Littérature scientifique sur le sujet « Vegetazione urbana »

Palermo is a lot of landscapes. It is a geography of exaggerated places able to generate a condition of constant wonder in those who cross it. The many souls of different peoples who have inhabited it and who still inhabit it constitute a mosaic made of very close and uncovered relationships between plants, animals, men, sea and light. This contribution aims to explore - not in an exhaustive way - some conditions of coexistence that have been observed within the open spaces of the city (in particular of its Kalsa district). They are interesting because show us how spontaneous links between different species and objects (mostly ruins of the Second World War) constitute places of unprecedented beauty and social cohesion functioning in complex urban tis- sues. In front of this evidence there is the need to establish new interpretative categories of the existing, in order to generate a taxonomy. It could identify the possible active roles that the relationships and coexistences already acting can have within the project of the city (turning them into gardens, for example) and which ones should be defused because they are harmful to the inhabitants and to nature

Lo scritto si basa sulle cartografie a grande scala disegnate nel XVIII secolo, soprattutto dal 1740, anno della ricognizione generale di Pompeo Neri e Tommaso Perelli. I committenti furono la grande proprietŕ fondiaria (Salviati, Mensa Arcivescovile di Pisa, Scrittoio delle Regie Possessioni) e gli uffici dell'amministrazione lorenese competenti in materia di lavori pubblici, di controllo politico-amministrativo del territorio e di gestione agricolo-forestale delle tante fattorie e tenute pubbliche. L'integrazione e la comparazione dei documenti consente di ricostruire l'assetto territoriale d'insieme della pianura a nord e a sud dell'Arno (tra Massaciuccoli e Livorno), con le trasformazioni avvenute dopo il 1740. Emergono i diversi ambienti e paesaggi che si susseguono dal mare all'interno, sotto il profilo geomorfologico-idrologico (spiagge e tomboli, lame e zone umide, bassa e alta pianura) e vegetazionale (foresta sempreverde, pineta, foresta planiziaria, pascoli naturali e prati artificiali, coltivazioni). Sono anche messe in luce le dinamiche che riguardano l'azione umana su: i corsi d'acqua, i canali artificiali e i recinti di colmata, le strade e le poche sedi umane stabili e temporanee, correlate alla fruizione agro-forestale del territorio, al di lŕ dei centri urbani di Pisa e Livorno e del sistema delle fortificazioni costiere.

Topic of green walls is important for contemporary architectonical experimentation and R&D: it express an expansion of designer’s possibilities. The use of vegetation like a functional element in the project is may be found for a long time, but only recently, thanks to the attention for environmental conditions and the consequent cultural moving towards a sustainability development, the architectonical use of plants like collaborative components is increasing. This research shoots for a detailed analysis, with the aim to understand the features of these particular typologies (green façades, living walls, etc.), which ask a collaboration between technological components and living system represented by plants. Technical and functional development characterizing these envelope systems were the target of all methodological research’s choices, with the aim to draw up some planning instruments for the architect.

Progettare spazi e servizi nelle periferie delle grandi città è una grande sfida per i architetti ed urbanisti. É questo il caso del quartiere Barca a Bologna, un’area dalle grandi dimensioni e potenzialità che si trova in una condizione di degrado dovuta a diversi fattori, quali la distanza dal centro e la mancanza di servizi. Il progetto ha come obbiettivo ricucire il rapporto tra quest’area periferica e il centro della città, cercando di trasformare il quartiere Barca in un nuovo polo attrattivo per nuove attività locali e capace di gestire flussi di persone a livello nazionale, vista la vicinanza alla ciclovia del Sole. A tal fine sono stati presi in considerazione gli elementi più significativi del tessuto urbano circostante come fonte ispiratrice del progetto, soprattutto l’edificio del “Treno”, elemento particolarmente rilevante dell’area, per generare nuovi spazi di aggregazione e servizi per il quartiere. Il progetto ha come obiettivo quello di realizzare una lunga passeggiata commerciale affiancata da aree verdi che ne migliorino la qualità in termini di paesaggio urbano. L’intervento segue le linee-guida della sostenibilità, della connettività e della valorizzazione del verde pubblico: il progetto propone una rilettura della periferia come nuovo polo attrattivo, intervenendo alla scala di quartiere sulla riorganizzazione della viabilità, degli spazi pubblici, dei servizi e degli alloggi del quartiere Barca.

