Green Infrastructure Evidence Base

3 Human Health and Well-being

Sections

Green Infrastructure

Green Infrastructure is the network of green spaces and water systems that delivers multiple environmental, social and economic values and services to urban communities. This network includes parks and reserves, backyards and gardens, waterways and wetlands, streets and transport corridors, pathways and greenways, farms and orchards, squares and plazas, business and instituional green areas, roof gardens and living walls, sports fields and cemeteries. Green Infrastructure is critical to the health, liveability and sustainability of urban environments. It strengthens the resilience of towns and cities to respond to the major current and future challenges of growth, health, climate change and biodiversity loss, as well as water, energy and food security.

3.2 Overview

3.2.1 Definition of terms

The following section summarizes the main terms used by researchers and practitioners, often drawn from different disciplines.

Health. The most widely referenced definition of health is that of the WHO which defines health as ‘a state of complete physical, mental and social well-being and not merely the absence of disease or infirmity’ (World Health Organization, 1946).

Well-being has been described as not just the benefits gained from good psychological and physical health, but also related to specific aspects such as favourable thoughts and feelings, satisfaction with life, ability to be self-sufficient and pro-active, possessing a sense of happiness, and a positive evaluation of one’s life in a general sense (Diener et al., 1999).

Nature. (Maller et al., 2006) defines nature as referring to ‘any single element of the natural environment (such as plants, animals, soil, water or air), and includes domestic and companion animals as well as cultivated pot plants’. Researchers also subdivide nature into different categories, for example the (Health Council of the Netherlands, 2004) nominates the following:

  • Urban nature: nature in an urban setting (e.g. gardens, parks).
  • Agricultural nature: primarily agricultural landscape with small, dedicated patches of nature.
  • Natural forests: nature in ‘woodlands’ where management emphasizes more authentic vegetation.
  • Wild nature: nature in an environment that develops spontaneously and can be maintained with minimal management (e.g. natural rivers, woodlands etc.).

(Planet Ark, 2012) summarizes the different interactions between people and ‘nature’ studied by a range of researchers into human health and well-being:

  • Nature views: the ‘naturalness’ of views, refers to people encountering nature by observing it, for example, through a window (a passive type of interaction)
  • Technological nature: simulations or representations of nature by technological means, such as videos of natural environments (Kahn Jr et al., 2009)
  • Nearby nature: parks or other natural areas that are conveniently accessible to children and others, from their homes or schools
  • Wild nature: more remote wilderness or bush settings. ‘Wild nature activities’are those that occur in such settings, such as hiking, camping, playing in nature reserves, or participating in conservation activities
  • Domesticated nature: more designed or controlled parks or settings, such as suburban parks, kitchen gardens in schools, and even indoor pot plants. Domesticated nature can also include interaction with animals, such as pets. ‘Domesticated nature activities’include planting trees or seeds, and caring for plants, and picking flowers or produce

Virginia Lohr (2011) of the Department of Horticulture and Landscape Architecture at Washington State University provides a useful overview of the many studies which have documented the wide range of positive effects of plants on people, published by researchers in horticulture, landscape architecture, environmental psychology, medicine, and many other fields. According to Lohr p.159:

‘Plants are essential for our survival, provide food, fibre, building material, fuel, and pharmaceuticals. Plants also produce intangible benefits for people, such as improving our health. These benefits occur with scenes of nature, individual plants indoors, gardens outdoors, parks, and forests. The understanding of the role of trees, in particular, in promoting both human and ecological health is increasing. Plants make our surroundings more pleasant, and they help us feel calmer. They contribute to cleaner, healthier air, thus improving our well-being and comfort. Plants have been associated with reduced stress, increased pain tolerance, and improved mental functioning in people. Human responses to plants appear to be both learned and innate. Some studies suggest genetic components to the responses. Some primates are known to detect subtle differences in leaf colour, selecting to eat those leaves with the highest nutritive value; people also respond more positively to plants of some colours than to others. Most people in the world now live in urban areas. These areas are typically devoid of plants, resulting in concerns over children being raised in such unnatural areas’.

3.2.2 Existing literature reviews

In recent years researchers have undertaken a number of literature reviews on the linkages between human health and well-being and urban nature or the design of the ‘built environment’ (including landscapes). (Pretty, 2004) conducted a literature review of the contributions of nature to mental and physical health, and found a strong correlation between people being in or viewing nature, and feeling healthier. A comprehensive review of the relationship between nature and health was undertaken by (Grinde and Patil, 2009). The review of 50 articles examined the health benefits associated with mere visual contact with nature and concluded that an environment devoid of nature has a negative effect on health and quality of life. In 2010 Abraham et al. carried out a scoping study reviewing over 120 studies examining the health-promoting aspects of natural and designed landscapes (Abraham et al., 2010). The authors concluded that:

‘Landscapes have the potential to promote mental well-being through attention restoration, stress reduction, and the evocation of positive emotions; physical well-being through the promotion of physical activity in daily life as well as leisure time and through walkable environments; and social well-being through social integration, social engagement and participation, and through social  support and security’ p.59.

As shown on Figure 12 the study identified three dimensions of human health linked to Green Infrastructure:

  • Mental well-being: landscape as a restorative environment
  • Physical well-being: walkable landscapes
  • Social well-being: landscape as a bonding structure

Figure 12: Green Infrastructure and well-being. Adapted from Abraham, Sommerhalder et al. (2010).

Mental well-being was found to include:

  • Attention restoration and recovery from metal fatigue
  • Recovery from stress
  • Positive emotions

Physical well-being was found to include:

  • Physical outdoor activity in cities
  • Physical outdoor activity outside cities

Social well-being was found to include:

  • Social integration
  • Collectively experiencing nature

The authors concluded that their scoping study showed ‘strong additional and new support for understanding landscapes as a health resource and health determinant’ (Frumkin, 2003; Maller et al., 2006). The relationship between landscape and health was found to show two main features:

  • First, health-promoting landscapes contribute to healthy lifestyles in terms of physical activity and mental and emotional relaxation
  • Second, health-promoting landscapes promote the acquisition of resources for health such as social support, concentration and emotional stability

Table 1 presents the findings of the literature review by Abraham et al. on the health-promoting influences of landscape on a range of health dimensions.

Table 1: Overview of the literature on the health-promoting influence of landscape

Source: Abraham, Sommerhalder et al. (2010) p.62-63

Health dimension

 

Health-promoting

landscape effect

Landscape character-
-istics

Study design

Author(s)

Mental well-being

Attention restoration and recovery from mental fatigue

Natural landscapes such as beaches, waters, forests, parks, mountains

Availability of public open spaces used for public entertainment and sports

Conceptual accounts / literature reviews

Health Council of the Netherlands (2004); Frumkin (2003); Frumkin (2001); Kaplan, (1995a); Kaplan, (1995b); Kaplan and Kaplan, (1989); Maller et al. (2006).

Survey-studies (cross-sectional studies, longitudinal studies)

Herzog et al. (1997); Korpela and Hartig (1996); Korpela et al. (2001); Tennessen and Cimprich (1995)

Experimental studies

Berto (2005); Hartig et al. (1996, 2003); Kuo (2001);Staats and Hartig (2004); Staats et al. (2003)

Recovery from stress

Landscape perceived as pleasant, i.e. landscape contains visual stimuli such as moderate complexity and richness of natural elements like waters or vegetation

Easy access to green areas with lower sound levels from road traffic

Conceptual accounts / literature reviews

Frumkin (2001); Health Council of the Netherlands(2004); Maller et al. (2006)

Survey-studies (cross-sectional studies, longitudinal studies)

Gidlo¨f-Gunnarsson and O¨ hrstro¨m (2007)

Experimental studies

Hartig et al. (1996, 1999, 2003); Laumann et al. (2003); Parsons et al. (1998); Ulrich et al. (1991, 2003)

Positive emotions

Landscape perceived as pleasant

Open and accessible forests

Perceived amount of open space and vegetation (urban landscapes)

Survey-studies (cross-sectional studies, longitudinal studies)

Herzog and Chernick (2000); Kaplan (2001); Korpela et al. (2002); Kuo and Sullivan (2001b); Kuo et al. (1998)

Experimental studies

Cackowski and Nasar (2003); Kuo and Sullivan (2001a); Staats et al. (1997)

Qualitative studies

Milligan and Bingley (2007)

Physical wellbeing

 

Physical outdoor activity in cities

Daily life:

Access to and presence of physical activity-promoting facilities

General functionality of urban districts (e.g., sidewalks, traffic regulation, bicycle and walking paths)

Leisure time:

Land-use-mix

Street connectivity

Traffic safety (e.g. pedestrian zones)

Aesthetically appealing landscapes

Trust in neighbours, active neighbours

Nearby parks, playgrounds and sport fields

Access to places for physical activities

Conceptual accounts / literature reviews

Frank and Engelke (2001); French et al. (2001);Frumkin (2003); Frumkin et al. (2004); Health Council of the Netherlands (2004); Kaspar and Bu¨hler (2006); McCormack et al. (2004); Pikora et al. (2003); Popkin et al. (2005);Powell (2005); Sallis and Glanz (2006)

Survey-studies (cross-sectional studies, longitudinal studies)

Addy et al. (2004); Ball et al. (2001); Booth et al. (2000); Cervero and Duncan (2003); Craig et al. (2002); iles-Corti and Donovan (2002); Gordon-Larsen et al. (2006); Humpel et al. (2004a ,b); Lee et al. (2001); Leslie et al. (2005);Li et al. (2005);Neff et al. (2000); Ozguner and Kendle (2006);Payne et al. (2002); Pikora et al. (2006); Saelens et al.(2003); Titze et al. (2005); Wendel-Vos et al. (2004)

Qualitative studies 

Coen and Ross (2006); Eyler et al. (1998); Wilbur et al.(2002)

 

Physical outdoor activity outside cities

 

Aesthetically appealing rural green landscapes (e.g. forests)

Conceptual accounts / literature reviews

Gasser and Kaufmann-Hayoz (2004)

Survey-studies (cross-sectional studies, longitudinal studies)

Baur and Gilgen (1999); Swiss Federal Office for the Environment (1999); Lamprecht and Stamm (2002);Marti et al. (2002);Pretty et al. (2005a)

Experimental studies

Pretty et al. (2005b)

Social well-being

Social integration

Parks

Community gardens

Sufficient level of safety, attractive, walkable, serve multiple purposes

Rich in vegetation

Conceptual accounts / literature reviews

Brown and Jameton (2000); Frumkin (2003); Frumkin et al. (2004); Hancock (2001); Health Council of the

Netherlands (2004); Maller et al. (2006); Twiss et al.(2003)

Survey-studies (cross-sectional studies, longitudinal studies)

Armstrong (2000); Booth et al. (2000); Kuo et al. (1998); Kweon et al. (1998);Leyden (2003); Seeland and Ballestros (2004);Stigsdotter and Grahn (2004); Sullivan et al. (2004);Waliczek et al. (2005)

Experimental studies

Doyle and Krasny (2003)

Qualitative studies

Baum and Palmer (2002); Irvine et al. (1999); Milligan et al. (2004); Rishbeth and Finney (2006); Wakefield et al. (2007)

Collectively experiencing nature

 ‘‘Wild’’ nature

Survey-studies (cross-sectional studies, longitudinal studies)

Ewert (1991)

Experimental studies

Staats and Hartig (2004)

Qualitative studies

Fredrickson and Anderson (1999); Pohl et al. (2000); Sharpe (2005)

 

A number of more local literature reviews and scoping studies have been conducted in Australia by Mardie Townsend and others as part of the NiCHE Research Team (Nature in Community, Health and Environment) at the School of Health and Social Development, Deakin University, Melbourne. A study published in 2002 Healthy Parks Healthy People: The Health Benefits of Contact with Nature in a Park Context reviewed literature on the multiple health benefits of viewing or interacting with nature in parks (Maller et al., 2002). In a 2006 paper Maller (Maller et al., 2006) presented a review of the literature (empirical, theoretical and anecdotal) on the human health benefits of contact with nature, focusing on ‘everyday’ interactions with nature in a park setting by urban populations including: (1) viewing natural scenes; and (2) being in natural environments. Table 2 summarizes the evidence cited by the authors supporting the assertion that contact with nature promotes health and well-being.

