LA DETERMINACIÓN DEL CORTISOL Y LA RESPUESTA AGUDA O CRÓNICA

3.8.1 Policy context

Policies addressing the management and use of green areas in the city of Trento focus on the reduction of the inequality in the access to urban green spaces and the promotion of citizens’

involvement and ownership of public green area. The main policy instrument that will directly affect the city’s green infrastructures in the next future is the forthcoming revision of the Urban Plan. The municipal planning department has just completed a background study with the aim of assessing the multi-functional value of the green infrastructures outside the most urbanized part of the city, including agricultural fields, forests, pastures and other green areas. Through a process of expert consultation, the study identified and combined a set of spatially-explicit criteria related to five dimensions, namely: (1) ecological-environmental; (2) economic-productive; (3) aesthetic-perceptual; (4) historical-cultural; (5) touristic-recreational. The results will set the basis of a new classification of these green areas and of the regulations for their safeguard to be included in the future planning instruments.

The mapping and assessment of ecosystem services undertaken by the University of Trento focuses on the green infrastructures within the most urbanized part of the city, and aims at complementing this analysis thus providing additional information to support the future planning decisions.

3.8.2 Mapping urban ecosystems

Relatively few data are currently available for mapping urban ecosystems in the city of Trento.

Among them, the high-resolution aerial photograph produced in 2015 and the municipal database of public green spaces are the most useful information.

The database includes detailed geo-referenced data about, among others, trees species and dimensions, land cover, boundaries and accesses to public green areas. Unfortunately, these data are incomplete and partially out of date, and cover only a small portion of the city green infrastructures.

Researchers from the University of Trento are developing a new purpose-built database, which combines data from different sources and integrates the available information into a complete mapping at the city scale.

The database includes also information about the structure of the urban green space (e.g., size, tree canopy coverage, soil cover), as well as its function and use, which provides input for the mapping and assessment of ecosystem services.

45 | P a g e 3.8.3 Mapping ecosystem services

The ongoing research activity focuses on priority ecosystem services identified for the city. Trento is located in a narrow valley floor surrounded by mountain landscape rich of natural and protected areas. The urban areas, home to 120 000 inhabitants, has a dense core in the valley floor and several hamlets spread on the hills. These factors determine a marginal role of the urban ecosystems in the overall landscape performances of the region, and a lower demand, compared to other cities, for certain green recreational activities, which can be easily accessed in the surrounding natural landscape. Given these conditions, the analyses focus on four regulating services (microclimate regulation, air filtration, noise mediation, water flow maintenance and flood protection), and on a set of cultural services.

The supply of regulating services is assessed through models tailored to the city scale and based on the biophysical data collected in the new database. The demand is determined with reference to the conditions of both the urban environment and the urban population. Thus, environmental monitoring data (air pollution, noise pollution, soil sealing, etc.) are combined with spatial analysis of population density and service-specific vulnerability indicators.

Table 13 provides an overview of the mapping and assessment approach that is being applied for the selected regulating services. The assessment of cultural services focuses on their contribution to citizens’ physical and mental health. The aim is to measure the benefits that different categories of users gain from different types of physical and experiential interactions with urban green spaces. The use of green infrastructures for physical activity and mental restoration will be investigated through the analysis of users’ preferences in relation with specific features of the infrastructures themselves, combining a variety of methods (e.g. questionnaires and surveys;, mining of data from social-media geographic information and volunteered geographic information platforms).

Table 13. Mapping and assessment approach for regulating and maintenance services.

Ecosystem service Supply

indicator Demand indicator (conditions of

the urban environment) Demand indicator

(population and

vulnerability) Microclimate regulation Cooling

effect (ΔT)

Urban Heath Island Density and vulnerability to heat

Air filtration PM10

captured Air pollution concentration Density

Noise mediation Noise

reduced Noise sources Density and vulnerability to

noise effect produced on their surroundings have been mapped by applying a method specifically tailored to the urban scale. The method estimates the two main functions involved in cooling, namely shading and evapotranspiration and provides a classification of each portion of the urban green infrastructure according to the type of soil cover, the percentage of canopy cover and the dimension of the area.

Each class, depending on the climatic zone, can be linked to a range of temperature differences between the analyzed area and the surroundings. Then, by applying different decay functions depending on the dimension and the shape of the areas, it is possible to map its cooling effect and to

assess to what extent the presence of urban green infrastructures influences the microclimate of the city.

Figure 14 shows the two maps of the cooling capacity and of the cooling effect of the urban green infrastructures in the most urbanized part of the city of Trento. The former allows identifying the different components, classified according to their cooling capacity. The latter shows how the ecosystem service is distributed inside the city. A test application has been performed on the current urban plan to demonstrate a potential use of the results in the planning process (Geneletti et al., 2016). Two greening scenarios have been developed for each of the thirteen redevelopment sites - mostly former industrial areas - identified by the plan, and their effects in terms of cooling have been assessed by crossing the cooling effect with detailed data regarding the distribution and vulnerability characteristics of the population. The comparison of the scenarios with the baseline condition produces a quantitative estimate of the number of citizens and vulnerable people that benefit from each intervention, providing a beneficiaries-based indicator to measure the expected impacts of planning alternatives.

From these preliminary results, it is possible to identify four main potential contributions of the ecosystem services assessment to the urban planning process. These correspond to different steps in the drafting of the urban plan and of the associated Strategic Environmental Assessment (SEA):

 Enhancement of the baseline knowledge through the inclusion of data regarding the amount and the spatial distribution of ecosystem services – and of their beneficiaries - in the city.

 Extension of the set of methods and indicators available for the comparison of planning options through the inclusion of innovative, beneficiaries-based metrics.

 Inclusion of nature-based solutions in the plan, fostered by the possibility of analyzing their benefits and effectiveness as well as their co-benefits in terms of other ecosystem services produced.

 Improvement of the follow-up and monitoring activities through a continuous update of the ecosystem services mapping and assessment.

47 | P a g e Figure 14. Maps of the cooling capacity (left) and of the cooling effect (right) of the urban green infrastructures in the city of Trento. Cooling capacity is expressed in classes from A+ (highest capacity) to E (lowest capacity). Source: Geneletti et al. (2016)