Connecting Global Priorities Biodiversity and Human Health

3. Biodiversity, green space,
exercise and health
The relationships between biodiversity and
good physical health are inherently complex and
multidimensional, with multiple confounding
and interrelated sociocultural, geographical and
economic mediators. The studies that exist often
fail to provide clear empirical evidence of the
effects of biodiversity on physical health and wellbeing.
While the majority of studies presented
herein are examples of where a potential positive
association between biodiversity and physical
health could be inferred, a large number of
studies also report inconclusive results (Lovell et
al. 2014) and some report inverse relationships
(Huynen et. al 2004; Dallimer et al. 2012).
Further multidisciplinary study is needed to more
clearly establish causal links to inform policy.
Current analyses are methodologically diverse
and frequently focus only on urban and western
settings that are insufficiently interdisciplinary
to test postulated relationships. Research needs
to have adequate involvement of the expertise
and standard methodological practices of
the social sciences (including psychology and
sociology), health sciences (including physiology
and epidemiology) and environmental sciences
(particularly ecology), rather than be dominated by
selected disciplines, as is so often the case. In the
few studies in which a direct causal relationship
between biodiversity and physical and mental
health has been sought, it is frequently the case
that precise physiological elements of physical
health have not been correspondingly measured.
With notable recent exceptions, including those
noted above, few studies rigorously measure both
biodiversity and specific physiological effects on
physical health. In addition, the evidence we have
is from mostly affluent urban Western societies,
and further exploration across a range of cultures,
geographical regions and socioeconomic groups
is needed, including rural and developing world
settings.
3.1 Biodiversity, recreation and
“Time spent directly experiencing and interacting with
nature (a problematic term to define) has been shown
to improve psychological health and well-being, as well
as increase physical activity levels…” (Pretty et al. 2008).
As human societies industrialize and urban centres
continue to expand, the physical relationship
with biodiversity sometimes shifts from a direct
consumptive interaction to one of more abstracted
recreational and leisure activity (Keniger et al.
2013). Regardless of our socioeconomic status,
setting or motivations of subsistence or leisure,
our exposure to and interactions with biodiversity
range from passive engagement from afar (e.g.
viewing through a window) to being within
a natural space (e.g. sitting in a park), to the
direct active engagement of fishing, hunting or
gardening. Much of our current body of evidence
documenting the health effects of exposure to
natural biodiverse environments is gleaned from
urban, Western, developed world settings (Lovell
et al. 2014; for a recent review, see Townsend
et al. 2015). While biodiversity has rarely been
measured directly in these studies, they do provide
emerging evidence that interacting with natural
surroundings in urban settings can deliver a
range of measurable benefits (Bauman 2004;
Brown et al. 2007; Blair & Morris 2009), including
positive effects on physical health (Berger & Motl
2000; Street et al. 2007; Rethorst et al. 2009),
psychological well-being (Barton & Pretty 2010;
Kaplan & Kaplan 1989; Kaplan 1995), cognitive
ability (Ulrich 1983) and social cohesion (Maas et
al. 2006). Conversely, there is empirical evidence
at a global scale that more biodiverse settings
correlate with poorer health outcomes (Huynen
et. al 2004) and on a local scale, some self-reported
measures of well-being are inversely related with
natural biological diversity (Dallimer et al. 2012).
While interacting with nature can deliver health
benefits, the converse is also true and the specific
role of biodiversity in effecting these health
outcomes is still not well understood.
It is clear that exercise and physical activity have
positive impacts on health. Physical activity has
been shown to lead to improved physical fitness
Connecting Global Priorities: Biodiversity and Human Health
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