The world's urban population is increasing as well as urbanized areas. The growth of urban populations means that most people will experience urban climate, that is significantly different from the rural one. Urban climate is a very complex field of study because of the great number of characteristics that affect weather variables in the urban environment and because of the different kind of morphologies and materials used in cities all over the world. Furthermore, cities have an important role to play in mitigating climate change but the present climatic knowledge is not yet applied by urban planners. There is a need to increase the climatic knowledge of urban areas all over the world and to translate it into a planning language in order to facilitate the design of more sustainable cities. The aim of this PhD thesis is to quantify the intra-urban thermal variability of the city of Florence and to study the influence of vegetation and other urban indicators on air temperature and the results could be an useful tool for urban planners and policymakers. A network of air temperature sensor was used to monitor the thermal trend in various part of the city. Data were collected every fifteen minutes since December 2005. The thermal variability was quantified by applying some climatological and degree-day indices. The role of vegetation and of other urban characteristics was evaluated by analyzing the relationship between air temperature and some urban indicators, such as green cover ratio, street cover ratio and building volume. The effect of vegetation on maximum and minimum air temperature during the summer period was also evaluated during particular synoptic conditions in parks and streets with different vegetation type. Results show an intra-urban thermal variability comparable to the urban rural one. Four thermal level were found inside the city in all seasons and the average difference between maximum and minimum air temperature was of 2 °C in winter, spring and autumn and of 3 °C in summer. An average difference of more than ten frost days in winter and of more than 12 summer days (days with maximum air temperature higher than 25 °C) in summer was found. The intra-urban difference of the tropical nights (days with minimum temperature higher than 20 °C) was even more evident, with a maximum of 42 days versus 10 days during the summer period (total of 92 days). Concerning the role of vegetation, a significant negative relationship between green cover ratio and summer minimum and maximum temperatures was found. The reduction of maximum air temperature (0.18 °C for each 10% increase of tree cover ratio in an area of 250 meters radius centred in the thermal sensor) determined by vegetation is significant only on its proximity (less than 50 meters) and it is related to the presence of trees. The reduction of minimum air temperature is higher (0.58 °C for each 10% increase of green cover ratio in an area of 250 meters radius centred in the thermal sensor) and related to the urban morphology both near the temperature sensor and at larger areas, confirming previous studies on the relationship between the magnitude of the urban heat island phenomenon and the size of the city . Finally, the effect of the presence of trees in the urban environment was analysed. In strong urbanized context, such as a parking lot, it was shown that the presence of a single tree reduced the maximum air temperature of almost 1 °C near of it during summer. In addition, the tree cover intensity was also analysed and the results show that green areas with a total tree cover had lower maximum air temperatures and higher minimum temperatures than grass green areas. A mean 3 °C difference was registered in maximum values and a 2 °C difference was found in minimum temperatures. Areas with a medium tree coverage showed a midway trend. Gaps in areas with a medium tree coverage had a similar trend for maximum values to areas with a total tree cover and for minimum values to grass areas. The results of this study can find application in several field of study, such as phenology and human health, such as the production of biometeorological maps for plant flowering and to classify areas at higher risk during the heat waves or cold spells. Furthermore, these results could be useful for planners and policymakers to take action towards urban temperature mitigation.

La crescente richiesta di città più ecologiche e sostenibili impone il ripensamento dei manufatti e delle attrezzature che vanno sotto la denominazione di infrastrutture urbane. Diventate un imprescindibile componente fisica dell’ecosistema urbano hanno infatti assunto, nella città contemporanea, l’involontario ruolo di testimoni della contrapposizione tra contesto naturale e ambiente artificiale. Attualmente oggetto di una riflessione critica che sta spostando l’interesse dalla loro configurazione estetico/funzionale alla verifica di compatibilità ambientale e paesaggistica, esse possono essere ripensate, anche grazie all’impiego della vegetazione e del verde tecnologico, quale azione preliminare verso la loro rigenerazione e quella degli “infra-luoghi” che ad esse si accompagnano. Al di là delle tendenze modaiole, che sovente scadono nel greenwashing, l’inverdimento delle infrastrutture può rappresentare l’occasione per rendere ambientalmente più sostenibili consistenti porzioni di città, anche in ragione degli importanti benefici che la vegetazione produce: riduzione dell’isola di calore, controllo del deflusso delle acque piovane, abbattimento dell’inquinamento atmosferico e del rumore, etc. In questo contesto i dispositivi del camouflage, attuati con il verde, possono aprire ad una nuova estetica, favorendo la dissimulazione di queste attrezzature all’interno della città. Il saggio propone un primo bilancio di una ricerca, tutt’ora in corso, sulle potenzialità dell’impiego della vegetazione nella città densa quale strumento con cui ripensare e riabilitare le infrastrutture e i relativi spazi, che deturpano il paesaggio urbano, formulando alcune riflessioni, contestualizzate per concreti risultati raggiunti, su come le tecniche del camouflage e della mimicry possono contribuire a migliorare il ruolo e la natura di queste attrezzature urbane, altrimenti solo ed esclusivamente funzionali. The growing demand for more environmentally friendly and sustainable cities requires the rethinking of the artifacts and equipment that we commonly call gray infrastructure. They have become an inevitable physical component of the urban ecosystem and have in fact assumed, in the contemporary city, the involuntary role of witnesses to the contrast between natural and artificial environment. Gray Infrastructures are currently subject to a critical reflection about their environmental compatibility as well as their aesthetic/functional configuration; that is why they can be rethought, by use of vegetation and ecotechgreen, to regenerate the "infraplaces" which they accompany. Beyond the greenwashing, the greening of infrastructure could be an opportunity to make more environmentally consistent parts of the high city, also because of the important benefits that vegetation produces: heat island reduction, control of storm water runoff, reducing air pollution and noise, etc. Intervening in many environmental aspects, ‘ecotechgreen’ becomes the premise for a new environmental planning with which to transform towns into more efficient ecosystems. In this context, the devices of camouflage, practiced by ecotechgreen, can open a new urban aesthetic, facilitating the disguise of these facilities within the city. This paper presents partial results of an ongoing research, about different planning approaches relative to these urban components into the high density city, and it shows how the techniques of camouflage and mimicry may help to improve the role and nature of these urban facilities.