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Altman, Elizabeth J. "Platform and Ecosystem Transitions: Strategic and Organizational Implications." Thesis, Harvard University, 2015. http://nrs.harvard.edu/urn-3:HUL.InstRepos:16881891.
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By most conventional measures of corporate success (revenue, market capitalization, global brand growth, etc.) businesses operating as multi-sided platforms (MSPs) and their associated ecosystems constitute the majority of the fastest growing organizations in the global economy. In the strategy and economics fields there is a burgeoning literature related to MSP-governed businesses and their ecosystems primarily focused on pricing, growth, governance, and competitive considerations. Yet, in organizational studies and innovation there is a dearth of research analyzing characteristics of these businesses and their complementors and the managerial challenges they present. More specifically, an increasing number of mature incumbent organizations in a variety of industries are starting to operate in environments in which they either need to operate as MSP-based businesses, or join ecosystems governed by them to compete successfully and grow. This dissertation consists of two book chapters and one empirical project aligned with one overarching question: As information constraints approach zero and MSP-governed businesses and their complementors become increasingly more prevalent in the global economy, what are the strategic and organizational issues affecting incumbent organizations that choose to become MSPs or compete as complementors to them?
The first chapter, incorporating a forthcoming book chapter (see Altman, Nagle, & Tushman, 2015) is a theoretical study exploring the effects on management research and organizations when the costs of information processing, storage, and communication approach zero and organizations engage with a wide range of communities. As these information constraints are reduced, one effect is that MSP-based businesses and ecosystems thrive and impact large sectors of the economy. Thus, this chapter sets the context for the dissertation as it outlines the environment in which MSP-governed businesses and their complementors operate and introduces theoretical challenges posed by the growth of these networks.
The second chapter, an empirical paper, focuses on challenges encountered by incumbent organizations joining MSP-governed ecosystems as complementors. This project is a multi-year qualitative inductive field-based research study analyzing the transition of a well-known consumer technology product provider as it joins a powerful MSP-based ecosystem. The accessory organization enters an asymmetric power relationship encountering, and responding to, multiple types of dependencies. I identify three types of dependencies faced by the organization: technological, information, and values-based, and three response strategies the organization deploys: compliance, influence, and innovation. I suggest that these dependencies and responses are related to, but distinct from, extant work on power and dependencies. I also classify three phases of complementor maturity through which the organization passes. I induce a grounded theory model identifying relationships between the concepts and discuss theoretical implications.
The final chapter, also a forthcoming book chapter (see Altman & Tripsas, 2015), addresses organizational identity implications of transitions mature organizations undergo as they shift from product to MSP-based business models in which business considerations include network effects and interdependence. This chapter explains that organizational identity may affect, and may be affected by, product-to-platform transitions. It suggests that an organization must question its identity and modify it to be consistent with its re-defined business model.
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Rocha, Juan Carlos. "Regime Shifts in the Anthropocene." Doctoral thesis, Stockholms universitet, Stockholm Resilience Centre, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-116894.
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Abrupt and persistent reconfiguration of ecosystem’s structure and function has been observed on a wide variety of ecosystems worldwide. While scientist believe that such phenomena could become more common and severe in the near future, little is known about the patterns of regime shifts’ causes and consequences for human well-being. This thesis aims to assess global patterns of regime shifts in social-ecological systems. A framework for comparing regime shifts has been developed as well as a public forum for discussing knowledge about regime shifts, namely the regime shift database. The most common drivers and expected impacts on ecosystem services have been identified by studying the qualitative topology of causal networks as well as the statistical properties that explain their emergent patters. Given that long time series data for ecosystems monitoring is rather sparse, and experimenting with ecosystems at the scales required to understand their feedback dynamics is rarely an option; we also proposed an indirect computationally based method for monitoring changes in ecosystem services. I hope the results here presented offer useful guidance for managers and policy makers on how to prioritize drivers or impacts of regime shifts: one take home message is that well-understood variables are not necessary the ones where most managerial efforts need to be taken. I also hope the scientific community rigorously criticize our results, but also acknowledge that when doing theoretical or empirical work, our methods tend to ignore the multi-causal nature of regime shifts. By bringing back multi-causality to the scientific debate, I hope our results offer new avenues for hypothesis exploration and theory development on the human endeavour of understanding Nature.Transiciones críticas o cambios de régimen en ecosistemas se definen como reconfiguraciones abruptas de su estructura y función. Estos cambios, en ocasiones inesperados, se han documentado en una gran variedad de ecosistemas en todo el planeta. Algunos científicos proponen que en el futuro cercano dichos fenómenos pueden volverse más frecuentes y severos. Sin embargo, sabemos muy poco sobre las causas y consecuencias potenciales para el bienestar humano. El objetivo de esta tesis es evaluar patrones globales de cambios de régimen en sistemas socio-ecológicos. Un marco conceptual para comparar cambios de régimen y un foro público de discusión sobre el estado del arte en su conocimiento fue desarrollado en la base de datos virtual www.regimeshifts.org. Las causas más comunes y los impactos en servicios ecosistémicos más esperados han sido identificados estudiando las propiedades topológicas de redes causales, así como las propiedades estadísticas que explican sus propiedades emergentes. Dado que experimentar con ecosistemas a la escala adecuada para capturar sus mecanismos causales generalmente no es una opción, y dado que la disponibilidad de datos de largo plazo necesarios para monitorear cambios de régimen son la excepción y no la regla, proponemos un método indirecto computacional para monitorear cambios en servicios ecosistémicos. Espero que los resultados sean de utilidad para actores encargados del diseño de políticas o del manejo de ecosistemas, especialmente espero que ofrezcan una guía sobre cómo priorizar causas y consecuencias de estos cambios de régimen: una lección clave es que las variables que mejor entendemos o las que más monitoreamos no son necesariamente aquellas en las que debemos enfocar las estrategias de manejo. También espero que la comunidad científica critique con rigor nuestros resultados, pero a su vez reconozca que tanto el trabajo empírico y teórico como los métodos que comúnmente se utilizan para estudiar cambios de régimen tienden a ignorar su naturaleza multi-causal. Al enfatizar la diversidad de sus causas, espero que los resultados ofrezcan nuevas posibilidades para la exploración de hipótesis y el desarrollo de teorías para entender mejor la Naturaleza.
Abrupt och ihållande omkonfigurering av ekosystems struktur och funktion har observerats i en mängd olika ekosystem världen över. Forskning visar på att dessa fenomen antas bli vanligare och allvarligare inom vår närmsta framtid. Kunskapen kring dessa s.k. regimskiften är dock bristfällig, framförallt kring dess konsekvenser för mänskligt välbefinnande. Denna avhandling syftar till att bedöma globala mönster av regimskiften. Ett ramverk för att jämföra regimskiften, samt ett offentligt forum, “the regime shifts database”, för att främja diskussion och sprida kunskap om regimskiften, har utvecklats. De mest förekommande drivkrafter och effekter på ekosystemtjänster har identifierats genom att studera kvalitativa topologiska och kausala nätverk, samt de statistiska egenskaperna som förklarar deras framväxande mönster. Då långvariga tidsserier av ekosystemövervakning är få, och då de experiment som krävs för att förstå regimskiftens återkopplingsdynamik sällan är möjliga, föreslås också en indirekt beräkningsmetod för övervakning av förändringar i ekosystemtjänster. Resultaten från denna avhandling ämnar ger värdefull vägledning för beslutsfattare om prioriteringsordningen mellan olika typer av drivkrafter och effekter av regimskiften. En viktig slutsats är att gedigen kunskap om en viss variabel inte nödvändigtvis ger området där insatser bör tillsättas. Vidare, genom att föra tillbaka multi-kausalitet till den vetenskapliga debatten, erbjuder avhandlingen nya vägar för hypotesprövning och teoriutveckling inom vår gemensamma strävan att förstå Naturen.
At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 1: Manuscript. Paper 2: Manuscript. Paper 4: Manuscript.
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Nordemar, Ingrid. "Human Abuses of Coral Reefs- Adaptive Responses and Regime Transitions." Doctoral thesis, Stockholm : Institutionen för systemekologi, Univ, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-250.
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Meyer, Daniel. "TRANSITIONS AND RESILIENCE IN THE FROZEN COMMONS : LINKING AQUACULTURE, KRILL FISHERY, GOVERNANCE AND ECOSYSTEM CHANGE IN THE SCOTIA SEA, SOUTHERN OCEAN." Thesis, Stockholms universitet, Stockholm Resilience Centre, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-64512.
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The Antarctic krill (Euphausia superba) is a forage fish species that is increasing inimportance for Southern Ocean fisheries and world aquaculture production. However, thisspecies also has a fundamental role in the Scotia Sea food-web and is the main conservationtarget for the region’s natural resource management organization - the Commission for theConservation of Antarctic Marine Living Resources (CCAMLR). The aim of this thesis istherefore to examine the inter-relationship between CCAMLR, krill fishery and the Scotia Seaecosystem in the Southern Ocean, as well as broader socio-economical and ecological settingssince 1970s and measure system resilience. The premise here is that the current krill-regime inthe Scotia Sea must be understood as a complex adaptive system (CAS) of social, ecologicaland economical attributes that operates over different temporal and spatial scales. Thus, byapplying the framework of a social-ecological system (SES), together with the adaptive cycleheuristic model, both quantitative and qualitative data is revised and integrated. Two alternatemanagement states are identified within the krill-regime; an early krill fishery state (1972 –1991), and an ecosystem based governance state (1991 - 2010). Resilience is however fadingin the Scotia Sea due to a combination of cross-scale attributes, in a range from low krilldensity (n/m¯²), increased competition for marine resources between predators and krillfishery, to elevated demand and global market prices of non-food commodities by theaquaculture sector in Asia, thus, moving the Scotia Sea towards an unknown fish-regime.Although such future regime is still retained by the region’s slow changing physical variablessuch as sea ice and seasonality, as well as the adaptive management capacity of CCAMLR,the sudden appearance of an undesirable regime in the Scotia Sea would probably havecomprehensive socio-ecological consequences if reached.
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Elf, Julia, and Ludvig Svensson. "Standardization in Sustainability Transitions : A Study on Stakeholder Attitudes and Power Relations During the Standardization Process in the Vehicle-to-Grid Ecosystem." Thesis, KTH, Skolan för industriell teknik och management (ITM), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-264259.
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The electrification of the transportation sector plays an important role in the sustainability transition as successful electric vehicle (EV) integration allows for the reduction of CO2 emissions. Moreover, bidirectional capabilities of the EVs (vehicle-to-grid) further facilitate this transition by supporting the electricity grid while lowering the cost of ownership of EVs when revenues from grid-supporting services are split between stakeholders. Due to sustainability challenges facing several domains, fundamental transformation processes are needed to transition away from our current global energy system. However, with the strong inertia of the current system together with the sheer complexity and vexed interests during transitions, neither private markets nor government agencies seem likely to spur this transition on their own. Transitions are thus political processes, in which standards can play an important role since they point to the direction of the transition. This thesis investigates the role of standardization in sustainability transitions. The aim was to improve the understanding of the diverse stakeholder attitudes towards the standardization process of the communication protocol between the vehicle and its charging equipment. While exploring this topic, the thesis further aimed to investigate the power relations that govern the interactions and coordination efforts between the diverse stakeholders involved in the vehicle-to-grid (V2G) standardization processes. To achieve this, a qualitative study was conducted where two transcripts from the California Energy Commission, adding up to a total of 667 pages, were coded in a mixed inductive-deductive manner. In addition, as a complement, 13 expert interviews were conducted. The results showed that power was expressed by actors on (and between) all levels in the system. Mutual dependency was the most frequently expressed power relation among the actors. The mutual dependency was assumed to be widely present due to the interdependent nature between the components in the V2G system. The automotive manufacturers were observed to have a strong position in the vehicle-to-grid ecosystem and it was noted that other actors conformed with their political and/or economic goals. Another finding related to power was the sense of powerlessness and frustration expressed by actors on all levels, likely enabling the status quo to prevail. There was also clear frustration towards policymakers concerning the lack of policy direction and actors expressed the need for market signaling. The policymakers seemed to adhere to both disruptive innovations and the existing regime, causing uncertainty in policy decisions. The empirics also showed that the standardization discussions have little focus on competition between standards at this point of the transition. The debate seemed to rather be shaped by the conflict between advocates and opponents of standardization, where the opponents argued against standardization due to fear of prematurely mandating a single standard. Advocates dominated over opponents at this point of the transition and the communication standard, ISO 15118 seemed to have significant industry support. Automotive manufacturers were found to be the most vocal stakeholder group against standardization. Furthermore, the results highlighted the functions and features of standards commonly mentioned in the V2G standardization discussions, where compatibility, market signaling, and future proof features belonged to the most frequently mentioned.Elektrifieringen av transportsektorn spelar en central roll för omställningen till ett hållbart energisystem eftersom elbilar bidrar till minskade utsläpp av koldioxid. Bidirektionella laddningsmöjligheter (V2G) kan möjliggöra omställningen ytterligare genom att stötta svaga elnät på lokal nivå samtidigt som funktionen kan minska kostnaderna för att äga en elbil. Fundamentala omställningar krävs för att lösa de hållbarhetsutmaningar som flera industrier står inför men på grund av komplexiteten i dessa system kan varken privat eller offentlig sektor driva denna förändring på egen hand. Omställningsprocessen är en politisk process där standardisering kan spela en viktig roll eftersom de kan indikera vilken riktning omställningen rör sig mot. Den här uppsatsen undersöker därför standardiseringens roll i hållbarhetsomställningar. Syftet var att öka förståelsen av olika aktörers ståndpunkter i standardiseringsprocessen av kommunikationen mellan en elbil och dess laddstation. För att undersöka detta ämne granskades även maktförhållanden som genomsyrar en standardiseringsprocess. Detta gjordes genom kvalitativ kodning av två transkriberade diskussioner om standardisering från California Energy Commission vilka totalt uppgick till 667 sidor. Utöver detta hölls 13 intervjuer som komplement. Resultatet visade att makt utövades av aktörer på samtliga nivåer i systemet. Ett ömsesidigt beroende kunde identifieras mellan aktörerna. Detta antogs vara framträdande på grund av de beroendeförhållanden som uppstår sig då samtliga aktörer krävs för att ett V2G-system ska fungera. Vidare observerades att maktutövande som förstärker och reproducerar existerande strukturer och institutioner uttrycktes av många aktörer i V2G-ekosystemet. En annan observation var att biltillverkare verkar ha en stark position i V2G-ekosystemet och det noterades att andra aktörer anpassade sig efter deras politiska och/eller ekonomiska mål. Ett ytterligare resultat var att det fanns en känsla av maktlöshet och frustration på alla nivåer i systemet vilket bidrog till upplevelsen av status quo. Det fanns en tydlig frustration speciellt mot beslutsfattare vilken grundade sig i bristen på tydliga riktlinjer. Beslutsfattare verkade anpassa sig såväl mot disruptiv innovation som till den existerande regimen vilket orsakade passivitet och osäkerhet vid beslutsfattande. Eftersom ramverket Multi-Level Power-in-Transition som användes för analysen inte tar hänsyn till att beslutsfattare kan svara både mot dominanta och mer radikala makrotrender, modifierades ramverket något innan det appliceras på empirin. Vidare visade analysen att det inte pågår någon konkurrens mellan standarder i denna fas av omställningen, däremot identifierades en konflikt mellan förespråkare och motståndare till standardisering där motståndarna var oroliga över att det var för tidigt att ge mandat åt en enskild standard. Förespråkare dominerade över motståndare i denna fas av omställningen och kommunikationstandarden ISO 15118 verkade ha betydande stöd från industrin. Biltillverkare befanns vara de aktörer som till största grad motsatte sig standardisering. Resultaten gav ytterligare en inblick i de egenskaper hos standarder som vanligtvis nämndes i diskussioner om kommunikationsstandarder. Några av de egenskaper som regelbundet belystes som viktiga var kompatibilitet och att den bör vara framtidssäker. En ytterligare viktig funktion med standardisering ansågs vara att ge tydliga signaler till marknaden.
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de, Schutter Elisabeth Marie Louise, Stefan Giljum, Tiina Häyhä, Martin Bruckner, Syed Ali Asjad Naqvi, Ines Omann, and Sigrid Stagl. "Bioeconomy Transitions through the Lens of Coupled Social-Ecological Systems: A Framework for Place-Based Responsibility in the Global Resource System." MDPI AG, 2019. http://dx.doi.org/10.3390/su11205705.
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Bioeconomy strategies in high income societies focus at replacing finite, fossil resources
by renewable, biological resources to reconcile macro-economic concerns with climate constraints.
However, the current bioeconomy is associated with critical levels of environmental degradation.
As a potential increase in biological resource use may further threaten the capacity of ecosystems to
fulfil human needs, it remains unclear whether bioeconomy transitions in high income countries are
sustainable. In order to fill a gap in bioeconomy sustainability assessments, we apply an ontological
lens of coupled social-ecological systems to explore critical mechanisms in relation to bioeconomy
activities in the global resource system. This contributes to a social-ecological systems (SES)-based
understanding of sustainability from a high income country perspective: the capacity of humans to
satisfy their needs with strategies that reduce current levels of pressures and impacts on ecosystems.
