Where to construct new urban green spaces to be at the recommended distance from users and to complement existing ones? A study in five cities of northern Portugal

The proximity to urban green spaces (UGS) is important to facilitate their use by citizens, mainly by the most vulnerable groups in society who are usually unable to walk long distances. Furthermore, there are several ecosystem services from which the population can only benefit if UGS are close. In addition to being important to identify areas without a UGS nearby, it is also important to indicate possible locations for a new UGS, thus avoiding wasting resources by overlapping coverage areas or leaving gaps in coverage. It is also important to understand among all possible locations where the construction of a UGS is most needed. The present study aims (i) to identify possible locations for future UGS and order them by construction priority, (ii) to develop and test a methodology for decision-makers and urban planners and (iii) to contribute to increasing and developing UGS in cities. Considering residential areas, the results reveal a deficiency in UGS coverage in all the cities studied, as only 43.86–57.09% of residential areas have a UGS within 300 m. Construction of proposed UGS will lead to a 12.30–26.15% increase in coverage. The proposed methodology needs further improvement, but it can be a valuable tool for urban planners and decision-makers, and can encourage the construction of more UGS.