Table 2: Summary of evidence supporting the assertion that contact with nature promotes health and well-being. Adapted from Maller, Townsend et al. (2006) p.50.

What the Research Demonstrates With Certainty

Assertion

Key References

There are some known beneficial physiological effects that occur when humans encounter, observe or otherwise positively interact with animals, plants, landscapes or wilderness.

Friedmann et al. (1983a); Friedmann et al. (1983b); Parsons (1991); Ulrich et al.(1991b); Rohde and Kendle (1994); Beck and Katcher (1996); Frumkin (2001)

Natural environments foster recovery from mental fatigue and are restorative.

Furnass (1979); Kaplan and Kaplan (1989); Kaplan and Kaplan (1990); Hartig et al. (1991); Kaplan (1995)

There are established methods of nature-based therapy (including wilderness, horticultural and animal-assisted therapy among others) that have success healing patients who previously had not responded to treatment.

Levinson (1969); Katcher and Beck (1983); Beck et al., (1986); Lewis (1996); Crisp and O’Donnell (1998); Russell et al. (1999); Fawcett and Gullone (2001); Pryor (2003)

When given a choice people prefer natural environments (particularly those with water features, large old trees, intact vegetation or minimal human influence) to urban ones, regardless of nationality or culture.

Parsons (1991); Newell (1997); Herzog et al. (2000)

The majority of places that people consider favourite or restorative are natural places, and being in these places is recuperative.

Kaplan and Kaplan (1989); Rohde and Kendle (1994); Korpela and Hartig (1996); Herzog et al. (1997); Newell (1997); Herzog et al. (2000)

People have a more positive outlook on life and higher life satisfaction when in proximity to nature (particularly in urban areas).

Kaplan and Kaplan (1989); Kaplan (1992a); Lewis (1996); Leather et al. (1998); Kuo (2001); Kuo and Sullivan (2001)

Exposure to natural environments enhances the ability to cope with and recover from stress, cope with subsequent stress and recover from illness and injury.

Ulrich, (1984); Parsons (1991); Ulrich et al. (1991b)

Observing nature can restore concentration and improve productivity.

Tennessen and Cimprich (1995); Leather et al. (1998); Taylor et al. (2001)

Having nature in close proximity, or just knowing it exists, is important to people regardless of whether they are regular ‘users’ of it.

Kaplan and Kaplan (1989); Cordell et al. (1998)

 

In a study undertaken for Beyond Blue, (Townsend and Weerasuriya, 2010) of Deakin University reviewed a large body of literature which demonstrates the many benefits of contact with nature for mental health and well-being. In 2011 Townsend of Deakin University also conducted a Health Indicators Project, a review of the benefits of urban forests, as part of the City of Melbourne Urban Forest Project (Townsend and Sick, 2011). The study included a review of published literature and research reports providing evidence of urban forest benefits (including urban ecology, biodiversity, community engagement, and human health and wellbeing). The study also identified indicators for measuring the impacts of urban forests on natural processes (including air and water quality, and thermal comfort) and on human health and wellbeing (including physical and mental health, and social connectedness). The study investigated:

a) Links between urban forest and ecosystem health:

a. Urban Heat Island effect
b. Air quality
c. Noise reduction
d. Carbon sequestration
e. Biodiversity

b) Links between urban forest and human health:

a. Air quality and health
b. Noise pollution and health
c. Biodiversity and health
d. Physical activity and health
e. General health and wellbeing
f. Mental wellbeing
g. Social cohesion and health
h. Economic wellbeing

c) Strategies for measuring/indicators of impacts of urban forest:

a. Measuring impacts on natural processes:

i.Temperature
ii.Air pollution

b. Measuring impacts on human health and wellbeing:

i. General physical and mental health
ii.Heat related health issues
iii.Air quality related health issues
iv.Noise pollution related health effects
v.Social capital related health issues

Two recent studies commissioned by Planet Ark have investigated links between nature and children’s physical and psychological health. A 2011 study, Climbing Trees: Getting Aussie Kids Back Outdoors, investigated childhood interaction with nature and how this interaction is changing between generations (Planet Ark, 2011).The study included both a literature review and survey research, and found a significant decline in outdoor interaction with nature in just one generation.A 2012 study Planet Ark Planting Trees reviewed literature on the ‘intellectual, psychological, physical and mental health benefits of contact with nature for children’ (Planet Ark, 2012). A review of local and international research in this field revealed an emerging body of evidence that ‘contact with nature during childhood could have a significant role to play in both the prevention and management of certain physical and mental health problems, and in forming environmentally responsible attitudes in future adulthood’. The study also included attitudinal research into how Australians perceive the link between nature and children’s health, wellbeing and development.

Another recent literature review was conducted by Australian researchers at the Healthy Built Environments Program, City Futures Research Centre at the University of New South Wales (Kent et al., 2011). The study examined research evidence demonstrating links between the built environment (including landscapes) and human health. The study addressed three of the major risk factors for contemporary chronic disease: physical inactivity, social isolation, and obesity. The focus of the review was on the key built environment interventions that support human health, which were identified as:

  • The Built Environment and Getting People Active
  • The Built Environment and Connecting and Strengthening Communities
  • The Built Environment and Providing Healthy Food Options

In the UK, (Lee and Maheswaran, 2010) undertook a literature review of studies dealing with the health effects of green space.The authors concluded that there is only ‘weak’ evidence for the links between physical and mental health and well-being, and urban green space. Environmental factors such as the quality and accessibility of green space are known to affect its use for physical activity. User determinants (such as age, gender, ethnicity and the perception of safety) are also important. However the authors found that many studies were limited by poor study design, failure to exclude confounding factors, bias, reverse causality, and weak statistical associations. The authors concluded that;

‘…most studies reported findings that generally supported the view that green space has a beneficial health effect. Establishing a causal relationship is difficult, as the relationship is complex. Simplistic urban interventions may therefore fail to address the underlying determinants of urban health that are not remediable by landscape redesign’ p.212.

Other evidence suggests that contact with nature is particularly important in highly urbanised environments (Beer et al., 2003; Nielsen and Hansen, 2007; Hartig, 2008; Maller et al., 2010) and smallscale encounters with nature and people within natural settings appear to be equally as significant to health as access to large areas of natural open space.

In a recent paper (Keniger et al., 2013) reviewed research into the ‘benefits of interacting with nature’. A qualitative review was undertaken of 57 studies published in peer-reviewed scientific journals. The researchers discovered that evidence for the benefits of interacting with nature is geographically biased towards high latitudes and Western societies, potentially contributing to a focus on certain types of settings and benefits. Social scientists have been the most active researchers in this field. Contributions from ecologists are few in number, perhaps hindering the identification of key ecological features of the natural environment that deliver human benefits. Although many types of benefits have been studied, benefits to physical health, cognitive performance and psychological well-being have received much more attention than the social or spiritual benefits of interacting with nature, despite the potential for important consequences arising from the latter. The evidence for most benefits is correlational, and although there are several experimental studies, little as yet is known about the mechanisms that are important for delivering these benefits. For example, we do not know which characteristics of natural settings (e.g., biodiversity, level of disturbance, proximity, and accessibility) are most important for triggering a beneficial interaction, and how these characteristics vary in importance among cultures, geographic regions and socio-economic groups. The authors conclude that these are key directions for future research if we are to design landscapes that promote high quality interactions between people and nature in a rapidly urbanising world.

Table 3: Typology of the benefits of interacting with nature. Source: Keniger, Gaston et al. (2013).

Benefit

Description

Examples

Psychological well-being

Positive effect on mental processes

Increased self-esteem

Improved mood

Reduced anger/frustration

Psychological well-being

Reduced anxiety

Improved behaviour

Cognitive

Positive effect on cognitive ability or function

Attentional restoration

Reduced mental fatigue

Improved academic performance

Education/learning opportunities

Improved ability to perform tasks

Improved cognitive function in children

Physiological

Positive effect on physical function and/or physical health

Stress reduction

Reduced blood pressure

Reduced cortisol levels

Reduced headaches

Reduced mortality rates from circulatory disease

Faster healing

Addiction recovery

Perceived health/well-being

Social

 

Positive social effect at an individual, community or national scale

 

Facilitated social interaction

Enables social empowerment

Reduced crime rates

Reduced violence

Enables interracial interaction

Social cohesion

Social support

Spiritual

Positive effect on individual religious pursuits or spiritual well being

 

Increased inspiration

Increased spiritual well-being

Tangible

 

Material goods that an individual can accrue for wealth or possession

 

Food supply

Money

3.2.3 Epidemiological studies

A number of epidemiological studies have been conducted which investigate the links between nature and human health and well-being. Epidemiology can be defined as the study of the patterns of disease or health in well-defined populations, and related causes or influences. Epidemiology is considered to be a cornerstone of public health research and practice, helping inform policy decisions by identifying risk factors for disease and targets for preventive medicine policies. Epidemiological studies are also particularly interesting as they have involved public health and medical researchers in the ecological field.

In one study, (de Vries et al., 2003) explored the relationship between green areas and health in the Netherlands, by combining data on the self-reported health of over 10,000 people with land-use data on the amount of greenspace in their living environments. People living in a greener environment were found to be significantly healthier in all three health indicators (number of symptoms experienced, perceived general health and a score indicating propensity to mental health problems). The positive link between greenspace and health was found to be most apparent among the elderly, ‘housewives’ and people from lower socioeconomic groups. The mechanism linking greenness to health was not studied, however suggested possibilities included a less polluted environment, greater contact with greenspace, or more physical activity. It was also suggested that if greenspace in  living environments actually does make people healthier (rather than just a function of perceived health) then the densification of cities and associated removal of green space may result in unexpected negative health consequences.

A follow up study in the Netherlands investigated the strength of the relation between the amount of green space in people’s living environment and their perceived general health for a population of over 250,000 (Maas et al., 2006). The study also analysed the data for different age and socioeconomic groups and level of ‘urbanity.’ It was found that the percentage of green space inside a one kilometre and a three kilometre radius had a significant relation to perceived general health, and this relationship was generally present at all degrees of urbanity. The overall relation was somewhat stronger for lower socio-economic groups, and the elderly, youth, and secondary educated people in large cities seem to benefit more from the presence of green areas in their living environments than other groups in large cities. The authors concluded that:

‘…the percentage of green space in people’s living environment has a positive association with the perceived general health of residents. Green space seems to be more than just a luxury and consequently the development of green space should be allocated a more central position in spatial planning policy’ p.587.

