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Modélisation de la dynamique des systèmes de peuplement : de SimpopLocal à SimpopNet / Modeling settlements systems dynamics : from SimpopLocal to SimpopNetSchmitt, Clara 28 February 2014 (has links)
L'évolution des villes est-elle le résultat de leurs multiples interactions ? C'est sur ce postulat que s'appuie la théorie évolutive urbaine (Pumain, 2000) pour analyser les processus de croissance des villes. Cette thèse, réalisée dans un contexte inter-disciplinaire, vise à évaluer la validité d'une telle hypothèse par la simulation informatique. Pour mener à bien ce projet, les savoirs accumulés sur la dynamique des systèmes de villes sont d'abord rassemblés afin d'en extraire les grandes caractéristiques, synthétisées sous la forme de dix fait stylisés majeurs. Deux modèles de simulation, SimpopLocal et SimpopNet, sont ensuite construits, documentés de manière standardisée, et explorés de manière systématique. Ces modèles interrogent chacun un aspect précis de la théorie évolutive urbaine: la nature des interactions interurbaines pour le premier et leur support pour le second. Les besoins associés à leur nécessaire évaluation ont guidé la conception et la mise en œuvre de deux protocoles d'explorations systématiques inédits: une méthode de calibrage automatisée, et un protocole d'analyse de sensibilité qui évalue individuellement la contribution de chaque mécanisme aux comportements simulés. Ces deux formes d'exploration confrontent de façon systématique les résultats de simulation avec les connaissances actuelles. Elles montrent que ces modèles sont capables de rendre compte de processus clés de la dynamique des systèmes des villes et prouvent pour la première fois la nécessité de mécanismes d'interactions interurbaines pour simuler des croissances proches des évolutions de systèmes réels. / Is urban growth the result of multiple interactions between cities ? Urban evolutionary theory (Pu main, 2000), based on this postulate, analyses urban growth processes. This thesis, undertaken in an inter-disciplinary context, aims to evaluate the validity of the hypothesis by means of computer simulation. Strong regularities of the urban systems dynamics are extracted from the accumulated scientific knowledge and synthetized into ten major stylized facts. Two simulation models, SimpopLocal and SimpopNet, are then built, documented - thanks to a standardized grid - and systematically explored. They each question a specific aspect of the urban evolutionary theory : the nature of the inter-urban interactions for the first model (i.e. competition for innovation) and their support for the second model (i.e. the role of the communication network structure). The evaluation of the two models required the design and the implementation of two original exploration protocols : an automated calibration method and a sensibility analysis protocol (the Exploration Profile algorithm) which individually evaluates the contribution of each implemented mechanism to the simulated behavior. These two forms of exploration systematically confront the simulation results with current scientific knowledge. They indicate that the two models are able to account for key processes of urban systems dynamics, such as their hierarchical organization, and demonstrate for the first time the need for interurban interaction mechanisms in order to simulate urban evolutions that are close to those observed on real urban systems.
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A structural analysis of neighborhood and school effects on immigrant children's academic performanceZha, Peijia, January 2009 (has links)
Thesis (Ph. D.)--Rutgers University, 2009. / "Graduate Program in Urban Systems." Includes bibliographical references (p. 154-168).
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An analysis of the effects of traditional versus alternative educational assessment programs on student attitudes and post secondary outcomesKeeton, Vincent André, January 2010 (has links)
Thesis (Ph. D.)--Rutgers University, 2010. / "Graduate Program in Urban Systems." Includes bibliographical references (p. 224-233).
