Città europee e nuove forme di pianificazione. Il caso di Bologna

Il tema centrale di questo lavoro è costituito dalle nuove forme di pianificazione territoriale in uso nelle principali città europee, con particolare riferimento all'esperienza della pianificazione strategica applicata al governo del territorio, e dall'analisi approfondita delle politiche e degli strumenti di pianificazione urbanistica e territoriale della città di Bologna, dal Piano Regolatore Generale del 1985-'89 al nuovo Piano Strutturale Comunale del 2008. Più precisamente, le caratteristiche, potenzialità e criticità del nuovo strumento urbanistico del capoluogo emiliano-romagnolo, vengono esaminati, non solo, in rapporto alle caratteristiche tipiche dei piani strategici europei, ma anche alle forme tradizionali della pianificazione urbanistica (i piani regolatori generali) di cui il piano strutturale dovrebbe superare i limiti, sia in termini di efficacia operativa, sia per quanto riguarda la capacità di costruire condivisione e consenso tra i diversi attori urbani, sull'idea di città di cui è portatore. The main topics of this research are the new tools for urban planning used by the main European cities - with particular reference to strategic planning applied to the territorial management - and the analysis of Bologna policies and instruments for urban and territorial planning, from the Piano Regolatore Generale '85-'89, to the Piano Strutturale Comunale in 2008. More precisely, the Bologna new planning instrument's characteristics, potentialities and criticalities, are not only investigated in relation to the fundamental characteristics of European strategic plans, but also to the traditional instruments of Italian urbanistic planning (Piani Regolatori Generali), of which the new structural plan should exceed the limits, both in terms of effectiveness; and in terms of ability to build agreement and sharing on its urban project, between different urban actors.

Leonardo Ricci in the United States (1952-1972). A twenty-year American transfer as a turning experience in teaching and design.

The research solved the historiographic lacuna about Leonardo Ricci’s work in the United States focusing on the span 1952-1972 as a fundamental period for the architect's research, which moved from the project for the community space to macrostructures. The considered period is comprised between Ricci’s first travel to the United States and the date of his resignation from the University of Florida, one year before his resignation from the deanship of the faculty of architecture of Florence (1973). The research retraced philologically the stages of Ricci’s activity in the U.S.A. unveiling the premises and results of his American transfer, and to what extent it marked a turning period for his work as educator and designer and for the wider historiographic contest of the Sixties. The American transfer helped him grounding his belief in avoiding a priori morphological results in favor of what he called the “form-act” design method. Ricci’s research in the U.S.A. is described in his books Anonymous (XX century) and City of the Earth (unpublished). In them and in Ricci’s projects one common thread is traceable: the application of the “form-act” as the best tool to conceive urban design, a discipline established in the United States during Ricci’s first stay at M.I.T., in which he encountered the balance point between architecture and urban planning, between the architect’s sign and his being anonymous, between the collective and the individual dimension. With the notions of “anonymous architecture” and “form-act”, Urban Design and “open work” are the key words to understand Ricci’s work in the United States and in Italy. Urban design’s main goal to design the city as a collective work of art was the solution of that dychothomous research that enlivened Ricci’s work and one possible answer to that tension useful for him to seek the truth of architecture.

Dalla città alla casa, dalla casa alla città: la mutevole ricerca di un Piano per il ben-essere urbano

