2. Public green spaces in urban planning
In the current panorama, a renewed interest in the theme of landscape and urban green can be found. This factor is caused by the growing collective sensitivity to the environment and by the awareness of today's worrying situation which places the territory we inhabit in serious danger. This is how environmental movements and associations for the protection of the environment make their way and express the need for constantly updated laws on landscape plans.
Despite these first steps towards greater collective participation, today the territorial planning at the municipal level and the legislation do not pay due attention to urban greenery and its protection. In step with the international political commitment on sustainability, Italy introduced in 2013 a law concerning public green spaces and its protection - lex 14 January 2013, n.10. However, these are often premises that are not considered in practice or are applied sporadically and not globally.
It is necessary to approach this issue in a systematic way using the specific governance tools through which to implement the planning and correct management choices.
Although there are numerous differences at municipal level between Italian cities, there are three tools used by the administration for the regulation of urban territories:
Analysis and monitoring tool: Green Census
Section in which public and private green areas in the urban and peri-urban area are analyzed. A classification of the main species and the relative distribution identified through relief on paper is also reported.
Regulatory tool: Green regulation
It concerns the rules relating to the design, insertion and future management of green areas.
The types of plants that can be used depending on the context and needs are taken into consideration.
Strategic planning tool:
Urban green plan
It manages the methods for implementing public green areas.
To these are added the Green monitoring and management plan, variable from year to year according to municipal needs and aimed at guaranteeing citizens satisfactory services and the Green Information System.
Urban Green Plan
The Urban Green Plan is the instrument that determines the set of interventions aimed at promoting the qualitative and quantitative development of urban green and deals with its management and maintenance measured with respect to the specific context.
If applied correctly, it can bring many environmental benefits, reducing the impact of urban activity on the territory, in order to restore the green structure coveted by the citizens themselves. The Urban Green Plan is an integral part of the territorial strategic planning and is composed of the following sections:
- Cognitive framework
- Address plan
- Implementing technical standards
Too often, the Green Plan is erroneously considered as a sector tool in its own right, when instead it is a document complementary to the entire urban planning. In fact, it is useful for knowing, preventing and conserving the territory subject to planning. Furthermore, the Urban Green Plan should involve the population in the design choices and decision-making processes that affect the territories it inhabits. Unlike other European countries, in Italy landscape planning is not entrusted to the city council but is managed at provincial level with the Provincial Territorial Coordination Plans. It would be good practice instead, to establish the General Town Plan (PRG) taking into account the environmental set-up, thus coordinating the various aspects in a single tool considered at a global level that regulates the buildings and infrastructures on the basis of landscape planning. This disordered and communication-free structure does not encourage planning in the country according to awareness and respect for the environment. In fact, according to a recent analysis conducted by ISPRA (Higher Institute for Environmental Protection and Research), despite the growing interest in sustainable development and environmental protection, few bodies in Italy have prepared the urban green plan. In fact, only 7 cities have applied the principles of this instrument: Milan, Venice, Bologna, Parma, Prato, Reggio Calabria and Cagliari.
This bad habit generates numerous management and maintenance problems in the cities we live in. For example, the absence or scarcity of green areas integrated into the built environment, the low quality of the ecosystem, little frequented and consequently unsafe gardens and parks.
It is therefore necessary to act at all scales, keeping firmly in mind a plan that considers the city in all its parts and above all the green, an indispensable element of connection of the entire urban fabric.
Urban green policies, as already mentioned, often prove to be deficient also due to the lack of information on green spaces within cities. The direct consequence is given by the collective disinformation of the value of this unfortunately underestimated resource: it is necessary to introduce a global information system, accessible to all, capable of monitoring and managing this collective heritage.
To this end, a typological classification of urban green areas has been drawn up:
GREEN SPACES AT THE NEIGHBORHOOD LEVEL → the public gardens, the ones belonging to the residences, the play areas, the greenery at the service of commercial and production areas are part of it.
GREEN SPACES AT THE MUNICIPAL LEVEL → the green is intended for urban sports equipment, medium-sized public parks, wooded areas or riverside areas.
CONNECTIVE ELEMENTS FOR THE CREATION OF GREEN SPACE NETWORKS → cycle paths, tree-lined avenues, pedestrian areas.
The typological classification must take into consideration all the characteristics of the spaces it considers, including the dimensions.In this regard, the subdivision according to the size classes provides:
- SMALL SPACES → gardens of less than 1,500 m2
- MEDIUM - SMALL SPACES → gardens between 1,500 m2 and 5,000 m2
- MEDIUM - LARGE SPACES → gardens between 5,000 m2 and 10,000 m2
- LARGE SPACES → parks over 10,000 m2
As you can see, the transition from garden to park occurs over 10,000 m2. In the analysis and management of urban green, reference is made to some indicators capable of signaling situations of criticality or poor use. They are functionality, services and furnishings, safety, aesthetic quality, contextual pressure factors and maintenance.