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An assessment of urban residents' knowledge and appreciation of the intangible benefits of trees in two medium sized towns in South AfricaChinyimba, Abby January 2013 (has links)
In order to meet the different public needs and requirements of contemporary urban society, a better understanding of public perceptions, appreciation and knowledge of the assorted values derived from urban trees is beneficial for improved urban greening. Thus, this study carried out an assessment of urban residents’ knowledge and appreciation of the benefits of trees and the role they play in enhancing the quality of life in urban systems. The study primarily focused on the intangible benefits (also referred to as cultural and regulating services) of urban trees, because most research to date in South Africa on trees and the benefits derived from them is biased towards the provisioning services of trees in rural areas. The significance and contribution of the intangible benefits of trees in urban systems is often underestimated and not seriously taken into account by urban planners, policy makers and other key decision makers. The study was conducted in three different residential settlement types (formal townships, RDP settlements and informal settlements) in two towns in the Limpopo Province in South Africa, namely Bela-Bela and Tzaneen. Findings revealed that the intangible benefits of trees are seen to play a significant role in improving both residents’ quality of life and the environmental conditions in cities, including the preservation of biodiversity. Findings also showed that urban residents had strong spiritual connections with trees and placed considerable cultural and historical importance on specific tree species and individual trees. Urban residents in both towns had moderate knowledge of the intangible benefits of trees based on the knowledge score that was created for the purposes of this study. Fifty seven percent of the residents had ‘reasonable’ knowledge of some of the intangible benefits of trees, while 43% had low levels of knowledge. That said, the majority of residents demonstrated high appreciation (98%) of the intangible benefits of trees (especially social and cultural values), with few residents not recognising these, suggesting that knowledge does not necessarily lead to appreciation. Age and level of education were found to influence knowledge of the intangible benefits of trees. A large proportion (86%) of residents who possessed tertiary level qualifications had more knowledge of the intangible benefits of trees as compared to residents with no formal education. Findings also revealed that younger respondents (60%) had more knowledge of the intangible benefits of trees. Factors that influenced appreciation of the intangible benefits of trees included links to crime, peoples’ value systems (their pro-environmental and altruistic values) and residential settlement type. Sixty five percent of residents in both towns felt that urban street trees and trees in public spaces attract criminals and promote crime, while 67% of RDP and 96% of informal township residents did not use or appreciate the social and recreational benefits of trees mainly because of the absence or long distances to public parks. A Willingness To Pay (WTP) survey revealed that a high proportion of residents in Bela-Bela (86%) were WTP a small annual fee in order to sustain greening initiatives in their communities compared to the residents in Tzaneen (53%). In terms of the planting and retention of trees, it was found that 300 households in both study towns had planted and retained a total of 1 615 trees in spite of the various factors that negatively influenced planting and retention of trees such as residency time and tenure security. The majority (66%) of informal township residents said tenure security was an important factor to consider when making tree planting decisions, while this was not an issue for formal township and RDP residents. Policy implications and recommendations are presented to help municipalities and urban planners improve and develop effective policies and programmes that will enable implementation of sustainable urban greening programmes
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Resilience of Coupled Urban Socio-Physical Systems to Disasters: Data-Driven Modeling ApproachTakahiro Yabe (11186277) 26 July 2021 (has links)
<div>Cities face significant challenges in developing urban infrastructure systems in an inclusive, resilient, and sustainable manner, with rapid urbanization and increasing frequency of shocks (e.g., climate hazards, epidemics). The complex and dynamic interdependencies among urban social, technical, institutional, and natural components could cause disruptions to cascade across systems, and lead to heterogeneous recovery outcomes across communities and regions. Large scale data collected from mobile devices, including mobile phone GPS data, web search data, and social media data, allow us to observe urban dynamics before, during, and after disaster events in an unprecedented spatial-temporal granularity and scale. Despite these opportunities, we lack data-driven methods to understand the underlying mechanisms that govern the recovery and resilience of cities to shocks.