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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.
191

Developing a scenario-based coral reef ecosystem model to assist management following mass coral mortality events

Glen Holmes Unknown Date (has links)
Coral reefs are experiencing increasing levels of stress due to climate change, overfishing, coastal development and nutrient runoff from agriculture to name a few. They are however, economically vital ecosystems in terms of both their income generating capacity and as a source of food for millions of people around the world. This predicament emphasises the need for effective ecosystem management to be able to balance the benefits of coral reefs with the inherent stressors associated with people utilising their resources. It is particularly important given the potential large scale impacts associated with climate change such as mass coral bleaching events. Similarly, much of the need for direct management of coral reefs exists in developing countries where the resources, information, and technology are limited or unavailable for such a task. This places them, in particular, at the high end of management uncertainty and impact vulnerability. Accordingly, there is a pronounced need to improve this capacity to understand coral reef ecosystem function and to use this to better predict the overall systems level outcome of management options. This thesis has sought to improve our understanding of key ecological elements of coral reef ecosystems and to build on this new knowledge to produce a widely applicable ecosystem model that will allow managers to better understand and predict the outcomes of their actions. Coral reef ecosystem behaviour is far from understood in its entirety and there are many facets that require detailed further investigations to be able to more confidently predict ecosystem response to any given disturbance. To enhance the current understanding of coral reef ecosystems prior to the model development, investigations were undertaken into the dynamics of nitrogen on a coral reef following bleaching induced coral mortality. The results showed that the rates of nitrogen fixation on surfaces made available due to a coral mortality event increased dramatically in the three months following coral mortality, potentially acting as a driving force for the ecosystem to pass through a phase shift to algal dominance. Application of these nitrogen dynamics to entire coral reef ecosystems required a methodology for scaling these sub coral colony processes to entire reefs. This scaling issue is particularly pertinent given the improved understanding of the overwhelming significance of micro-scale processes to community dynamics. The surface index (SI) concept, relating the two-dimensional projected area to the three-dimensional area of corals was refined and developed for variations of gross coral morphologies. This allowed for the scaling of nitrogen flux estimates to be made over entire reef systems, enabling the incorporation of these fluxes into an ecosystem scale model. One of the key factors associated with the potential for a coral reef to recover from a mass coral mortality event is the potential for new corals to successfully recruit. The process of coral recovery could potentially be enhanced if recruitment is viable in the immediate aftermath of a mortality event. Although investigations in this area were inconclusive, extensive herbivore action on turf assemblages up to eight months old indicated that recruitment may be inhibited through the high palatability of turf assemblages in this age bracket. Integrating these processes with the many other published dynamics of coral reefs allowed for the development of the dynamic systems model. By constraining the model structure to known relationships between the modelling parameters, the model can be calibrated to replicate the dynamics of any coral reef ecosystem. This allows the model to be applied to systems where limited data and/or resources are available, making it widely implementable in developing countries such as the small island states scattered around the tropics. The model is ideally suited to the adaptive management framework whereby managers can continually assess the potential future outcomes of management interventions. In addition, due to the spatially inexplicit and generic nature of the model, it can be easily adapted and integrated into large scale regional modelling frameworks or combined with other modelling packages such as socio-economic or fisheries models to provide enhanced management packages. The culmination of the targeted research and integration of existing knowledge has allowed for the development of an ecosystem model for coral reefs that can be easily adopted by coral reef managers throughout the world. It is however, by no means a definitive coral reef ecosystem model and there are many facets that can and should continue to be refined to enhance the reliability of the model.
192

Developing a scenario-based coral reef ecosystem model to assist management following mass coral mortality events

