Green spaces have positive effects on human well-being and quality of life in cities. So far, studies in this field mainly compared preferences for, and outcomes of contact with, natural vs. built environments. Less attention has been given to the study of the psychological effects of contact with green spaces differing in their degree of naturalness. This paper thus aims at understanding the relation between ecological (e.g., level of naturalness) and psychological factors (e.g., perceived restorativeness) in shaping evaluations of different urban and peri-urban green spaces. Five typologies of green space have been identified in the city of Bari (southern Italy), ranging from minimum (i.e., high level of man-made elements) to maximum levels of naturalness (i.e., low level of man-made elements). A set of pictures of the different urban green space typologies was shown to fifty undergraduate students of the University of Bari, and then measures of perceived restorativeness were taken. Results show that perceived restorativeness is the highest in peri-urban green spaces, and increases significantly as a function of the level of naturalness.

Research on restorative environments has showed the healthy outcomes of nature experience, though often by comparing attractive natural to unattractive built environments. Some studies indeed showed the restorative value of artistic/historical settings. In a quasi-experimental study involving 125 participants in Rome, Italy, a natural and a built/historical environment, both scoring high in restorative properties, were evaluated in a natural, built/historical, or neutral setting. In accordance with the Biophilia hypothesis and the Attention Restoration Theory (ART), we hypothesized: a higher restorative potential of nature also when compared to built/historical environments; a moderation effect of on-site experience on perceived restorative potential (PRP) of both environmental typologies; higher levels of restorative properties of the environment for on-site vs. not on-site respondents; and a mediation effect of the restorative properties of the environment in the relationship between time spent on-site and PRP. Results supported the hypotheses. In addition, different psychological processes leading to restoration emerged for the natural and the built/historical environment. Theoretical implications for ART and practical applications for an integrative urban design with natural and historical elements are discussed.