Building on this notion of agency, we develop a framework prototype that captures the systemic
relation between individual human needs and collective social outcomes on the one hand (microlevel)
and social-ecological impacts in the global resource system on the other hand (macro-level).
The BIO-SES framework emphasizes the role of responsible consumption (for physical health),
responsible production (to reduce stressors on the environment), and the role of autonomy and selforganisation
(to protect the reproduction capacity of social-ecological systems). In particular, the
BIO-SES framework can support (1) individual and collective agency in high income country
contexts to reduce global resource use and related ecosystem impacts with a bioeconomy strategy,
(2) aligning social outcomes, monitoring efforts and governance structures with place-based efforts
to achieve the SDGs, as well as (3), advancing the evidence base and social-ecological theory on
responsible bioeconomy transitions in the limited biosphere.
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Nagel, Franziska. "Mobile Commerce : The retail ecosystem in the technological transition." Thesis, Linnéuniversitetet, Institutionen för organisation och entreprenörskap (OE), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-78383.
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The purpose of this study is to problematize the technological transition from traditional retail to mobile commerce, its following challenges, and its impact on organizations. Further, to highlight what companies need in order to consider the implemention of this technological transition. Finally, this study aims to tackle synergies that are exposed in this study that defines factors which drive the technological transition from traditional retail to m-commerce.
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Gill, Wendy Jane. "The spatial characterisation of transitional areas between plant communities : a case study from upland Britain." Thesis, University of Plymouth, 1996. http://hdl.handle.net/10026.1/2196.
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The concept of the ecotone was formalised by Clements (1 905) as a boundary zone between plant communities. Little research exists on the ecological importance or the geographical variability of these zones. Two types of boundaries are acknowledged: the ecotone and the ecocline. The ecotone is a sharp boundary; the ecocline a gradual boundary. The term 'transitional area' is proposed here to more accurately describe these areas as this research demonstrates that a complex continuum exists between the two end points. Additionally, mosaics often complicate the nature of the transition and may form a boundary type in their own right. Upland plant communities represent important semi-natural habitats within the British Isles. Effective management depends on an understanding of their structure and function. This research is primarily concerned with the description of structure (spatial pattern and variability in floristic composition) but explanation of these patterns is only possible through an understanding of function (vegetation dynamics). Pilot studies determined an appropriate methodology for studying transitional areas. The approach progressed from a linear transect to a two-dimensional rectangular transect. The pilot studies also evaluated a range of methods for data analysis. Extended field sampling followed which included 23 sites in 4 locations: Dartmoor, Snowdonia, North York Moors and Barra, Western Isles of Scotland. Data analysis exposed the complexities of the transitional areas sampled but 'noise' often obscured the true characteristics. To overcome this a Species Ratio Index Model was devised to identify the strength of signal for each boundary. The final characterisation of transitional areas is based on three main components: ecotone, ecocline and mosaics, each displaying varying amplitude. Of the sites sampled, few boundaries revealed single characteristics and the majority were far more complex than their observed patterns implied. On the basis of this characterisation a classification is proposed which incorporates both natural and anthropogenic factors. The classification represents an important contribution to the understanding of boundary types. This study reinforces the significance of boundaries in the landscape. The potential for future research is great, particularly through the development of a predictive model for management purposes.
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Yang, Binbin. "Enhancing User Engagement in Electronic Commerce Through the Transition to a Digital Ecosystem." Thesis, Umeå universitet, Institutionen för informatik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-124532.
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Electronic Commerce (EC) companies are faced with a highly competitive environment today. Strengthening user engagement in digital ecosystems is a promising approach to increasing value co-creation. However, enterprise-oriented user engagement strategies examined in previous studies are relatively inadequate to meet today’s expectations. This paper looks to answer the question, “how to effectively strengthen user engagement to acquire a sustainable value co-creation system in EC.” A plausible user engagement strategy was revealed by analyzing a single case study in the music sector based on details of a digital ecosystem. Semi-structured interviews performed with company Xiami along with their users, show that the recognition of user-oriented needs and the expansion of user-driven demands are two key aspects for EC companies to maintain a sustainable growth of value co-creation.
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Lohani, Sapana. "Linking ecosystem services with state-and-transition models to evaluate rangeland management decisions." Diss., The University of Arizona, 2013. http://hdl.handle.net/10150/314685.
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Rangelands are a major type of land found on all continents. Though they comprise around 70% of the world's land area, knowledge of rangelands is limited and immature. Rangelands supply humans with food and fiber at very low energy costs compared to cultivated lands. They are inherently heterogeneous, highly variable in time and space. Rangeland management needs to consider the impacts of long-term vegetation transition. It needs a conceptual framework defining potential vegetation communities, describing the management induced transition of one vegetation community to another, and documenting the expected benefits provided by the various potential vegetation communities. The most widely used conceptual unit in the rangeland discipline is the "ecological site". Ecological sites can be an effective unit that should respond to management consistently and can help managers understand the site's potential to meet human needs. A state and transition model (STM) brings ecological sites and their potential vegetative states together to build a conceptual framework showing the major causes of transitions between states of an ecological site and thus helping make adaptive management decisions. Within the STM there is a need for an indicator of ecosystem health. Ecosystem services can be important to evaluate alternative states. Ecosystem services do not pass through a market for valuation, though often the cost would be very high if, through mismanagement, the ecosystem is no longer capable of providing those services. Vegetation communities are constantly facing reversible or irreversible transitions triggered by natural events and/or management actions. The framework generated in this study is significant in using remote sensing to generate state and transition models for a large area and in using ecosystem services to evaluate natural and/or management induced transitions as described in the STM. This dissertation addresses the improvement of public rangelands management in the West. It applies geospatial technologies to map ecological sites and states on those sites, characterizes transitions between states and selects a desired state to manage towards based on a systematic assessment of the value of flows of environmental services. The results from this study are an evaluation of improved draft ecological site maps for a larger area using remote sensing images, a simplified state-and-transition model adapted to remote sensing capabilities to study transitions due to climatic events and management practices, and a constrained optimization model that incorporates ecosystem services and the simplified STM to evaluate management costs and conservation benefits. The study showed that brush treatment is the most effective management practice to cause state transitions. The highest increase in the high cover state was by 24%. Areas under grazing and drought show slow transitions from brush to grass and also after prescribed fire vegetation take at least two years to recover.
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Picchi, Paolo. "Enhancing the relationship between the landscape of energy transition and the ecosystem services." Doctoral thesis, Università degli studi di Trento, 2015. https://hdl.handle.net/11572/368647.
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Governments adopt strategies to follow the objective Europe 2020 and focus on the development of Renewable Energy Technologies, RET, to improve the transition of the production of energy from fossil fuels sources to renewable energy sources, RES. More than decades before, the energy transition towards renewable energies emerges as a relevant objective of the European governments. The fluctuating prices of oil and the uncertainty on the future supply of fossil fuels open new challenges for communities to actuate an energy transition towards RES. The RET can afflict deeply the landscape structure and by this point of view the energy transition is one of the most relevant drivers in the landscape change of the last three decades. In several cases energy transition may face opposition from regions and communities because of the change that RET produce in local landscapes and related economic, cultural and ecological functions. This change has been defined as a conflict between the local narrative of the right to the landscape by local communities and the global narrative that aims at a low carbon future. Exploring the relationship between Ecosystem Services (ES) and Renewable Energy (RE), the conflict among a global perspective and a local perspective has been resumed by several authors as a trade-off among provisioning and regulating ES from one side and cultural ES from the other. The overcoming of this conflict can be based on bottom-up processes that enhance the energy transition starting by local organizations of communities that want to reach a self-sufficieny in renewable energy supply. Transition management is possible if we produce innovation at local scale. An ES approach supports the transition management and the envisioning future energy landscapes by offering transparent trade-offs, exposing risks and benefits. If societies produce clean energy it may happen that RET afflict other ES. The main paradigm for the sustainability of a energy landscape is that the introduction of RET should not cause crucial trade-offs among the other ES, this is why this research wants to study this relationship, as several authors have already stressed. By the literature review it is possible to state a general gap of knowledge in integrated approaches in the evaluation of RET, considering diverse RES and ES provided by the landscape and evaluating a trade-off through a participatory process. To fulfill such gap and produce an enhancement of knowledge, this research follows the main objective of introducing a trade-off analysis into a design approach to formulate long-term visions for sustainable energy landscapes. The results we got indicate that it is possible to plan and design with the ES sustainable energy landscape.This process facilitates a sustainable energy transition of communities through a participatory landscape design that reduce the trade-off between the Renewable Energy and the ES supplies.
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Picchi, Paolo. "Enhancing the relationship between the landscape of energy transition and the ecosystem services." Doctoral thesis, University of Trento, 2015. http://eprints-phd.biblio.unitn.it/1509/1/tesi_paolo_picchi.pdf.
Full textAbstract:
Governments adopt strategies to follow the objective Europe 2020 and focus on the development of Renewable Energy Technologies, RET, to improve the transition of the production of energy from fossil fuels sources to renewable energy sources, RES. More than decades before, the energy transition towards renewable energies emerges as a relevant objective of the European governments. The fluctuating prices of oil and the uncertainty on the future supply of fossil fuels open new challenges for communities to actuate an energy transition towards RES. The RET can afflict deeply the landscape structure and by this point of view the energy transition is one of the most relevant drivers in the landscape change of the last three decades. In several cases energy transition may face opposition from regions and communities because of the change that RET produce in local landscapes and related economic, cultural and ecological functions. This change has been defined as a conflict between the local narrative of the right to the landscape by local communities and the global narrative that aims at a low carbon future. Exploring the relationship between Ecosystem Services (ES) and Renewable Energy (RE), the conflict among a global perspective and a local perspective has been resumed by several authors as a trade-off among provisioning and regulating ES from one side and cultural ES from the other. The overcoming of this conflict can be based on bottom-up processes that enhance the energy transition starting by local organizations of communities that want to reach a self-sufficieny in renewable energy supply. Transition management is possible if we produce innovation at local scale. An ES approach supports the transition management and the envisioning future energy landscapes by offering transparent trade-offs, exposing risks and benefits. If societies produce clean energy it may happen that RET afflict other ES. The main paradigm for the sustainability of a energy landscape is that the introduction of RET should not cause crucial trade-offs among the other ES, this is why this research wants to study this relationship, as several authors have already stressed. By the literature review it is possible to state a general gap of knowledge in integrated approaches in the evaluation of RET, considering diverse RES and ES provided by the landscape and evaluating a trade-off through a participatory process. To fulfill such gap and produce an enhancement of knowledge, this research follows the main objective of introducing a trade-off analysis into a design approach to formulate long-term visions for sustainable energy landscapes. The results we got indicate that it is possible to plan and design with the ES sustainable energy landscape.This process facilitates a sustainable energy transition of communities through a participatory landscape design that reduce the trade-off between the Renewable Energy and the ES supplies.
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ROCCA, MARIA. "ECOLOGICAL TRANSITION, BIODIVERSITY AND ECOSYSTEM SERVICES: THE CRUCIAL ROLE OF CONSUMERS AND PRODUCERS." Doctoral thesis, Università degli studi di Genova, 2022. https://hdl.handle.net/11567/1099494.
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Ecological transition is the main solution to climate change and environmental crises. It consists of a transition from an intensive and unsustainable production system to one that is economically, environmentally, and socially sustainable. Its importance has prompted policymakers and international organizations to include it as one of the main goals within national PNRR (Piano Nazionale di Ripresa e Resilienza) and international strategies (European Green Deal). But ecological transition can be reached only through a presence of natural resources variability, indeed, one of the best tools that could reach this goal is the biodiversity. Biodiversity is defined as the variability among living organisms from all sources, including diversity within species, between species, and ecosystems (Convention of Biological Diversity, 1992). A lack of biodiversity would cause the failure to achieve not only ecological transformation but also all 17 sustainable development goals (SDGs) defined by the U.N. in 2015. Rural areas are one of the largest hotspots of biodiversity as they protect biodiversity, prevent soil erosion, mitigate climate change, global warming, and hydrological risks, and promote ecological resilience. One of the main activities of rural areas is agriculture, which has both negative and positive environmental impacts. Sustainable agriculture enables the creation of a sustainable food chain and the production of ecosystem services that society requires. Ecosystem services are defined as direct and indirect contributions of ecosystems to human well-being (TEEB, 2010), which must underpin not only ecological transition but also economic growth to avoid the loss of biodiversity and the related depopulation of rural areas. One of the main problems with ecosystem services is the lack of market valuation; all beneficiaries tend to regard them as gifts from the ecosystem at no cost and for indefinite duration, which is not the case. It is evident by the approximately 1 million species that are now at risk of extinction and the drastic reduction of pollinators (Legambiente, 2021). Further, 60% of the population of fishes, birds, mammals, and reptiles have halved from 1970 to 2014. The actual beneficiaries of ecosystem services are producers, who use these services as productive inputs for all intents and purposes (i.e., benefit from the activity of pollinators), consumers/families (such as the benefit from walking in the mountains), and society (no coastal erosion due to the action of Posidonia). Therefore, to avoid a failure of their evaluation, it is necessary to work on both the supply and demand sides. On the one hand, incentives should be provided to producers to encourage them to produce ecosystem services as a competitive advantage. On the other hand, consumers should be encouraged to purchase sustainable and eco-friendly goods.
This study seeks to address these issues.
The first chapter focuses on abiotic soil ecosystem services, on which few studies have focused. Our goal is to estimate their social value through an experimental choice applied to a sample of 200 people with respect to two niche products grown in Liguria: Rotella apple and Moscatello wine. Before submitting the experimental choice to our sample, we identified five attributes with their respective levels that described our products: use of the soil (two levels), location of the product (two levels), knowledge of the soil (two levels), historical product conservation (three levels), and price (four levels). Once the results of the experimental choice were obtained, we applied a mixed multinomial logit model for the estimation. From the results, we found that consumers attributed a positive social value to abiotic soil ecosystem services; that is, their presence positively impacted their utility. This paper was presented at the international conference related to the EVA course called “Advances in Economic Valuation of Ecosystem Services for Public Policy and Ecosystem Accounting” held on May 25, 2022, as part of the TRANSUMARE festival, held in Genoa, Italy, May 23-28, 2022.
The second chapter addresses the supply side analysis. First of all, we defined the weaknesses and strengths of the internal and external contexts (SWOT: strengths, Weaknesses, Opportunities and Treats) in which 43 rural areas operate, using focus groups and meetings with various stakeholders (mayors, ANCI, park authorities, and rural firms). These 43 rural areas firms participated in two projects called CAMBIOVIA and BIODIVALP of Liguria Region. This study has two objectives: to rank the sustainability of the enterprises and to target policymakers’ strategic interventions necessary for the enhancement of these enterprises. In particular, the firms’ sustainability is interpreted from an economic, ecological and market perspective through composite macro-indicators. These sustainability indicators are based on both qualitative and quantitative data and firms are then ranked with respect to each category of macro-indicators through partially ordered sets methods. The methodology applied is entirely innovative and is represented by POSET, a partially ordered set hierarchization tool, which makes it possible to avoid offsets between data and consider their varying natures. In the second case, we used a multi-criteria analysis derived from a questionnaire submitted to 59 stakeholders to enable participatory consensus building, with the addition of a hierarchization approach for partially ordered sets due to the presence of qualitative variables. The results identified the following as the best tools: training, local brands and labels, and territorial networks. While referring to the classification of companies from an ecological, market, and economic point of view, it is seen how they differ for market and ecological sustainability while presenting the same situation, not good, in terms of economic status. This work was presented at the international conference related to the EVA course called “Advances in Economic valuation of Ecosystem Services for Public Policy and Ecosystem Accounting,” held on May 25, 2022, as part of the TRANSUMARE festival, held in Genoa, Italy, May 23-28, 2022.
The third chapter analyzes household behavior. This chapter aims to understand whether there is a space to engage consumers in an active demand attitude for ecosystem services that remain embedded in products. This is achieved by profiling consumers based on their consumption behaviors and analyzing their socio-economic-demographic characteristics. Latent class analysis (LCA) was used to study the consumption habits of a sample of 942 consumers. The results presented two groups of consumers. The first group presented less environmentally sustainable consumption habits, while the second group presented greater sustainability in their consumption. Regarding socio-economic-demographic characteristics, it was found that there were more educated consumers with more children and higher incomes in the second group. For group 1, we also observed that consumers’ consumption habits were due to their socio-demographic characteristics; in fact, because of their low level of income, they always purchased products from supermarkets. Meanwhile, a high percentage of consumers often bought PDOs (Protected Designation of Origin) and organic products and paid attention to animal and worker welfare as well as the information contained in the labels. With this work we underline the importance of consumers’ socio-economic-demographic characteristics for more sustainability behaviors.
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Cobb, Richard C., Katinka X. Ruthrof, David D. Breshears, Francisco Lloret, Tuomas Aakala, Henry D. Adams, William R. L. Anderegg, et al. "Ecosystem dynamics and management after forest die-off: a global synthesis with conceptual state-and-transition models." WILEY, 2017. http://hdl.handle.net/10150/626548.