Other epidemiological studies on mortality rates found that people with access to green places exhibited greater longevity (Tanaka et al., 1996; Takano et al., 2002). Increased survival of older people was found to be significantly linked to the availability of parks and tree lined streets near their home; and having walkable green streets and spaces nearby was a significant predictor for survival over the following five years.

3.2.4 Survey research

A study in the UK examined which aspects of neighbourhood open space are associated with walking for recreation purposes and for transport purposes by older people (Sugiyama and Ward-Thompson, 2008). The study sample consisted of 286 people over 65 year’s old living in Britain who completed a self-administered questionnaire. It was found that pleasantness of open space and lack of nuisance were associated with walking for recreation, while good paths to reach open space and good facilities in open space were conducive to more walking for transport. The study suggests the possibility that enhancing these aspects of neighbourhood open spaces may contribute to active lifestyles of older adults.

A local study collected survey data from 1,895 residents from 32 neighbourhoods in metropolitan Adelaide, to explore relationships between perceived greenness in the environment and mental and physical health (Sugiyama et al., 2008). The researchers found that perceived neighbourhood greenness was more strongly associated with mental health than it was with physical health. Recreational walking seemed to explain the link between greenness and physical health, whereas the relationship between greenness and mental health was only partly accounted for by recreational walking and social coherence. The researchers hypothesised a link to the restorative effects of natural environments. They also concluded that longitudinal studies were needed to further examine the causal relationship between natural environments and health effects.

In another study, a survey of over 11,000 Danes found that the main reason for using green space was to enjoy the weather and fresh air rather than engage in physical activity (Schipperijna et al., 2010). Similarly, research in Zurich Switzerland by (Frick et al., 2007) showed a preference for low stimulus natural areas to promote relaxation and escape, rather than organised physical activity.

3.2.5 Research critique

A number of recent papers have reviewed methodological issues relating to the design of studies which attempt to relate human health and well-being and urban greening.

A recent paper by (Lachowycz and Jones, 2011) reported on a systematic review of quantitative research examining the association between objectively measured access to green-space and physical activity, weight status and health conditions related to elevated weight. Sixty studies were assessed for methodological quality and strength of the evidence. The majority (68%) of papers found a positive or weak association between green-space and obesity-related health indicators, but findings were inconsistent and mixed across studies. Several studies found the relationship varied by factors such as age, socio-economic status and green-space measure. The authors recommended developing a theoretical framework which considers the interactions between different types of green-space. Key areas for future research include investigating if and how people actually use green-space and improving understanding of the mechanisms through which green-space can improve health and, in particular, if physical activity is one such mechanism.

In Japan, recreation activity and relaxation in a forest environments called ‘forest therapy’ or ‘shinrin-yoku’ (forest-air bathing and forest-landscape watching/walking) have become a type of nature therapy popular with urban dwellers experiencing mental stress conditions. The fields of preventive and alternative medicine have also shown an interest in the therapeutic effects of forest therapy. (Kamioka et al., 2012) summarized the evidence for the curative and health enhancement effects of forest therapy and assessed the quality of studies based on a review of randomized controlled trials (RCTs). The authors concluded that there was insufficient evidence due to poor methodology and reporting and the heterogeneity of RCTs, meaning it was not possible to offer any conclusions about the effects of ‘forest therapy’ interventions.  The authors, however did propose a strategy for strengthening study quality.

Townshend, (2012 p.18) provides a thoughtful critique of research linking human health and well-being and urban greening:

‘It is fair to say, however, that research that has tried to unpick the causal pathways between greenness, green space, physical activity and obesity has been inconsistent and many results equivocal. Partly this is because of the complexity of this relatively new arena for research and while a number of studies have been carried out globally, there are many methodological weaknesses and theoretical unknowns’.

Research issues include:

  • Most studies are cross-sectional (while longitudinal studies of influences on weight would be more useful).
  • There is huge variety and inconsistency in the confounding factors the studies take into consideration.
  • More generally there is a lack of consistent methodologies which makes cross comparison of results extremely difficult.
  • Green space and/or greenness have been measured in relatively crude ways (using for example, percentage land-use calculations, distance from individual’s home and/or relatively simple quality assessment).
  • In many studies green space is just one of several environmental factors measured and assessed for their potential influence.
  • Research needs to address three dynamics of green space: green space as location for activity; green space as motivation for activity; and additional benefits (physiological and psychological) from activity in green space over and above what might be expected from alternative locations.

Several recent studies have identified a relationship between the natural environment and improved health outcomes. However, for practical reasons, most have been observational, cross-sectional studies. (Donovan et al., 2013) conducted a ‘natural’ experiment, (aimed to provide stronger evidence of causality to test whether a major change to the natural environment (the loss of 100 million trees to the emerald ash borer, an invasive forest pest) has influenced mortality related to cardiovascular and lower-respiratory diseases in 15 U.S. states. The researchers found an increase in mortality related to cardiovascular and lower-respiratory-tract illness in counties infested with the emerald ash borer. The magnitude of this effect was greater as infestation progressed and in counties with above-average median household income. The authors suggested that the loss of trees to the emerald ash borer increased mortality related to cardiovascular and lower-respiratory-tract illness. The reliability of these conclusions however has been questioned (Frumkin, 2013).

3.3 Physical health and well-being

Lack of physical activity in daily life is known to have a range of negative health consequences. Recognition of the relationships between physical activity and health has occurred in response to the links between increasing mortality from non-communicable chronic diseases (such as coronary heart disease and diabetes) and sedentary lifestyles (Booth et al., 2001).The role of physical activity as a modifiable risk factor of disease has been well researched and is now firmly established (Kent et al., 2011). It is also evident that physical activity is linked to overall community well-being, through increased levels of social interaction and community engagement (Echeverría et al., 2008; Wood et al., 2010).

In addition, a range of other economic and environmental benefits due to physical activity have been identified (Bauman et al., 2008; Shoup and Ewing, 2010). In a study commissioned by the US Active Living Research foundation, (Shoup and Ewing, 2010) synthesized a number of research studies to identify the economic benefits of open space, recreation facilities and walkable community design. They found that open spaces have a positive effect on property values, which in turn can lead to higher tax revenues for governments. They also found that ‘people living in walkable neighbourhoods get about 35-45 more minutes of moderate-intensity physical activity per week, and are substantially less likely to be overweight or obese than do people of similar socio-economic status living in neighbourhoods that are not walkable.’ (Bauman et al., 2008) at the School of Public Health at the University of Sydney estimated that commuter cyclists currently save the Australian economy $72.1 million per year in reduced health costs.Other benefits quantified included reduced congestion ($63.9 million perannum) and reduced greenhouse gas emissions ($9.3 million per annum).

According to the (National Preventative Health Strategy, 2009), obesity-related disease will shortly be Australia’s primary preventable health problem. In 2008, obesity was estimated to have financial costs over $8 billion, and well-being benefits were valued at around $50 billion (Access Economics, 2008). In 2002, the direct health care costs of inactivity alone were estimated at $1.5 billion (Stevenson et al., 2000). A primary element of the strategy is to encourage activity for recreation and travel (where people choose to walk or ride rather than use a car) through better urban planning and design. A growing body of evidence suggests that green infrastructure such as trees and urban green spaces are critical elements of environmental design to ensure public health. The recent Inquiry into Environmental Design and Public Health in Victoria (Environment and Planning References Committee, 2012) found two particular elements of the built environment promote healthy lifestyles: provision of quality green and public open space, and environments that encourage active travel. Many studies suggest that aesthetically pleasing environments, and green spaces in particular, facilitate higher levels of recreational and transportational walking (Turrell 2010). This is reflected in government design guidance for environmental health where provision of trees for shade and amenity is encouraged to create walkable environments.An example is Healthy by Design SA prepared by the Heart Foundation SA and the South Australian Active Living Coalition (Heart Foundation, 2013).

Links to physical activity

There is a well-established link between participation in physical activity and the attributes of the physical environment (Booth et al., 2000). Considerable research supports the idea that the presence of green, natural settings can facilitate physical activity (Booth et al., 2000; Frank et al., 2004; Ellaway et al., 2005; McNeill et al., 2006; Mobley et al., 2006; Roemmich et al., 2006; Sugiyama and Ward-Thompson, 2007; Wendel-Vos et al., 2007; Black and Macinko, 2008; Sallis and Glanz, 2009; Galvez et al., 2010). Recent epidemiological studies provide evidence of the positive relationship between health, well-being and green places (de Vries et al., 2003). Other studies also emphasize the importance of walkable green spaces for older people (Takano et al., 2002).

It has been shown that the physical environment can be modified in a number of ways to influence physical activity (Kent et al., 2011). The scoping study by Abraham et al. (2010), referred to earlier, showed the way the urban landscape and environment is designed and built is crucial for the level of physical activity in daily life, work and leisure time (Frumkin et al., 2004; McCormack et al., 2004; Humpel et al., 2004a; Humpel et al., 2004b; Powell, 2005). For example:

  • It can be structured in ways that increase opportunities for, and reduce barriers to, physical activity.
  • It can influence travel behaviour, including the levels of walking, cycling, public transport and car travel, as well as the amount of leisure time that is available for other healthy pursuits.
  • It can increase opportunities for recreational activity, by providing useable open spaces, as well as streets conducive to walking and cycling.

Environmental attributes encouraging physical activity

A wide range of physical environment variables are known to promote and enable physical activity. These include:

  • Good access to destinations, the presence of physical activity-promoting facilities, and the general functionality of urban districts (e.g. presence of footpaths, effective traffic regulation) (Pikora et al., 2003; Pikora et al., 2006).
  • Design of bicycle and walking paths for better walkability and cycling (Frank and Engelke, 2001; Craig et al., 2002; Cervero and Duncan, 2003; Li et al., 2005).
  • Land-use-mix, street connectivity, traffic safety (such as pedestrian friendly zones), and aesthetically appealing landscapes (French et al., 2001; Saelens et al., 2003; Humpel et al., 2004a; Leslie et al., 2005; Titze et al., 2005).
  • In terms of physical activity specifically undertaken in leisure time, location and infrastructure, such as presence of a park, safety, and the absence of traffic, have been found to play an essential role (Booth et al., 2000; Neff et al., 2000; Ball et al., 2001).
  • Research has found that places for health-promoting physical activities should be made as user friendly as possible (Giles-Corti and Donovan, 2002; Wendel-Vos et al., 2007).
  • In northern Europe forests play an important role in terms of outdoor physical activity outside cities, especially where people use forests for recreation and exercise (Pretty et al., 2005b).
  • In order to be perceived as an option for physical activity, rural green landscapes need to be aesthetically appealing to their users (Pretty et al., 2005a).
  • (Addy et al., 2004) found that people gain additional motivation for regular physical activity when they trust their neighbours, when they perceive their neighbours as active, and when they have the opportunity to use nearby parks, playgrounds and sport fields.
  • It has been found that preferences, needs and ability to access places for physical activity vary according to gender, age and ethnic background (Eyler et al., 1998; Lee et al., 2001; Payne et al., 2002).

Research has focussed on the two main ways in which Green Infrastructure can be used to promote physical activity:

  1. Access to open or green space.
  2. Walkability of streets and other urban places.

These two topics are explored in the following sections.

3.3.3 Access to open space

According to (Kent et al., 2011):

‘People with access to good quality and safe open space are more likely to be physically active for recreation’ and ‘The location and treatment of green and open spaces facilitate contact with nature, as well as contact with community’.