From the point of view of functionality, it is preferable to organize the area in areas equipped and designed for a specific use so as to encourage socialization between different users and prevent possible conflicting phenomena.
It will thus be optimal to enclose the area intended for children's play and that intended for dogs, also to ensure the safety of all users. The furniture will be of fundamental importance and necessary for the differentiation of use: comfortable seats and recreational tables for the elderly, parking spaces for bicycles, toilets and baskets for waste collection. In addition, all spaces must be easily accessible: clearly visible and tangible entrances and exits, obstacle-free routes and absent architectural barriers.
It is essential that during the design phase, the functional aspect but also that relating to aesthetic quality is taken into account as it constitutes an important added value that pushes to frequent the area more. The influx of people thus makes the spaces frequented and more alive and gives a sense of greater security. Although a careful design that takes into account the factors mentioned above is the basis for the creation of successful collective spaces, there are some elements that can sometimes compromise their balance.
These are external pressure factors and space management over time. For example, the presence of high-traffic roads characterizes the greatest threat in terms of noise and air pollution. The proximity of railways is also a cause of serious disturbance for the noise produced.
As far as maintenance is concerned, it is a clear indicator of the physical-environmental quality of the green area; the care of the turf, sometimes very demanding, should be a fundamental prerogative in order to keep the surface continuous and free of dirt areas. The routes must be clean and free of obstacles, the furniture elements efficient and in good state of conservation. It is also important to keep the area clean, there must be no dog waste and excrement. Of course, the civic sense of the users is a determining element for the quality of the collective spaces, too often prey to carelessness and a lack of sense of belonging.
The urban environment lends itself to welcoming green spaces as active elements with various functions; they fulfill the role of social incubators for sports and leisure activities and improve the environmental and aesthetic conditions of the city. For this reason, urban green has now taken on a significant importance by changing its function from a mere residual element to an actor necessary for the community.
Subsequently, some of the functions covered by urban greenery are included, which contribute to the improvement of the psycho-physical conditions of the individual who lives in the city and lead to the re-naturalization of the city environment.
As is well known, in the city there is an excess of carbon dioxide caused by vehicle engines, by domestic activities and by the action of industrial and residential plants.
Through the photosynthesis process, plants are able to capture and retain dust suspended in the atmosphere, subsequently releasing oxygen. Even the grassy expanses of the
meadows and green soil exercise a purifying function since they are positioned at the same height as the exhaust fumes of cars. The polluting particles present in the atmospheric dust are captured by the leaves which have different capacities depending on the size and characteristics of the leaves themselves. The trees retain a much higher quantity of dust than the turf which in turn intercepts a quantity six times greater than that of smooth surfaces. Furthermore, the plant species are able to contribute to the correct thermal regulation: the green masses avoid excessive heating of the soil by blocking the evaporation of the water contained inside it. This is how a tree cools the environment with the capacity equal to that of five medium power air conditioners; this equates to a saving of 40% in economic and energy terms for summer heat conditioning.
Noise is considered a relevant pollution factor as it causes significant psycho-physical damage to individuals. The urban context is increasingly characterized by the presence of numerous sources of noise and for this reason the green areas must contribute to the mitigation of the damages that follow. To this end, anti-noise screens are inserted in the collective green areas, which act by absorbing, reflecting or diverting the sound energy. Another method is that of attenuation of sound, obtained by lengthening the path of sound waves from the source to the reception point.
The plant barriers act with more or less intensity depending on the characteristics of the plants used: the species with foliage also present in the lower part of the trunk and evergreens are perfect to guarantee protection throughout the year. The protective result also varies according to the thickness and height of the screen, in fact the most advantageous solution is characterized by high hedges and with a thickness of at least 5 meters. Green barriers are also excellent solutions for visual isolation.
Since ancient times it has been shown that the presence of the green element in the human environment improves the living conditions of the individual. The vegetation would in fact help to maintain a balance from the point of view of the hygiene of the places and consequently of the well-being of the person.
From a recreational point of view, green spaces are perfect for the correct growth of the child who can play and interact in the open air. The healthy areas protected by the rest of the city are not only useful for children but also for adults and the elderly who can meet here, play sports and relax in their free time. In addition, the therapeutic function of the green element is also recognized since in an environment rich in vegetation man is "lightened" by the overload of daily thoughts and worries.
In fact, it has been shown that at the sight of some plant species, human blood pressure and muscle tension are lowered.
Although the current trend considers the functional aspect of the green areas to be the main aspect, aesthetics is not an element to be overlooked. In addition to improving the entire urban environment, a well-designed space from a formal point of view ensures a differentiation from the monotony of buildings and streets.
Furthermore, areas rich in vegetation improve views and city views, the potential of which is sometimes not even taken into consideration.
Functional scheme of green inserted in the urban fabric