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Broad-scale forest die-off associated with drought and heat has now been reported from every forested continent, posing a global-scale challenge to forest management. Climate-driven die-off is frequently compounded with other drivers of tree mortality, such as altered land use, wildfire, and invasive species, making forest management increasingly complex. Facing similar challenges, rangeland managers have widely adopted the approach of developing conceptual models that identify key ecosystem states and major types of transitions between those states, known as "state-and-transition models" (S&T models). Using expert opinion and available research, the development of such conceptual S&T models has proven useful in anticipating ecosystem changes and identifying management actions to undertake or to avoid. In cases where detailed data are available, S&T models can be developed into probabilistic predictions, but even where data are insufficient to predict transition probabilities, conceptual S&T models can provide valuable insights for managing a given ecosystem and for comparing and contrasting different ecosystem dynamics. We assembled a synthesis of 14 forest die-off case studies from around the globe, each with sufficient information to infer impacts on forest dynamics and to inform management options following a forest die-off event. For each, we developed a conceptual S&T model to identify alternative ecosystem states, pathways of ecosystem change, and points where management interventions have been, or may be, successful in arresting or reversing undesirable changes. We found that our diverse set of mortality case studies fit into three broad classes of ecosystem trajectories: (1) single-state transition shifts, (2) ecological cascading responses and feedbacks, and (3) complex dynamics where multiple interactions, mortality drivers, and impacts create a range of possible state transition responses. We integrate monitoring and management goals in a framework aimed to facilitate development of conceptual S&T models for other forest die-off events. Our results highlight that although forest die-off events across the globe encompass many different underlying drivers and pathways of ecosystem change, there are commonalities in opportunities for successful management intervention.
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Carnes, Jennifer L. "Response of Soils and Soil Ecosystems to the Pennsylvanian-Permian Climate Transitionin the Upper Fluvial Plain of the Dunkard Basin, Southeastern Ohio, USA." Ohio University / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1493571336373265.
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Meisterhans, Guillaume. "Dynamique de la structure génétique des communautés procaryotes en zone benthique côtière : caractérisation de la microflore des sédiments et des bivalves fouisseurs par empreintes moléculaires." Thesis, Bordeaux 1, 2012. http://www.theses.fr/2012BOR14494/document.
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Les structures des communautés procaryotes (diversité β) ont été caractérisées au sein de deux compartiments du benthos en milieu littoral: les sédiments et les bivalves fouisseurs.Dans les sédiments de surface, les communautés bactériennes et archéennes ont été ciblées par ARISA (Automated Ribosomal Intergenic Spacer Analysis) et T-RFLP (Terminal-Restriction Fragment Length Polymorphism) sur le gène codant pour l’ARN 16S respectivement. Sur 29 sites des zones intertidale et subtidale du Bassin d’Arcachon, les communautés procaryotes présentaient des patrons de distribution spatiale corrélés à ceux de la macrofaune benthique mais représentaient une faible diversité cumulée par habitat. L’extension à des écosystèmes proches (Vasière Ouest Gironde, Estuaire de la Gironde) a mis en évidence une forte proportion d’OTU (Operational Taxonomic Unit) rares et une diminution de la similarité entre les communautés avec l’éloignement géographique des écosystèmes. Chez les bivalves, les communautés bactériennes ont été caractérisées successivement à l’échelle de l’individu, de l’organe isolé et de l’espèce. Le suivi d’une cohorte de coques n’a pas montré d’influence de la présence du parasite Bucephalus minimus sur la structure de ces communautés à l’échelle de l’individu. En revanche, prises à l’échelle de l’organe en comparant la coque à la palourde, les communautés bactériennes associées aux bivalves se sont différenciées en fonction des organes (e.g branchies, tube digestif, reste des tissus), de l’habitat et/ou de l’espèceThe structures of prokaryotic communities (β diversity) were characterized in sediments and burrowing bivalves.In the sediments, the bacterial and archaeal communities were analyzed by ARISA (Automated Ribosomal Intergenic Spacer Analysis) and 16S RNA gene T-RFLP (Terminal-Restriction Fragment Length Polymorphism) respectively. In 29 subtidal and intertidal sites of the Arcachon Bay, the spatial patterns of prokaryotic and benthic macrofaunal communities were correlated whereas prokaryotic community species exhibited a low cumulated diversity per habitat. Extending to neighboring ecosystems (West-Gironde mud patch, Gironde estuary) revealed the occurrence of a high proportion of rare OTU (Operational Taxonomic Unit) and a decrease of community similarities with geographic distance among ecosystems.For the bivalves, the whole individual, the organ-scale and the species-scale were successively considered. A cockle cohort monitoring indicated no influence of the parasite Bucephalus minimus occurrence on bacterial community structure at the individual-scale. Comparing cockle and clam at the organ level demonstrated that bivalve associated bacterial communities could differ among organs (e.g. gills, digestive gut, others tissues), among habitats and/or between species
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Fernández, Méndez Pablo. "Facilitating transitions towards adaptive governance and management in estuarine socio-ecosystems: Institutional analysis and action research in the Doñana region." Doctoral thesis, Universitat de les Illes Balears, 2014. http://hdl.handle.net/10803/287516.
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El impacto acelerado de las actividades humanas está causando el aumento de los daños a los sistemas de soporte vital de la Tierra. En consecuencia, la necesidad de un cambio hacia el uso sostenible de los recursos naturales y los ecosistemas se ha defendido como una necesidad urgente por científicos y tomadores de decisiones. Esta tesis trata sobre las condiciones institucionales necesarias para dicho cambio en sistemas socio-ecológicos, a través de un estudio de caso en profundidad: la región de Doñana. En particular, la tesis se centra en la necesidad de transiciones desde estrategias de mando y control hacia enfoques más flexibles y adaptativos para la elaboración de políticas y la toma de decisiones, en particular, la gobernanza adaptativa y la gestión adaptativa. Para ello, se abordan tres preguntas de interés de investigación, amplias e interrelacionadas, utilizando un marco teórico que combina elementos de la dependencia de la trayectoria institucional y la teoría de la resiliencia. La primera pregunta de investigación se centra en la evaluación de la utilidad de un programa de investigación-acción cuyo objetivo fue introducir principios de gestión adaptativa en la interfaz investigación-gestión de la región de Doñana. La segunda pregunta se centra en mejorar la comprensión de las raíces de la rigidez institucional en sistemas socio-ecológicos maladaptativos. La tercera pregunta se centra en el potencial explicativo del emprendimiento y los discursos en su relación con los intereses político-económicos y el poder, como factores que contribuyen a la formación de sistemas socio-ecológicos a nivel local.
El enriquecimiento del conocimiento adquirido durante el programa de investigación-acción con el análisis en profundidad de las limitaciones institucionales arraigadas en factores históricos, permitieron la identificación de una serie de posibles vías que pueden ayudar a la transición hacia la gobernanza y la gestión adaptativas en la región de Doñana. Asimismo, este enriquecimiento permitió una especulación informada sobre el papel potencial de programas de investigación-acción como el que se describe en esta tesis, para cumplir con (y complementar) los requisitos para la participación pública y el aprendizaje social de la legislación de la Unión Europea – en particular, la Directiva Marco del Agua.
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Molin, Paulo Guilherme. "Dynamic modeling of native vegetation in the Piracicaba River basin and its effects on ecosystem services." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/11/11150/tde-06012015-111535/.
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Studies from the Forestry Institute of São Paulo State have shown that in the end of the 20th century, the native forest cover of the state of SP reached the maximum level of forest loss. From that point on, a period of forest increase and expansion started. Industrialization, law enforcement, economic benefits, and social pressure experienced in recent years are believed to be contributing to the preservation and regrowth of the native vegetation cover in certain locations. This study proposed to model the dynamics of native vegetation cover in the Piracicaba River basin (12,500 km²) in the state of São Paulo, Brazil, to evaluate possible effects of these changes in ecosystem services related to river flow & regulation and landscape structure, linking to biodiversity & habitat supported by forest patches. To achieve the proposal set out in this research, dynamic models of native vegetation were established. Thematic land cover maps of the years 1990, 2000 and 2010, originated from Landsat 5 TM images, formed the spatiotemporal basis of this study. With the aid of Dinamica EGO (a dynamic modeling software), three future scenarios were created, called status quo (SQ), no deforestation (ND) and riparian restoration enforcement (RRE). An analysis using weights of evidence was done to identify forest transition drivers. The drivers are divided into two groups, (1) environmental & physical, consisting of soil types, hydrographic network, rainfall and presence of native forest fragments and (2) anthropic, consisting of population density, gross national product, road network, urban patches and predominant rural activities. Resulting scenarios were analyzed by means of landscape metrics to compare and qualify vegetation patches in relation to structure as proxy for supporting ecosystem services. Finally, Soil & Water Assessment Tool (SWAT), a hydrological model, was used to determine the influence of different forest scenarios in mean annual water yield and regulation processes throughout the basin, and, therefore, compare scenarios as to effects on regulating ecosystem services. Results show that forest transition is indeed occurring, with native vegetation cover parting from 24.4% in 1990, to 20.1% in 2000 and 21.8% in 2010. Scenario results were of 22.4% (SQ), 43.2% (ND) and 28.4% (RRE) for 2050. Forest loss was identified as a product of anthropogenic drivers while regrowth was of physical & environmental drivers. When the area was segmented, regions with greater environmental condition resulted in improved values of landscape structure. SQ scenario was the most affected, losing small patches of forest that could function as structural connectors, and therefore potentially affect biodiversity and habitat. Mean annual water yield was reduced with forest regrowth by as much as 10.3% in ND. We concluded that the dynamics occurring in the landscape and the proposed scenarios affect mean annual water yield, regulation and landscape structure, allowing us to discuss differences between the scenarios and the relation between forest dynamics, landscape structure, hydrology and overtime potential effects over regulating and supporting ecosystem services.Levantamentos do Instituto Florestal de São Paulo têm mostrado que no final do século XX a cobertura florestal nativa total do estado atingiu um patamar de perda e que se iniciou então um período de expansão. Rigidez de leis, fiscalização, benefícios econômicos, além de pressão social demonstrados nos últimos anos têm contribuído para essa expansão da vegetação nativa em certos locais. Este estudo propôs modelar a dinâmica da cobertura florestal nativa na bacia do Rio Piracicaba (12.500 km2), localizada no Estado de São Paulo, para averiguar os possíveis efeitos dessas mudanças nos serviços ecossistêmicos ligados à vazão e regulação de rios, além da própria estrutura da paisagem simulada, interligando-se com biodiversidade e habitat, promovidos pelos remanescentes florestais. Para atingir a proposta estabelecida nesta pesquisa, modelos de dinâmica da vegetação nativa foram desenvolvidos. Foram utilizados mapas temáticos de cobertura e uso do solo dos anos 1990, 2000 e 2010 originados a partir de imagens Landsat 5 TM. Com auxílio do software Dinamica EGO, especializado em modelagem da paisagem, criaram-se três modelos espaciais e temporais da dinâmica florestal, levando em consideração os cenários status quo (SQ), no deforestation (ND) e riparian restoration enforcement (RRE). Uma análise usando pesos de evidência foi utilizada para identificar as variáveis de transição florestal. As variáveis foram divididas em dois grupos, (1) físicas e ambientais, consistindo de tipos de solo, rede de drenagem, pluviosidade e presença de fragmentos florestais e (2) antrópicos, consistindo de densidade populacional, produto interno bruto, rede viária, zonas urbanas e predominância de atividade rural. Os cenários resultantes foram analisados por métricas de paisagem para fim de comparação e qualificação dos fragmentos em relação a sua estrutura, interligando-se aos serviços ecossistêmicos de suporte. Por último, foi realizada uma modelagem hidrológica usando o modelo Soil & Water Assessment Tool (SWAT) para averiguar a influência da mudança florestal na regulação de vazão de rios e portanto comparar os cenários em relação aos seus efeitos sobre serviços ecossistêmicos de regulação interligados à água. Resultados mostraram que transição florestal ocorreu, passando a cobertura florestal de 24,4% em 1990 para 20,1% em 2000 e então 21,8% em 2010. Cenários resultaram em uma cobertura florestal de 22,4% (SQ), 43,2% (LE) e 28,4% (RRE) para o ano de 2050. A perda de floresta foi identificada como produto de variáveis de natureza antrópica enquanto o ganho florestal foi de variáveis físicas e ambientais. Regiões com melhores condições ambientais resultaram em melhores valores de estrutura da paisagem. SQ foi afetado principalmente pela perda de pequenos fragmentos florestais que funcionam como conectores estruturais da paisagem, potencialmente afetando a biodiversidade e habitat. O deflúvio médio anual foi reduzido em até 10,3% com o incremento florestal observado em ND. Conclui-se que a cobertura florestal na paisagem e os cenários propostos afetam o deflúvio, regulação e a estrutura da paisagem, nos permitindo discutir nas diferenças entre cada cenário e a relação entre dinâmica florestal, estrutura da paisagem, hidrologia e potenciais efeitos nos serviços ecossistêmicos de suporte e regulação.
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Van, Scoyoc Matthew W. "A QUANTITATIVE APPROACH TO THE DEVELOPMENT OF ECOLOGICAL SITES AND STATE-AND-TRANSITION MODELS." DigitalCommons@USU, 2014. https://digitalcommons.usu.edu/etd/3075.
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The interaction of land-use and climate can cause non-linear “state” changes in ecosystems, characterized by persistent differences in structure and function. Changes in land-use and climate on the Colorado Plateau may be driving many ecosystems toward undesired states where energy-intensive measures are required to return to previous states. Landscape classification systems based on “ecological potential” offer a robust framework to evaluate ecological conditions. Ecological sites are a popular landscape classification system based on long-term ecological potential and are widely used throughout the western US. Ecological sites have been described extensively for rangelands and woodlands on DOI Bureau of Land Management lands; however, they have yet to be described on USDA Forest Service (USFS) lands. In this thesis, I describe a statistical approach to ecological site delineation and the development of state-and-transition models, diagrams that illustrate ecosystem dynamics and responses to disturbances. In Chapter 2, I used a large inventory dataset and multivariate statistical procedures to classify plots based on life zone, soils, and potential vegetation, effectively delineating statistical ecological site-like groups. Most of the statistical ecological sites matched ecological sites already described by the USDA Natural Resources Conservation Service (NRCS). Additionally, I described one new ecological site that has not been described by the NRCS in the Colorado Plateau region. In Chapter 3, I examined empirical evidence for alternative states in mountain ponderosa pine (Pinus ponderosa Lawson & C. Lawson) and upland piñon-juniper ecosystems. Using multivariate statistical procedures, I found that plots cluster into groups consistent with generalized alternative states identified in a priori conceptual models. Additionally, I showed that ponderosa pine clusters were true alternative states and piñon-juniper clusters were not true alternative states because they were confounded by similarities in climate. Ponderosa pine clusters were differentiated by overstory ponderosa pine density and corresponded to three states: current potential, high fuel load, and reduced overstory. These results illustrate the range of ecosystem variability that is present throughout the study area and present evidence for alternatives states caused by historical land-use. This project is the first to propose ecological sites and state-and-transition models on USFS lands in this region. These techniques could be applied to areas that do not have formally described ecological sites and state-and-transition models and could help identify ecological sites that may have been overlooked using other means of delineation. Additionally, these methods can be used to evaluate the range of ecological variability throughout an area of interest and to improved understanding of ecosystem dynamics.
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Goss, Charles W. "Influence of forest fragments on headwater stream ecosystems in agricultural landscapes." The Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1387536064.
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Schmidt, Martin [Verfasser], Gunnar [Akademischer Betreuer] Lischeid, Claas [Akademischer Betreuer] Nendel, Gunnar Gutachter] Lischeid, Claas [Gutachter] Nendel, and Christoph [Gutachter] [Thomas. "Fragmentation of landscapes: modelling ecosystem services of transition zones / Martin Schmidt ; Gutachter: Gunnar Lischeid, Claas Nendel, Christoph Thomas ; Gunnar Lischeid, Claas Nendel." Potsdam : Universität Potsdam, 2019. http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-442942.
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Schmidt, Martin [Verfasser], Gunnar [Akademischer Betreuer] Lischeid, Claas [Akademischer Betreuer] Nendel, Gunnar [Gutachter] Lischeid, Claas [Gutachter] Nendel, and Christoph [Gutachter] Thomas. "Fragmentation of landscapes: modelling ecosystem services of transition zones / Martin Schmidt ; Gutachter: Gunnar Lischeid, Claas Nendel, Christoph Thomas ; Gunnar Lischeid, Claas Nendel." Potsdam : Universität Potsdam, 2019. http://d-nb.info/1218405554/34.
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Sigovini, Marco <1980>. "Multiscale dynamics of zoobenthic communities and relationships with environmental factors in the Lagoon of Venice." Doctoral thesis, Università Ca' Foscari Venezia, 2011. http://hdl.handle.net/10579/1092.