La ricerca si propone di definire le linee guida per la stesura di un Piano che si occupi di qualità della vita e di benessere. Il richiamo alla qualità e al benessere è positivamente innovativo, in quanto impone agli organi decisionali di sintonizzarsi con la soggettività attiva dei cittadini e, contemporaneamente, rende evidente la necessità di un approccio più ampio e trasversale al tema della città e di una più stretta relazione dei tecnici/esperti con i responsabili degli organismi politicoamministrativi. La ricerca vuole indagare i limiti dell’urbanistica moderna di fronte alla complessità di bisogni e di nuove necessità espresse dalle popolazioni urbane contemporanee. La domanda dei servizi è notevolmente cambiata rispetto a quella degli anni Sessanta, oltre che sul piano quantitativo anche e soprattutto sul piano qualitativo, a causa degli intervenuti cambiamenti sociali che hanno trasformato la città moderna non solo dal punto di vista strutturale ma anche dal punto di vista culturale: l’intermittenza della cittadinanza, per cui le città sono sempre più vissute e godute da cittadini del mondo (turisti e/o visitatori, temporaneamente presenti) e da cittadini diffusi (suburbani, provinciali, metropolitani); la radicale trasformazione della struttura familiare, per cui la famiglia-tipo costituita da una coppia con figli, solido riferimento per l’economia e la politica, è oggi minoritaria; l’irregolarità e flessibilità dei calendari, delle agende e dei ritmi di vita della popolazione attiva; la mobilità sociale, per cui gli individui hanno traiettorie di vita e pratiche quotidiane meno determinate dalle loro origini sociali di quanto avveniva nel passato; l’elevazione del livello di istruzione e quindi l’incremento della domanda di cultura; la crescita della popolazione anziana e la forte individualizzazione sociale hanno generato una domanda di città espressa dalla gente estremamente variegata ed eterogenea, frammentata e volatile, e per alcuni aspetti assolutamente nuova. Accanto a vecchie e consolidate richieste – la città efficiente, funzionale, produttiva, accessibile a tutti – sorgono nuove domande, ideali e bisogni che hanno come oggetto la bellezza, la varietà, la fruibilità, la sicurezza, la capacità di stupire e divertire, la sostenibilità, la ricerca di nuove identità, domande che esprimono il desiderio di vivere e di godere la città, di stare bene in città, domande che non possono essere più soddisfatte attraverso un’idea di welfare semplicemente basata sull’istruzione, la sanità, il sistema pensionistico e l’assistenza sociale. La città moderna ovvero l’idea moderna della città, organizzata solo sui concetti di ordine, regolarità, pulizia, uguaglianza e buon governo, è stata consegnata alla storia passata trasformandosi ora in qualcosa di assai diverso che facciamo fatica a rappresentare, a descrivere, a raccontare. La città contemporanea può essere rappresentata in molteplici modi, sia dal punto di vista urbanistico che dal punto di vista sociale: nella letteratura recente è evidente la difficoltà di definire e di racchiudere entro limiti certi l’oggetto “città” e la mancanza di un convincimento forte nell’interpretazione delle trasformazioni politiche, economiche e sociali che hanno investito la società e il mondo nel secolo scorso. La città contemporanea, al di là degli ambiti amministrativi, delle espansioni territoriali e degli assetti urbanistici, delle infrastrutture, della tecnologia, del funzionalismo e dei mercati globali, è anche luogo delle relazioni umane, rappresentazione dei rapporti tra gli individui e dello spazio urbano in cui queste relazioni si muovono. La città è sia concentrazione fisica di persone e di edifici, ma anche varietà di usi e di gruppi, densità di rapporti sociali; è il luogo in cui avvengono i processi di coesione o di esclusione sociale, luogo delle norme culturali che regolano i comportamenti, dell’identità che si esprime materialmente e simbolicamente nello spazio pubblico della vita cittadina. Per studiare la città contemporanea è necessario utilizzare un approccio nuovo, fatto di contaminazioni e saperi trasversali forniti da altre discipline, come la sociologia e le scienze umane, che pure contribuiscono a costruire l’immagine comunemente percepita della città e del