Seite - 383 - in Biodiversity and Health in the Face of Climate Change

383 included increased physical activity, reduced exposure to air and noise pollution, and psychological relaxation. However, the mechanisms through which urban  green space impacts climate change are much less understood. To address the gaps in our understanding on the effectiveness of urban green space interventions, the WHO Regional Office for Europe gathered experts on green space and urban planning to discuss approaches to and experiences with urban green space interventions. Based on a review of international research evidence and a compilation of European case studies (WHO Regional Office for Europe 2017), the expert meeting addressed the variety of green space intervention approaches and their related impacts on environmental conditions, health status, social and mental well-being, and equity. This chapter outlines the findings from this research, high- lighting aspects to be considered when designing and evaluating urban green space interventions that aim to maximize environmental, social and health benefits and to address equity issues. 17.2 Urban Green Space Interventions 17.2.1 What Are Urban Green Space Interventions? Urban green spaces are considered to be urban spaces covered by vegetation of any kind. This includes smaller green space features (such as street trees and roadside vegetation), green spaces not available for public access or recreational use (such as green roofs and facades, or green space on private grounds), and larger green spaces that provide various social and recreational functions (such as parks, playgrounds or greenways). Urban green space interventions are defined as urban green space changes that significantly modify green space availability and features by creating new green space, changing or improving existing green space, or removing or replacing green space. The use of the term ‘urban green spaces’ should not be considered to conflict with other commonly used terms and definitions, such as ‘green infrastructure’, ‘green corridors’ or ‘public open space’, which tend to be applied in urban and regional planning. On the basis of the evidence review, four main categories of urban green space interventions were identified: 1. Park-based: Involve change to the physical environment only, or use a dual approach combining a change to the physical environment with programming or marketing events in order to promote use of parks. 2. Greenways/trails: Development of new greenways (typically continuous linear corridor of green space facilitating walking, cycling and other activities) and walking/cycling trails, or the modification of existing greenways or walking/ cycling trails, for example, through the addition of signage, or using a dual approach (see above). 17 Environmental, Health and  Equity Effects of  Urban Green Space Interventions