Glen Holmes Unknown Date (has links)
Coral reefs are experiencing increasing levels of stress due to climate change, overfishing, coastal development and nutrient runoff from agriculture to name a few. They are however, economically vital ecosystems in terms of both their income generating capacity and as a source of food for millions of people around the world. This predicament emphasises the need for effective ecosystem management to be able to balance the benefits of coral reefs with the inherent stressors associated with people utilising their resources. It is particularly important given the potential large scale impacts associated with climate change such as mass coral bleaching events. Similarly, much of the need for direct management of coral reefs exists in developing countries where the resources, information, and technology are limited or unavailable for such a task. This places them, in particular, at the high end of management uncertainty and impact vulnerability. Accordingly, there is a pronounced need to improve this capacity to understand coral reef ecosystem function and to use this to better predict the overall systems level outcome of management options. This thesis has sought to improve our understanding of key ecological elements of coral reef ecosystems and to build on this new knowledge to produce a widely applicable ecosystem model that will allow managers to better understand and predict the outcomes of their actions. Coral reef ecosystem behaviour is far from understood in its entirety and there are many facets that require detailed further investigations to be able to more confidently predict ecosystem response to any given disturbance. To enhance the current understanding of coral reef ecosystems prior to the model development, investigations were undertaken into the dynamics of nitrogen on a coral reef following bleaching induced coral mortality. The results showed that the rates of nitrogen fixation on surfaces made available due to a coral mortality event increased dramatically in the three months following coral mortality, potentially acting as a driving force for the ecosystem to pass through a phase shift to algal dominance. Application of these nitrogen dynamics to entire coral reef ecosystems required a methodology for scaling these sub coral colony processes to entire reefs. This scaling issue is particularly pertinent given the improved understanding of the overwhelming significance of micro-scale processes to community dynamics. The surface index (SI) concept, relating the two-dimensional projected area to the three-dimensional area of corals was refined and developed for variations of gross coral morphologies. This allowed for the scaling of nitrogen flux estimates to be made over entire reef systems, enabling the incorporation of these fluxes into an ecosystem scale model. One of the key factors associated with the potential for a coral reef to recover from a mass coral mortality event is the potential for new corals to successfully recruit. The process of coral recovery could potentially be enhanced if recruitment is viable in the immediate aftermath of a mortality event. Although investigations in this area were inconclusive, extensive herbivore action on turf assemblages up to eight months old indicated that recruitment may be inhibited through the high palatability of turf assemblages in this age bracket. Integrating these processes with the many other published dynamics of coral reefs allowed for the development of the dynamic systems model. By constraining the model structure to known relationships between the modelling parameters, the model can be calibrated to replicate the dynamics of any coral reef ecosystem. This allows the model to be applied to systems where limited data and/or resources are available, making it widely implementable in developing countries such as the small island states scattered around the tropics. The model is ideally suited to the adaptive management framework whereby managers can continually assess the potential future outcomes of management interventions. In addition, due to the spatially inexplicit and generic nature of the model, it can be easily adapted and integrated into large scale regional modelling frameworks or combined with other modelling packages such as socio-economic or fisheries models to provide enhanced management packages. The culmination of the targeted research and integration of existing knowledge has allowed for the development of an ecosystem model for coral reefs that can be easily adopted by coral reef managers throughout the world. It is however, by no means a definitive coral reef ecosystem model and there are many facets that can and should continue to be refined to enhance the reliability of the model.
193

Developing a scenario-based coral reef ecosystem model to assist management following mass coral mortality events

