon sink function of the peatland. In the first part of this study, net ecosystem CO2 exchange was studied in a natural (NATURAL), two-year (YOUNG) and seven-year (OLD) post cutover peatland near Ste. Marguerite Marie, Quebec during the summer of 1998. Although the NATURAL site was a source of CO2 during the study season, CO2 emissions were 270 to 300% higher in the cutover sites (138, 363, and 399 g CO2-C m-2; NATURAL, YOUNG and OLD, respectively). Active restoration practices and natural re-vegetation of peatlands have the potential to return these ecosystems to net carbon sinks by increasing net ecosystem production (NEP) and therefore decreasing CO2 emissions to the atmosphere. Net ecosystem CO2 exchange in a natural (NATURAL) peatland and a partly restored peatland (REST) near Ste. Marguerite Marie, Quebec, was compared with a naturally re-vegetated peatland (RVEG) near Riviere-du-Loup, Quebec. Ecophysiological parameters indicate that the REST site was more than twice as productive as the natural LAWNS and three times as the RVEG site (GPmax=18.0, 8.3, and 6.5 g CO2 m-2 d-1, respectively). These results indicate that active restoration improves carbon sequestration over natural re-vegetation but that the net carbon sink function at both sites has not been restored. The presence of Sphagnum cover at the RVEG site resulted in a significant decrease in net ecosystem respiration (NER), indicating the potential for decreasing soil respiration at restored cutover sites through increasing the volumetric soil moisture content.</p> / Thesis / Master of Science (MSc)
438

Concepts and methods for integrating environmental justice and Nature-based solutions in cities

Kato Huerta, Jarumi 12 July 2022 (has links)
Over the past decades, the environmental justice movement has developed growing concerns about the unequal distribution of environmental harms and the uneven access to environmental amenities. The movement rapidly became an academic field that has criticised diverse urban sustainability strategies for failing to address environmental justice issues in its three dimensions: recognition, procedure and distribution. Hence, this thesis aims to explore how this concept could be integrated into the planning of Nature-based solutions in cities through advancing conceptual and methodological contributions. Through an extensive revision of academic literature, several setbacks in the inclusion of environmental justice for urban Nature-based solutions are addressed. This information helped operationalise a distributive environmental justice index that could identify intra-urban injustices related to existing and compounding issues such as the overburdening of environmental risk for socially disadvantaged communities and a lack of access to multifunctional green space benefits. Once these injustices are identified, alternative scenarios for implementing Nature-based solutions are assessed by considering relevant urban planning and policy goals. The last part of this thesis focuses on the level of integration of environmental justice in the context of climate change adaptation and mitigation. An extensive review of Urban Climate Action Plans in Latin America reveals that environmental justice concerns are rarely translated into concrete climate actions. Moreover, the transformative potential of Nature-based solutions for ameliorating environmental justice conditions in cities is not fully explored. With these results, potential opportunities and recommendations that could enable environmental justice are discussed, especially highlighting that the integration of diverse social perspectives and realities is integral to the process of giving rise to just and sustainable urban futures.
439

Amphibian Population and Community Characteristics, Habitat Relationships, and First-Year Responses to Clearcutting in a Central Appalachian Industrial Forest