Physical activity and open space

There is evidence of links between levels of physical activity and living in proximity to open space (Wendel-Vos et al., 2007; Sallis and Glanz, 2009). (Bauman and Bull, 2007) reviewed 13 studies which in turn reviewed ‘environmental correlates of physical activity and walking in adults and children’. The study found consistent associations between access, perceived safety and aesthetic features of parks and physical activity. Limitations identified in the review included a lack of standardization of measurement between studies, the wide variety of methods used and reliance on cross-sectional rather than longitudinal study design.

(Black and Macinko, 2008) cite a number of studies reporting that populations with better access to high quality open space are more likely to walk and undertake physical activity (Frank et al., 2004; Ellaway et al., 2005; Giles-Corti et al., 2005; Mobley et al., 2006).

Kaczynskl and Henderson (Kaczynskl and Henderson, 2008) reviewed 50 quantitative studies and identified a positive association between provision of recreational spaces and physical activity. (Bauman and Bull, 2007) concluded that living near parks, playgrounds, and recreation areas is consistently related to children’s total physical activity. This is supported by a number of other studies (Davison and Lawson, 2006; Dunton et al., 2010; Galvez et al., 2010; Loukaitou-Sideris, 2010).

Several studies show lower levels of obesity in greener neighbourhoods (Tilt et al., 2007; Bell et al., 2008). One study in Europe found that respondents living in greener neighbourhoods were 40% less likely to be overweight or obese (Ellaway et al., 2005). Similarly, two studies in the Netherlands and the United States found the showed an inverse relationship between body mass of children and exposure to green space, and that children were more likely to walk or cycle in greener environments (de Vries et al., 2007; Bell et al., 2008).

Proximity to green space has also been correlated with longevity of senior citizens in Tokyo, Japan (Takano et al., 2002). Another study in England found individuals below retirement age with greater exposure to green space had lower rates of mortality, including specifically from circulatory diseases (Mitchell & Popham 2008).

An Australian study found the presence of trees providing shade in open spaces was positively associated with an increased likelihood of being active (Timperio et al., 2008). While many further studies focus on green infrastructure in parkland settings, findings show streetscape greenery may be equally important (van Dillen et al., 2012).

Recent research published in the American Journal of Health Promotion explored the association between New York City residents' body mass index (BMI) and their access to neighbourhood parks, park quality, and park physical activity resources (Rundle et al., 2013). The results show that higher residential neighbourhood’s access to large parks (greater than 6 acres) was associated with lower BMI scores. The researchers concluded that neighbourhood proximity to large park spaces was modestly associated with lower BMI in a diverse urban population.

In a recent, study researchers used a simulation model to estimate the potential health benefits and cost-effectiveness of an urban regeneration project in Northern Ireland, the Connswater Community Greenway (Dallat et al., 2013). The researchers found that if 10% of those classified as ‘inactive’ (performing less than 150 minutes of moderate activity/week) became ‘active’, 886 incident cases (1.2%) and 75 deaths (0.9%) could be prevented with an incremental cost-effectiveness ratio of £4469/disability-adjusted life year. The researchers concluded that the greenway intervention could be cost-effective at improving physical activity levels. Although the direct health gains are predicted to be small for any individual, summed over an entire population, they are substantial. In addition, the Greenway is likely to have much wider benefits beyond health.

Design of open space

Research suggests that people have specific ideas about their ideal outdoor area for physical activity.

Giles-Corti suggests that the conventional concept of open space (such as sporting ovals) should be adapted to include open areas with shade and landscaping and which encourage walking as well as organised sport (Giles-Corti, 2006b). Other literature suggests that the aesthetic quality of recreational areas is also important (Galvez et al., 2010). According to (Kent et al., 2011):

‘Policies to maintain green and open spaces should embrace increased physical activity, social connectivity and improved mental wellbeing as desired outcomes. With continuing growth of urban populations, policies need to target the acquisition of land for greenspace and improve the quality of existing greenspace networks beyond their traditional role as recreational areas’.

Levels of open space provision

Despite the strength of this research, a recent study undertaken by (Searle, 2009) concludes that the provision of local open space in a number of high density developments in Sydney is well below best practice recommendations. Other studies have shown that many city dwellers in socially deprived areas lack access to places for physical activity (Popkin et al., 2005; Coen and Ross, 2006; Gordon-Larsen et al., 2006)

3.3.4 Walking and Cycling for Recreation

Recreational versus practical travel

Research suggests that the types of physical environment that encourage ‘practical’ walking and cycling (for example to work), are not necessarily the same as those that encourage walking and cycling for recreation purposes. Some of the factors relating to ‘practical walking’ include wider considerations of urban form, the design of pedestrian networks and the design of more ‘walkable’ neighbourhoods (ITE, 2010). (Southworth, 2005) reviewed a number of pedestrian plans and concluded that walkable neighbourhoods are associated with improved physical and mental health, and increased community vitality. Southworth identified the common characteristics of walkable neighbourhoods, which comprised:

  1. Connectivity
  2. Linkage with other modes
  3. Fine grained land use patterns
  4. Safety
  5. Quality of path (attention to details such as width, paving, landscaping and lighting)
  6. Path context (the path context is visually stimulating to the pedestrian)

(Saelens and Handy, 2008) analysed 42 reviews of built environment correlates of walking, differentiating between ‘transportation walking’ and ‘recreational walking’. The authors concluded that:

  • There are consistent associations between walking for transportation and residential density, distance to non-residential destinations, and land use mix.
  • Recent evidence found a less consistent relationship between transportation walking and pedestrian infrastructure, such as sidewalk presence and condition, although pedestrian infrastructure was more consistently related to recreation walking.
  • The evidence regarding children primarily relates to factors related to walking to school, and proximity, density, and the quality of the pedestrian infrastructure and traffic safety appear to play a role.

A study by (Owen et al., 2007) investigated relationships between neighbourhood walkability and the walking behaviour of adults in Adelaide, South Australia. The study surveyed 2650 adults from different neighbourhoods in the city having either high or low walkability based on an objective walkability index. The researchers found a strong association between weekly frequency of walking for transport and the neighbourhood walkability index. The study confirms associations of neighbourhood walkability with walking for transport in an Australian context.

Some of the key attributes that encourage ‘practical walking’ identified in the literature include:

  • Perceived and actual safety (Spangler-Murphy et al., 2005; Black and Macinko, 2008)
  • The provision of networks that are legible, well-maintained and well lit with footpaths, shade and landscaping (Powell et al., 2007; Saelens and Handy, 2008)
  • Aesthetics are also a key consideration(Agrawala et al., 2008)

With respect to ‘recreational walking’ the provision of special purpose walking trails has been shown to be likely to encourage walking. Australian studies demonstrate that people will use walking trails if they are provided (Merom et al., 2008). A review by (Kaczynskl and Henderson, 2008) on associations between parks and physical activity found that provision of open space was more positively correlated with walking for exercise than with recreation itself. According to (Lee and Moudon, 2004) evidence points to a latent demand for walking, suggesting an opportunity to increase walking through improved environments. Suggested improvements included increased land use intensity and mix along with investments in walking infrastructure, and greater focus by planners on enablers and constraints on walking.

The Green Infrastructure implications of the above research include enhancing physical activity through:

  • The provision of accessible open space
  • The provision of facilities for recreational walking, such as linear trails (see Figure 13)
  • Promoting transport walking by enhancing the walkability of streets and neighbourhoods with ‘greening’ improvements

Figure 13: Windsor Street linear trail, Adelaide. Source: M. Ely.

3.4 Psychological health and well-being

3.4.1 Overview

As discussed in Section 3.2, psychological as well as physical health is an important component of human health and well-being, as is a generally positive sense of mental well-being. (Abraham et al., 2010) identified the dimensions of mental well-being in the context of natural environments to include: attention restoration and recovery from mental fatigue; recovery from stress; and promotion of positive emotions. A large body of research emphasizes the social and psychological benefits of urban nature, urbangreening and urban trees (Tarran, 2006; Elmendorf, 2008; Tarran, 2009). Research has focused on three main areas:

  1. The deeper psychological attachment of people to nature.
  2. The benefits to human health and well-being of contact with nature.
  3. The role of urban greening in community building.

Much of this research has been carried out by social researchers, particularly in the US. Early research was undertaken by Rachel and Stephen Kaplan, who continue to conduct ongoing research at the University of Michigan School of Natural Resources and Environment (Kaplan et al., 1998). Later research was conducted by Frances Kuo and others at the University of Illinois Landscape and Human Health Laboratory (LHHL) (Kuo et al., 1998). Specific research into the human benefits of the urban forest has been carried out by urban forest researchers, including the work of the USDA Forest Service (Dwyer et al., 1991; Dwyer et al., 1992; Lewis, 1996).

3.4.2 Attachment to nature

In 1929, American biologist E.O.Wilson, known as the ‘father of socio-biology’ coined the term ‘biophilia’ to describe humans’ subconscious attachment to the rest of life, and suggested that this had its origins in human evolution (Wilson, 1984). Others consider this ‘biophilia hypothesis’ to be supported by evidence such as: human preferences towards nature (such as the popularity of landscape paintings); psychological well-being from exposure to nature; and even our history of gardening dating back to ancient times (Wilson, 1984; Kellert, 1997; Gullone, 2000). (Tarran, 2006) emphasizes the fundamental psychological benefits of urban trees. She considers that, while there may be technological alternatives which can provide the same environmental benefits as trees (for example shading):

‘…as regards social and psychological benefits, it may be that our attachment is so deep that urban nature is essential and not easily substituted' (Tarran, 2006) p.59.

(Ulrich, 1986) conducted a literature review of studies looking at the emotional and psychological responses to different natural environments, and found that humans have a strong preference towards nature, especially when trees are present.

3.4.3 The restorative effects of nature

A number of researchers have investigated the therapeutic and restorative effects of nature, including ‘attention restoration’ theory and ability to recover from mental fatigue.

3.4.3.1 Attention restoration theory

Rachel and Stephen Kaplan have investigated ways in which the natural environment can foster people’s wellbeing and their ability to function effectively (Kaplan and Kaplan, 1989; Kaplan, 1995a). Steven Kaplan’s ‘Attention Restoration Theory’ proposes that contact with nature engages our ‘involuntary attention’ giving our ‘directed attention’ (voluntary attention) the opportunity to rest, therefore helping to overcome the mental fatigue associated with continual directed attention (Kaplan, 1995a). The Kaplan’s have established four characteristics of such ‘restorative environments’ (Kaplan and Kaplan, 1989; Kaplan, 1995a; Kaplan, 1995b).

  1. First, restorative environments enable people to get some distance from their daily life
  2. Second, they attract people’s attention without being exhausting
  3. Third, they enable constant discovery of new things, mostly compatible with already existing information about the environment
  4. Fourth, they are in line with the intentions of their users, i.e. the environment enables the users to do what they want to do

(Herzog et al., 1997) consider that these environments contribute to attention restoration through clarifying and ordering thoughts and encouraging reflection on personal goals and vital matters.

3.4.3.2 Stress reduction theory

‘Stress reduction’ theory is a different proposition from ‘attention fatigue’. Stress reduction theory is closely related to the ‘biophilia hypothesis’ and is sometimes referred to as ‘psycho-evolutionary theory’. Stress reduction theory proposes that natural environments promote recovery from stress while urban built environments hinder the same process (Velarde et al., 2007; Konijnendijk, 2008). It is suggested that this is because the natural environment, in which humans evolved, does not require the processing of large amounts of information, therefore an individual’s level of arousal or stress is reduced by spending time in natural settings (Ulrich, 1979; Ulrich et al., 1991). Indicators for the positive effects due to nature have been measured, such as lower physiological excitation in terms of lower pulse rates and lower emotional arousal (Ulrich et al., 1991; Parsons et al., 1998; Laumann et al., 2003; Ulrich et al., 2003).