territorio, del paesaggio e dell’ambiente. La rappresentazione del sociale urbano varia in base all’idea di cosa è, in un dato momento storico e in un dato contesto, una situazione di benessere delle persone. L’urbanistica moderna mirava al massimo benessere del singolo e della collettività e a modellarsi sulle “effettive necessità delle persone”: nei vecchi manuali di urbanistica compare come appendice al piano regolatore il “Piano dei servizi”, che comprende i servizi distribuiti sul territorio circostante, una sorta di “piano regolatore sociale”, per evitare quartieri separati per fasce di popolazione o per classi. Nella città contemporanea la globalizzazione, le nuove forme di marginalizzazione e di esclusione, l’avvento della cosiddetta “new economy”, la ridefinizione della base produttiva e del mercato del lavoro urbani sono espressione di una complessità sociale che può essere definita sulla base delle transazioni e gli scambi simbolici piuttosto che sui processi di industrializzazione e di modernizzazione verso cui era orientata la città storica, definita moderna. Tutto ciò costituisce quel complesso di questioni che attualmente viene definito “nuovo welfare”, in contrapposizione a quello essenzialmente basato sull’istruzione, sulla sanità, sul sistema pensionistico e sull’assistenza sociale. La ricerca ha quindi analizzato gli strumenti tradizionali della pianificazione e programmazione territoriale, nella loro dimensione operativa e istituzionale: la destinazione principale di tali strumenti consiste nella classificazione e nella sistemazione dei servizi e dei contenitori urbanistici. E’ chiaro, tuttavia, che per poter rispondere alla molteplice complessità di domande, bisogni e desideri espressi dalla società contemporanea le dotazioni effettive per “fare città” devono necessariamente superare i concetti di “standard” e di “zonizzazione”, che risultano essere troppo rigidi e quindi incapaci di adattarsi all’evoluzione di una domanda crescente di qualità e di servizi e allo stesso tempo inadeguati nella gestione del rapporto tra lo spazio domestico e lo spazio collettivo. In questo senso è rilevante il rapporto tra le tipologie abitative e la morfologia urbana e quindi anche l’ambiente intorno alla casa, che stabilisce il rapporto “dalla casa alla città”, perché è in questa dualità che si definisce il rapporto tra spazi privati e spazi pubblici e si contestualizzano i temi della strada, dei negozi, dei luoghi di incontro, degli accessi. Dopo la convergenza dalla scala urbana alla scala edilizia si passa quindi dalla scala edilizia a quella urbana, dal momento che il criterio del benessere attraversa le diverse scale dello spazio abitabile. Non solo, nei sistemi territoriali in cui si è raggiunto un benessere diffuso ed un alto livello di sviluppo economico è emersa la consapevolezza che il concetto stesso di benessere sia non più legato esclusivamente alla capacità di reddito collettiva e/o individuale: oggi la qualità della vita si misura in termini di qualità ambientale e sociale. Ecco dunque la necessità di uno strumento di conoscenza della città contemporanea, da allegare al Piano, in cui vengano definiti i criteri da osservare nella progettazione dello spazio urbano al fine di determinare la qualità e il benessere dell’ambiente costruito, inteso come benessere generalizzato, nel suo significato di “qualità dello star bene”. E’ evidente che per raggiungere tale livello di qualità e benessere è necessario provvedere al soddisfacimento da una parte degli aspetti macroscopici del funzionamento sociale e del tenore di vita attraverso gli indicatori di reddito, occupazione, povertà, criminalità, abitazione, istruzione, etc.; dall’altra dei bisogni primari, elementari e di base, e di quelli secondari, culturali e quindi mutevoli, trapassando dal welfare state allo star bene o well being personale, alla wellness in senso olistico, tutte espressioni di un desiderio di bellezza mentale e fisica e di un nuovo rapporto del corpo con l’ambiente, quindi manifestazione concreta di un’esigenza di ben-essere individuale e collettivo. Ed è questa esigenza, nuova e difficile, che crea la diffusa sensazione dell’inizio di una nuova stagione urbana, molto più di quanto facciano pensare le stesse modifiche fisiche della città.