Williams, Lori Ann 08 October 2004 (has links)
The overall goal of this project was to provide baseline data on amphibian species richness, relative abundance, and habitat use for a long-term landscape ecology study on MeadWestvaco industrial forest in the Allegheny Highlands of West Virginia. From results of area-constrained daytime searches (10 m x 10 m plots) across the landscape, I developed 9 regression models to predict amphibian relative abundance. I constructed models for each year for all plots on all habitat types, plots that were in a Stream Management Zone (SMZ), and plots that were in upland, or non-SMZ, habitat. Distance to perennial or ephemeral streams or perennial ponds (SMZ classification), the amount of available rocks along transects, and site index were the 3 most important habitat variables in models for all plots combined and were responsible for 24-32% of the inherent variation in population relative abundance. Other habitat variables that were significant in models were year, % canopy cover, the amount of available woody debris of decomposition classes 3-5 along transects, % woody stems (<7.5 cm DBH), soil pH, and % herbaceous vegetation. R2PRESS values for all 9 models ranged from 0.08 to 0.35. Amphibian relative abundance showed positive relationships with all significant habitat variables with the exception of year and % woody stems. In natural cover object use/availability analyses, I discovered salamanders preferred rocks over woody debris, relative to the amount available of each. Salamanders preferred flat rocks to any other shape, flagstones to any other type of rock, and rock lengths in the 31-40 cm class. Preferred wood widths were in class 5-10 cm, while preferred wood lengths were in class <50 cm; salamanders exhibited strong preferences for wood in higher states of decomposition (class 3-5). I provided baseline, preharvest data for 28-acre reference areas on 9 forest compartments scheduled for clearcuts. I sampled all 9 reference areas preharvest and sampled 3 during year 1 postharvest using coverboard and night plot surveys. On these 3 areas, species richness declined from preharvest to postharvest, but species diversity showed little change. Overall relative abundance declined significantly preharvest to postharvest with coverboard sampling (p=0.0172) and night plot sampling (p=0.0113). At coverboard stations, relative abundance declined significantly from preharvest to postharvest at a distance of 5-10 m (p=0.0163) and 40-50 m (p=0.0193) away from adjacent mature forest. Finally, using Pianka's index, I compared the night plot and coverboard sampling techniques in terms of proportions of the 4 most common species captured. These sampling techniques on average were >80% similar for all reference areas. / Master of Science
440

Eco-hydro-morphodynamics and ecosystem services of near-natural river corridors

Crivellaro, Marta 24 April 2024 (has links)
Near-natural river corridors (NNRs) provide crucial habitat for a host of biota and support the survival of people and nature worldwide at multiple spatiotemporal scales. Furthermore, NNRs represent fundamental references for river conservation, management, and restration, offering the opportunity to investigate processes under minimal anthropic disturbances. However, in the Anthropocene large near-natural rivers are rare gems in Europe an worldwide, and knowledge of their dynamics and ecosystem services are often scarcedue to a lack of hydromorphological and ecological data, monitoring, and baseline studies. Despite the scarcity and fragmentation of pertinent studies, many national and international guidelines and directives point to NNRs as reference systems for conservation, management, and restoration targets. In this framework, this Ph.D. thesis investigates the value of NNRs in the Anthropocene with an interdisciplinary approach, bridging fluvial geomorphology and environmental planning disciplines to support freshwater management and conservation in international cooperation for development. The first part of the research activity is rooted in fluvial geomorphology and explores the spatiotemporal trajectories of NNRs adopting several remote sensing products, cloud computing, and geomatic. The recent morphological trajectory of the near-natural Vjosa River (GR/AL) is presented as the response of the river to multidecadal climatic oscillations and more recent localized anthropic pressures, warning about the importance of considering and quantifying the geomorphic sensitivity of river systems in management and conservation. Thus, we focused on framing remote sensing-based procedures for characterizing active river channel spatiotemporal dynamics in the Mediterranean biogeoclimatic region. The second part of the research activity deals with the need to improve riverscape science and landscape management dialogue and the valuation of river ecosystem services. Focusing on inland waters ecosystem services, we integrate a socio-cultural approach with spatial analysis for cultural ecosystem services supply assessment in selected Albanian Protected freshwater ecosystems, outlining the relevant role of ecotones in providing cultural ecosystem services and the multifacet value of such dynamic zones. The third part of the research activity strongly links fluvial geomorphology and environmental management and conservation. It proposes the reconstruction of in-channel vegetation age and related ecosystem services spatiotemporal trajectories in targeted reaches of the Vjosa (GR/AL) and Tagliamento (IT) NNRs, integrating cloud computing, multispectral images, and fieldwork data. Developed baseline knowledge and tools can support the study, management, and conservation of highly dynamic river corridors in Mediterranean temperate climates, and the proposed integrated and multidisciplinary set of approaches is promising to cope with data scarcity that often characterizes the few remaining near-natural rivers in the world.

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