Ulrich examined the restorative effects of natural views on hospital patients, finding that those viewing natural scenes experienced a quicker recovery (Ulrich, 1981; Ulrich, 1984). A recent study by (Raanaas et al., 2012) also examined the health benefits of a bedroom window view to natural surroundings for patients undergoing a residential rehabilitation programme, using a longitudinal study methodology for studying 278 coronary and pulmonary patients. The subjects self-reported physical and mental health, subjective well-being, emotional states, use of the private bedroom and leisure activities. The research findings indicated that an unobstructed bedroom view to natural surroundings appears to have better supported improvement in self-reported physical and mental health during the residential rehabilitation programme, although the degree of change varied with gender and diagnostic group.

(Ulrich et al., 1991) also showed that when people look at a natural landscape, immediate, unconsciously released emotional reactions significantly affect their stress recovery. While looking at a landscape that is perceived as pleasant, negative feelings and thoughts, which had been previously induced by negative stress exposure, were replaced by positive feelings (Hartig et al., 1996). This reaction has been found to occur when the landscape contains particular visual stimuli such as a moderate complexity and richness of natural elements like waters or vegetation. (Hartig et al., 2003) pointed out that study participants taking a walk in the woods yielded lower emotional and physical stress levels when compared to those taking an urban walk. Contact with nature has also been shown to help drivers recover more quickly from stress and cope better with further stress (Parsons et al., 1998).

A study by (Berman et al., 2012) aimed to explore whether walking in nature may be beneficial for individuals with major depressive disorder (MDD). Healthy adults demonstrate significant cognitive gains after nature walks, but it was unclear whether those same benefits would be achieved in a depressed sample as walking alone in nature may induce rumination, thereby worsening memory and mood. Twenty individuals diagnosed with MDD participated in this study. At baseline, mood and short term memory span were assessed prior to taking a 50-minute walk in either a natural or urban setting. After the walk, mood and short-term memory span were reassessed. Participants exhibited significant increases in memory span after the nature walk relative to the urban walk, and also showed increases in mood, but the mood effects did not correlate with the memory effects, suggesting separable mechanisms. These findings extend earlier work demonstrating the cognitive and affective benefits of interacting with nature to individuals with MDD, indicate that interacting with nature may be useful clinically as a supplement to existing treatments.

New research at Edinburgh University supports the idea that spending time in green spaces reduces stress and brain fatigue (Aspinall et al., 2013). A body of literature on the restorative effects of nature focuses on the potential benefits to emotional recovery from stress offered by green space and 'soft fascination'. However, access to the cortical correlates of emotional states of a person actively engaged within an environment has not been possible until recently. What makes this study different from earlier research is that it looks at real-time data from the brains of people while they were actually outside, moving through the city and the parks. This study makes use of a recently developed lightweight, portable version of the electroencephalogram (EEG) as a method to record and analyse the emotional experience of a group of walkers in three types of urban environment including a green space setting. Using Emotiv EPOC (a low-cost mobile EEG recorder) participants took part in a 25 minute walk through three different areas of Edinburgh. The areas (of approximately equal length) were labelled zone 1 (urban shopping street), zone 2 (path through green space) and zone 3 (street in a busy commercial district). The equipment provided continuous recordings from five channels, labelled excitement (short-term), frustration, engagement, long-term excitement (or arousal) and meditation. A new form of high-dimensional correlated component logistic regression analysis showed evidence of lower frustration, engagement and arousal, and higher meditation when moving into the green space zone; and higher engagement when moving out of it. The researchers found systematic differences in EEG recordings between three urban areas in line with restoration theory. The researchers concluded that this has implications for promoting urban green space as a mood-enhancing environment for walking or for other forms of physical or reflective activity.

Green settings have also been found to have positive effects on young people with Attention Deficit Hyperactivity Disorder (ADHD) Faber Taylor and Kuo (2009); Faber Taylor and Kuo (2011) Faber Taylor, Kuo et al. (2001)

3.4.3.3 Studies on the restorative powers of nature

A number of research studies demonstrate the restorative powers of nature, including both the experience of views of nature, or actual interaction with nature itself. The following examples are drawn from a diverse range of studies.

View from a hospital window

One of the best known studies of the restorative powers of nature was by Roger Ulrich who showed that abdominal surgical patients had shorter post-operative hospital stays when in a room looking out on a stand of trees (Ulrich, 1984). Shortening hospital stays by 8.5% as reported would also have annual cost savings of several hundred million dollars (Ulrich, 1986).

Views of nature from a prison

(Moore, 1981) found a significant reduction in the use of health services by prisoners with exterior views to farmland from their cells.

View of nature from the workplace

Rachel and Steven Kaplan found that nearby nature, even viewed from a window, had substantial benefits in work settings including increased job satisfaction and well-being (Kaplan et al., 1988; Kaplan, 1993).

Recovery from mental fatigue

A number of studies have found that contact with nature in various forms aids recovery from mental fatigue and promotes enhanced cognitive functioning (Kuo and Sullivan, 2001b).

Residential settings

Several studies have examined the benefits of contact with nature in residential environments (Faber Taylor et al., 2002). Reported benefits include:

  • Increased residential satisfaction (Kaplan, 1985)
  • Enhanced well-being (Kaplan, 2001)
  • More effective patterns of coping (Kuo, 2001a)
  • Greater day-to-day effectiveness (Tennessen and Cimprich, 1995)

Children and greener housing

One study found that children moving from poor housing, to housing with improved ‘greenness’, experienced improved cognitive functioning  (in terms of attentional capacity) (Wells, 2000).

Access to nearby nature

Research has found that parks provide refuges for privacy, away from the home and the work environment, and that people visiting these areas for privacy nominated ‘reflective thought’ as the most important reason for visiting (Hammitt, 2002).

Restorative effects of natural landscapes

A number of studies emphasize the fact that natural landscapes are more restorative than urban ones. (Hartig et al., 2003) showed that walks in natural landscapes have a stronger positive effect on the ability to concentrate than urban walks. This is supported by other studies that suggest people prefer natural landscape (such as beaches, waters, forests, parks, and mountains) for recovery from mental fatigue (Korpela and Hartig, 1996; Korpela et al., 2001; Staats et al., 2003; Staats and Hartig, 2004). A study by (Herzog et al., 1997) in which participants rated the perceived restorative effectiveness of three kinds of settings (ordinary natural, sports/entertainment, and everyday urban) suggests that natural settings have a high restorative potential, public open spaces used for public entertainment and sports have an intermediate restorative potential, and urban settings have a low restorative potential. The restorative potential of natural landscapes was also demonstrated in an experimental study by (Berto, 2005) in which exposure to pictures of natural landscapes had a restorative effect on mental fatigue in students. Such results are in line with findings of two earlier studies, which measured the effect of a view of a landscape on concentration (Tennessen and Cimprich, 1995; Kuo, 2001a).

The scoping study by Abraham et al. (2010) also identified the importance of low sound levels for rest and relaxation: people who have easy access to green areas can reduce noise annoyances and thus become more relaxed (Gidlof-Gunnarsson and Ohrstrom, 2007). A number of other studies have found that trees and other greenery in urban areas reduce stress and improve physical and psychological health (de Vries et al., 2003).

3.4.3.4 The research of Kuo, Sullivan and others

At the University of Landscape and Human Health Laboratory, Kuo, Sullivan and others are currently researching inner-city residents’ responses to trees and other vegetation and the ways in which the physical and psychological health of individuals and communities can be improved with enhanced access to nearby nature and natural views (http://lhhl.illinois.edu/research.htm). (Kuo, 2001a) suggests that nature may be an essential component of the human habitat, as evidenced by the apparent effects of nature on health and well-being criteria such as blood pressure, heart rate, mood, day-to-day effectiveness, social behaviour, cognitive functioning and work performance. According to Kuo(2001a p29), ‘Regular contact with nature may be as important to our psychological and social health as the regular consumption of fruit and vegetables is to our physical health’p.29. She recommends that:

  • People should spend time in green, natural settings to relax and recover the ability to concentrate on challenging tasks.
  • Trees should be planted and maintained near homes, schools, work sites and other places where concentration and mental energy were needed most.
  • Indoors, time should be spent in places where there is a green view to nature from a window, and desks at work and school should be arranged to provide a green view.
  • More green spaces should be created, especially in inner city neighbourhoods.

Research at the Landscape and Human Health Laboratory is summarised below under the following six themes.

Green Play Settings Reduce ADHD Symptoms

The Landscape and Human Health Lab’s research has shown that performing activities in green settings can reduce children’s Attention Deficit-Hyperactivity Disorder symptoms. In an initial survey, parents of children with ADHD were more likely to nominate activities that typically occur in green outdoor settings as being best for their child’s symptoms, and activities that typically occur in indoor or non-green outdoor settings as worst for symptoms. Also, parents rated their child’s symptoms as better, on average, after activities that occur in green settings than after activities in non-green settings (Faber Taylor et al., 2001).

In the subsequent, nation-wide survey, parents again rated leisure activities, such as reading or playing sports, as improving children’s symptoms more when performed in green outdoor settings than in non-green settings (Kuo and Faber Taylor, 2004). A more recent study tested children with ADHD in a controlled setting after they had walked in one of three environments that differed from one another in the level of greenery: a park, a neighbourhood, and a quiet downtown area. The findings confirmed that the attention of children with ADHD functions better after spending time in more natural settings (Faber Taylor and Kuo, 2009). The authors concluded that the research findings suggest adding trees and greenery where children spend a lot of time, such as near homes and schools, and encouraging children with ADHD to play in greenspaces may help supplement established treatments to improve their functioning.

Views of Greenery Help Girls Succeed

In a study conducted in a Chicago public housing development, girls who lived in apartments with greener, more natural views scored better on tests of self-discipline than those living in more barren but otherwise identical housing. The study tested children on three component abilities of self-discipline: concentration, inhibition of impulsive behaviour, and delay of gratification. Girls with green views scored higher on average than girls with less green views on all three tests. Boys showed no link between test scores and the amount of nature near home. The researchers suggested that this may be because they spend less time playing near home and are then less affected by the environment around it (Faber Taylor et al., 2002).

Adding Trees Makes Life More Manageable

In a study conducted in a Chicago public housing development, women who lived in apartment buildings with trees and greenery immediately outside reported greater effectiveness and less procrastination in dealing with their major life issues than those living in barren but otherwise identical buildings. In addition, the women in greener surroundings found their problems to be less difficult and of shorter duration. The authors concluded that trees may help poor inner city residents cope better with the demands of living in poverty, feel more hopeful about the future, and manage their most important problems more effectively (Kuo, 2001a).

Vegetation May Cut Crime in the Inner City

In a 2001 study in a Chicago public housing development, dramatically fewer occurrences of crime were observed against both people and property in apartment buildings surrounded by trees and greenery than in nearby identical apartments that were surrounded by barren land (Kuo and Sullivan, 2001b). Compared with buildings that had little or no vegetation, buildings with high levels of greenery had 48 percent fewer property crimes and 56 percent fewer violent crimes, and even modest amounts of greenery were associated with lower crime rates. Kuo suggests that greenery can lower crime through several mechanisms. First, greenery helps people to relax and renew, reducing aggression. Second, green spaces bring people together outdoors, increasing surveillance and discouraging criminals. Relatedly, the green and groomed appearance of an apartment building is a cue to criminals that owners and residents care about a property and watch over it and each other.

