Page - 196 - in Biodiversity and Health in the Face of Climate Change

196 9.3.1.8 Mediation Analyses Mediators were explored in 3 studies (Carrus et  al. 2015; Foo 2016; Marselle et  al. 2016). Investigated mediators fell within two of the three domains mentioned by Markevych et  al. (2017): ‘restoring capacities’ (perceived restorativeness (Carrus et  al. 2015; Foo 2016; Marselle et  al. 2016)) and ‘building capacities’ (physical activity and social interaction (Foo 2016)). ‘Reducing harm’ mediators  were not investigated in these studies. Perceived restorativeness was found to mediate the relationship between biodiversity of green space and general well-being (Carrus et  al. 2015), and between perceived bird species richness and positive affect, happi- ness and negative affect (Marselle et  al. 2016). Perceived bird species richness  also had an indirect effect on positive affect and happiness via the restorative compo- nents of being away, fascination and compatibility, and an indirect effect on nega- tive affect via compatibility (Marselle et  al. 2016). Foo (2016) conducted path analyses to determine how spending time in forest environments with different lev- els of biodiversity influenced mental health and general well-being. Multiple medi- ating pathways were found; time spent in a forest environment with intermediate or high biodiversity engendered a sense of being away, which was positively associ- ated with a change in mood, which then was related to mental health. In only the high biodiverse forest was mental health related to general well-being. In the inter- mediate biodiverse forest, physical activity mediated the relationships between being away and mental health and general well-being. Social interaction did not mediate the effect of a forest environment on either outcome. 9.3.2 Synthesis of  the  Results from  the  Combined Published Literature on  Biodiversity and  Mental Health and  Well- being Relationships A combined set of 24 studies were included in the synthesis of results pertaining to the influence of biodiversity and mental health and well-being: 15 of the 16 recently published studies identified through our search process and nine of the 16 studies identified in Lovell et  al. (2014). Fourteen of these 24 studies reported one or more positive associations between biodiversity and mental health or well-being outcomes (Carrus et  al. 2015; Cox et  al. 2017; Cracknell et  al. 2017; Dallimer et  al. 2012; Foo 2016; Fuller et  al. 2007; Huby et  al. 2006; Johansson et  al. 2014; Jones 2017; Luck et  al. 2011; Marselle et  al. 2016; Rantakokko et  al. 2018; Wheeler et  al. 2015; White et  al. 2017; Wolf et  al. 2017) (see Table  9.4). Seventeen of the 24 studies reported one or more results with no significant relationship (Annerstedt van den Bosch et  al. 2015; Annerstedt et  al. 2012; Björk et  al. 2008; Cox et  al. 2017; Cracknell et  al. 2016, 2017; Dallimer et  al. 2012; de Jong et  al. 2012; Duarte-Tagles et  al. 2015; Fuller et  al. 2007; Grahn and Stigsdotter 2010; Jorgensen et  al. 2010; Marselle et  al. 2015, 2016; Rantakokko et  al. 2018; Saw et  al. 2015; Wolf et  al. 2017). Two studies reported one or more negative associations between biodiversity and mental health or well-being outcomes (Dallimer et  al. 2012; Marselle et  al. 2015) (Table  9.4). M. R. Marselle et al.