</div><div>Such dynamical models, in contrast to static index based metrics of resilience, will allow us to test the effects of policies on the heterogeneous post-disaster recovery trajectories across space and time. </div><div><br></div><div>In this dissertation, I studied the recovery dynamics and resilience of urban systems to disasters using a large-scale human-centered data-driven modeling approach, with particular emphasis on the complex interdependencies among social, economic, and infrastructure systems. First, statistical analysis of large-scale human mobility data collected from over 1 million mobile phone devices in five major disaster events across the globe, revealed universal population recovery processes across regions and disasters, including disproportionate disaster effects based on income inequalities and urban-rural divide. Second, human mobility data are used to infer the recovery of various socio-economic systems after disasters. Using Bayesian causal inference models, regional and business sectoral inequalities in disaster recovery are quantified. Finally, the analysis on social, economic, and physical recovery were integrated into a dynamical model of coupled urban systems, which captures the bi-directional interdependencies among socio-economic and physical infrastructure systems during disaster recovery. Using the model and data collected from Puerto Rico during Hurricane Maria, a trade-off relationship in urban development is revealed, where developed cities with robust centralized infrastructure systems have higher recovery efficiency of critical services, however, have socio-economic networks with lower self-reliance during crises, which lead to loss of community resilience. Managing and balancing the socio-economic self-reliance alongside physical infrastructure robustness is key to resilience. </div><div><br></div><div>The proposed models and results presented in this dissertation lay the scientific foundations of urban complexity and resilience, encouraging us to move towards dynamical and complex systems modeling approaches, from conventional static index-based resilience metrics. Big data-driven, dynamical complex systems modeling approaches enable quantitative understanding of the underlying disaster recovery process (e.g., interdependencies, feedbacks, cascading effects) across large spatial and temporal time scales. The approach is capable of proposing community-based policies for urban resilience via cross-regional comparisons and counterfactual scenario testing of various policy levers. </div>
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Infrastructure ecology of urban natural gas systemsWright, Jessica Lynn 07 February 2024 (has links)
As climate change continues to intensify, growing interest in equitable clean energy transition has emerged to address the environmental and public health impacts of aging energy infrastructure. Of special concern is aging natural gas infrastructure, which serves as a significant source of the potent greenhouse gas (GHG) methane (CH4) and poses risk to the health and safety of the public. The concentration of aging natural gas distribution pipelines in urban centers has motivated this research, examining dynamic interactions among natural gas distribution pipelines, street tree canopies, and local climate action plans. This dissertation approaches the study of urban natural gas systems using an infrastructure ecology framework – a framework to investigate the dynamic relationships among elements of built, natural, and social infrastructure.
The results of three studies reported below aim to improve our knowledge of the environmental impacts of aging natural gas infrastructure in urban centers and examine policy opportunities for a clean energy transition. Using a temporal and spatial dataset of street tree condition and soil CH4 and oxygen concentrations across Brookline, MA we were able to model the impact of CH4 on the success of a street tree using the spatial Durbin model. We find that persistent exposure to CH4 and diminished oxygen in the soil pit is correlated with poor tree condition.
Next, utilizing a novel virtual data collection application, we tracked the location of leak-prone natural gas distribution infrastructure along the streets of Chelsea, MA. By producing and combining this unique dataset with the comprehensive street tree inventory completed by the municipality, we examined for the first time the relationship between street tree condition and proximity to leak-prone distribution pipe. Results from this analysis were suggestive and demonstrated a need for more comprehensive spatial data collection using virtual tools that can detect dynamic changes in the infrastructure to explain phenomena we are not yet able to interpret. Findings suggest the importance of considering the location of leak-prone pipelines when planting new street trees and protecting existing mature trees.
Finally, we introduce the term and conceptual framework ‘infrastructure biome’ to define and describe the interconnected and dependent built, social, and natural infrastructure systems that extend beyond jurisdictional borders. We propose that energy transition policy, specifically a transition off natural gas, would benefit from a regional collaborative policy to achieve the ambitious climate action goals of cities and states throughout the region. Using publicly available natural gas pipeline data, we examine aging and leak-prone natural gas infrastructure for the first time at a regional scale and recommend a collaborative policy to address the shared obstacle of aging natural gas infrastructure to achieve climate action goals.