Trees Linked with Less Domestic Violence in the Inner City

In a study conducted in a Chicago public housing development, women who lived in apartment buildings with trees and greenery immediately outside reported committing fewer aggressive and violent acts against their partners in the preceding year than those living in barren but otherwise identical buildings. In addition, the women in greener surroundings reported using a smaller range of aggressive tactics during their lifetime against their partner (Kuo and Sullivan, 2001a).

Where Trees are Planted, Communities Grow

It appears that residential common areas with trees and other greenery help build strong neighbourhoods. In a study conducted at a Chicago public housing development, residents of buildings with more trees and grass reported that they knew their neighbours better, socialized with them more often, had stronger feelings of community, and felt safer and better adjusted than did residents of more barren, but otherwise identical, buildings (Kuo et al., 1998).

Kuo explains this link between landscaping and stronger ties between residents and their neighbourhood. When the spaces next to residences are green, they are both more attractive and more comfortable, drawing people to them. Such settings support frequent, friendly interaction among neighbours, the foundation of neighbourhood social ties. These ties are the heart of a neighbourhood’s strength, encouraging neighbours to help and protect each other. Sharing resources with and depending upon neighbours may be especially crucial to impoverished inner-city families, so it is especially important to plant and maintain trees in such neighbourhoods.

The Landscape and Human Health Lab also currently has a new project in progress. The Capacity to Learn study will examine the effects of schoolyard nature on children’s learning and academic achievement as reflected in standardized test scores. The study aims to document whether children learn more in green school settings.

3.4.3.5 Crime reduction

There is longstanding belief that vegetation encourages crime as it can conceal criminal activity. Recent studies, however, have suggested the opposite (Troy et al., 2012) and have shown that urban residential areas with well-maintained vegetation experience lower rates of certain crime types due to increased surveillance in vegetated spaces as well as the therapeutic effects ascribed to vegetated landscapes. (Kuo and Sullivan, 2001b) argue that the presence of vegetation, particularly in public spaces, can deter crime by encouraging greater use of public space, thereby providing greater social supervision which acts to suppress criminal activity. In addition, (Kaplan, 1987) suggests that vegetation may have a mentally restorative effect that reduces the psychological precursors to criminal acts, particularly for violent crimes.

A recent research project (Wolfe and Mennis, 2012) analysed the association of vegetation with crime in a case study of Philadelphia, Pennsylvania. The researchers examined rates of assaults, robberies, burglaries, and thefts in relation to remotely sensed vegetation abundance. The results indicated that vegetation abundance was significantly associated with lower rates of assault, robbery, and burglary, but not theft. This research has implications for urban planning policy, especially as cities are moving towards ‘green’ growth plans which must look to incorporate sustainable methods of crime prevention into city planning.

Troy et al (Troy et al., 2012) examined the extent to which urban tree cover influences crime, a subject of debate in the literature. This research took advantage of geocoded crime point data and high resolution tree canopy data in Baltimore City and County, MD, an area that includes a significant urban–rural gradient. The researchers found that there is a strong inverse relationship between tree canopy and their index of robbery, burglary, theft and shooting. The more conservative spatially adjusted model indicated that a 10% increase in tree canopy was associated with a roughly 12% decrease in crime. The relationship continued for both public and private ownership, but the magnitude was 40% greater for public than for private lands. These results do not establish causality, but suggest a strong need for further research to determine the role of vegetation in mediating crime.

3.4.3.6 Proximity to green space

Findings from previous research suggested a correlation between green space and well-being, but those studies were not able to rule out the possibility that people with higher levels of well-being simply move to greener areas. Recent research by (White et al., 2013) at the European Centre for Environment & Human Health at the University of Exeter Medical School, attempted to advance the field by using by using ‘panel’ data from a national longitudinal survey of households in the United Kingdom, which collected data annually from over 10,000 people between 1991 and 2008. The data was used to explore the relationship between urban green space and well-being (indexed by ratings of life satisfaction) and between urban green space and mental distress (indexed by General Health Questionnaire scores) for the same people over time. Controlling for individual and regional variation the researchers found that, on average, individuals have both lower mental distress and higher well-being when living in urban areas with more green space. According to the researchers (p.920): ‘Living in an urban area with relatively high levels of green space compared to one with relatively low levels of green space was associated with a positive impact on well-being equivalent to roughly a third of the impact of being married vs. unmarried and a tenth of the impact of being employed vs. unemployed’.

Researchers found that individuals reported less mental distress and higher life satisfaction when they were living in greener areas. And this association held even after the researchers accounted for changes in participants’ income, employment, marital status, physical health, and housing. Key findings included:

  • As green space increased within a 2.5-mile radius of where they lived, overall well-being increased proportionally. Specifically, life satisfaction increased by 2% and psychological distress decreased by 4%.
  • In relative terms, living in a greener area was associated with mental health gains about 35% as significant as those one gets from being married. It was 12% as beneficial to mental health as employed.
  • In terms of ‘life satisfaction’, the effect was equal to 28% that of being married and 21% that of being employed.

The research does not prove that moving to a greener area will necessarily cause increased happiness, but it does fit with findings from experimental studies showing that short periods of time spent in a green space can improve people’s mood and cognitive functioning. Although effects at the individual level were small, the potential cumulative benefit at the community level highlighted the importance of policies to protect and promote urban green spaces for well-being.

3.4.3.7 Evoking positive emotions

Studies suggest that views of a natural landscape enable people to express positive feelings such as joy and satisfaction more easily (Hartig et al., 1999). (Kaplan, 2001; Korpela et al., 2002). Open and accessible forests are suggested to enhance positive emotions more than dense and less accessible forests (Staats et al., 1997; Milligan and Bingley, 2007). With respect to the general positive impacts on mood, Cackowski and Nasar showed that a pleasant landscape contributes to higher frustration tolerance (Cackowski and Nasar, 2003).

3.4.3.8 Ability to escape

The ability to ‘escape’ the urban environment to experience nature is also an important consideration.

(Guite et al., 2006)measured the impact of physical and social factors in the built environment on the mental health of 2,696 adults in higher density areas in London. The researchers found that the perceived ability to escape to green spaces away from noise and over-crowding was significantly linked to mental well-being. In Sweden (Gidlöf-Gunnarsson and Öhrström, 2007) used questionnaires to assess the role of nature in providing escape, rest and relaxation for a sample of people living in high density developments that were either noise-affected or noise-unaffected. It was concluded that easy access to nearby green areas can offer relief from long term noise annoyances and reduce the prevalence of stress related psychological symptoms.

3.4.3.9 Future discounting

A recent study investigated the relationship to exposure to nature, and the human tendency to ‘discount the future’, which acts as an important barrier to enduring behavioural change (van der Wal et al. 2013).  The study drew on evolutionary theories of life history and biophilia.  The  results of three studies, two laboratory experiments and a field study reveal that individual discount rates are systematically lower after people have been exposed to scenes of natural environments as opposed to urban environments. The finding that nature exposure reduces future discounting was considered to have important implications for a range of personal and collective outcomes including healthy lifestyles, sustainable resource use and population growth.

 

3.4.3.10 Social interaction

As discussed earlier, research by Kuo and others has shown that the presence of nature, including housing areas with trees and greenery, can enhance the physical and social health of individuals and communities, including reducing aggression and crime. It can increase feelings of safety, as well as reducing vandalism and littering (Coley et al., 1997Kuo et al., 1998a;Herzog and Chernick, 2000Kuo and Sullivan, 2001aKuo and Sullivan, 2001bKuo, 2003).The presence of vegetation, such as greenery and trees, has also been found to increase social interaction in urban neighbourhoods (Kuo et al., 1998). This does not necessarily imply a direct cause and effect between urban nature and human behaviour, but rather a consequence of enhanced social interaction opportunities in urban green spaces (Elmendorf, 2008).Trees and greenery increase the attractiveness of places for people, in turn promoting community socialization and passive surveillance, which can reduce crime and increase personal safety (Coley et al., 1997;Kuo and Sullivan, 2001bKuo, 2003).

3.4.4 Community and identity

3.4.4.1 Sense of community and physical/mental health

The relationships between human health and well-being, and social interaction and sense of belonging to a community, have been well researched and are now widely accepted (Kent et al., 2011). It has been shown that people develop a sense of community when they feel part of a group (Butterworth, 2000). This sense of community includes feelings of social connection and belonging, which have been identified as influential determinants of mental and physical health (Baum and Ziersch, 2003; Ogunseitan, 2005; Baum et al., 2006; Poortinga et al., 2007; Cohen et al., 2008; Echeverría et al., 2008).

3.4.4.2 Social interaction and the physical environment

The built environment, including the presence of Green Infrastructure, can foster a sense of community through enabling day to day interactions with other people, and with nature. According to a number of authors, urban parks and other public places can enhance social integration if they facilitate factors such as: social contacts, exchange, collective work, community building, empowerment, social networks and mutual trust (Armstrong, 2000; Leyden, 2003).

Being ‘out and about’

As well as being socially connected to others, a sense of belonging has been found to foster perceptions of security, confidence and comfort which can encourage people to be ‘out and about’, and physically active in their neighbourhood, (Baum et al., 2006; McNeill et al., 2006; Michael et al., 2006; Wood et al., 2010; Kent et al., 2011). Being ‘out and about’ also increases opportunities for incidental social interactions. Incidental interaction has been shown to have a number of benefits including: augmented connection and caring, increased perceptions of safety and decreased feelings of loneliness and isolation, all of which have well-established links with mental health (Maas et al., 2009a; Maas et al., 2009b; Berry and Welsh, 2010; Yang and Matthews, 2010).

In the Netherlands, (Maas et al., 2009a) explored the hypothesis that green space improves health primarily through fostering of increased social contact. The researchers found an inverse relationship between green space in people’s living environment and feelings of loneliness, with less green space being associated with a perceived shortage of social support. (Cohen et al., 2008) analysed data from the Los Angeles Family and Neighbourhood Study (LAFANS) to identify the social and environmental features, including the presence of parks, which were associated with personal reports of ‘collective efficacy’. The study found that parks were positively associated with ‘collective efficacy.’ The authors concluded that parks set the scene for neighbourhood social interactions, creating a foundation underlying positive health and well-being.

3.4.4.3 Specific demographic groups

The aged and migrants

The socially integrative functions of landscape have been found in studies of elderly people (Kweon et al., 1998; Booth, Owen et al., 2000; Milligan et al., 2004) and of migrant groups (Rishbeth and Finney, 2006). Research by Inclusive Design for Getting Outdoors (IDGO, 2012) has found that the design of Britain’s gardens, streets, neighbourhoods and open spaces affects older people’s ability to age well and live independently by supporting, or preventing, access for all. People who do not find it easy or enjoyable to ‘get outdoors’ can spiral into poor physical health, reduced social contact with others and a lower quality of life overall. If older people live in an environment that makes it easy and enjoyable to go outdoors, they are more likely to be physically active and satisfied with life and twice as likely to achieve the recommended levels of healthy walking. The authors conclude that: ‘If an older person cannot get out and about locally, they are at risk of becoming ‘a prisoner in their own home’.