What Happened to Participation? Urban Development and Authoritarian Upgrading in Cairo's Informal Neighbourhoods

Participation appeared in development discourses for the first time in the 1970s, as a generic call for the involvement of the poor in development initiatives. Over the last three decades, the initial perspectives on participation intended as a project method for poverty reduction have evolved into a coherent and articulated theoretical elaboration, in which participation figures among the paraphernalia of good governance promotion: participation has acquired the status of “new orthodoxy”. Nevertheless, the experience of the implementation of participatory approaches in development projects seemed to be in the majority of cases rather disappointing, since the transformative potential of ‘participation in development’ depends on a series of factors in which every project can actually differ from others: the ultimate aim of the approach promoted, its forms and contents and, last but not least, the socio-political context in which the participatory initiative is embedded. In Egypt, the signature of a project agreement between the Arab Republic of Egypt and the Federal Republic of Germany, in 1998, inaugurated a Participatory Urban Management Programme (PUMP) to be implemented in Greater Cairo by the German Technical Cooperation (Deutsche Gesellschaft für Technische Zusammenarbeit, GTZ) and the Ministry of Planning (now Ministry of Local Development) and the Governorates of Giza and Cairo as the main counterparts. Now, ten years after the beginning of the PUMP/PDP and close to its end (December 2010), it is possible to draw some conclusions about the scope, the significance and the effects of the participatory approach adopted by GTZ and appropriated by the Egyptian counterparts in dealing with the issue of informal areas and, more generally, of urban development. Our analysis follows three sets of questions: the first set regards the way ‘participation’ has been interpreted and concretised by PUMP and PDP. The second is about the emancipating potential of the ‘participatory approach’ and its ability to ‘empower’ the ‘marginalised’. The third focuses on one hand on the efficacy of GTZ strategy to lead to an improvement of the delivery service in informal areas (especially in terms of planning and policies), and on the other hand on the potential of GTZ development intervention to trigger an incremental process of ‘democratisation’ from below.

The physical city and the urban structure: detecting amenity zones and applying urban morphology to New York

The city is a collection of built structures and infrastructure embedded in socio-cultural processes: any investigation into a city’s transformations involves considerations on the degree to which its composite elements respond to socio-economical changes. The main purpose of this research is to investigate how transformations in the functional requirements of New York’s society have spurred, since the 1970s, changes in both the city’s urban structure and physical form. The present work examines the rise of Amenity Zones in New York, and investigates the transformations that have occurred in New York’s built environment since the 1970s. By applying qualitative measures and analyzing the relationship between urban amenities and the creative class, the present work has investigated changes in the urban structure and detected a hierarchical series of amenity zones classes, namely, Super Amenity Zones (SAZs), Nodal Amenity Zones (NAZs) and Peripheral Amenity Zones (PAZs). This series allows for a more comprehensive reading of the urban structure in a complex city like New York, bringing advancements to the amenity zone’s methodology. In order to examine the manner in which the other component of the city, the physical form, has changed or adapted to the new socio-economic condition, the present research has applied Conzenian analysis to a select study area, Atlantic Avenue. The results of this analysis reveal that, contrary to the urban structure, which changes rapidly, the physical form of New York is hard to modify completely, due to the resilience of the town plan and its elements, and to preservation laws; the city rather adapts to socio-economical changes through process of adaptive reuses or conversion. Concluding, this research has examined the dialectic between the ever-changing needs of society and the complexity of the built environment and urban structure, showing the different degrees to which the urban landscape modifies, reacts and sometimes adapts to the population’s functional requirements.