Glen Holmes Unknown Date (has links)
Coral reefs are experiencing increasing levels of stress due to climate change, overfishing, coastal development and nutrient runoff from agriculture to name a few. They are however, economically vital ecosystems in terms of both their income generating capacity and as a source of food for millions of people around the world. This predicament emphasises the need for effective ecosystem management to be able to balance the benefits of coral reefs with the inherent stressors associated with people utilising their resources. It is particularly important given the potential large scale impacts associated with climate change such as mass coral bleaching events. Similarly, much of the need for direct management of coral reefs exists in developing countries where the resources, information, and technology are limited or unavailable for such a task. This places them, in particular, at the high end of management uncertainty and impact vulnerability. Accordingly, there is a pronounced need to improve this capacity to understand coral reef ecosystem function and to use this to better predict the overall systems level outcome of management options. This thesis has sought to improve our understanding of key ecological elements of coral reef ecosystems and to build on this new knowledge to produce a widely applicable ecosystem model that will allow managers to better understand and predict the outcomes of their actions. Coral reef ecosystem behaviour is far from understood in its entirety and there are many facets that require detailed further investigations to be able to more confidently predict ecosystem response to any given disturbance. To enhance the current understanding of coral reef ecosystems prior to the model development, investigations were undertaken into the dynamics of nitrogen on a coral reef following bleaching induced coral mortality. The results showed that the rates of nitrogen fixation on surfaces made available due to a coral mortality event increased dramatically in the three months following coral mortality, potentially acting as a driving force for the ecosystem to pass through a phase shift to algal dominance. Application of these nitrogen dynamics to entire coral reef ecosystems required a methodology for scaling these sub coral colony processes to entire reefs. This scaling issue is particularly pertinent given the improved understanding of the overwhelming significance of micro-scale processes to community dynamics. The surface index (SI) concept, relating the two-dimensional projected area to the three-dimensional area of corals was refined and developed for variations of gross coral morphologies. This allowed for the scaling of nitrogen flux estimates to be made over entire reef systems, enabling the incorporation of these fluxes into an ecosystem scale model. One of the key factors associated with the potential for a coral reef to recover from a mass coral mortality event is the potential for new corals to successfully recruit. The process of coral recovery could potentially be enhanced if recruitment is viable in the immediate aftermath of a mortality event. Although investigations in this area were inconclusive, extensive herbivore action on turf assemblages up to eight months old indicated that recruitment may be inhibited through the high palatability of turf assemblages in this age bracket. Integrating these processes with the many other published dynamics of coral reefs allowed for the development of the dynamic systems model. By constraining the model structure to known relationships between the modelling parameters, the model can be calibrated to replicate the dynamics of any coral reef ecosystem. This allows the model to be applied to systems where limited data and/or resources are available, making it widely implementable in developing countries such as the small island states scattered around the tropics. The model is ideally suited to the adaptive management framework whereby managers can continually assess the potential future outcomes of management interventions. In addition, due to the spatially inexplicit and generic nature of the model, it can be easily adapted and integrated into large scale regional modelling frameworks or combined with other modelling packages such as socio-economic or fisheries models to provide enhanced management packages. The culmination of the targeted research and integration of existing knowledge has allowed for the development of an ecosystem model for coral reefs that can be easily adopted by coral reef managers throughout the world. It is however, by no means a definitive coral reef ecosystem model and there are many facets that can and should continue to be refined to enhance the reliability of the model.
194

Legacies of forest management and fire in mixed-pine forest ecosystems of the Seney National Wildlife Refuge, eastern Upper Michigan

Rist, Stephen George. January 2008 (has links)
Thesis (M.S.)--Ohio State University, 2008. / Title from first page of PDF file. Includes bibliographical references (p. 74-79).
195

Examining effectiveness of Oregon's forest practice rules for maintaining warm-season maximum stream temperature patterns in the Oregon Coast Range /

Fleuret, Jennifer Marie. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2007. / Printout. Includes bibliographical references (leaves 102-110). Also available on the World Wide Web.
196

Exploring the potential of cultural ecosystem services in social impact assessment of Finnish mining projects : Assessment of local cultural values in the municipality of Kolari in Finnish Lapland

Knuuttila, Jussi January 2018 (has links)
Large-scale mining modifies the existing physical environment and has multiple long-term impacts on landscape but also on communities, and their cultural values. In Finland, social impact assessment has become a customary practice in assessing and estimating mining impacts that cause changes to the well-being of individual people and their livelihoods. However, the assessment is often lacking notions of social dimensions of the environment, neglecting discussing aspects such as localities and subjective well-being. Recent studies have highlighted the importance of considering the cultural benefits of the environment to human well-being in environmental decision-making. The purpose of this study is to explore and illustrate how cultural ecosystem services could contribute to the current practice in social impact assessments in Finnish mining projects by highlighting the relation between local people and environment through the valuation of cultural services. The study used a conceptual framework approach of cultural ecosystem services and conducted eight qualitative semi-structured interviews in two villages in Finnish Fell Lapland. The aim was to explore how the local people themselves describe their non-material benefits from the environment. Six out of the eight interviews were conducted walking with the participants. The interviews were recorded and later transcribed for analysis against the conceptual cultural ecosystem services framework. The results show how the well-being of local people was strongly linked to cultural benefits such as sense of place, enabled by meaningful activities in places that were often happening in mundane everyday places. The study implies the importance of considering cultural ecosystem services such as sense of place in the current social impact assessment practice as they help unveiling connections between people, the natural environment and subjective well-being.
197