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Urban shades of green : Current patterns and future prospects of nature conservation in urban landscapesBorgström, Sara January 2011 (has links)
Urban nature provides local ecosystem services such as absorption of air pollutants, reduction of noise, and provision of places for recreation, and is therefore crucial to urban sustainable development. Nature conservation in cities is also part of the global effort to halt biodiversity decline. Urban landscapes, however, display distinguishing social and ecological characteristics and therefore the implementation of nature conservation frameworks into cities, requires reconsideration of what nature to preserve, for whom and where. The aim of this thesis was to examine the current urban nature conservation with special focus on formally protected areas, and discuss their future role in the urban landscape. A social-ecological systems approach was used as framework and both quantitative and qualitative methods were applied. The studies were performed at local to regional scales in the southern part of Sweden. Four key questions were addressed: i) What are the characteristics of nature conservation in urban landscapes? ii) How does establishment of nature conservation areas affect the surrounding urban landscape? iii) In what ways are spatial and temporal scales recognized in practical management of nature conservation areas? and iv) How can the dichotomy of built up and nature conservation areas be overcome in urban planning? Nature reserves in urban, compared to rural landscapes were in general fewer, but larger and included a higher diversity of land covers. They were also based on a higher number and different kinds of objectives than rural nature reserves. Urbanisation adjacent to nature reserves followed the general urbanisation patterns in the cities and no additional increase in urban settlements could be detected. In general, there was a lack of social and ecological linkages between the nature conservation areas and the urban landscape and practical management showed a limited recognition of cross-scale interactions and meso-scales. Such conceptual and physical isolation risks decreasing the public support for nature conservation, cause biodiversity decline, and hence impact the generation of ecosystem services. A major future challenge is therefore to transform current conservation strategies to become a tool where urban nature is perceived, planned and managed as valuable and integrated parts of the city. To enable social-ecological synergies, future urban planning should address proactive approaches together with key components like active enhancement of multifunctional landscapes, cross-scale strategies and border zone management. / <p>At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 2: Manuscript. Paper 3: Submitted. Paper 5: Manuscript.</p>
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Enrichment of functional analysis for the construction sector by the integration of systems engineering and constructibility : application to the multifunctional metro / Enrichissement de l'Analyse Fonctionnelle pour le secteur de la construction par l'intégration de l'ingénierie système et de la constructibilité : application au métro multifonctionnelZiv, Nicolas 29 November 2018 (has links)
L’objectif de la thèse est d’enrichir l’Analyse Fonctionnelle, une méthode de conception orientée sur la définition des fonctions d’un produit, pour le développement d’ouvrages complexes dans le domaine de la construction. Pour cela les concepts et pratiques de deux corpus méthodologiques sont adaptés et intégrés dans l’Analyse Fonctionnelle : l’Ingénierie Système et la Constructibilité. Cette méthode enrichie est appliquée sur un concept innovant de métro multifonctionnel qui consiste à utiliser un système unique pour répondre à plusieurs besoins de la ville : non seulement transporter des passagers mais aussi de l’eau, des déchets, de l’électricité, de la chaleur, de l’information, des marchandises et bien d’autres selon les particularités de chaque projet. Dans l’introduction après avoir brièvement décrit les enjeux rencontrés dans le domaine de la construction, qui justifient le besoin de nouvelles méthodes, nous soulignons que l’Analyse Fonctionnelle a essentiellement été utilisée dans d’autres domaines que celui de la construction pour faire face aux mêmes problèmes. En revanche, son application au domaine de la construction est limitée du fait de la non prise en compte des particularités de ce secteur : le besoin auquel répondent les systèmes dans ce domaine sont d’adapter l’espace pour que s’y réalise des activités humaines, mais aussi que chaque projet est unique. L’unicité de chaque projet nous a amené à prendre en compte la constructibilité, soit les contraintes liées au développement de l’ouvrage, à différentes étapes de l’Analyse Fonctionnelle. L’Analyse Fonctionnelle est aussi mal adaptée pour le développement de systèmes complexes, ainsi, les concepts et outils de l’ingénierie Système, dont l’objectif est la maitrise des systèmes complexes, sont intégrés à l’Analyse Fonctionnelle (V&V, SysML). La première partie de la thèse consiste en un état de l’art des trois méthodes étudiées : l’Analyse Fonctionnelle, l’Ingénierie Système et la Constructibilité. Dans cette partie les blocages et des adaptations nécessaires sont identifiés. Dans une deuxième partie, la méthode d’Analyse Fonctionnelle enrichie par la Constructibilité et l’Ingénierie Système est présentée. Le concept de Constructibilité notamment est étendu à la prise en compte non seulement des contraintes liées aux activités de réalisation