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The thesis focuses on the macrozoobenthic community in the Lagoon of Venice. Main aspects investigated include: spatial and interannual variability of the community structure; the role of environmental factors in structuring benthic communities; spatial scales of variability of the community, also in relationship to variability scales of environmental factors. A three-year data set was analyzed. High interannual variability and spatial heterogeneity was verified. Multivariate structure and univariate descriptors were considerably related to environmental factors. A gradient from sea landwards in species richness and community composition was evidenced and related to the composite ecocline, mainly to seawater renewal and salinity. More complex spatial patterns were recognized. Univariate descriptors and multivariate structures follow different scales of variability. The results have implications for quality assessment of transitional ecosystems.La tesi analizza la comunità macrozoobentonica della Laguna di Venezia. Sono stati principalmente indagati: la variabilità spaziale e interannuale della struttura della comunità; il ruolo dei fattori ambientali; le scale spaziali di variabilità della comunità, in relazione alla scala di variabilità dei fattori ambientali. Il data set analizzato è relativo a tre anni. E' stata verificata un'elevata variabilità interannuale ed eterogeneità spaziale. Descrittori di struttura multivariata e univariate sono risultati notevolmente correlati ai fattori ambientali. E' stato evidenziato un gradiente da mare verso terra in merito al numero di specie e alla composizione della comunità, in relazione ad un ecocline composito, e principalmente a ricambio idrico e salinità. Sono emersi pattern spaziali più complessi. Descrittori univariati e strutture multivariate seguono diverse scale di variabilità. I risultati hanno implicazioni per la valutazione della qualità degli ecosistemi di transizione.
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Juhmani, Abdul-Salam Fayiz Ahmed <1984>. "Ecological and molecular analyses of macrophyte ecosystems for the assessment of the environmental health of coastal and transitional areas." Doctoral thesis, Università Ca' Foscari Venezia, 2018. http://hdl.handle.net/10579/15026.
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Degradation of coastal and transitional water quality by anthropogenic contaminants is an important concern worldwide. Identifying the patterns of biological response to contamination in the aquatic environment is essential for reliable evaluation of ecosystem health. The present study aims to use macrophytes to assess the ecological health status for marine coastal and transitional environments employing an integrated approach based on ecological indices and biomarkers as well as macrophyte associated microbial communities. The results obtained by the application of Macrophyte Quality index, oxidative stress biomarker and the diversity of macroalgal associated microbial community indicated that the ecological health status was affected by both metal contamination and trophic conditions.
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Lascoutx, Ruiz Alfredo. "A Politico-Ecological Approach of Transitional Spaces In Social Ecological Systems." Thesis, Université d'Ottawa / University of Ottawa, 2021. http://hdl.handle.net/10393/41987.
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As spatial properties that systems theoretically have, Socio-Ecological Systems are characterized by dynamism and mobility, therefore, are subject to changes in the space they occupy in the biosphere. In land ecosystems, these changes are understood as processes of evolution over time, or the result of extreme natural events, or transformation of the natural space induced by human activities.
These spatial changes produce effects on the land surface and groundwater of ecosystems colonized or penetrated by elements, individuals or populations belonging to other ecosystems. These are the so-called Transitional Spaces between ecosystems.
Throughout the continuous geographical space, these spatial transitions affect human and not human ecosystems in different ways. Given their ambiguous characteristics and their indefinite temporal location between urban, rural or natural spaces, transition spaces deserve to be investigated in order to know their properties and functions within the cartography that represents complex socio-ecological systems.
The research is conducted from a particular perspective of Political Ecology. For this I proceed to develop an epistemological exercise on the political ecology syntagma in order to approach its concept and object of study as a hybrid discipline between social sciences and natural sciences. Interdisciplinarity as a practice, a dialectic vision regarding anthropocentrism, environmental perception as a method for an ontology of human ecology, The ecosystem as a unit of spatial analysis. These would be some of the characteristics of my ecological-political perspective.
But what does transitional space mean for political ecology and what does it add to its theory? The question led me to seek the integral concept of ecosystem and to support myself in the General Systems Theory to analyze the notions of boundary and external environment as part of the classic concept of system. At that point, the notion of transitional spaces emerges implicit when recognizing the dynamic spatiality of other existing systems.
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Since the research is not linear but interdisciplinary and convergent, a brief anthology of geographic and socio-spatial political thought is presented in order to connect the issue of transitional spaces with the point of view of the social sciences. Various socio-geographical, deterministic, anthropocentric, Darwinian, Marxist, modernist theories give an overview of the issues related to space and nature. With the emergence of the spatial turn, new concerns for political sociology, geography and environmental sciences are explained by the phenomenon of urban growth at the global level.
In the same way, I introduce the topic of ecological spaces, specifically the concept of Ecotone, the space of transition between diverse natural ecosystems. The use of the notion of ecotone is based precisely on the perspective of the concept of political ecology developed previously.
This, in turn, will allow me to introduce the FLACAM methodology into the research, which among its components has the virtue of identifying and analyzing the spatial phenomenon of physical and social Interfaces, that is, spaces of transition within human ecosystems. Several graphics and charts show the potential properties and functions of different kind of existing interfaces and ecotones. My proposal converges in using these concepts as planning tools for transitional spaces identified as Rurban Regions and metropolitan areas.
A final reflection on the need for spatial research on global urban expansion and the theoretical and pragmatic advantages of the concept of intermediate cities closes the main body of the investigation.
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Lima, resque Antônio Gabriel. "Can the concept of ecosystem services facilitate agroecological transition in the Brazilian Amazon? Results from a mixed methods approach in Irituia and Paragominas, Pará state." Thesis, Paris, Institut agronomique, vétérinaire et forestier de France, 2020. http://www.theses.fr/2020IAVF0026.
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La proposition d'un modèle de développement qui concilie la conservation de l'environnement, en particulier des ressources forestières, et le développement socio-économique reste un défi à relever globalement, en particulier dans la région amazonienne. En raison de son ampleur, une attention particulière est portée à la portion brésilienne de l'Amazonie et plus précisément à ses différentes formes d’agriculture en raison de leur importance socio-économique et de leur potentiel d'altération des écosystèmes et des services écosystémiques (SE). Dans ce contexte, l’agriculture familiale apparaît incontournable pour promouvoir le développement rural durable. Malgré son importance, les acteurs locaux qui soutiennent les exploitations agricoles familiales sont confrontés à de nombreux défis pour promouvoir la transition agroécologique. La question générale de cette thèse est : Comment le cadre conceptuel des SE peut-il servir de base cognitive et opérationnelle pour soutenir la transition agroécologique ? Nous examinons deux municipalités contrastées situées dans la partie orientale de l'Amazonie brésilienne : Irituia, dont le secteur agricole est dominé par une agriculture familiale qui se tourne vers la biodiversification ; et Paragominas, qui présente une prédominance de l'agriculture industrielle à grande échelle, qui coexiste avec l'agriculture familiale. Nous avons adopté une perspective multi-acteurs, impliquant une diversité d'acteurs locaux (e.g., des décideurs politiques, des chercheurs, des agents de vulgarisation rurale, des agriculteurs). Nous avons implémenté une « approche de méthodes mixtes » combinant des méthodologies qualitatives, telles que des entretiens semi-directifs et l'observation participante, avec des méthodologies semi-quantitatives telles que des questionnaires et un jeu de rôles. Nous avons d'abord cherché à comprendre la perception qu'ont les acteurs locaux sur la coproduction des SE. Une diversité de SE est perçue par ces acteurs locaux. La perception des SE et de leur processus de coproduction diffère sensiblement selon le type d'activité exercée par les acteurs et leur municipalité. Nous montrons également comment la nature de leurs connaissances (plus scientifique ou empirique) joue sur leur manière de percevoir les SE. Nous avons par ailleurs cherché à comprendre l'importance de ces perceptions dans le processus de prise de décision sur l'utilisation des terres en étudiant l’influence sur ce processus de décision de certains facteurs contextuels externes à l’agroécosystème (notamment les marchés institutionnels) et internes (e.g., la main-d'œuvre, les coûts, les aspects cognitifs). Nous avons constaté que la réussite de la valorisation de l'agrobiodiversité au moyen de marchés institutionnels dépend de la manière dont ils sont administrés au niveau municipal. Des facteurs internes à l'exploitation, tels que le travail, les revenus, les valeurs, influencent également ce processus de prise de décision. Finalement, nous avons cherché à comprendre comment les connaissances générées lors des étapes précédentes pouvaient contribuer à rendre opérationnelle la transition agroécologique dans les sites d’étude. Ces connaissances ont contribué à révéler les attentes et les facteurs qui motivent les actions des acteurs locaux relatives à la gestion de l'utilisation des terres. Elles ont été obtenues par et utilisées pour alimenter des outils méthodologiques visant à soutenir la transition agroécologique. Au final, nous avançons que le cadre conceptuel de la coproduction des SE permet d’aller au-delà de l'exploration des éléments corrélés à la gestion des agroécosystèmes. Il constitue également un outil pertinent pour stimuler la communication sur le sujet entre les différents acteurs. La compréhension des mécanismes qui soutiennent la coproduction des SE et le partage des différentes connaissances et perceptions associées éveillent une prise de conscience collective en faveur de la transition agro-écologiqueThe proposal of a model of development that reconciles environmental conservation, especially of forest resources, and socioeconomic development is still a challenge to be achieved worldwide, especially in the Amazon region. Due to its amplitude, the Brazilian portion of the Amazon is a matter of great concern nationally and internationally. Agriculture stands out in the Brazilian Amazon for its socioeconomic importance and its tremendous potential to alter ecosystems and the provision of ecosystem services (ES). Among the different forms of agriculture (i.e. large and small farmers), family farms are key players for promoting rural sustainable development. Despite its importance, local actors supporting family farms face numerous challenges to promote agroecological transition of these farms. The general question that we want to contribute to with this thesis is: How can the conceptual framework of ES serve as a cognitive and operational basis to support the agroecological transition? We carried out this research in two contrasting municipalities in the eastern part of the Brazilian Amazon, Irituia and Paragominas. The farming sector of the first study site is dominated by family farming, which is often biodiversified. Contrastingly, large-scale industrial agriculture predominates in the second study site, although it coexists with family farming. We adopted a multi-actor perspective, with the participation of a heterogeneous set of local actors (e.g. policy makers, researchers, rural extension agents, farmers) related to rural issues. We implemented a “mixed methods approach” combining well-tested qualitative methodologies, such as semi-directive interviews and participant observation, with semi-quantitative methodologies such as questionnaires and a role-playing game. We first aimed to understand the perception of different local actors about ES and their co-production process. We observed that, in general, a diversity of ES is perceived by local actors. The perception of ES and the different possible ways to co-produce these ES differ significantly among actors. The type of activity performed by the stakeholders and their municipality are the main factors influencing their perception of ES co-production. The type of knowledge (more scientific or empirical) was also relevant to distinguish between the ways to perceive ES. We also sought to understand the importance of these perceptions in the decision-making process on land use. We investigated some contextual factors that influence this decision making process, focusing on factors external (notably institutional markets) and internal (e.g. labor, costs, cognitive aspects) to the agroecosystem. We realized that these markets are important for valuing agrobiodiversity, but this will depend on how they are managed at a municipal level and on the local institutional landscape. Accordingly, the agroecosystem may evolve towards agroecological or non-agroecological standards. Internal factors in the farm, such as labor, money, values also influence this decision making process. Finally, we sought to understand how the knowledge generated previously could contribute to operationalize the agroecological transition in our two study sites. Knowledge about ES issues generated in our research site contributed to disclose the expectations and factors that drive the actions of stakeholders regarding land use management. This knowledge was obtained through and was used to feed methodological tools to support agroecological transition. Finally, we highlight that the conceptual framework of ES co-production not only enables exploring elements correlated to agroecosystem management, it also serves as a viable tool to stimulate the communication of different actors on the subject. A better understanding of the mechanisms underlying the co-production of ES and the sharing of different knowledge and perceptions can support more collective awareness toward agroecological transition
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Alochet, Marc. "Rupture technologique et dynamique d’une industrie : la transition vers l’électromobilité Will the scale-up of electric vehicles (EV) disrupt the architecture of the automotive industry? Automobile industry, towards an electric autonomous mobility service industry? A sociotechnical transition-based approach Systemicinnovation and project learning: from firm to ecosystem learning capability How do servitization impact on project management? Some examples from the emergence of MaaS Are Chinese regulations shaping the worldwide EVs industry?" Thesis, Institut polytechnique de Paris, 2020. http://www.theses.fr/2020IPPAX088.
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Des réglementations strictes obligent les constructeurs à investir massivement dans la production de véhicules électriques. L'électrification est une innovation systémique et sa massification devrait perturber la conception dominante des véhicules. "Cette perturbation pourrait-elle déstabiliser durablement l'architecture d’une industrie considérée comme très résiliente ?"Une étude empirique de la chaîne de valeur de la traction électrique, confirme, à ce jour, la résilience de cette industrie dont les constructeurs automobiles restent l'acteur central et que l'électrification seule ne suffit pas à déstabiliser. Mais les innovations technologiques, les nouveaux défis sociétaux, les nouveaux acteurs puissants de la mobilité influencent l'avenir de cette industrie. "Cette combinaison de facteurs internes et externes à l'industrie pourrait-elle favoriser une dynamique de rupture ?" En analysant 10 cas de services de mobilité innovants au niveau mondial, cette thèse identifie 3 types idéaux : "service de mobilité ajouté au produit", "robotaxi", "plate-forme ouverte de mobilité territorialisée". Si le premier est une extension naturelle de l'activité des constructeurs, les deux derniers ont le potentiel de déstabiliser cette industrie. Une comparaison, entre la Chine et l'Europe, de la gouvernance des réglementations environnementales, indique que la Chine est en situation d’imposer désormais ses normes dans le monde entier grâce à une capacité de planification alliant directivité, intrusion et agilité. Théoriquement, cette thèse confirme les théories stratégiques et l’utilisation du paradigme de la STT pour étudier les transitions dans cette industrie. Elle contribue aux domaines de la gestion de l'innovation et de la servitisation en proposant un espace de conception pour le développement des services de mobilité et confirme que le projet est un important vecteur d'apprentissage dans un écosystème naissant. Elle soutient l'hypothèse d'une avalanche de causalités convergentes conduisant à la déstabilisation de l'architecture historique de l'industrie automobile et que les modes de régulation entre ces différents facteurs vont façonner ces déstabilisations potentiellesStrict regulations force global players to invest heavily in the production of electric vehicles. Electrification is a systemic innovation whose massification should disrupt the vehicle dominant design. “Could this disruption durably destabilize the industrial architecture of a sector, considered as very resilient?”An empirical study on the electric traction value chain, confirms, to date, the resilience of this industry as carmakers remain the focal actor: electrification alone is not enough to destabilize this industry!But, technological innovations, new societal challenges, new powerful players in the mobility market influence the future of this industry.“Could this combination of factors internal and external to the industry facilitate a disruptive dynamic?”By analyzing 10 case studies of innovative mobility services worldwide, this thesis identifies 3 ideal types: “mobility service added to product”, “robotaxi”, “territorialized open mobility platform”. If the first one is a natural extension of The carmakers' business, the last two have the potential to destabilize the automotive industry.An empirical comparison, between China and Europe, of the governance of environmental regulations, states that China is now in capacity to impose its standards worldwide through a planning capacity combining directiveness, intrusiveness and agility.Theoretically, it confirms strategic theories and the interest of building upon the STT paradigm to shed light on transitions in this industry. It contributes to innovation management and servitization fields by proposing a design space for the development of mobility services and confirms that project is an important learning vector in a nascent ecosystem. This thesis supports the hypothesis of an avalanche of converging causalities leading to the destabilization of the historical architecture of the automotive industry. In accordance with the theory of transitions, the modes of regulation between these different factors will shape these potential destabilizations
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Ntsonde, Joël. "Entre utopie et action collective, comment accompagner la transition des territoires vers l'économie circulaire ? : Le cas de la commande publique dans le secteur de la construction." Thesis, Université Paris sciences et lettres, 2020. http://www.theses.fr/2020UPSLM035.