According to Catherine Ward Thompson (2011) in the UK, for older people, access to attractive outdoor places in the local neighbourhood is associated with multiple benefits (Sugiyama and Ward-Thompson, 2007) including more walking (Li et al., 2005; Sugiyama et al., 2008) which is known to enhance health and functioning (Weuve et al., 2004; Simons and Andel, 2006) and longevity (Takano et al., 2002). At the same time, a combination of decreasing functional capability and barriers in the environment may act as deterrents to outdoor activity for older adults (Lawton, 1986). (Sugiyama and Ward-Thompson, 2007) found that parks were integral to interaction in an elderly cohort of UK residents. The authors reviewed recent literature in gerontology, public health, environmental psychology, landscape architecture, and urban design, and found that the supportiveness of neighbourhood environments that make outdoor activity such as walking easy and enjoyable, is conducive to a better quality of life for older people. The aesthetic qualities of open space, ease and safety of access, and the opportunities it offers for social interaction, were found to be important predictors of both quality of life and levels of physical activity (especially walking) for older people.

With respect to migrants, Rishbeth and Finney(2006) investigated migrants’ perceptions and experiences of 10 urban green-spaces in Sheffield in the UK. The research used innovative participatory and visual (photography) methods. The participants were all asylum seekers and refugees from Asia and Africa. The research examined how and why participants engaged or disengaged with local green-space. The authors concluded that a positive impression of the local environment, and meaningful participation in it, can assist with integration into a new society. Furthermore, recognition of familiar landscape elements can provide a conceptual link between former and new homes. However, for this specific refugee group many physical and psychological barriers needed to be overcome for the full benefits of urban public open space to be realised.

Children

In Melbourne (Maller et al., 2010) interviewed informants in 12 primary schools to identify ways to enhance the frequency of chance encounters with nature by children. Learning activities such as tending gardens with vegetables, flowers, and native plants, and practising habitat conservation as well as caring for animals, were all observed by interviewees as benefiting children’s health and well-being, particularly their mental health. According to the authors ‘In the high-rise developments studied, residents were found to prefer natural scenery such as trees, parks, or bodies of water, rather than images of the built form, noting that the views of nature evoked feelings of relaxation and resulted in self-perceptions of higher well-being’ p.555. (Wake, 2007) described ways to encourage the involvement of children in natural spaces, including gardens. Johnson, (2007) also examined the importance of facilitating children’s incidental interaction with nature through environmental learning activities.

3.4.4.4 Desirable attributes of social public space

The literature suggests that urban landscapes should provide a sufficient level of safety, attractiveness and walkability, and should serve multiple purposes (Baum and Palmer, 2002; Leyden, 2003). They should also be rich in vegetation to promote social integration (Coley et al., 1997; Kuo et al., 1998a; Sullivan et al., 2004).

3.4.4.5 Community gardening

An important role of community gardens is that of promoting social interaction for a range of demographic groups.According to (Kent et al., 2011)‘Community gardens are forums for incidental and organised interaction. They are spaces for people to establish and maintain contact with community and contact with nature’ p.81. The health-promoting impact of community gardening was addressed in recent article. Among other benefits, community gardening was found to foster the development of community networks and social support and to motivate people towards community engagement (Wakefield et al., 2007). This research complemented findings from earlier studies regarding the health benefits of community and private gardens (Irvine et al., 1999; Armstrong, 2000; Brown and Jameton, 2000; Hancock, 2000; Doyle and Krasny, 2003; Twiss et al., 2003; Waliczek et al., 2005). In a comprehensive study of the community garden movement in the UK, Holland (2004) using both quantitative and qualitative methods, concluded that while some gardens played a strategic role in food production, all gardens were ‘based in a sense of community, with participation and involvement being particularly strong features’ p.1.

(Bartolomei et al., 2003) examined the social and health-promoting roles of a community garden scheme in a high-rise public housing estate in Sydney. The findings confirmed the role of community gardens in strengthening social interaction. The scheme was associated with increased opportunities for local residents to socialise and develop vital cross-cultural ties in a very diverse environment. The authors noted that: ‘there were many stories of how participating in the Gardens has helped to diminish cultural boundaries and negative racial stereotypes’ p.5. (Thompson et al., 2007) also note that ‘Community gardens can play a significant role in enhancing the physical, emotional and spiritual well-being necessary to build healthy and socially sustainable communities’  p. 1034.(Kingsley et al., 2009) studied community gardens in Melbourne. The authors described community gardens as places of refuge and social support, where knowledge is shared. These conclusions are generally supported by other studies indicating that the benefits of community gardens extend well beyond physical activity and access to healthy food (Hynes and Howe, 2004; Thompson et al., 2007; Wakefield et al., 2007; Macias, 2008; Teig et al., 2009).

3.5 Benefits to children

3.5.1 Overview

The benefits of nature to children, and the role of nature in childhood development, have become  significant research topics in recent years, due to links between the dramatic increase in childhood physical and mental health problems, and the decline in children’s interaction with natural environments.

Figure14 summarizes the ways in which children’s health and well-being can be influenced by contact with nature.

Figure 14: Summary of benefits to children of interaction with nature. Source: M. Ely.

Nature, in the form of Green Infrastructure, has been found to contribute to a child’s physical health, mental health and general cognitive functioning.

  • Physical health. Playing in natural settings can help reduce childhood obesity, and improve motor coordination.
  • Mental health. Playing in, or exposure to natural settings can improve children’s mental health in a number of ways, including relieving stress, combating depression through building self-esteem, and dealing with the symptoms of ADHD.
  • Cognitive function. It has also been shown that interaction with nature can improve a child’s overall cognitive functioning. This includes the fostering of creativity and imagination, and of the cognitive abilities required in the school classroom, such as general cognitive skills, ability to concentrate through ‘attention restoration’, and the gaining of direct knowledge of the natural world. Lastly engagement with nature while young appears to assist in the development of responsible attitudes to the environment in later adult life.

A study commissioned by Planet Ark in 2012, Planet Ark Planting Trees,  investigated the ‘intellectual, psychological, physical and mental health benefits of contact with nature for children’ (Planet Ark, 2012). A review of local and international research in this field revealed an emerging body of evidence that ‘contact with nature during childhood could have a significant role to play in both the prevention and management of certain physical and mental health problems, and in forming environmentally responsible attitudes in future adulthood’  p.2. The study also included attitudinal research into how Australians perceive the link between nature and children’s health, wellbeing and development.

3.5.2 Children’s health issues

Children’s health trends

Despite Australia’s high standard of living and outdoor climate, emerging physical and mental health epidemics have been observed among Australian children in the last few decades. Nearly a quarter of Australian children have been found to be overweight or obese (Australian Government Department of Health and Ageing, 2008). Obesity itself is linked to other health problems and also increases the likelihood of health issues in later adulthood, including type 2 diabetes. Public health authorities have warned that Australia is facing a ‘chronic disease time bomb’ (Malkin, 2011). There are also growing concerns for childhood mental health, and it has been shown that 14% of Australian children have been diagnosed with a mental health disorder. Attention deficit hyperactivity disorder (ADHD) is characterised by inattentiveness, impulsiveness, and hyperactivity. While it is accepted by the medical profession that ADHD does exist, there is still disagreement about the number of people affected. In Australia, the Child and Adolescent Component of the National Survey of Mental Health and Well-being reported ADHD to be present in 11% of children and adolescents, primarily in boys (Sawyer et al., 2000). According to the Australian Guidelines on Attention Deficit Hyperactivity Disorder (ADHD) (Royal Australasian College of Physicians, 2009) 5%-10% of the Australian population is diagnosed with ADHD.

Children’s lifestyle changes

The rise in childhood obesity and mental health issues in the last 20 years has been linked to dramatic lifestyle changes. Researchers by (Planet Ark, 2012) has documented these changes including:

  • Indoor rather than outdoor play. Children now spend significantly more time inside, rather than outside playing and interacting with nature, than in the 1980s (Hofferth and Curtin, 2003; Clements, 2004; Louv, 2005).
  • Structured rather than self-directed play. Children today engage in different outdoor activities compared with the previous generation. This includes increased time spent in activities which are structured or arranged by adults, and increased time in adult-supervised sport. This coincides with a significant decrease in the time spent by children in self-directed activities such as climbing trees or exploring natural settings (Clements, 2004).
  • Changes to housing. The traditional house and garden on a quarter acre block is now being replaced with a trend towards larger houses on smaller blocks, usually with little garden space, with low maintenance gardens or no gardens at all being favoured by ‘time-poor’ parents. The emphasis on leisure activities has also shifted from outdoor to indoors and new homes are often equipped with large indoor spaces for the latest technology such as ‘home theatres’ and computer games (Hamilton and Denniss, 2005; Hall, 2008; Hall, 2010).
  • Urban densification. Cities are becoming denser due to urban infill of existing suburbs, and denser new housing developments, often promoted for reasons of the supposed increased sustainability of more compact urban developments. However this comes at the expense of private and public green spaces, that once provided the settings for nature based play (Kinner and Wilson, 2011).
  • Fear. Society has seen a heightened fear of ‘stranger danger’, either real or perceived, which has decreased parents’ willingness to allow their children to engage in unsupervised outdoor play. At the same time, changing work patterns have reduced the time that many parents can spend with their children in outdoor activities (Clements, 2004).
  • Electronic media. Children are now spending more time using the various forms of electronic media (Australian Government Department of Health and Ageing, 2008). Research suggests that video games can be particularly addictive (Phillips et al., 1995). In addition, television and electronic games have become attractive ‘baby sitters’ that require little adult supervision.
  • Gadgets. Research has shown that time spent playing with gadgets can come at the expense of time spent interacting with other family members and participating in creative or outdoor play (Koger and Winter, 2010). Researchers have linked this ‘nature and culture deprivation’ with electronic media use (Brook, 2010).
  • Materialism. Researchers have suggested that increased television watching and sedentary lifestyles can increase ‘materialism and consumerism’among children which in turn has a negative influence on their physical health, for example by consuming ‘junk food’ (Koger and Winter, 2010).

Research by Planet Ark

The 2012 study by Planet Ark, which explored people’s perceptions of the link between nature and children’s health, wellbeing and development, included a survey of 1006 Australians aged 18-85 (Planet Ark, 2012). In the survey respondents reported on the activities undertaken by the children under their care. Playing in the backyard or an urban park was the most recent and common outdoor, nature-based activity reported by carers. Other findings reflect the changes in lifestyles identified above, including:

  • 25% of carers said the children in their care have never climbed a tree
  • 26% of carers said the children in their care have never been bushwalking
  • 17% of carers said the children in their care have never visited a national park
  • 11% of carers said the children in their care have never been to the zoo
  • 39% of carers said the children in their care have never been camping

Figure 15: Children's most recent outdoor nature based activity as reported by their carers. Source: Planet Ark (2012).

A 2004 study in the US, An Investigation of the Status of Outdoor Play, looked at the extent to which children in the US ‘today’ participate in active, outdoor play, compared with the previous generation (Clements, 2004). The study surveyed 830 mothers across the US with children between the ages of 3 and 12, and compared the mothers’ active outdoor play experiences as a child, with their children’s current reported play experiences. The study found that children ‘today’ spend considerably less time playing outdoors than their mothers did as children. The study identified several fundamental reasons for this decline, including dependence on television and digital media, and concerns about crime and safety.