The potential of ecosystem services as an approach for marine stakeholder engagement

Friedrich, Laura A. January 2017 (has links)
With growing human pressures on the oceans and seas, the resulting decline of ecosystem health and biodiversity is increasingly limiting the ability of marine ecosystems to provide essential functions and resources for human wellbeing. To prevent further marine degradation, an ecosystem based approach to marine management is needed. An integral part of this is constructive stakeholder engagement. However, in a marine context, engagement is often difficult due to traditionally sectoral management and the complexity of marine issues. This thesis presents an interdisciplinary study that evaluates the potential of the ecosystem services approach to support and improve marine stakeholder engagement. First, opportunities and challenges of using the approach in participatory marine management processes were explored through interviews with 39 stakeholders who participated in the application of ecosystem service assessment to marine management in six French and UK case studies. The interviews revealed that the ecosystem services approach can facilitate participatory engagement by improving understanding of complex ecological-socioeconomic systems and fostering constructive dialogue. Second, the potential of the approach for communicating marine management decisions to marine users was tested with a scenario based survey. Responses to three versions of the survey, two with and one without ecosystem services content, were compared, showing that the ecosystem services information did not increase agreement with the management measures proposed in the scenario. An evaluation of the results in the context of environmental behaviour research suggests that the novelty and complexity of the ecosystem services approach might limit its usefulness for top down communication. In contrast, if the approach is integrated in participatory processes, it was concluded that this could have multiple benefits for ecosystem based marine management. From these findings, a conceptual model was developed that provides a normative framework for the effective use of the ecosystem services approach to support constructive participatory engagement in marine governance.
198

The role of Big Data in the evolution of Platform based Ecosystems : A case study of an emerging platform-based ecosystem in the software engineering industry

Kostis, Angelos January 2016 (has links)
Platform based ecosystems are becoming dominant models in the software engineering industry. ‘Big data’ has recently gained increased attention from both academia and practitioners and it is believed that big data affects every sector and industry. While an abundance of research focuses on big data and platform-based ecosystems, these two are typically approached as secluded spheres. This study aimed toward an investigation of big data’s role in the evolution of platform-based ecosystems in the software engineering industry. In the present thesis the influence of big data on the software engineering industry and more specifically, the impact of big data on the evolution of software ecosystems, is examined. A case study focused on a platform owner and pioneer in the software engineering industry has been conducted. This study identifies challenges and opportunities triggered by the advent of big data in context of platform-based ecosystems. Hence, considerable insight regarding the impact of big data on contemporary platform providers and the evolution of platform-centric ecosystems is gained. The findings illustrate that software ecosystems are affected by big data in a positive manner, but some identified challenges emerge and have to be tackled. Additionally, in this paper, it is suggested that both academia and practitioners should dig deeper into this relationship and identify how the evolution of platform-based ecosystems is impacted by the advent of big data.
199