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L’économie circulaire rencontre un succès grandissant dans la société et apparaît comme un levier majeur pouvant être mis au service de la transition écologique. Mais de manière assez paradoxale, l’engouement actuel autour de ce nouveau modèle semble plus lié à sa dimension utopique qu’à sa solidité scientifique. Ce constat soulève plusieurs questions telles que : pourquoi autant d’acteurs sont attirés par un concept qui reste encore flou ? Qu’est ce que les sciences de gestion peuvent-elles nous apprendre sur ce phénomène ? Comment l’économie circulaire peut-elle contribuer à favoriser une transition écologique ? Jusqu’à présent la littérature académique s’est peu intéressée à la dimension utopique de l’économie circulaire et à son impact en termes d’action collective. Afin d’étudier ce phénomène, la thèse s'intéresse aux mécanismes cognitifs, organisationnels et inter-organisationnels qui sous-tendent la transition d’un territoire vers l'économie circulaire. A partir du cas de la commande publique dans le secteur de la construction, nous questionnons ensuite les "transition studies" (Markard et al., 2012) pour proposer un modèle de transition conceptualisant les mécanismes qui peuvent permettre à des acteurs économiques, sociaux et politiques d’accompagner la transition de leur territoire vers l’économie circulaire. Ce modèle part des processus qui amènent des entrepreneurs à concevoir des innovations, puis conceptualise les mécanismes qui conduisent des organisations publiques et privées à coopérer avec ces entrepreneurs, avant d’expliciter les mécanismes à partir desquels cette dynamique d'action collective peut matérialiser la transition d’un territoireCircular economy is meeting with growing success in society and appears to be a major lever that can be put to the service of the ecological transition. But paradoxically enough, the current craze around this new model seems more linked to its utopian dimension than to its scientific solidity. This observation raises several questions such as: why are so many actors attracted by a concept that is still unclear? What can management science teach us about this phenomenon? How can circular economy help foster an ecological transition? Until now, academic literature has paid little attention to the utopian dimension of circular economy and its impact in terms of collective action. In order to study this phenomenon, the thesis focuses on the cognitive, organizational and inter-organizational mechanisms that underlie the transition of a territory to circular economy. Using the case of public procurement in the construction sector, we then question the transition studies (Markard et al., 2012) to propose a transition model conceptualizing the mechanisms that can enable economic, social and political actors to support the transition of their local area to circular economy. This model starts from the processes that lead entrepreneurs to design innovations, and then conceptualizes the mechanisms that lead public and private organizations to cooperate with these entrepreneurs, before explaining the mechanisms from which this dynamic of collective action can materialize the transition of a territory
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MANZINI, ALESSANDRA. "Dinamiche di transizione in ecovillaggi del Senegal." Doctoral thesis, Università IUAV di Venezia, 2022. http://hdl.handle.net/11578/319927.
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La ricerca di dottorato è stata un viaggio alla ricerca di intuizioni trasformative multiverso che emergono dal movimento degli eco-villaggi senegalese e da esperienze alternative anti-egemoniche. La domanda da cui sono partita si interroga su cosa possiamo apprendere dalle esperienze di transizione socio-ecologica di successo degli ecovillaggi del Senegal.
La prima questione ha generato riflessioni su quali metodi di emersione delle forme di transizione impiegare per includere una pluralità di voci e prospettive. I metodi attivati sono in linea con principi etico-filosofici inspirati al pensiero decoloniale. Tali metodi si propongono di restituire la complessità dei diversi sistemi insediativi e le differenze esistenti in significati, traiettorie, visioni, cosmologie, valori e pratiche delle diverse forme di transizione. Si è optato pertanto per la costruzione di un disegno valutativo multidimensionale comparativo in grado di comprendere spunti trasformativi e aspetti etico-filosofici appresi dalle scuole africane, ed effettuare un’analisi di sensitività relativa all’incidenza delle pratiche antropiche e delle condizioni climatiche sulle dinamiche di transizione. La ricerca di correlazione tra forme di transizione e spinte sociali ha portato ad evidenziare tra i casi studio le esperienze anti-egemoniche di resistenza, quelle di adattamento proattivo e all’estremo opposto di resa. Questi ultimi rinviano a casi di migrazione dovuti a crisi ambientali irreversibili.
La ricerca ha applicato una metodologia variegata, utilizzando spettacoli di teatro-forum come pratica decoloniale per discutere i problemi della transizione ecologica con gli abitanti dei luoghi e un itinerario metodologico diversificato, che ha seguito un disegno valutativo ricorsivo per aggiornare le ipotesi in itinere. I risultati mostrano la co-presenza di molteplici prospettive africane endogene, che tendono ad arricchire il messaggio "Africa-Mondo". Il messaggio è veicolato dal linguaggio con cui le nicchie (eco-villaggi) traducono il termine transizione ecologica, dalle forme di vita che riproducono nella loro spazialità, dalla resistenza delle connessioni di legame e dalla condivisione degli ecosistemi sociali nelle prassi e nelle cosmo-visioni, nonostante le perturbazioni del colonialismo, capitalismo e la poli-esposizione alla globalizzazione. Le cosmo-visioni si relazionano con gli immaginari e le spiegazioni fornite dalle comunità sull'origine del mondo e sul loro rapporto con la terra. Le auto-narrazioni dei luoghi presentano modi alternativi di abitare la terra e di relazionarsi con i non umani, più che con gli umani. I risultati della ricerca consentono di riflettere sul senso delle sfide ecologiche contemporanee in prospettiva africana. Si tratta di risultati parziali ottenuti mettendo in tensione esplorazioni sul campo con ‘paradigmi africani’ emergenti. La tensione non si è dimostrata indolore su entrambi i versanti. Se da un lato esperienze di connessione e cosmologie sembrano produrre forme di vita in parziale equilibrio con la natura, connotate da cooperazione sociale e legami che ne arricchiscono la qualità, dall’altro i nuovi ‘paradigmi africani’ sembrano difettare in autonomia, ma soprattutto incontrano difficoltà di legittimazione continentale. Non è un caso che i tentativi di traduzione delle cosmologie nelle pratiche di vita generino ecologie ibride che, oltre a mettere in discussione genealogie ‘scientifiche’ coloniali, sollevano il più generale quesito di cosa siano oggi le Afriche. La scoperta di quali risorse rappresentino leve di una transizione ecologica endogena su cui scommettere per rafforzare l’autonomia locale e la meta-stabilità di sistemi socio-ecologiche potrebbe aprire significative piste di ricerca per l’Africa e i suoi luoghi.The PhD research was a journey in search of multiverse transformative insights emerging from the Senegalese eco-village movement and alternative anti-hegemonic experiences. The question I started from asks what can we learn from the successful socio-ecological transition experiences of Senegal's eco-villages. The first question generated reflections on which methods of emerging forms of transition to employ in order to include a plurality of voices and perspectives. The methods applied are in line with ethical-philosophical principles inspired by de-colonial thinking. These methods aim to reveal the complexity of different settlement systems and the existing differences in meanings, trajectories, visions, cosmologies, values and practices of different forms of transition. We therefore opted for the construction of a comparative multidimensional evaluative design capable of encompassing transformative cues and ethical-philosophical aspects learnt from African schools, and carry out a sensitivity analysis on the impact of anthropic practices and climatic conditions on transition dynamics. The search for correlations between forms of transition and social drives led to the identification among the case studies of anti-hegemonic experiences of resistance, those of proactive adaptation and at the opposite extreme of surrender. The latter refer to cases of migration due to irreversible environmental crises. The research applied a hybrid methodology, using theatre-forum performances as a decolonial practice to discuss issues of ecological transition with local inhabitants, and a diverse methodological itinerary, which followed a recursive evaluative design to update hypotheses in progress. The results show the co-presence of multiple endogenous African perspectives, which tend to enrich the "Africa-World" message. The message is conveyed by the language with which the niches (eco-villages) translate the term ecological transition, the forms of life they reproduce in their spatiality, the resilience of bonding connections and the sharing of social ecosystems in practices and cosmo-visions, despite the disruptions of colonialism, capitalism and poly-exposure to globalisation. Cosmo-visions relate to the imaginaries and explanations provided by communities about the origin of the world and their relationship to the earth. The self-narratives of places present alternative ways of inhabiting the earth and relating to non-humans, rather than humans. The research findings allow us to reflect on the meaning of contemporary ecological challenges from an African perspective. They are partial results obtained by tensioning field explorations with emerging 'African paradigms'. The tension has not proved painless on both sides. While experiences of connectedness and cosmologies seem to produce forms of life in partial balance with nature, connoted by social cooperation and ties that enrich their quality, the new 'African paradigms' seem to lack autonomy, but above all they encounter difficulties with continental legitimacy. It is no coincidence that attempts to translate cosmologies into life practices generate hybrid ecologies that, in addition to questioning colonial 'scientific' genealogies, raise the more general question of what Africa is today. The discovery of which resources represent levers of an endogenous ecological transition on which to focus in order to strengthen local autonomy and the meta-stability of socio-ecological systems could open up significant avenues of research for Africa and its places.
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Guttal, Vishwesha. "Applications of nonequilibrium statistical physics to ecological systems." Columbus, Ohio : Ohio State University, 2008. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1209696541.
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Derot, Jonathan. "Utilisation des données de MAREL Carnot pour la compréhension des mécanismes des extrêmes dans la qualité des eaux à Boulogne-sur-Mer." Thesis, Littoral, 2014. http://www.theses.fr/2014DUNK0375/document.
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L'objectif principal de cette thèse est la caractérisation des dynamiques hautes fréquance en milieu côtier et en particulier leurs extrêmes, par l'intermédiaire de l'étude de série temporelle biogéochimiques à long terme enregistrées par des systèmes automatisés. Les bases de données hautes fréquences utilisées dans cette étude proviennent majoritairement du programme MAREL, qui a été mise en oeuvre par l'IFREMER. Des séries temporelles basses fréquences provenant des programmes de surveillance du littoral SOMLIT (CNRS, INSU) et SRN (Ifremer) sont mises à contribution pour appuyer l'importance des systèmes automatisés. La méthode EMD (Empirical Mode Decomposition) nous a servi de base dans de nombreuses analyses pour étudier ces séries temporelles. Nous avons aussi utilisé des méthodes plus classiques empruntées aux domaines de l'analyse numérique et de la turbulence. Cette études se décompose en 3 parties, et plusieurs annexes. Les matériels et méthodes sont présentés dans la première partie. Dans la seconde partie, la méthode EMD nous a permis de mettre en avant les fortes fluctuations contenues dans les blooms, ainsi que de mener des analyses spectrales grâce à un couplage avec la transformée de Hilbert. L'analyse en composante principale (ACP) a mis en avant les principaux forçages exercés sur la production primaire et les profils de température SOMLIT laissent supposer un impact de la stratification sur l'intensité des blooms. Dans la troisième partie, nous avons mené une étude comparative entre les données basses fréquences et hautes fréquences. Et deux méthodes de cross-corrélation (TDIC et co-spectre) nous ont permis de définir une échelle caractéristique de transition entre les températures de la Manche occidentale et orientale. En annexe, nous avons testé la robustesse de différentes méthodes d'analyses spectrales quant au manque de données dans les séries temporelles, qui est un problème inhérent aux bases de données enregistrées par des systèmes automatisés, et nous avons reproduit un article qui est en cours de soumissionThe main objective of this thesis is the characterization of high frequency dynamics in coastal areas and in particular their extremes, through the study of long-term biodeochemical time series registered by automated systems. The majority of high-frequency data sets used in this study came from MAREL program. The low-frequency time series from coastal monitoring programs SOMLIT (CNRS, INSU) and SRN (Ifremer) are employed to support the importance of automated systems. The EMD (Empirical Mode decomposition) method has provided a basis for us to study several of these time series. We also have used some methods more classical borrowed from numerical analysis field and turbulence. This study is organized in three chapters, and several appendices. The first chapter is devoted to the material and method. In the second chapter, using the EMD method we have highlighted the strong fluctuations contained in the blooms, and we have performed spectral analyzes. The principal component analysis (PCA) highlighted the main forcing exerted on primary production and SOMLIT temperature profiles suggest an impact of stratification on the intensity of blooms. In the third chapter, we conducted a comparative study between low-frequency and high-frequency data. Two cross-correlation methods (TDIC and co-spectra) allowed us to define a characteristic transition scale between the temperatures of the western and eastern English Cahnnel. In appendices we tested the robustness of different spectral analysis methods about the missing data in the time series, which is an underlying problem in the database registered by automated systems, and we reproduce a paper, which is under submission
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Corti, Roland. "Assèchement des cours d'eau : effets sur les communautés d'invertébrés et la dynamique de la matière organique particulaire." Phd thesis, Université Claude Bernard - Lyon I, 2013. http://tel.archives-ouvertes.fr/tel-00828092.
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Les transitions terrestre-aquatique jouent un rôle primordial dans le fonctionnement des écosystèmes. Dans les cours d'eau qui cessent de s'écouler périodiquement, ces transitions se développent latéralement au travers des zones ripariennes mais aussi longitudinalement le long du lit du cours d'eau. L'objectif de ce travail de thèse était de déterminer les effets de ces transitions terrestre-aquatique dans les lits des cours d'eau sur les communautés d'invertébrés terrestres et sur dynamique de la matière organique particulaire, un processus écologique fondamental au fonctionnement des cours d'eau. Les résultats montrent que communautés d'invertébrés ripariens sont peu dépendantes des ressources aquatiques du cours d'eau mais sont essentielles au maintien de la diversité en invertébrés dans les lits asséchés. La matière organique est transportée et se décompose par à coup lors des conditions aquatiques, influençant potentiellement la disponibilité en nutriments dans les réseaux hydrographiques
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Larose-Filotas, Élise. "Structure et dynamique des communautés multi-espèces : le rôle de l’espace." Thèse, 2009. http://hdl.handle.net/1866/3161.
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Cette thèse porte sur le rôle de l’espace dans l’organisation et dans la dynamique des communautés écologiques multi-espèces. Deux carences peuvent être identifiées dans les études théoriques actuelles portant sur la dimension spatiale des communautés écologiques : l’insuffisance de modèles multi-espèces représentant la dimension spatiale explicitement, et le manque d’attention portée aux interactions positives, tel le mutualisme, en dépit de la reconnaissance de leur ubiquité dans les systèmes écologiques. Cette thèse explore cette problématique propre à l’écologie des communautés, en utilisant une approche théorique s’inspirant de la théorie des systèmes complexes et de la mécanique statistique. Selon cette approche, les communautés d’espèces sont considérées comme des systèmes complexes dont les propriétés globales émergent des interactions locales entre les organismes qui les composent, et des interactions locales entre ces organismes et leur environnement.
Le premier objectif de cette thèse est de développer un modèle de métacommunauté multi-espèces, explicitement spatial, orienté à l’échelle des individus et basé sur un réseau d’interactions interspécifiques générales comprenant à la fois des interactions d’exploitation, de compétition et de mutualisme. Dans ce modèle, les communautés locales sont formées par un processus d’assemblage des espèces à partir d’un réservoir régional. La croissance des populations est restreinte par une capacité limite et leur dynamique évolue suivant des mécanismes simples de reproduction et de dispersion des individus. Ces mécanismes sont dépendants des conditions biotiques et abiotiques des communautés locales et leur effet varie en fonction des espèces, du temps et de l’espace. Dans un deuxième temps, cette thèse a pour objectif de déterminer l’impact d’une connectivité spatiale croissante sur la dynamique spatiotemporelle et sur les propriétés structurelles et fonctionnelles de cette métacommunauté. Plus précisément, nous évaluons différentes propriétés des communautés en fonction du niveau de dispersion des espèces : i) la similarité dans la composition des communautés locales et ses patrons de corrélations spatiales; ii) la biodiversité locale et régionale, et la distribution locale de l’abondance des espèces; iii) la biomasse, la productivité et la stabilité dynamique aux échelles locale et régionale; et iv) la structure locale des interactions entre les espèces. Ces propriétés sont examinées selon deux schémas spatiaux. D’abord nous employons un environnement homogène et ensuite nous employons un environnement hétérogène où la capacité limite des communautés locales évoluent suivant un gradient.
De façon générale, nos résultats révèlent que les communautés écologiques spatialement distribuées sont extrêmement sensibles aux modes et aux niveaux de dispersion des organismes. Leur dynamique spatiotemporelle et leurs propriétés structurelles et fonctionnelles peuvent subir des changements profonds sous forme de transitions significatives suivant une faible variation du niveau de dispersion. Ces changements apparaissent aussi par l’émergence de patrons spatiotemporels dans la distribution spatiale des populations qui sont typiques des transitions de phases observées généralement dans les systèmes physiques.
La dynamique de la métacommunauté présente deux régimes. Dans le premier régime, correspondant aux niveaux faibles de dispersion des espèces, la dynamique d’assemblage favorise l’émergence de communautés stables, peu diverses et formées d’espèces abondantes et fortement mutualistes. La métacommunauté possède une forte diversité régionale puisque les communautés locales sont faiblement connectées et que leur composition demeure ainsi distincte. Par ailleurs dans le second régime, correspondant aux niveaux élevés de dispersion, la diversité régionale diminue au profit d’une augmentation de la diversité locale. Les communautés locales sont plus productives mais leur stabilité dynamique est réduite suite à la migration importante d’individus. Ce régime est aussi caractérisé par des assemblages incluant une plus grande diversité d’interactions interspécifiques. Ces résultats suggèrent qu’une augmentation du niveau de dispersion des organismes permet de coupler les communautés locales entre elles ce qui accroît la coexistence locale et favorise la formation de communautés écologiques plus riches et plus complexes.