Experimental and numerical analyses about the efficiency of flow through devices for the sediment controll in urban runoff

As land is developed, the impervious surfaces that are created increase the amount of runoff during rainfall events, disrupting the natural hydrologic cycle, with an increment in volume of runoff and in pollutant loadings. Pollutants deposited or derived from an activity on the land surface will likely end up in stormwater runoff in some concentration, such as nutrients, sediment, heavy metals, hydrocarbons, gasoline additives, pathogens, deicers, herbicides and pesticides. Several of these pollutants are particulate-bound, so it appears clear that sediment removal can provide significant water-quality improvements and it appears to be important the knowledge of the ability of stromwater treatment devices to retain particulate matter. For this reason three different units which remove sediments have been tested through laboratory. In particular a roadside gully pot has been tested under steady hydraulic conditions, varying the characteristics of the influent solids (diameter, particle size distribution and specific gravity). The efficiency in terms of particles retained has been evaluated as a function of influent flow rate and particles characteristics; results have been compared to efficiency evaluated applying an overflow rate model. Furthermore the role of particles settling velocity in efficiency determination has been investigated. After the experimental runs on the gully pot, a standard full-scale model of an hydrodynamic separator (HS) has been tested under unsteady influent flow rate condition, and constant solid concentration at the input. The results presented in this study illustrate that particle separation efficiency of the unit is predominately influenced by operating flow rate, which strongly affects the particles and hydraulic residence time of the system. The efficiency data have been compared to results obtained from a modified overflow rate model; moreover the residence time distribution has been experimentally determined through tracer analyses for several steady flow rates. Finally three testing experiments have been performed for two different configurations of a full-scale model of a clarifier (linear and crenulated) under unsteady influent flow rate condition, and constant solid concentration at the input. The results illustrate that particle separation efficiency of the unit is predominately influenced by the configuration of the unit itself. Turbidity measures have been used to compare turbidity with the suspended sediments concentration, in order to find a correlation between these two values, which can allow to have a measure of the sediments concentration simply installing a turbidity probe.

Quantifying and modeling ecosystem services provided by urban greening in cities of the Southern Alps, N Italy

Population growth in urban areas is a world-wide phenomenon. According to a recent United Nations report, over half of the world now lives in cities. Numerous health and environmental issues arise from this unprecedented urbanization. Recent studies have demonstrated the effectiveness of urban green spaces and the role they play in improving both the aesthetics and the quality of life of its residents. In particular, urban green spaces provide ecosystem services such as: urban air quality improvement by removing pollutants that can cause serious health problems, carbon storage, carbon sequestration and climate regulation through shading and evapotranspiration. Furthermore, epidemiological studies with controlled age, sex, marital and socio-economic status, have provided evidence of a positive relationship between green space and the life expectancy of senior citizens. However, there is little information on the role of public green spaces in mid-sized cities in northern Italy. To address this need, a study was conducted to assess the ecosystem services of urban green spaces in the city of Bolzano, South Tyrol, Italy. In particular, we quantified the cooling effect of urban trees and the hourly amount of pollution removed by the urban forest. The information was gathered using field data collected through local hourly air pollution readings, tree inventory and simulation models. During the study we quantified pollution removal for ozone, nitrogen dioxide, carbon monoxide and particulate matter (<10 microns). We estimated the above ground carbon stored and annually sequestered by the urban forest. Results have been compared to transportation CO2 emissions to determine the CO2 offset potential of urban streetscapes. Furthermore, we assessed commonly used methods for estimating carbon stored and sequestered by urban trees in the city of Bolzano. We also quantified ecosystem disservices such as hourly urban forest volatile organic compound emissions.

Social housing: interventions of densification in urban regeneration (1995-2010). Critical analysis of strategies adopted in Milan, London, São Paulo

The prospect of the continuous multiplication of life styles, the obsolescence of the traditional typological diagrams, the usability of spaces on different territorial scales, imposes on contemporary architecture the search for new models of living. Limited densities in urban development have produced the erosion of territory, the increase of the harmful emissions and energy consumption. High density housing cannot refuse the social emergency to ensure high quality and low cost dwellings, to a new people target: students, temporary workers, key workers, foreign, young couples without children, large families and, in general, people who carry out public services. Social housing strategies have become particularly relevant in regenerating high density urban outskirts. The choice of this research topic derives from the desire to deal with the recent accommodation emergency, according to different perspectives, with a view to give a contribution to the current literature, by proposing some tools for a correct design of the social housing, by ensuring good quality, cost-effective, and eco-sustainable solutions, from the concept phase, through management and maintenance, until the end of the building life cycle. The purpose of the thesis is defining a framework of guidelines that become effective instruments to be used in designing the social housing. They should also integrate the existing regulations and are mainly thought for those who work in this sector. They would aim at supporting students who have to cope with this particular residential theme, and also the users themselves. The scientific evidence of either the recent specialized literature or the solutions adopted in some case studies within the selected metropolitan areas of Milan, London and São Paulo, it is possible to identify the principles of this new design approach, in which the connection between typology, morphology and technology pursues the goal of a high living standard.

