Abstract
There is an increasing awareness that besides green spaces, blue spaces can also positively\ud influence mental as well as physical health (see for example, Völker & Kistemann, 2011; Gascon et\ud al., 2017). Blue spaces are: “outdoor environments – either natural or manmade – that prominently\ud feature water and are accessible to humans either proximally (being in, on or near water) or\ud distally/virtually (being able to see, hear or otherwise sense water)” (Grellier et al., 2017, p. 3).\ud Examples include coasts, lakes, ponds and pond systems, wadis systems, artificial buffer basins\ud and water courses. Together with green spaces they form the green-blue infrastructure. Therefore,\ud a second systematic review focused on effects of blue spaces on mental health.