Finalement, notre étude suggère que le mutualisme est fondamentale à l’organisation et au maintient des communautés écologiques. Les espèces mutualistes dominent dans les habitats caractérisés par une capacité limite restreinte et servent d’ingénieurs écologiques en facilitant l’établissement de compétiteurs, prédateurs et opportunistes qui bénéficient de leur présence.This thesis is a study of the role of space in the organization and dynamics of multi-species ecological communities. Two weaknesses can be identified from previous theoretical studies concerned with the spatial dimension of ecological communities: the scarcity of multi-species models based on a spatially explicit representation of space, and the lack of attention toward positive interspecific interactions, such as mutualism, despite the recognition of their ubiquity in ecological systems. This thesis explores this problematic by adopting a theoretical framework based on complex system theory and statistical mechanics. Following this approach, ecological communities can be viewed as complex systems whose global properties emerge from the local interactions between the organisms that composed them, and between the organisms and their environment. The first objective of this thesis is to develop a multi-species metacommunity model which is spatially explicit, individual-based, and centered on a general interspecific interaction web containing exploitation, competition as well as mutualism. In this model, local communities are created by an assembly process whereby species are drawn from a regional pool. Population growth is restricted by a carrying capacity and its dynamics is driven by simple reproduction and dispersal mechanisms acting at the level of single individual. These mechanisms depend on the biotic and abiotic conditions of the local communities and their effect varies with species, time and space. The second objective of this thesis is to determine the impact of an increasing spatial connectivity on the dynamics, and structural and functional properties of this metacommunity. More precisely, we set out to evaluate different community properties under changes in the level of species dispersal: i) the similarity in local community composition and its patterns of spatial correlations, ii) the local and regional diversity and the local species abundance, iii) the local and regional biomass, productivity and dynamical stability, and iv) the structure of the local interaction webs. These properties are examined under two spatial schemes. First, we employ a homogeneous environment, and second we employ a heterogeneous environment whereby the carrying capacity of local communities evolves along a gradient. In general, our results reveal that spatially distributed ecological communities are extremely sensitive to the modes and levels of species dispersal. Their spatiotemporal dynamics as well as their structural and functional properties can undergo profound changes in the form of significant transitions under slight changes of the level of dispersal. These changes are also highlighted by the emergence of spatiotemporal patterns in the spatial distribution of the populations, which are characteristics of phase transition generally observed in physical systems. The metacommunity presents two dynamical regimes. In the first regime, corresponding to weak levels of species dispersal, the assembly dynamics promotes the emergence of species-poor but stable communities made of abundant and strongly mutualistic species. The metacommunity has a high regional diversity since weakly connected communities conserve a distinct assemblage of species. On the other hand, in the second regime, corresponding to strong dispersal rates, regional diversity decreases at the benefit of an increase in local diversity. Local communities are more productive but their stability is reduced due to the important migration of individuals. This regime is also characterized by assemblages containing a richer diversity of interspecific interactions. These results suggest that an augmentation in the level of species dispersal permits organisms to couple local communities together which increases local coexistence and promotes the organization of richer and more complex ecological communities. Finally, our results suggest that mutualism is fundamental to the organization and persistence of ecological communities. Mutualistic species dominate in habitats characterized by a restricted carrying capacity and serve as ecological engineer by facilitating the establishment of competitors, predators and opportunists which benefit from their presence.
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Lee, Hong-Yuh, and 李鴻裕. "The Transition of Post-3G Mobile Communications Industry In a Global Ecosystem." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/10305990921249821783.
Full textAbstract:
博士國立交通大學
科技管理研究所
98
The application service of Third Generation (3G) mobile telecommunications is gradually progressing in developed countries. By setting a maximum rate for mobile data service, the European Union (EU) is able to anticipate the substantial growth in the consumers’ mobile internet demand for data transmission in European countries, as well as to integrate the wide range of applications and services into the broadband mobile networks. In the post-3G era, the new technology and innovation is changing the ecosystem of the value chain.For instance, the iPhone with iTune service has brought big impact to the existing players in the value chain.Therefore, trying to forsee the changing and migration of the mobile communication industry and catch up the opportunity is the key aspect in the management of technology. This research is based on the industry ecology theory to discover the trend of post-3G mobile communication industry and the shifting of value chain.A theoretical analysis model is established to evaluate the interdependence as well as value sharing of players inside the ecosystem.In addition, this model give an assessment and recommendation to Taiwan communication company the way of leveraging resources in the ecosystem to create competitiveness and overcome the challenge. With regard to Fourth Generation (4G) mobile communication system, which of the two technological standards, LTE or WiMAX, will prevail? This research uses the industry ecology theory to assess the merits and drawbacks of both LTE and WiMAX in the midst of industry trends. The results show that although WiMAX proved superior to LTE in certain technological capabilities, the abundant 3G ecology resources provide LTE with a strong leverage and thus allowing it to develop its way to the mainstream of the 4G mobile communication industries.
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Lemos, Ana Brito. "Evaluating ecosystem services trade-offs due to land use changes: transition to an irrigated agriculture landscape." Master's thesis, 2017. http://hdl.handle.net/10451/27672.
Full textAbstract:
Tese de mestrado em Biologia da Conservação, apresentada à Universidade de Lisboa, através da Faculdade de Ciências, 2017Os serviços dos ecossistemas são os benefícios que o ser humano obtém a partir dos ecossistemas e que são necessários para o seu bem-estar. Estes são classificados pelo Millennium Ecossistem Assessment em quatro categorias principais: provisionamento, suporte, regulação e culturais. As alterações nos ecossistemas (por exemplo alteração do tipo de uso do solo ou poluição) podem ter impacto na capacidade dos ecossistemas produzirem esses serviços. Uma das maiores alterações do uso do solo a nível mundial foi a substituição de ecossistema naturais por ecossistemas agrícolas (aumento da área agrícola em 466% desde 1700). A agricultura fornece e depende de vários serviços do ecossistema. A paisagem agrícola não só suporta a produção de alimentos, fibras e combustíveis, mas também providencia uma grande variedade de benefícios públicos como o sequestro de carbono e paisagens esteticamente agradáveis. Exemplos destes benefícios são a reciclagem de nutrientes, o controlo do microclima local, regulação dos serviços hidrológicos locais, regulação da abundância de organismos não desejados. Os serviços dos ecossistemas dependem das espécies presentes no local para poderem ser produzidos. No entanto, a intensificação da agricultura é uma das principais ameaças a biodiversidade. A agricultura moderna simplificou os sistemas agrícolas tradicionais e substituiu as funções biológicas originalmente providenciadas por comunidades diversas de organismos, com uma maior introdução de energia e agroquímicos no sistema. As formas industriais de agricultura têm como objetivo remover as limitações à produtividade das plantas. Estas práticas de gestão podem afetar a condição dos ecossistemas através de impactos, como por exemplo, a erosão do solo, a qualidade da água e a emissão de gases efeito de estufa. Estes efeitos podem ser exacerbados em regiões semiáridas, onde é feita irrigação para ultrapassar a limitação da disponibilidade de água. Tendo isto em consideração, a qualidade do habitat é um fator importante para a agricultura, uma vez que uma elevada biodiversidade promove muitos serviços do ecossistema que sustentam a agricultura. A polinização é outro dos serviços necessários à agricultura, visto que a maioria das plantações dependem ou beneficiam da presença de polinizadores. No entanto, várias espécies de polinizadores estão em vias de extinção e as populações de polinizadores estão a diminuir, sendo a expansão e a intensificação da agricultura uma das suas principais ameaças. O armazenamento de carbono é outro serviço de ecossistema que pode ser comprometido pelas práticas agrícolas e que simultaneamente pode ser extremamente valioso para a agricultura. O carbono pode ser encontrado em vários compartimentos do ecossistema, sendo um deles a biomassa acima do solo (por exemplo árvores). Quando a paisagem é convertida para agricultura este carbono é perdido. Melhorar o carbono orgânico do solo é uma das formas da agricultura ajudar a diminuir esta perda de carbono, e pode também promover a produção de alimentos, sendo dessa forma também um serviço fornecido à agricultura. O solo tem a capacidade de reciclar os a matéria orgânica e de promover a circulação de nutrientes no sistema. Os organismos do solo degradam e decompõem a matéria orgânica, promovendo assim, por exemplo, a fertilidade dos solos. A capacidade de decomposição do solo pode ser alterada devido ao crescimento de plantas e à fertilidade do solo ser mantida não através da natural circulação de nutrientes no sistema, mas através da introdução de fertilizantes que podem ter consequências negativas tanto para os ecossistemas (e.g. poluição dos cursos de água) como para a saúde humana (e.g. problemas respiratórios). Alem disso, a constante movimentação dos solos pode ter como consequência o aumento da erosão dos mesmos e ainda a perda de matéria orgânica, podendo afetar assim a capacidade de circulação de nutrientes. Avaliar os serviços dos ecossistemas assim como os seus trade-offs pode ser utilizado para demonstrar o valor relativo desses serviços, tornando mais evidente os custos das atividades que os degradam. Mapear os serviços do ecossistema e os trade-offs que ocorrem na alteração do tipo de uso do solo, pode ser de bastante auxílio na sua gestão, especialmente se este mapeamento for realizado com resolução ao nível da propriedade e da cultura agrícola. Deste modo, este trabalho tem como objetivo avaliar os trade-offs nos serviços do ecossistema devidos a alteração do uso do solo numa paisagem que sofreu uma alteração de uma agricultura extensiva para uma agricultura de irrigação. Para isto, será utilizado o software InVest, recorrendo a dados de uma área agrícola irrigada pela barragem do Alqueva (bloco de irrigação de Monte Novo). Isto permitirá avaliar os trade-offs dos serviços do ecossistema na área e melhorar estratégias de gestão dos mesmos. De forma a recolher os dados necessários para as bases de dados foram realizados tanto pesquisa bibliográfica como recolha de dados no local de estudo. Amostragens de aves (qualidade do habitat) e polinizadores (serviço de polinização) foram realizadas no terreno e complementadas com pesquisa bibliográfica posterior. Para a análise da decomposição foi utilizado um protocolo estandardizado, o Tea Bag Index. Para isto foi recolhido solo no campo e o protocolo foi realizado no laboratório. Na transição de uma agricultura extensiva para intensiva observou-se um aumento da área irrigada de 4.75% para 56.32%. Como consequência os resultados mostram alterações ao nível dos vários serviços estudados. Quanto à qualidade de habitat verificou-se um decréscimo dos valores deste serviço. Os resultados mostraram também que as galerias ripícolas são o uso do solo com maior índice de qualidade de habitat. Estas comunidades naturais são de extrema importância, uma vez que podem promover a conectividade entre outras manchas de habitat. O mapa atual mostra um menor armazenamento de carbono que o mapa histórico (menos 10%). O uso do solo com maior armazenamento de carbono é as galerias ripícolas para os dois mapas. No mapa atual o carbono é armazenado principalmente nas áreas irrigadas com plantações permanentes, como os olivais e as vinhas. Uma das limitações da avaliação deste serviço do ecossistema, é ter sido baseado em dados da bibliografia, pelo que seria interessante reavaliar este serviço com medições realizadas no campo para os vários compartimentos de carbono existentes. Quanto ao serviço de circulação de nutrientes medido através da taxa de decomposição, não se encontraram diferenças significativas entre os vários usos do solo em análise. Estes resultados podem estar a ser verificados pelo pouco tempo que passou desde o inicio da irrigação. Uma vez que o protocolo utilizado para medir a taxa de decomposição foi conduzido em laboratório, os valores obtidos representam o potencial de decomposição dos solos e não a sua taxa de decomposição real. Quando todos os serviços foram considerados no seu conjunto, as galerias ripícolas mostraram ser o uso do solo com maior capacidade de providenciar o conjunto dos serviços do ecossistema analisados, sendo que os usos do solo irrigados e com maior impacto humano são aqueles que mostram uma menor capacidade de fornecer estes serviços. Assim, medidas como o aumento do número de manchas de usos do solo como galerias ripícolas e montado, de forma a que estes possam aumentar a conectividade das áreas naturais e fornecer serviços do ecossistema a LULC que não os possuam pode ser uma das medias a ser implementada de forma a otimizar tanto a agricultura como os serviços do ecossistema no bloco de irrigação de Monte Novo. Este estudo mostra que a intensificação agrícola através da substituição de culturas extensivas por irrigadas levou a alterações nos serviços dos ecossistemas na área de estudo. A construção de um modelo espacialmente explicito usando programas como o InVest são uma boa ferramenta para analisar e avaliar as alterações que uma área sofre devido às alterações no uso do solo e devem ser tidos em consideração quando são planeadas medidas de gestão com objetivo de promover uma agricultura mais sustentável.
Ecosystem services are the benefits people obtain from ecosystems. Land-use and related land-cover modifications caused by agriculture aim at increasing the supply of selected or bundles of ecosystem services, on which human societies depend. However, agriculture also causes un-intended changes in ecosystem functioning and associated ecosystem services of which agriculture depends. These services are provided by varied species, but because agriculture is a major driver of biodiversity loss, those services are affected. Of special concern is the shift to intensive agriculture, which causes the most losses of biodiversity and associated ecosystem services. For example, pollinators have a major role in agriculture food production, yet agricultural expansion and intensification is one of the main drivers for pollinator loss. The general aim of this work was to evaluate how ecosystem services that support agriculture were affected by agriculture intensification. To do so we analyzed, in a spatial explicit way, how habitat quality, pollination, carbon storage and soil-related ecosystem services like nutrient cycling changed in the transition of an extensive agriculture landscape to irrigated agriculture landscape, in Alentejo, Portugal. Results showed a decrease in habitat quality and crop pollination services, where irrigated areas show a lower value for these values than more natural land use types, and variation in the carbon storage, where areas of permanent irrigated crops show higher amounts of carbon stored than land uses types with annual crops. Nutrient cycling showed no significant differences between land uses. Overall, Riparian Galleries provided the highest ecosystem service capacity, while irrigated areas were the ones with the lowest capacity to provide the ecosystem services analyzed. These results allowed to evaluate the current situation in the area and therefore suggest measures to minimize the loss of some important ecosystem services, like the promotion of patches of natural vegetation surrounding areas where the ecosystem services are most needed.
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Petersen, Steven Lawrence. "A landscape-scale assessment of plant communities, hydrologic processes, and state-and-transition theory in a Western juniper dominated ecosystem." Thesis, 2004. http://hdl.handle.net/1957/29737.
Full textAbstract:
Western juniper has rapidly expanded into sagebrush steppe communities in
the Intermountain West during the past 120 years. This expansion has occurred
across a wide range of soil types and topographic positions. These plant
communities, however, are typically treated in current peer-reviewed literature
generically. The focus of this research is to investigate watershed level response to
Western juniper encroachment at multiple topographic positions.
Data collected from plots used to measure vegetation, soil moisture, and
infiltration rates show that intercanopy sites within encroached Western juniper
communities generally exhibit a significant decrease in intercanopy plant density
and cover, decreased infiltration rates, increased water sediment content, and lower
soil moisture content. High-resolution remotely sensed imagery and Geographic
Information Systems were used with these plot level measurements to characterize
and model the landscape-scale response for both biotic and abiotic components of a
Western juniper encroached ecosystem. These data and their analyses included an
inventory of plant density, plant cover, bare ground, gap distance and cover, a plant
community classification of intercanopy patches and juniper canopy cover, soil
moisture estimation, solar insulation prediction, slope and aspect. From these data,
models were built that accurately predicted shrub density and shrub cover
throughout the watershed study area, differentiated by aspect.
We propose a new model of process-based plant community dynamics
associated with current state-and-transition theory. This model is developed from
field measurements and spatially explicit information that characterize the
relationship between the matrix mountain big sagebrush plant community and
intercanopy plant community patterns occurring within a Western juniper
dominated woodland at a landscape scale. Model parameters (states, transitions,
and thresholds) are developed based on differences in shrub density and cover,
steady-state infiltration rates, water sediment content, and percent bare ground in
response to juniper competition and topographic position. Results from both
analysis of variance and multivariate hierarchical cluster analysis indicate that
states, transitions, and thresholds can be accurately predicted for intercanopy areas
occurring within the study area. In theory, this model and the GIS-based layers
produced from this research can be used together to predict states, transitions, and
thresholds for any location within the extent of the study area. This is a valuable
tool for assessing sites at risk and those that have exceeded the ability to self-repair.Graduation date: 2005
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SICA, FRANCESCO. "Ecosystem services and integrated urban systems. Multi-criteria economic analysis models and optimisation tools to support design processes." Doctoral thesis, 2021. http://hdl.handle.net/11573/1629643.
Full textAbstract:
Il tema sullo sviluppo urbano sostenibile ricopre un ruolo centrale nelle politiche urbane di molte città europee e non. Le indicazioni dei documenti programmatici dell’Organizzazione delle Nazioni Unite (ONU), dell’Unione Europea e degli Stati Membri della Comunità Europea propongono linee guida al fine di «rendere le città e gli insediamenti umani più inclusivi, sicuri, resilienti e sostenibili». Ad una prima fase in cui il dibattito sulla sostenibilità ha riguardato la necessità di fronteggiare il rapido cambiamento climatico attraverso la salvaguardia e la tutela delle componenti ambientali e naturali, a partire dagli inizi del XXI secolo è seguita una fase in cui si è avvertita la necessità di indirizzare le trasformazioni insediative delle città considerando congiuntamente, quindi in chiave ecosistemica integrata, gli aspetti relativi sia alle risorse naturali e ambientali esistenti, sia ai servizi da essi generati, con gli effetti e le ricadute di tipo economico, sociale e culturale. La Commissione Europea propone iniziative volte a migliorare lo stato delle città per mezzo di ecologically sound urban design practices utili allo sviluppo economico del territorio, al benessere della collettività e alla salvaguardia della componente naturale esistente. L’integrazione di azioni di forestazione urbana e peri-urbana con gli aspetti urbanistici, architettonici, tecnologici, impiantistici, naturalistici e ambientali del progetto può contribuire ad innalzare il livello di qualità ambientale, sociale e culturale, nonché la capacità reddituale di porzioni di territorio urbanizzato. Si tratta di benefici plurimi per la collettività da valutare in termini di servizi eco-sistemici. La possibilità di progettare interventi ricomprendenti anche la forestazione urbana, definibili come Integrated Ecosystem Urban Projects (IEUP), richiede strategie d’azione volte alla sostenibilità urbana integrata.