Paleosol-based stratigraphy of late Quaternary deposits from the Po basin, between Bologna and the Po river (Northern Italy)

Stratigraphic studies carried out over the last decades in Italy and elsewhere testify a growing interest in Quaternary deposits and in the influence of climate change on their architecture. The subsurface of the Po Plain, in its topmost portion, is made up of alluvial deposits organized in depositional cycles at different scales. This PhD thesis provides millennial-scale stratigraphic reconstruction of the Late Pleistocene-Holocene deposits beneath the southern Po Plain, based on basin-scale correlation of laterally-extensive buried soil horizons. Far from the aim of characterizing palaeosols from a mineralogical and geochemical point of view, we focused on the physical and stratigraphic significance of these horizons. In the Bologna urban area, which hosts an abundance of stratigraphic data, the correlation between seventeen continuously-cored boreholes led to the identification of five vertically-stacked palaeosol-bounded sequences within the 14C time window. In a wide portion of the alluvial plain north of Bologna, far away from the Apenninic margin and from the Po River, where subsurface stratigraphic architecture is dominated by markedly lenticular sediment bodies, palaeosols revealed to be the only stratigraphic marker of remarkable lateral continuity. These horizons are characterized by peculiar resistance values, which make them easily identifiable via pocket penetration tests. Palaeosols reveal specific geometric relationships with the associated alluvial facies associations, allowing reliable estimates of soil development as a function of alluvial dynamics. With the aid of sixty new radiocarbon dates, a reliable age attribution and likely time intervals of exposure were assigned to each palaeosol. Vertically-stacked palaeosols delimitate short-term depositional cycles, likely related to the major episodes of climatic change of the last 40 ky. Through integration of stratigraphic data with 750 archaeological reports from the Bologna area, the impact of human settlements on depositional and pedogenic processes during the late Holocene was investigated.

Soil-structure interaction during tunnelling in urban area: observations and 3D numerical modelling

This work illustrates a soil-tunnel-structure interaction study performed by an integrated,geotechnical and structural,approach based on 3D finite element analyses and validated against experimental observations.The study aims at analysing the response of reinforced concrete framed buildings on discrete foundations in interaction with metro lines.It refers to the case of the twin tunnels of the Milan (Italy) metro line 5,recently built in coarse grained materials using EPB machines,for which subsidence measurements collected along ground and building sections during tunnelling were available.Settlements measured under freefield conditions are firstly back interpreted using Gaussian empirical predictions. Then,the in situ measurements’ analysis is extended to include the evolving response of a 9 storey reinforced concrete building while being undercrossed by the metro line.In the finite element study,the soil mechanical behaviour is described using an advanced constitutive model. This latter,when combined with a proper simulation of the excavation process, proves to realistically reproduce the subsidence profiles under free field conditions and to capture the interaction phenomena occurring between the twin tunnels during the excavation. Furthermore, when the numerical model is extended to include the building, schematised in a detailed manner, the results are in good agreement with the monitoring data for different stages of the twin tunnelling. Thus, they indirectly confirm the satisfactory performance of the adopted numerical approach which also allows a direct evaluation of the structural response as an outcome of the analysis. Further analyses are also carried out modelling the building with different levels of detail. The results highlight that, in this case, the simplified approach based on the equivalent plate schematisation is inadequate to capture the real tunnelling induced displacement field. The overall behaviour of the system proves to be mainly influenced by the buried portion of the building which plays an essential role in the interaction mechanism, due to its high stiffness.