Exploring business models in ecosystemic contexts

Iivari, M. (Marika) 31 May 2016 (has links)
Abstract The purpose of this study is to explore the emergence of ecosystemic business models. Ecosystemic thinking has surfaced as a concept to explain the complexity and interconnected nature of modern business. It reflects a fundamental change in the way we view innovations in particular. Innovations are no longer considered to rise within organizational boundaries alone. Modern business is characterized by a diversity of innovation stakeholders from private and public backgrounds, from large organizations to users and citizens. To further the understanding on the research phenomenon of ecosystemic business models, this study relies on two streams of research: Open innovation and business model research. These fields of academic literature mirror well the paradigmatic shift on how the dynamism and change of modern, interconnected business context impacts innovations, value creation and capture and subsequent competitive advantage. The empirical part of this study has been conducted as qualitative case studies. Also conceptual frameworks have been based on empirical data. Drawing from ecosystem analogy, this study investigates different types of ecosystemic contexts, namely that of business ecosystems and innovation ecosystems, in order to determine not only how and why business models emerge, but also how they develop and transform in such a context. An ecosystemic view on business models emphasizes that value co-creation and co-capture need to be steered by a common motive based on mutually connected opportunities and collective value proposition. This research finds that in a complex, multileveled configuration of ecosystems, striving for synergy within the ecosystem is a prerequisite for successful building of ecosystemic value and competitive advantage as a whole. The results of the study indicate that business models are valid not only at organizational level but at the ecosystemic level as well, as ecosystem synergy and successful orchestration can be achieved through utilizing the ecosystemic business model. / Tiivistelmä Tässä tutkimuksessa esitellään ekosysteemisten liiketoimintamallien käsite ja tarkastellaan ekosysteemisten liiketoimintamallien syntyä. Liiketoimintakontekstin monimutkaisuutta ja monitahoisuutta selitetään yhä useammin ekosysteemisen ajattelun avulla. Innovaatioiden ei nähdä syntyvän enää vain yritysten rajojen sisällä, vaan moderniin liiketoimintakontekstiin kuuluu monia eri sidosryhmiä yksityisistä julkisiin toimijoihin, suuryrityksistä yksittäisiin kuluttajiin ja kansalaisiin. Lisätäkseen ymmärrystä ekosysteemisistä liiketoimintamalleista, tämä tutkimus nojaa kahteen tutkimusalueeseen; avoimeen innovaatioon ja liiketoimintamalleihin. Näiden tutkimusnäkökulmien katsotaan peilaavan hyvin modernin liiketoimintakontekstin dynamiikkaa, muutosta ja näiden vaikutusta innovaatioihin, arvon luomiseen ja hyödyntämiseen, sekä kilpailuetuun. Tutkimuksen empiirinen osuus on toteutettu laadullisena tapaustutkimuksena. Myös käsitteelliset julkaisut pohjautuvat empiiriseen dataan. Määrittääkseen miten ja miksi ekosysteemiset liiketoimintamallit syntyvät, sekä selvittääkseen kuinka ne kehittyvät ja muuttuvat, tämä väitöskirjatutimus kohdistuu erilaisiin ekosysteemisiin konteksteihin, erityisesti liiketoimintaekosysteemeihin ja innovaatioekosysteemeihin. Ekosysteeminen liiketoimintamalli korostaa, että arvon yhteinen luominen ja hyödyntäminen tulee perustua yhdessä määriteltyyn mahdollisuuteen ja kollektiiviseen arvolupaukseen. Tämä tutkimus osoittaa, että mutkikkaissa, monitahoisissa ekosysteemeissä, synergia on edellytys ekosysteemisen arvon ja kokonaiskilpailuedun rakentamiselle. Tutkimuksen tulokset indikoivat, että liiketoimintamalliajattelu pätee ei vain organisaation, mutta myös ekosysteemin tasolla, sillä ekosysteemin synergiaa ja onnistunutta orkestrointia voidaan edistää liiketoimintamallia hyödyntämällä.
200