In questa prospettiva, s’intende proporre un protocollo di valutazione economica definito con logica multi-criteriale (integrated assessment framework). Si tratta di uno schema di analisi pluri-parametrico geo-referenziato a supporto dei meccanismi di progettazione e valutazione delle città in forza dei servizi ecosistemici generati dal verde urbano sul territorio. Il framework proposto fa da sfondo alla costruzione di modelli operativi a supporto delle decisioni di enti pubblici e/o privati all’atto di esprimere giudizi di convenienza in fase di programmazione e regolazione degli interventi per la crescita ecosistemica della città. Nello specifico, i modelli di cui vengono illustrate le componenti strutturali e metodologiche sono implementati con riguardo a contesti di analisi e di progetto differenti, rispettivamente a scala metropolitana ed urbana. Le relazioni funzionali tra obiettivi generali e specifici, indirizzi progettuali, targets e indicatori di sviluppo sostenibile di base a problemi valutativi pertinenti alla progettazione urbana ecosistemica sono costruite secondo gli stilemi della programmazione lineare propria della Ricerca Operativa. La valutazione, economica e non, dei servizi urbani ecosistemici è espletata ricorrendo ai Night-time lights data quale proxy di variabili socio-economiche ed ambientali. Nelle conclusioni si illustreranno limiti e potenzialità del integrated assessment framework, nonché dei modelli logicio-perativi proposti. Infine, si delineeranno prospettive di ricerca della tematica oggetto di tesi.
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Pereira, Filipa Maria de Abreu. "Development of an integrative approach for the characterization of ecological risk on marine transition ecosystems: the Sado Estuary as a case study." Master's thesis, 2014. http://hdl.handle.net/10362/13909.
Full textAbstract:
Estuaries and other transitional waters are complex ecosystems critically important as nursery and shelter areas for organisms. Also, humans depend on estuaries for multiple socio-economical activities such as urbanism, tourism, heavy industry, (taking advantage of shipping), fisheries and aquaculture, the development of which led to strong historical pressures, with emphasis on pollution. The degradation of estuarine environmental quality implies ecologic, economic and social prejudice, hence the importance of evaluating environmental quality through the identification of stressors and impacts. The Sado Estuary (SW Portugal) holds the characteristics of industrialized estuaries, which results in multiple adverse impacts. Still, it has recently been considered moderately contaminated. In fact, many studies were conducted in the past few years, albeit scattered due to the absence of true biomonitoring programmes. As such, there is a need to integrate the information, in order to obtain a holistic perspective of the area able to assist management and decision-making. As such, a geographical information system (GIS) was created based on sediment contamination and biomarker data collected from a decade-long time-series of publications. Four impacted and a reference areas were identified, characterized by distinct sediment contamination patterns related to different hot spots and diffuse sources of toxicants. The potential risk of sediment-bound toxicants was determined by contrasting the levels of pollutants with available sediment quality guidelines, followed by their integration through the Sediment Quality guideline Quotient (SQG-Q). The SQG-Q estimates per toxicant or class was then subjected to georreferencing and statistical analyses between the five distinct areas and seasons. Biomarker responses were integrated through the Biomarkers Consistency Indice and georreferenced as well through GIS. Overall, in spite of the multiple biological traits surveyed, the biomarker data (from several organisms) are accordant with sediment contamination. The most impacted areas were the shipyard area and adjacent industrial belt, followed by urban and agricultural grounds. It is evident that the estuary, although globally moderately impacted, is very heterogeneous and affected by a cocktail of contaminants, especially metals and polycyclic aromatic hydrocarbon. Although elements (like copper, zinc and even arsenic) may originate from the geology of the hydrographic basin of the Sado River, the majority of the remaining contaminants results from human activities. The present work revealed that the estuary should be divided into distinct biogeographic units, in order to implement effective measures to safeguard environmental quality.
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"Improving Transitional Care for Individuals with Severe Mental Illness: The Role of Narrative Repair." Doctoral diss., 2020. http://hdl.handle.net/2286/R.I.62829.
Full textAbstract:
abstract: Traditional healthcare narratives have set the stage for the care of the population with Severe Mental Illness (P-SMI). Thus far, two prevailing health strategies anchor services for mental illnesses, acute psychiatric care, and mental health, psychosocial rehabilitation. Between these, care transitions mediate PSMI’s needs and their movements from the hospital to the community and home. However, as individuals with Severe Mental Illness (i-SMI’s) leave the hospital, time is short with little opportunity to make known authentic narratives born out of self-evidence. After transitional care, maintenance treatment re-centers these individuals back into a playbook with operatives of pathology and disability and inconsistencies with the narratives on recovery and rehabilitation.
This project sought to hear i-SMI’s stories and propose how their experience can be used to create a new “counter” story of transition that empowers these individuals through a better understanding of their “space”: conceptualized here, as all that surrounds them and is dynamic and responsive to their interactions and needs. Underpinning this inquiry is a post-modernist conversation that converges on the critical perspectives in the theory of architecture, philosophy of mind, cognitive science, and the aesthetic practice of psychiatric nursing in the context of transitional care. A qualitative paradigm of narrative repair guides an ethical appraisal, “deprivation of opportunity,” and “infiltrated consciousness,” regarding relational power dynamics that are at work in healthcare master narratives.
Narrative findings of this study reveal that identity and agency come together in a personal space of safety born out of a core sense of self, belonging, and control. Space emerges within the self-narrative as physical sensibilities in the constructs of agency and safety, and as with emotional responses, metaphor and meaning can repair personal transitions.
The counterstory derived from the narrative findings reveals: Equitable relational dynamics attune social space, the physical environment, and meaning, as a response to the dismissiveness and overcontrolling health professional power. Thus, the journey toward narrative repair from the perspective of i-SMI’s uncovers a deeper counternarrative, Ecosystem of Space: the manifestation of a personal architecture for healing, making a systematic organic-space-experience for the core sense of self to transition and flourish.Dissertation/Thesis
Doctoral Dissertation Nursing and Healthcare Innovation 2020
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Masemola, Cecilia Ramakgahlele. "Remote sensing of leaf area index in Savannah grass using inversion of radiative transfer model on Landsat 8 imagery : case study Mpumalanga, South Africa." Diss., 2015. http://hdl.handle.net/10500/19734.
Full textAbstract:
Savannahs regulate an agro-ecosystem crucial for the production of domestic livestock, one of the main sources of income worldwide as well as in South African rural communities. Nevertheless, globally these ecosystem functions are threatened by intense human exploitation, inappropriate land use and environmental changes. Leaf area index (LAI) defined as one half the total green leaf area per unit ground surface area, is an inventory of the plant green leaves that defines the actual size of the interface between the vegetation and the atmosphere. Thus, LAI spatial data could serve as an indicator of rangeland productivity. Consequently, the accurate and rapid estimation of LAI is a key requirement for farmers and policy makers to devise sustainable management strategies for rangeland resources.
In this study, the main focus was to assess the utility and the accuracy of the PROSAILH radiative transfer model (RTM) to estimate LAI in the South African rangeland on the recently launched Landsat 8 sensor data. The Landsat 8 sensor has been a promising sensor for estimating grassland LAI as compared to its predecessors Landsat 5 to 7 sensors because of its increased radiometric resolution. For this purpose, two PROSAIL inversion methods and semi- empirical methods such as Normalized difference vegetation index (NDVI) were utilized to estimate LAI. The results showed that physically based approaches surpassed empirical approach with highest accuracy yielded by artificial neural network (ANN) inversion approach (RMSE=0.138), in contrast to the Look-Up Table (LUT) approach (RMSE=0.265). In conclusion, the results of this study proved that PROSAIL RTM approach on Landsat 8 data could be utilized to accurately estimate LAI at regional scale which could aid in rapid assessment and monitoring of the rangeland resources.Environmental Sciences
M. Sc. (Environmental Science)
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Knüppe, Kathrin. "Comparative case study analysis of adaptive groundwater governance and management regimes: Exploring ecosystem services in South Africa, Spain and Germany." Doctoral thesis, 2012. https://repositorium.ub.uni-osnabrueck.de/handle/urn:nbn:de:gbv:700-2012102210424.
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Our daily lives depend on the provision of services by different ecosystems in which an important contribution is made by groundwater. To balance competing demands placed on groundwater for socioeconomic and ecological benefits constitute major challenges for water managers. At the policy-science interface the ecosystem service concept represents an appropriate approach to communicate management challenges in which researchers and politicians must take into account human and biophysical characteristics as intertwined systems. This study investigated the complexity of groundwater governance, and linkages between management and corresponding effects on ecosystem services. Empirical insights were derived from case studies in South Africa, Spain and Germany. The analytical focus includes (a) the degree of vertical (multi-level) and horizontal (cross-sectoral) integration which frame crucial characteristics of an adaptive governance regime and (b) the role of formal and informal institutions governing groundwater. In doing so, an conceptual and analytical approach was applied, especially developed to support a systematic and consistent investigation of policy and management processes. Evidence highlights that higher degrees of integration: (i) opens up the political arena for environmental perspectives, (ii) increases the quality of management plans, (iii) accelerates the implementation of measurements, (iv) mitigates conflicts between different groundwater users, and (v) increases the awareness of various ecosystem services. Further the results indicate that having well-crafted institutions in place does not automatically indicate successful groundwater management in the sense of bringing about positive results for socioeconomic or ecological sustainability. This work made a significant contribution to interdisciplinary research in the field of groundwater governance and ecosystem service management that builds the foundations for improving the policy-science interface.
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Alves, Ana Sofia Rosa Santos. "Use of benthic meiofauna in evaluating marine ecosystems’ health: How useful can free-living marine nematodes be for Ecological Quality Status (EQS) assessment in transitional waters?" Doctoral thesis, 2015. http://hdl.handle.net/10316/26920.
Full textAbstract:
Tese de doutoramento em Biociências, apresentada à Faculdade de Ciências e Tecnologia da Universidade de CoimbraMeiobenthos is an important component of estuarine systems since it facilitates biomineralization of organic matter, enhances nutrient regeneration, serves as food for higher trophic levels and exhibits high sensitivity to environmental changes. Recently, the role of meiobenthos and nematodes as indicators of ecological quality and their integration in impact and monitoring studies has been valued, being essential to understand the distribution patterns of these communities. In the scope of the growing awareness of the threat human activities represent to aquatic ecosystems, there has been a development in environmental policies, mainly focused on the ecological quality assessment. Research developed in this thesis had as main objective to enhance the knowledge regarding the ecological status and functioning of estuarine systems, based on the analysis of meiobenthic and free living nematode communities, both from subtidal and intertidal habitats. The Mondego estuary (Portugal) was addressed as case study. In Chapter 1 the analysis of the ecological assessment information regarding macrofauna and nematode communities was performed in order to discern if these communities could provide a similar classification of the system. Along the estuarine gradient both macrofauna and meiofauna communities were simultaneously analyzed. The ecological status of the system was determined by the application of specific indices, with the results pointing towards a different trend regarding the analyzed communities. This comparative study showed that nematode and macrofauna provide different but complementary responses regarding environmental status, which may be explained by different response-tostress times of each benthic community. Both assemblages should be integrated in monitoring studies to grant a more accurate assessment. In Chapter 2 the analysis was focused on the spatial and temporal distribution of meiobenthos and nematode communities, aiming at determining the main structuring factors of their distribution. It was possible to validate the division of the estuarine gradient in different stretches and to verify that, at the analyzed spatial scale (the whole estuary, thus encompassing the entire estuarine Abstract 2 gradient), the effects of temporal variability were not translated in community variations, indicating that natural variability is also superimposed to the anthropogenic pressures present in some areas of the estuary. Building on the results and interpretation of the work presented in Chapter 2, a thorough analysis of the taxonomic and functional structure of the subtidal nematode communities was carried out in Chapter 3, aiming at disentangling how the taxonomic and functional characteristic vary spatially and temporally and if there would be an added benefit in combining these approaches. This study allowed for a characterization of the traits structure of nematodes to be done for the first time for the Mondego estuary. It also allowed refining the interpretation of the estuarine stretches division, emphasizing that the upstream areas present a different community composition, something that is paramount when applying management tools. Additionally, although the Biological Traits Analysis was no more powerful than the traditional taxonomic approach in detecting spatial differences, it highlighted the peculiarity of some areas in terms of their functional structure increasing the knowledge and characterization of nematode communities in the estuary. Finally, in Chapter 4, following an eutrophication mitigation measure applied in the South arm of the Mondego estuary, the response of intertidal meiofauna and nematode communities was assessed. At this small spatial scale (polyhaline stretch), the seasonal effects were superimposed to the spatial ones, not allowing discerning communities from areas where eutrophication symptoms are known to be different. Furthermore, it allowed the recognition of the impact of climatic events over meiobenthic communities. A general discussion is also presented, integrating a synthesis of the thesis contributions to the knowledge on the use of meiobenthos and particularly free living nematodes to assess the ecological status and functioning of estuarine systems, and suggesting future research questions, challenges and paths.
As comunidades de meiofauna e nemátodes têm um papel muito importante nos ecossistemas, estando envolvidas em processos de biomineralização de matéria orgânica, de regeneração de nutrientes, servindo de alimento para níveis tróficos superiores e exibindo uma elevada sensibilidade a perturbações ambientais. Recentemente o seu papel como indicador de qualidade ecológica e a sua integração em estudos de monitorização e impacto ambiental têm sido valorizados, sendo por isso essencial conhecer os padrões de distribuição das comunidades. No contexto da crescente consciência da ameaça que as atividades humanas representam para os ecossistemas aquáticos, tem havido uma evolução nas políticas ambientais para se focarem principalmente na avaliação de qualidade ecológica. O trabalho de investigação desenvolvido nesta tese teve como principal objetivo aumentar o conhecimento do estado ecológico e funcionamento de sistemas estuarinos com base na análise das comunidades de meiofauna e nemátodes de vida livre, tanto em habitats subtidais como intertidais. O estuário do Mondego (Portugal) foi usado como caso de estudo. No Capítulo 1 avaliou-se se as comunidades de macrofauna e nemátodes fornecem informação ecológica semelhante sobre o sistema. Ao longo do estuário do Mondego analisou-se, em simultâneo, comunidades de macroinvertebrados e meiofauna, com especial ênfase em nemátodes. Aplicando índices desenvolvidos para cada comunidade que visam analisar o estado ecológico do sistema, verificouse que a informação fornecida pelas comunidades não seguia a mesma tendência. De facto, este estudo comparativo mostrou que macrofauna e meiofauna podem fornecer informação diferente mas complementar, uma vez que apresentam também diferentes tempos de resposta a perturbações, sendo aconselhado o seu uso complementar em estudos de monitorização. O Capítulo 2 focou-se na análise da distribuição espacial e temporal de meiofauna e nemátodes ao longo do estuário do Mondego, com o objetivo de identificar os principais fatores ambientais relacionados com a sua distribuição. Verificou-se que o gradiente estuarino foi seguido pelas comunidades, não se Resumo 4 verificando, à escala espacial da análise, um efeito da variabilidade temporal sobre as mesmas. Este estudo evidenciou também o efeito da variabilidade natural sobre as pressões antropogénicas presentes no estuário. Com base nos resultados do Capítulo 2, foi feita uma análise das características taxonómicas e funcionais das comunidades de nemátodes no Capítulo 3, aprofundando o seu conhecimento e analisando a sua distribuição espacial e temporal. Com este estudo foi feita uma análise das características (“traits”) de nematódes pela primeira vez para o estuário do Mondego. Foi possível aprimorar a interpretação da divisão em diferentes áreas do estuário, com especial destaque para as áreas a montante, sendo esta informação útil quando se aplicam ferramentas de gestão. Além disso, embora a análise de características biológicas não tenha sido mais poderosa do que a abordagem taxonómica na deteção de diferenças espaciais, evidenciou a peculiaridade de algumas áreas em termos da sua estrutura funcional, aumentando o conhecimento e caracterização das comunidades de nematódes no estuário. Por fim, no Capítulo 4, analisou-se a resposta das comunidades intertidais de meiofauna e nemátodes após a aplicação de uma medida de mitigação no Braço Sul do estuário do Mondego. À pequena escala espacial da análise (área polihalina) os efeitos da sazonalidade foram sentidos, com variações na comunidade, não permitindo distinguir claramente as comunidades de nemátodes ao longo do gradiente de eutrofização. Foi também possível confirmar o impacto de eventos climáticos na estrutura das comunidades. A secção final de discussão geral integra e discute o uso das comunidades meiobentónicas para a avaliação do estado ecológico e funcionamento de sistemas estuarinos. Na sequência dos estudos feitos são também sugeridas novas abordagens e futuros desafios com vista a aumentar o conhecimento científico sobre estas comunidades e sua aplicação.