mais aussi aux contraintes de conception et de planification/programmation (soit l’ensemble du système pour faire). L’Ingénierie Système pour sa part est adaptée en prenant en compte les caractéristiques spatiales des systèmes, composantes essentielles dans la construction. Deux outils ont été développés pendant la thèse permettant d’implémenter la méthode : un outil de modélisation des exigences basé sur le langage de modélisation SysML qui permet de lier les exigences avec des modèles BIM (Building Information Modeling) améliorant ainsi leur traçabilité et la facilitation de leur vérification, et la matrice de constructibilité qui permet d’analyser la constructibilité d’un système en prenant en compte l’ensemble des contraintes liées à son développement. Troisièmement, la méthode d’Analyse Fonctionnelle enrichie est appliquée sur 2 cas d’études liés au métro multifonctionnel : l’application de ce concept sur les études de la 5ème ligne de Lyon vers Alaï et l’intégration d’un réseau de fibre optique alimentant l’île de France dans la ligne 16 du projet du Grand Paris. En conclusion des pistes de recherche pour le futur sont proposées : d’autres méthodologies de conception existent avec des objectifs différents (innovation pour la théorie C-K) ou des nouveaux concepts (System of Systems). Ou comment mesurer et quantifier les critères de constructibilité ? Comment appliquer ces méthodes dans différents contextes législatifs et contractuels ? Sont autant de question qui méritent de nouvelles recherches ultérieures / Objectives of the thesis is to enrich Functional Analysis, a design method oriented on the definition of functions, by the integration of two methodological corpuses: Constructability and Systems Engineering in order to adapt it to complex construction products. The enriched method is used and applied on an innovative concept: the multifunctional metro. This new concept consists in the integration of new functions in a metro system: not only transport people but also energy, information, wastes, merchandises, water etc. in order to answer to several city needs with a unique infrastructure. In the introduction, after having describe challenges faced by the construction industry, we highlight that Functional Analysis has been used extensively in other industries to face similar issues. However, its application in the construction industry is limited due to particularities of the construction industry: each project is unique, construction projects are complex and that needs construction projects answer consists in adapting space in order to carry human or related activities. The identification of such particularities have led on one hand, to the consideration of constructability concepts and principles in Functional Analysis to better integrate development constraints of each project in the product development. On the other hand, to the consideration of Systems Engineering, a methodological corpus which objective is to manage complexity of projects. Firstly, Functional Analysis, Constructability and Systems Engineering corpuses are presented and issues are identified in these three methods either to adapt them to complex construction projects for their integration. Constructability notably, is improved with the integration of constraints from Design and Planning phases and a proposition is presented to shift from Constructability to Constructibility. Systems Engineering for its part is adapted by the integration of spatial characteristics of systems. A SysML tool (Systems Modeling Language) has been developed and linked with a BIM modeling tool to improve the capacity to model and verify requirements related to construction systems. The Constructibility matrix, a tool to ease the implementation of constructibility has also been developed.Secondly, Functional Analysis enriched by methodological inputs and tools related to the construction industry is applied. Case studies concern two different phases (planning and design) in two different projects where multifunctionnality concepts have been investigated: the 5th metro line of Lyon where the evaluation of the integration of new functions in the metro line have been studied. And the line 16 of the Greater Paris Project where the integration of a broadband network was the opportunity to study the integration of a new function more in detail (transport information). In conclusion we shall suggest some ways forward by outlining avenues for further researches: how to measure constructibility criteria at different systemic levels is a challenge on which we give some ways to follow. The application and adaptation of Systems Engineering to the construction industry remains to be better investigated and we give some further research indications, particularly on the integration with BIM (Building Information Modeling) methods. We also present how the use of MBSE (Model-Based Systems Engineering) techniques and Data Science could lead to the automation of some design activities which could enrich Functional Analysis methods. Insights on the organization of the profession and contractual issues are proposed and would require more researches to enable implementation of the presented methodology in projects
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Das Städtesystem der Russischen Föderation aus Sicht der Neuen Ökonomischen Geographie / The Russian system of cities from the perspective of New Economic GeographyKauffmann, Albrecht January 2010 (has links)
Der Anstieg der Energiepreise kann zu einer länger anhaltenden Verteuerung von Gütertransporten führen. Welche Auswirkungen haben steigende Transportkosten auf die Entwicklung von Städtesystemen?