Formation and governance of a healthy business ecosystem

Lappi, T. (Tuomas) 31 October 2017 (has links)
Abstract The objective of this dissertation is to identify how to make business ecosystem formation more efficient and how to evaluate ecosystem success capabilities. Business ecosystem formation consists of transition of a front-end phase ecosystem into an operational ecosystem. How the formation takes place and how it can be governed is approached through five formation elements: dynamics, strategy, governance, behaviour and evolution. The elements are defined based on literature review as the dissertation body of knowledge. Through inductive case studies and defined body of knowledge this dissertation presents as a synthesis a multidimensional model to support healthy business ecosystem formation. The model describes how ecosystem formation should be driven by key end customer requirements and how those contribute to ecosystem planning. Based on the key end customers it is possible to define initial joint value proposals and core service providers. This dissertation introduces roles of anchoring and moderator actors to business ecosystem discussion as actors leading the ecosystem formation and maintaining the ecosystem structure through strong relationships. The dissertation proposes conceptual models to assess ecosystem health and stakeholder’ salience. Ecosystem health can be assessed with sustainability, resilience, innovativeness and renewal capabilities. Importance of actors and their impact probability can be identified with salience assessment. Both assessment models enable ecosystem planners to monitor the formation progress and to focus governance activities. This dissertation is qualitative and inductive based on literature review and conducting empirical case studies in multiple business ecosystem type of environments in Finland and Taiwan. The dissertation consists of five academic publications and synthetization of them into this compilation book. The principal results of this dissertation include more detailed insights to support business ecosystem definition and scoping. Ecosystem formation expands the earlier contributions on business ecosystem evolution. Roles of anchoring and moderator actors complement the ecosystem roles enhancing planning. The assessment models provide for both practitioners and academics framework for evaluating ecosystem status. / Tiivistelmä Tämän väitöskirjan tavoitteena on tunnistaa kuinka liiketoimintaekosysteemin muodostumista voidaan tehostaa ja kuinka ekosysteemin kestävyyttä voidaan arvioida. Liiketoimintaekosysteemin muodostuminen käsittelee alkuvaiheen ekosysteemin muutosta toiminnalliseksi ekosysteemiksi. Ekosysteemin muodostumista ja muodostumisen hallinnointia käsitellään viidessä elementissä: dynamiikan, strategian, käyttäytymisen sekä evoluution kautta. Kirjallisuusperustaiset elementit muodostavat väitöskirjan tutkimusperustan. Induktiivisten tapaustutkimusten sekä tutkimusperustan pohjalta väitöskirja syntetisoi mallin joka tukee kestävän liiketoimintaekosysteemin muodostumista. Malli kuvaa kuinka muodostumisen tulee perustua valikoitujen loppuasiakkaiden vaatimuksiin ja kuinka nämä vaatimukset vaikuttavat ekosysteemin suunnitteluun. Loppuasiakkaiden perusteella määritetään ekosysteemin alustavat yhteiset arvoehdotukset sekä avainpalveluntarjoajat. Väitöskirja lisää ankkuri- ja moderaattoritoimijoiden roolit liiketoimintaekosysteemiä käsittelevään keskusteluun toimijoina, jotka edistävät ekosysteemin muodostumista ja ylläpitävät ekosysteemiä vahvojen suhteiden kautta. Väitöskirja esittää konseptuaaliset mallit ekosysteemin kestävyyden ja sidosryhmien merkittävyyden arviointiin. Ekosysteemin kestävyyttä arvioidaan jatkuvuuden, joustavuuden, innovatiivisuuden sekä uudistumiskyvyn kautta. Toimijoiden vaikutusvaltaa ja vaikutustodennäköisyyttä arvioidaan merkittävyysarvioinnilla. Ekosysteemin suunnittelutahot voivat hyödyntää malleja muodostumisen seurantaan sekä hallinnollisten toimien keskittämiseen. Väitöskirjatutkimus on kvalitatiivien ja induktiivinen perustuen kirjallisuuskatsaukseen sekä soveltuviin tapaustutkimuksiin Suomessa ja Taiwanissa. Väitöskirja koostuu viidestä tutkimusartikkelista ja niiden synteesinä laaditusta kirjasta. Väitöskirjan päätulokset sisältävät yksityiskohtaisia löydöksiä tukemaan ekosysteemin määrittämistä ja rajaamista. Ekosysteemin muodostuminen laajentaa aiempia tutkimustuloksia ekosysteemin evoluutiosta. Ankkuri- ja moderaattoritoimijoiden roolit täydentävät ekosysteemi roolivalikoimaa ja tukevat suunnittelua. Arviointimallit tarjoavat lähtökohdat sekä akateemiseen, että käytännölliseen liiketoimintaekosysteemin tilan arviontiin.

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