Connecting Global Priorities Biodiversity and Human Health

al. (2012) and Fuller et al. (2007) also showed that
bird species richness was positively associated with
measures of well-being, while butterfly species
richness was not shown to have any association.
Fuller et al. (2007) found that enhanced well-being
was positively related to increased plant species
richness, whereas Dallimer et al. (2012) showed
a decline in well-being under such conditions.
Variation was also seen in relation to tree cover,
with Dallimer et al. (2012) reporting a positive
relationship with well-being and Fuller et al. (2007)
finding no association. Local-scale urban studies
on the links between biodiversity in green leisure
spaces and self-reported well-being do suggest that
exposure to biodiversity may have demonstrable
positive impacts on health (Dallimer et al. 2012;
de Jong et al. 2012; Fuller et al. 2007; Tilt et
al. 2007), although without understanding the
specific effected aspects of physiological health.
These variations may in part be explained by
differing cultural contexts, and even by differences
in how various groups within a community value
their local landscapes, biodiversity or green spaces.
Such perspectives may in part be informed by
socioeconomic factors, or by the degree to which
different groups feel they can influence local
decision-making affecting their environment (see,
for example, Cutts et al. 2009; Ernstson 2013).
Some studies do measure sets of physiological
indicators of physical health in relation to natural
green space but do not measure biodiversity within
these natural settings. There is a growing body of
evidence to suggest that interactions with nature
can alleviate some of the negative physiological
effects of stress within urban environments. A
study from the Netherlands showed that outdoor
gardening led to significantly greater reduction in
the stress hormone cortisol than indoor reading
(Van den Berg & Custers 2011). This study cannot,
however, determine the relative importance of
the activity associated with the gardening and
the natural components of the environment (e.g.
biodiversity) in promoting stress reduction. Some
studies have concluded that the physiological
effects of stress are reduced in forest environments
and other natural environments.⁵ For example, a
Swiss study also found that a decrease in stressinduced
headaches was significantly related to
physical activity in parks (Hansmann et al. 2007).
Other physiological benefits that have been
studied are the relationships between natural
spaces and healing. In a study of cholecystectomy
patients in the US, postoperative healing time was
significantly reduced for patients in a hospital room
with a window view of nature in comparison with
patients with a view of a brick wall (Ulrich 1984).
Patients with a view of trees also required fewer
painkillers, received fewer negative evaluative
comments from nurses and had fewer postsurgical
complications. Another study demonstrates that
outdoor therapeutic camping trips reduce the
probability of relapse among recovering substance
abusers (Shin et al. 2001).
Physiological responses to nature have also
been shown to vary according to gender. A UK
study shows that cardiovascular and respiratory
disease mortality rates among men decreased
with increasing green space, with no significant
relationship for women (Richardson and Mitchell
2010). Ulrich (1981) found that the positive
physiological responses of exposure to nature,
as measured by heart rate and alpha amplitude
while viewing images of nature, were significantly
stronger for women.
Studies on the effects of indoor plants in office
and classroom environments have also shown that
their presence can improve physical health (Fjeld
et al.1998) and reduce the occurrence of illness
(Han 2009; Bringslimark et al. 2007).⁶ As with
⁵ A Chinese experimental study (Yamaguchi et al. 2006) measured stress in healthy males before and after exercise in both a
forest and an urban environment using salivary amylase activity as a physiological indicator. Enzyme activity significantly
reduced after exercise in forest environments.
⁶ A Norwegian study showed that the presence of plants in offices correlated with a reduction in dry skin, hoarse throat,
coughing and fatigue, suggesting that the introduction of foliage plants into an indoor environment may reduce symptoms
of physical discomfort and improve health (Fjeld et al. 1998). Related studies on the effects of indoor vegetation have found
that the diversity and presence of indoor plants in an office (Bringslimark et al. 2007) and a classroom (Han 2009) reduce
the occurrence and frequency of time taken off due to ill health.
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