Towards the Enabling City: Intermediate Places between Practices and Planning for Social Innovation in Bologna

The research investigates the interaction between social innovation practices and urban planning, assuming as a case study and field of application the city of Bologna, observed from the point of view of the production of urban policies and with respect to the places where it is practiced. Social innovation are localised actions tackling current urban complexities with micro-scale practices of service and urban production, by which new urban actors find answers to social needs, which are less afforded by the market and the public sectors. Planning and social innovation practices are two dimensions working in the city in different but complementary ways, subject to a mismatch. Through the lenses of interaction, the research explores the context of Bologna, a paradigmatic study and application field, a laboratory of innovative policies where a tradition of collective civic initiatives intertwines with a more responsible institutional planning framework. After drawing from area-based policies of Berlin and Barcelona, the thesis reads the role of specific intermediate places, mediators in bridging the level of institutions and the practices. Through an inventory and a cross-cutting taxonomy of intermediate places, the research draws the knowledge to inform a new urban model for the city of Bologna, aimed at overtake the mismatches by enabling the practices to act, allowing urban planning to frame them in a cross-fertilisation dimension. The proposed urban diagrammatic model, foresees intermediate places as local socio-urban observatories for research and development, interacting with both institutions and communities. The goal is to critically explore the limits and widen the meaning of the capacity of action of social innovation practices engaging in mutual-learning with the city. The model suggests a new possibility for reflection on urban planning as a more flexible approach, which translates the numerous experiences of the city into alternatives and multiple visions.

Essays in Economic Geography and Long-Term Development

This dissertation has two main themes: first, the economic impact of tourism on cities and, secondly, the determinants of European long-run development, with a focus on the pre-Industrial era. The common thread is the attempt to develop economic geography models that incorporate spatial frictions and are liable to be given empirical content. Chapter 1, written in conjunction with G. Alfredo Minerva, provides an empirical analysis of the relationship between tourism and economic activity across Italian municipalities, and lays down the basic elements of an urban theory of tourism in an a-spatial setting. Chapter 2 extends these ideas to a quantitative urban framework to study the economic impact and the welfare consequences of tourism into the city of Venice. The model is given empirical content thanks to a large collection of data at the Census tract level for the Municipality of Venice, and then used to perform counterfactual policty analysis. In chapter 3, with Matteo Santacesaria, we consider a setting where agents are continuously distributed over a two-dimensional heterogeneous geography, and are allowed to do business at a finite set of markets. We study the equilibrium partition of the economic space into a collection of mutually-exclusive market areas, and provide condition for this equilibrium partition to exist and to be unique. Finally, chapter 4 "The rise of (urban) Europe: a Quantitative-Spatial analysis", co-authored with Matteo Cervellati and Alex Lehner, sets up a quantitative economic geography model to understand the roots of the Industrial Revolution, in an attempt to match the evolution of the European urban network, and the corresponding city-size distribution, over the period A.D. 1000-1850. It highlights the importance of agricultural trade across cities for the emergence of large manufacturing hubs.

Greening the city: an ecosystem-based framework to support planning towards urban sustainability and resilience