Ein solcher Transportkostenanstieg hat in der Russischen Föderation nach der Preisliberalisierung 1992 real, d.h. in Relation zu den Preisen anderer Gütergruppen stattgefunden. Gleichzeitig stellt die Bevölkerungsstatistik der Russischen Föderation Daten bereit, mit deren Hilfe Hypothesen zur Entwicklung von Städtesystemen unter dem Einfluss steigender Transportkosten geprüft werden können. Diese Daten werden in der vorliegenden Arbeit umfassend ausgewertet.
Den theoretischen Hintergrund liefert die Modellierung eines Städtesystems mit linearer Raumstruktur im Rahmen der Neuen Ökonomischen Geographie. Damit wird ein Werkzeug geschaffen, das auch auf weiträumige Städtesysteme mit ausgeprägter Bandstruktur angewendet werden kann. Die hier erstmals erfolgte ausführliche Erläuterung des zu Grunde liegenden Theorieansatzes versteht sich als Ergänzung der Standardlehrbücher der Raumwirtschaftstheorie.
Die Ergebnisse der empirischen Untersuchung bestätigen die Prognose des Modells, dass in großflächigen Ländern bzw. Regionen mit Ähnlichkeit zur unterstellten Raumstruktur ein Anstieg der Transportkosten Konzentrationstendenzen in den Zentren befördert, während die peripheren Regionen zunehmend abgekoppelt werden. / The rise in energy prices may result in long-lasting rise in costs of freight transports. Which effects do rising freight transport costs have for the development of urban systems?
Such rise of transport costs in real terms has happened in Russia after price liberalisation in 1992. At the same time, the Russian official demographic statistics provides data that can be used to test hypotheses concerning the development of urban systems affected by rising transport costs. In the present study, these data are comprehensively evaluated.
The theoretical background is provided by modelling of a linear shaped urban system in the framework of New Economic Geography. By means of this tool, analysis can be applied to spacious urban systems with large transport distances. For the first time, the underlying theoretical approach is explained in detail.
The empirical results provide evidence for the outcomes of the theoretical model: In spacious countries or regions, respectively, whose urban systems are drawn-out on long lines, rising costs of freight transport are conducive to tendencies of concentration of population in large cities in the centre of the system, while peripheral regions are increasingly disconnected.
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Urban shades of green : Current patterns and future prospects of nature conservation in urban landscapesBorgström, Sara January 2011 (has links)
Urban nature provides local ecosystem services such as absorption of air pollutants, reduction of noise, and provision of places for recreation, and is therefore crucial to urban sustainable development. Nature conservation in cities is also part of the global effort to halt biodiversity decline. Urban landscapes, however, display distinguishing social and ecological characteristics and therefore the implementation of nature conservation frameworks into cities, requires reconsideration of what nature to preserve, for whom and where. The aim of this thesis was to examine the current urban nature conservation with special focus on formally protected areas, and discuss their future role in the urban landscape. A social-ecological systems approach was used as framework and both quantitative and qualitative methods were applied. The studies were performed at local to regional scales in the southern part of Sweden. Four key questions were addressed: i) What are the characteristics of nature conservation in urban landscapes? ii) How does establishment of nature conservation areas affect the surrounding urban landscape? iii) In what ways are spatial and temporal scales recognized in practical management of nature conservation areas? and iv) How can the dichotomy of built up and nature conservation areas be overcome in urban planning? Nature reserves in urban, compared to rural landscapes were in general fewer, but larger and included a higher diversity of land covers. They were also based on a higher number and different kinds of objectives than rural nature reserves. Urbanisation adjacent to nature reserves followed the general urbanisation patterns in the cities and no additional increase in urban settlements could be detected. In general, there was a lack of social and ecological linkages between the nature conservation areas and the urban landscape and practical management showed a limited recognition of cross-scale interactions and meso-scales. Such conceptual and physical isolation risks decreasing the public support for nature conservation, cause biodiversity decline, and hence impact the generation of ecosystem services. A major future challenge is therefore to transform current conservation strategies to become a tool where urban nature is perceived, planned and managed as valuable and integrated parts of the city. To enable social-ecological synergies, future urban planning should address proactive approaches together with key components like active enhancement of multifunctional landscapes, cross-scale strategies and border zone management. / At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 2: Manuscript. Paper 3: Submitted. Paper 5: Manuscript.
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