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Marques, José Luís Clemente. "Microplastics in the Mondego Estuary and adjacent coastline: Occurrence, characterisation and associated bacterial communities." Master's thesis, 2021. http://hdl.handle.net/10316/97953.
Full textAbstract:
Dissertação de Mestrado em Bioquímica apresentada à Faculdade de Ciências e TecnologiaA contaminação por microplásticos (<5 mm) é considerada hoje em dia como ubíqua no ambiente e mesmo num cenário futuro extremamente ambicioso (sem mais emissões) irá continuar a aumentar. Assim, é importante avaliar os potenciais riscos e consequências ecológicas que possam advir não só dos níveis atuais de contaminação ambiental por microplásticos, como também em possíveis cenários futuros. Uma das preocupações atuais está relacionada com a possibilidade dos microplásticos abrigarem comunidades bacterianas diferentes das encontradas nos seus ambientes e o potencial para estas partículas atuarem como vetores de transmissão e propagação de grupos bacterianos chave, como agentes patogénicos. No entanto, apenas um número relativamente baixo de estudos investigou a natureza das comunidades bacterianas associadas aos microplásticos, a chamada “Plastisfera”, em ecossistemas de transição costeiros, como praias arenosas ou áreas estuarinas. Tendo isto em conta, foram realizadas duas campanhas de amostragem em dois ecossistemas de transição de Novembro a Dezembro de 2020 onde foram recolhidas amostras de água do estuário do Mondego e de areias da linha costeira adjacente (Figueira da Foz, Portugal) para a análise de microplásticos. Após a extração manual das partículas em condições estéreis, a extração de DNA e a sequenciação do gene 16SrRNA por amplicon high throughput foi utilizado para traçar o perfil das comunidades bacterianas da superfície dos microplásticos e das encontradas nas amostras de água e sedimentos dos ecossistemas de transição. Todas as partículas foram caracterizadas de acordo com o tipo, cor e tamanho e a natureza química das partículas foi inspecionada por espectroscopia μ-FTIR após a extração do DNA.Foram isoladas um total de 89 partículas, a maioria dos microplásticos extraídos do ambiente estuarino foram fibras (87%) e foram identificadas como fibras de Poliacrilonitrilo (PAN) e de Polipropileno (PP), enquanto no ambiente de praia a maioria dos microplásticos foram classificados como fragmentos e espumas (85%) e identificados como microplásticos de Polietileno (PE) e de Poliestireno (PS). Apesar de não terem sido detetadas diferenças significativas entre as comunidades bacterianas e os índices de diversidade α dos microplásticos e dos seus ambientes circundantes, a análise dos dados e da estrutura das comunidades mostraram a ocorrência e abundância de géneros bacterianos tipicamente marinhos nos microplásticos estuarinos que eram escassos ou ausentes das águas estuarinas. Foi ainda identificada uma maior proximidade entre as comunidades bacterianas dos microplásticos estuarinos e as amostras das praias do que com as águas estuarinas. Estas observações sugerem a existência de uma contribuição substancial da trajetória mar-rio para a contaminação global por microplásticos nos estuários. Para além disso, foi também observada a ocorrência e uma maior abundância de grupos bacterianos únicos em microplásticos, tais como agentes patogénicos (p.e. Pseudoalteromonas, Flavobacterium, Lactococcus, Staphylococcus, Acinetobacter, Mycobacterium, e Shewanella). A presença destes membros pode sugerir uma origem de estações de tratamento de águas residuais ou de esgotos, mas serão necessários mais estudos para avaliar esta possibilidade. Estes resultados sublinham a possibilidade de estas partículas poderem atuar como vetores de transmissão e disseminação em ecossistemas de transição. Este estudo revela também a importância do estudo das comunidades bacterianas associadas a microplásticos na compreensão da contaminação ambiental por microplásticos. Apesar de proporcionar novas perspetivas serão necessários mais estudos para aumentar a compreensão sobre este tópico científico recente.
Microplastic (<5 mm) contamination is considered nowadays ubiquitous in the environment and even in an extremely ambitious future scenario (with no further emissions) will continue to increase. Therefore, it is important to evaluate the potential ecological risks and consequences that might outcome not only for today’s environmental microplastic contamination levels but also for possible future levels. One of the current concerns is related to the possibility of microplastics harbour different bacterial communities than those found in their environment and the potential for these particles to act as vectors of transmission and spread of key bacterial groups, such as pathogens. Yet, a relatively low number of studies have investigated the nature of microplastics associated bacterial communities, the so-called “Plastisphere”, in transitional coastal ecosystems, such as sandy beaches or estuarine areas. Taken that into account, two sampling campaign events were conducted in two transitional ecosystems in November-December 2020. Samples of water samples on the Mondego estuary and sand samples on its adjacent coastline were (Figueira da Foz, Portugal) collected for microplastic analysis. After manual sorting of particles under sterile conditions, DNA extraction and 16S rRNA amplicon high throughput sequencing was used to profile the bacterial communities on the surface of microplastics and from those found on the samples of water and sediments from the transitional ecosystems. All particles were characterised according to type, colour and size, and the chemical nature of the particles was inspected by μ-FTIR spectroscopy after DNA extraction.A total of 89 particles were isolated and the majority of microplastics extracted from the estuarine environment were fibres (87%) and were identified as Polyacrylonitrile (PAN) and polypropylene (PP), while on the beach environment the majority of microplastics were fragments and foams (85%) and were identified as Polyethylene (PE) and Polystyrene (PS) microplastics. Although no significant differences were detected between the bacterial communities from distinct samples and between the α-diversity indexes from microplastics and their surrounding environments, data and community structure analyses showed the occurrence and abundance of typical marine-associated bacterial genera on estuarine microplastics that were scarce or absent from estuarine waters. Overall, the bacterial communities in the estuarine microplastics were more related to the beach samples than with the estuarine waters. These observations suggest the existence of a substantial contribution of a sea-river trajectory to the overall estuarine microplastic contamination. Furthermore, it was also observed the occurrence of unique and higher abundance of key bacterial groups on microplastics, such as pathogens (e.g., Pseudoalteromonas, Flavobacterium, Lactococcus, Staphylococcus, Acinetobacter, Mycobacterium, or Shewanella). The presence of these members might suggest a wastewater treatment plant (WWTP) or sewage origin but further research is required to assess this possibility. These results highlight the concern for these particles to act as vectors of transmission and spread in transitional ecosystems. This study also highlights the importance of the study of microplastic-associated bacterial communities to the comprehension of microplastic environmental contamination. Although this study provides new insights into this recent scientific topic, further research will be required to increase our understanding of these topics.
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Morgan, Leona. "Chroniese moegheidsindroom : 'n ekosistemiese perspektief." Diss., 1996. http://hdl.handle.net/10500/17513.
Full textAbstract:
Hierdie studie is 'n kwalitatiewe ekosistemiese ondersoek van die fenomeen Chroniese Moegheidsindroom (CMS) . Die paradigmaverskuiwing vanaf die Cartesiaans-Newtoniaanse epistemologie na die kubernetiese epistemologie, het 'n aantal belangrike implikasies vir die bestudering en konseptualisering van CMS, soos uiteengesit in hierdie studie.
'n Bespreking van die konseptualisering en behandeling van CMS
vanuit die tradisionele, reduksionistiese navorsing word verskaf.
Die aannames van twee-orde kubernetika en sosiale konstruksionisme,
is bespreek en toegepas op die beskrywing van twee sisteme waarin
CMS voorkom. Die navorsingsmetodologie van die studie is gegenereer
op grand van die genoemde teoretiese aannames. Die implikasies van die toepassing van die ekosistemiese epistemologie vir die konseptualisering van CMS word uitgewys. Die herkonseptualisering van CMS as 'n transisieproses word bespreek en riglyne vir verdere navorsing en psigoterapie word aangedui. Die huidige studie bied 'n beskrywing van die unieke betekenisse en oplossings wat gesinne genereer tydens die veranderings wat CMS vergesel.The present study is a qualitative ecosystemic exploration of the phenomenon known as chronic fatigue syndrome (CFS). The paradigm shift from the Newtonian epistemology to the epistemology of cybernetics, has important implication for research and the conceptualisation of CFS, as indicated in the study. The traditional, reductionist conceptualisation of CFS in research and treatment methods, is discussed. The suppositions of second order cybernetics and social constructionism, are discussed and applied in the description of two systems where CFS occurs. The research methodology of the present study is generated from the theoretical suppositions. Die implications of the use of the ecosystemic epistemology for the conceptualisation of CFS are indicated. The re-conceptualisation of CFS as a transition process is discussed and guidelines are given for future research and psychotherapy. The present study is a description of the unique meanings and solutions that the families generated during the changes that accompany CFS.
Psychology
M.A. (Kliniese Sielkunde)
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Μουζακίτης, Γιάννης. "Περί συστημικών παρεμβάσεων σε αειφόρα βιομηχανικά οικοσυστήματα υπό το πρίσμα της κοινωνικοτεχνικής προσέγγισης." Thesis, 2008. http://nemertes.lis.upatras.gr/jspui/handle/10889/1537.
Full textAbstract:
Η ανάπτυξη βιομηχανικών οικοσυστημάτων αποτελεί τη βασική κατεύθυνση της βιομηχανικής οικολογίας, η οποία προβάλλει ως ένα από τα πλέον ολοκληρωμένα μοντέλα αειφόρου ανάπτυξης. Η διδακτορική διατριβή αφορά στις συστημικές παρεμβάσεις που απαιτούνται για τη δημιουργία, συντήρηση και ανάπτυξη βιομηχανικών οικοσυστημάτων ή τεχνολογικών θυλάκων όπως ορίζονται υπό το πρίσμα της κοινωνικοτεχνικής προσέγγισης. Προς αυτήν την κατεύθυνση, η εργασία αποτελεί μια καινοτόμο προσπάθεια, η οποία εστιάζει (σε μίκρο και μάκρο επίπεδο) στα προβλήματα που εμφανίζονται και στις παρεμβάσεις που απαιτούνται κατά τη μετάβαση προς ένα νέο οικοβιομηχανικό τεχνολογικό καθεστώς. H διατριβή στοχεύει κυρίως στη παραγωγή θεωρίας και καθοδηγητικών πλαισίων σχετικά με τη διαδικασία μετάβασης προς το οικοβιομηχανικό παράδειγμα μέσω δευτερογενούς ανάλυσης υφιστάμενων περιπτώσεων και εφαρμογής θεωρητικών εργαλείων από τα πεδία της συστημικής επιστήμης και των σπουδών τεχνολογίας και επιστήμης.
Αρχικά, το βιομηχανικό οικοσύστημα αντιμετωπίζεται ως σύστημα, δηλαδή ως σύνολο μερών τα οποία παρουσιάζουν αναδυόμενες ιδιότητες, και αναλύεται με τη βοήθεια θεμελιωδών συστημικών χαρακτηριστικών. Στη συνέχεια, το βιομηχανικό οικοσύστημα αντιμετωπίζεται ως οργάνωση, δηλαδή ως μια συγκροτημένη ομάδα εμπλεκομένων που στοχεύουν στην πραγμάτωση συγκεκριμένων στόχων, και αναλύονται τα προβλήματα που ανακύπτουν κατά το σχεδιασμό και την υλοποίηση των απαιτούμενων παρεμβάσεων. Τέλος, σε μια συνθετική οπτική, το βιομηχανικό οικοσύστημα αντιμετωπίζεται ως ένα νέο τεχνολογικό καθεστώς, δηλαδή ως ένα σύνολο πεποιθήσεων, κανόνων και τεχνολογιών που ρυθμίζει και διαμορφώνει τη βιομηχανική δραστηριότητα, και εξετάζεται η μετάβαση προς ένα οικοβιομηχανικό σύστημα παραγωγής, υπό το πρίσμα της κοινωνικοτεχνικής προσέγγισης, μέσω συστημικών παρεμβάσεων σε σχετικούς τεχνολογικούς θύλακες.
Στη διατριβή προτείνονται ερμηνευτικά και καθοδηγητικά πλαίσια, τα οποία σε μίκρο επίπεδο μπορούν να εφαρμοσθούν στη διαχείριση και ανάπτυξη υφιστάμενων βιομηχανικών οικοσυστημάτων, ενώ σε μάκρο επίπεδο, μπορούν να χρησιμοποιηθούν στη χάραξη στρατηγικών πολιτικών οικοβιομηχανικής ανάπτυξης.This thesis concerns the systemic interventions required for the development, maintenance and diffusion of industrial ecosystems managed as technological niches under the prism of the socio-technical approach. Towards this end, it is an innovative effort that concentrates on the issues emerged and on the interventions required in the transistion towards a novel eco-industrial technological regime. The main contribution of the research reported is the development οf theoretical constructs, as well as a normative framework for the transition process towards an eco-industrial paradigm. Methodologically, the analysis was based on a secondary research approach and application of theoretical tools from the disciplines of Systems Science and Science and Technology Studies. Initially, the industrial ecosystem was considered as a system and was analysed through fundamental systems concepts. Following, it was approached as an organization, and the associated problems of its transition process were analyzed. Finally, towards a more synthetic view, industrial ecosystems were considered as the constituent parts of a novel socio-technical regime of productions systems. The transition towards such an eco-industrial regime was analyzed through systemic interventions in technological niches by reference to existing industrial ecosystems. The thesis proposes explanatory and prescriptive frameworks for the design of the necessary interventions. At a micro level, the frameworks developed can be applied to the management and further development of existing industrial ecosystems, while at a macro level, they can be used by policy makers in the development of strategies aiming at the diffusion of the eco-industrial paradigm.
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Schnetzer, Julia Ruth. "Food and sustainability: the sustainable food system index." Master's thesis, 2018. http://hdl.handle.net/10071/17265.
Full textAbstract:
Sustainable transitions have become the guiding principles of today’s century with food systems at
the core of it. Food and nutrition illustrate a basic human need, inevitable for any living organism, and
deeply entangled within the ecosystem. Thus, food systems represent predominant endeavours when
aiming towards Agenda 2030. In line with displaying complex socio-ecological processes, heavily affected by ongoing interrelations among human and natural components, three categories identify as crucial for sustainable food systems – food security, ecosystem stability and resilience and sociocultural
wellbeing. In combination with the research aim of assessing the sustainability degree of performing
food systems in place, a Sustainable Food System Index (SFSI) has been established. The SFSI measures
food system sustainability across 33 countries among 3 categories and 9 dimensions by employing 39
indicators, 65 sub-indicators and 38 sub-sub-indicators. The results display the varying degree of sustainable food systems among performing countries across selected indicators. The overall index score
highlights Sweden as the front runner, closely followed by France and the United Kingdom, while laggards illustrate Ethiopia, Nigeria and India. With food systems being caught in a vicious circle with the
ecosystem and the environment, economically poor regions are particularly vulnerable due to its smallholder dependency on agricultural systems. The SFSI outcomes provide more insights into the sustainability’s state of analysed food systems in the categories of food safety, ecosystem stability and resilience, as well as sociocultural wellbeing and might serve as foundation for future sustainable food system
research.Transições sustentáveis têm se tornado os princípios orientadores do século de hoje, com sistemas alimentares em seu núcleo. Alimentação e nutrição ilustram uma necessidade humana básica, inevitável para qualquer organismo vivo e, profundamente entrelaçada com o ecossistema. Assim, sistemas alimentares representam esforços predominantes ao focar na Agenda 2030. Em consonância com a apresentação de processos socio-ecológicos complexos, fortemente afetados por interrelações entre componentes naturais e humanos em curso, três categorias identificam-se como essenciais aos sistemas alimentares sustentáveis: segurança alimentar, estabilidade e resiliência do ecossistema, e bem-estar sociocultural. Em combinação com o objetivo da pesquisa de avaliar o grau de desempenho de sustentabilidade de sistemas alimentares decorrentes, foi criado um Índice de Sistema Alimentar Sustentável (SAS). O SAS mede a sustentabilidade do sistema alimentar em 33 países dentro de 3 categorias e 9 dimensões ao empregar 39 indicadores, 65 sub-indicadores e 38 sub-sub indicadores. Os resultados mostram o grau variável de sistemas alimentares sustentáveis entre países nos indicadores selecionados. O resultado geral do índice destaca a Suécia como líder, seguida de perto por França e Reino Unido, enquanto como retardatários ilustram Etiópia, Nigéria e Índia. Com sistemas alimentares sendo apanhados em círculos viciosos com o ecossistema e meio-ambiente, regiões economicamente pobres são particularmente vulneráveis devido a suas baixas dependências em sistemas de agricultura. Os resultados do SAS fornecem mais insights no estado da sustentabilidade dos sistemas alimentares analisados nas categorias de segurança alimentar, estabilidade e resiliência do ecossistema, tanto quanto de bem-estar sociocultural e, deve servir como fundação para futuras pesquisas sobre sistema alimentar sustentável.