Cities are small-scale complex socio-ecological systems, that host around 60% of world population. Ecosystem Services (ES) provided by urban ecosystems offer multiple benefits necessary to cope with present and future urban challenges. These ES include microclimate regulation, runoff control, as well as opportunities for mental and physical recreation, affecting citizen’s health and wellbeing. Creating a balance between urban development, land take containment, climate adaptation and availability of Urban Green Areas and their related benefits, can improve the quality of the lives of the inhabitants, the economic performance of the city and the social justice and cohesion aspects. This work starts analysing current literature around the topic of Ecosystem Services (ES), Green and Blue Infrastructure (GBI) and Nature-based Solutions (NBS) and their integration within current European and International sustainability policies. Then, the thesis focuses on the role of ES, GBI and NBS towards urban sustainability and resilience setting the basis to build the core methodological and conceptual approach of this work. The developed ES-based conceptual approach provides guidance on how to map and assess ES, to better inform policy making and to give the proper value to ES within urban context. The proposed interdisciplinary approach navigates the topic of mapping and assessing ES benefits in terms of regulatory services, with a focus on climate mitigation and adaptation, and cultural services, to enhance wellbeing and justice in urban areas. Last, this thesis proposes a trans-disciplinary and participatory approach to build resilience over time around all relevant urban ES. The two case studies that will be presented in this dissertation, the city of Bologna and the city of Barcelona, have been used to implement, tailor and test the proposed conceptual framework, raising valuable inputs for planning, policies and science.

Relationships between airborne pollen allergens and environmental factors.

This thesis is a collection of scientific papers resulting from my research activity during the PhD course in Earth, Life, and Environmental Sciences. The main subject of the thesis is the capability of pollen to trigger a hypersensitive reaction in different environmental conditions, and the need to better characterise such allergenicity in order to measure it. This topic is discussed from different perspectives, using ecological, morphological, and molecular approaches. The thesis starts by summarising the importance of green infrastructures in the cities, from economical and conservational perspectives. It then focalises on the lesser-known ecosystem disservices urban vegetation can provide, and in particular on pollen allergy, exploring its causes and illustrating possible ways to monitor, foresee, and mitigate the allergenic risk. The possibility to monitor the allergenicity of urban green areas is then examined in depth, with an original research paper that proposes a method standardisation for existing allergenicity indices (Specific Allergenic Index and Urban Green Zones Allergenicty Index), and compares the indices results to evaluate their effectiveness. At the end of the thesis, pollen allergenicity is also approached from a molecular perspective, by investigating pollen allergens release mechanisms in the context of pollen hydration and germination. In particular, in an unpublished original research paper, the nature of allergen-carrying extracellular nanovesicles (pollensomes) released by pollen is extensively studied on a non-allergenic pollen model, to understand their biological role and thus the environmental conditions that trigger their release. Moreover, the last paper reported in the thesis demonstrates the secretion of a potential pollen allergen, a low-molecular weight cyclophilin, during pollen germination under stressful conditions. The thesis concludes with a brief description of other scientific activities carried on during the PhD, that still need more scientific corroboration to be published.

Design of mobility infrastructures to promote sustainability and accessibility of urban areas

This doctoral dissertation represents a cluster of research activities carried out at the DICAM Department of the University of Bologna during a three-year Ph.D. course. The goal of this research is to show how the development of an interconnected infrastructure network, aimed at promoting accessibility and sustainability of places, is fundamental in a framework of deep urban regeneration. Sustainable urban mobility plays an important role in improving the quality of life of citizens. From an environmental point of view, a sustainable mobility system means reducing fuel discharges and energy waste and, in general, aims to promote low carbon emissions. At the same time, a socially and economically sustainable mobility system should be accessible to everybody and create more job opportunities through better connectivity and mobility. Environmentally friendly means of transport such as non-motorized transport, electric vehicles, and hybrid vehicles play an important role in achieving sustainability but require a planned approach at the local policy level. The aim of this study is to demonstrate that, through a targeted reconnection of road and cycle-pedestrian routes, the quality of life of an urban area subject to degradation can be significantly improved just by increasing its accessibility and sustainability. Starting from a detailed study of the European policies and from the comparison with real similar cases, the case study of the Canal Port of Rimini (Italy) has been analysed within the European project FRAMESPORT. The analysis allowed the elaboration of a multicriterial methodology to get to the definition of a project proposal and of a priority scale of interventions. The applied methodology is a valuable tool that may be used in the future in similar urban contexts. Finally, the whole project was represented by using virtual reality to visually show the difference between the before and after the regeneration intervention.