**2. Literature Review**

In recent decades, urban development has restricted green space in cities whether by removal of vegetation or increase of impervious surfaces in cities' streets [9–11]. This phenomenon implies that ecosystem or environmental services provided by greenery tend to decrease as the space is urbanized, and challenges arise from the perspective of the difficulties in finding green space or free space to use as GI.

Different methods have been identified to find potential empty, free, or underutilized spaces within the built environment, in private or public areas, to be repurposed as GI. The most common methods and tools found in the literature to find potential spaces include multi-scale Geographic Information Systems (GIS) analyses [12,13], with a multicriteria approach [14], or methodologies of space assessment with the involvement of stakeholders and public participation [2]. Other methods include mixed GIS with satellite image analysis [8,9], and geographic object-based image analysis [6]. To find potential spaces, other methods include the green building framework, where facades and roofs are considered to fulfill green space requirements [15,16] also inventories of vacant lots [17], roadside allocation [18], and accessibility analysis [19] have been developed to assess this issue.

The need to find potential space for GI implementation is not trivial. The methods mentioned above were developed to identify spaces where the benefits of GI could emerge. Such environmental benefits, in general, are related to biodiversity services such as the support of avian biodiversity [18], temperature regulation [18,20], and water purification [21]. GI implementation also bring health benefits (e.g., noise and pollution reduction) [22], mental restoration, stress reduction, and emotional wellbeing [22–25], and behavioral changes related to more active lifestyles [19,24].

Extensive services have been found to be provided by GI. The revision developed by Wang and Banzhaf [26] summarizes these services and show that the most commonly studied functions of GI include regulation of water runoffs, temperature control, amenity provision, and recreational services. Specific examples of such services can be found in the literature. For instance, Karteris et al. [6] estimated the potential of carbon sequestration provided by GI. The authors also studied the potential of rainwater retention and drainage improvement associated with the implementation of GI. The perspective focusing on water and runoff managemen<sup>t</sup> has also been studied by Grunwald et al. [27], Jiménez et al. [13], and Meerow and Newell [14]. Another service associated with GI provision is the control of urban temperature. For example, Anguluri and Narayanan [8] and Grunwald et al. [27] focused their studies on thermal climate and comfort, whereas Meerow and Newell [14] and Norton et al. [9] studied the potential reduction of the heat island effect in the presence of GI. Water and air quality improvement is another example of services provided by GI [13], as is the preservation of urban biodiversity related to the availability of green space and landscape connectivity [14,27].

Additional services provided by the GI include social benefits such as inclusion and civic engagement, recreation and psychological services [18,28,29], and aesthetic enjoyment and education [1]. Besides, economic benefits mainly comprise property value enhancement [30–32], goods and food production [18,33,34], and they attract a skilled workforce [22]. The reduction of social vulnerability and increased access to green space [14] are other examples of these services. Given these general benefits, it could be assumed that GI reconciles the city with its ecosystem and addresses sustainability and resilience goals [35,36].

Urban GI provides important services that result in benefits for everyone. People demand better air quality, sufficient water, safe places to live, and beautiful landscapes. The concern in cities might be to provide livable, safe, and healthy places, and to enhance walking and biking. State and federal agencies, on the other hand, are concerned with water quality, flood control, urban heat island effect (climate and radiation regulation), health, equity, and general welfare. Finding space for GI and its installation is simultaneously a measure to adapt urban areas to climate change [20], to reduce ecological footprints, to close inequity gaps, and to improve people's quality of life. Table 1 summarizes the many benefits derived from constructing green infrastructure in the built environment, grouped by environmental service.


**Table 1.** Benefits of constructing green infrastructure (GI), grouped by environmental service.