In 2011, Planet Ark commissioned an independent study, Climbing Trees: Getting Aussie Kids Back Outdoors, to investigate children’s interaction with nature, and how this interaction may be changing between generations (Planet Ark, 2011). The study was based on an online survey of a representative sample of 1,002 Australians aged 14-65 years, who reported on their children’s play behaviour, and their own play behaviour as a child. The research produced similar results to the earlier 2004 US research, and the key findings are discussed below.

The Decline in Outdoor Play in Australia

‘Australia is a nation defined by its outdoor environments – the red centre, golden beaches, the bush and clear blue seas. However, our research reveals that one in ten Aussie kids plays outside once a week or less. We have become a nation of indoors, not outdoors’.

‘The landscape of childhood has changed. In a single generation, we have seen a profound shift from outdoor to indoor play, with 73% of respondents indicating that as children they played outdoors more often than indoors compared to only 13% of their kids. Additionally, 72% of survey respondents indicated that they played outside every day when they were young compared to only 35% of their children’.

Source: Planet Ark (2011) p.5.

The research shows that there has been ‘a dramatic shift in childhood play activity in the space of just one generation’ from outdoor play to indoor activities. For example:

  • 73% of respondents played outdoors more often than indoors when they were young compared with only 13% of their children
  • 72% of respondents played outside every day as children compared with only 35% of their children
  • One in 10 children today plays outside once a week or less

Figure 16: Kids' level of outdoor vs. indoor activity now compared with previous generation. Source: Planet Ark (2011).

The Nature of Outdoor Play

‘Kids don’t climb trees anymore, with less than 20% of respondents indicating their kids participate in this iconic outdoor activity. This is a staggering drop from the 65% of parents who were climbing trees during their childhood’.

Source: Planet Ark (2011) p.5.

As well as playing outdoors less often, the nature of children’s outdoor activity also appears to have changed. for example:

  • 73% of respondents said they played on the street when they were young compared with only 24% of their children
  • 64% of respondents said they climbed trees when young compared with only 19% of their children

Figure 17: Outdoor activities participated in by children now compared with previous generation. Source: Planet Ark (2011).

Benefits of Outdoor Play

Even with these dramatic changes in children’s play, respondents still believed in the benefits of active outdoor play.

  • 92% of respondents agreed that outdoor play allows children to use their imagination
  • 93% of respondents agreed that outdoor play helps develop physical and motor skills
  • 90% of respondents agreed that outdoor play provides an outlet for reducing everyday stress

Barriers to Outdoor Play

The research has shown that the ‘collapse in outdoor play’ can be attributed to a number of barriers, either real or perceived.

  • Crime and safety concerns showed the most dramatic increase, and 33% of respondents indicated that this is a barrier today compared with 9% who stated that it was a barrier when they were young.
  • Lack of time parents have to play outside with their children has also become a more significant barrier, with 26% of respondents stating that this is a barrier today, compared with 11% saying it was a barrier when they were young.
  • The amount of homework children have to do does not appear to be a barrier to outdoor play however, with the reported time spent on homework remaining fairly consistent across the generations.

Conclusions

The Planet Ark researchers concluded that children respond to their parents’ fears, which influences the activities that children choose to participate in (Tranter and Malone, 2004).While parents understandably prioritise safety issues, many seem to be unaware of the developmental risks of restricting outdoor activities. Not allowing children to play freely and explore their outdoor environment results in the single benefit of safety, however this benefit can be outweighed by multiple risks such as: compromised development; decreased physical exercise; increased obesity; and limited spontaneous play opportunities (Little and Wyver, 1998). An alternative view to removing all risk is that minor injuries, like grazes, are a universal part of growing up. Taking moderate risks is essential to healthy development even though it may sometimes result in minor injuries (Bundy et al., 2009).

‘Children respond to their parents’ fears and thus the attitudes of parents and caregivers will help to determine the activities that children choose to participate in, including outdoor play. While parents understandably prioritise safety issues associated with outdoor play, what parents seem to be unaware of is that restricting outdoor activities also involves social and cognitive development risks. There are a wide range of benefits - physical, cognitive and general wellbeing – that come from outdoor play’.

 Source: Planet Ark (2011) p.5.

3.5.4 Nature-Deficit Disorder

Writer Richard Louv in his book Last child in the Woods coined the term Nature-Deficit Disorder (NDD) to describe the effects on children of enforced alienation from nature. Alienation from nature leads to a number of behavioural issues, including diminished use of the senses, attention difficulties and higher rates of physical and emotional illness. Louv argues that sensationalist media coverage and paranoid parents have literally ‘scared children straight out of the woods and fields’ while promoting a litigious culture of fear that favours ‘safe’ regimented sports over imaginative play. While not an actual medical diagnosis NDD provides a useful way of thinking about a current problem and of possible means of dealing with it (Louv, 2005; Louv, 2011). By giving the phenomenon a name that evokes the language of mental health, Louv highlights NDDS as something ‘that is not normal or healthy, but rather a serious problem that society needs to recognise and address’ (Planet Ark, 2012).

Other researchers have described this trend as ‘nature and culture deprivation’ (Brook, 2010). A number of organisations are working to combat the nature deprivation phenomenon, including:

  • Children & Nature Network (co-founded by Louv)
  • No Child Left Inside Coalition

In Australia:

  • Planet Ark’s National Tree Day
  • Junior Landcare
  • Nature Play WA, SA & Qld
  • Victorian Child & Nature Connection

In an article entitled ‘Rediscovering Nature in Everyday Settings: Or How to Create Healthy Environments and Healthy People’ Maller et al. (2009) suggests there is a need to get nature back into our cities and towns to create healthier environments for people and to foster the connection between humans and nature. This can occur in ‘everyday urban places’ such as schools, work places and residential housing. (Maller et al., 2009). The US based Children & Nature Network (C&NN) has reviewed and summarized literature related to outdoor and nature contact and children’s health and well-being (Children & Nature Network, 2010).

Nature Deficit Disorder

‘A recent study from Australia found that of the 1975 children surveyed, 37% of children spent less than half an hour a day playing outdoors after school, and 43% spent more than 2 hours a day on screen time (i.e. watching TV, videos or playing computer games).

The story is similar from most urban places round the world. In the US, between 1997 to 2003, studies have documented a 50% decline in time that 9-12 year olds are spending outdoors. Issues of safety, both working parents, lack of parks and natural surroundings in our bleak urban landscape and the lure of the TV and computer are important reasons why children are spending more time indoors. Richard Louv, in his book "Last child in the Woods," has coined a new term "nature deficit disorder" which includes a range of behavioural problems. He argues that sensationalist media coverage and paranoid parents have literally "scared children straight out of the woods and fields," while promoting a litigious culture of fear that favours "safe" regimented sports over imaginative play.

In the US they have now launched a public service mass advertisement campaign "Leave no child indoors". The campaign is aimed at tweens ( 8-12 year olds) to foster a lifelong interest in and love of nature. Besides improving their physical and psychological health, it will make them more environmentally conscious’.

Source: Scientific American, 4 August (2009).

 

Benefits of outdoor play

It is generally well understood that outdoor activity is beneficial to physical and mental health, in adults as well as children. For example:

  • By providing the setting for exercise, sport and other activities that improve fitness and strength (Planet Ark, 2012).
  • Time spent in nature can provide a simple intervention which addresses a range of paediatric mental and physical health issues such as obesity, ADHD, vitamin D deficiency and mental health problems (McCurdy et al., 2010).
  • Exposure to sunshine promotes synthesis of vitamin D, which is important for strong bones, muscles and overall health (Victorian Government, 2012).
  • Outdoor play can be beneficial for eyesight. The Sydney Myopia Study found that high levels of outdoor activity were associated with low levels of Myopia (short sightedness) as outdoor activity provides a more stimulating setting for a range of eye activities, compared with indoor ‘near work’, activities such as computers and electronic games (Rose et al., 2008).
  • Many of the other benefits of outdoor play are less well understood. Childhood is a period of rapid physical, mental and emotional development, and time spend in nature provides a diversity of experiences important to the human development process. Nature provides high levels of the necessary mental and sensory stimulation, and engaging with diverse and unpredictable natural environments can stimulate exploration, creative play and divergent thinking (Faber Taylor et al., 2001; Brook, 2010; Koger and Winter, 2010).
  • Natural environments can also encourage resilience and flexibility, compared with more formal and constructed settings such as urban parks. Unpredictable natural settings create challenges for physical coordination and balance, and provide mental stimulation. Conversely, constructed settings tend to be typically safe and predictable, which may reduce the risk of physical injury while failing to provide the challenges of more natural settings (Planet Ark, 2012). One Norwegian study found children who played in the woods near their school performed better on tests of motor coordination than those who played in a traditional playground (Fjortoft, 2001).

There is a growing body of research supporting the benefits to children of outdoor play (Planet Ark, 2011). Some of the reported benefits include the following:

Physical benefits

  • Children who played outside every day were found to have better motor co-ordination and increased ability to concentrate (Grahn et al., 1997).
  • Outdoor environments allows children to move freely, by placing fewer constraints on children’s gross motor movements and on their range of visual and gross motor exploration (Burdette and Whitaker, 2005).

Cognitive benefits

  • It has been found that greenery in a child’s everyday environment can reduce ADD symptoms, and while outdoor activities in general are of help, settings with trees and grass were the most beneficial (Faber Taylor et al., 2001).
  • Children are more likely to encounter opportunities for decision making that stimulate problem solving and creative thinking in the outdoors, as outdoor spaces can be more varied and less structured than indoor spaces (Burdette and Whitaker, 2005).
  • Children have been found to be more likely to develop a responsible attitude toward risk through actual experience dealing with risky situations (Barker, 2004).
  • A large part of play is social, and promotes learning about vital social skills including taking turns, sharing, negotiation and leadership (Bundy et al., 2009).

Emotional well-being benefits

  • Free play has been shown to improve many aspects of a child’s emotional wellbeing, such as reducing anxiety, repression, aggression and the incidence of sleep problems (Burdette and Whitaker, 2005)
  • Mood may be positively affected not only by the physical activity itself but also by exposure to sunlight if outdoors (Wirz-Justice, et al. 1996)

The 2012 Planet Ark study reviewed the benefits to children of contact with nature and categorized them as follows (Planet Ark, 2012):

  • Benefits for mental health:
    • Reducing stress and depression
    • Increasing self-esteem and confidence
  • Benefits for the mind:
    • Improving creativity and imagination
    • Improving academic achievement
    • Reducing the symptoms of ADHD
  • Benefits for the body:
    • Reducing the risk of being overweight or obese
      • Burning energy: the nature of play
      • Energy intake: the nature of eating
  • Benefits for the environment:
    • Growing responsible adults

3.5.5 Benefits for mental health

3.5.5.1 Reducing stress

Researchers have found that contact with nature can help children, and people in general, deal with stress. For example:

  • Simply exposing a subject to visual images of nature, especially water, can produce a calming, stress reducing effect (Ulrich, 1984).
  • Natural outdoor settings have been shown to provide restoration from cognitive effort and stress (Kaplan and Kaplan, 1989; Kaplan, 1995a).
  • One study in rural US found that that the presence of vegetation near a home helped to moderate the impact of stressful life events on the psychological well-being of children (Wells and Evans, 2003).
  • A study in Spain found that children who had frequent daily contact with nature showed less stress than those not doing so, in both residential and school environments (Corraliza and Collado, 2011).
  • It has been suggested that intensive contact with nature can have long-term stress-relieving benefits, and that such experiences during childhood can provide a ‘reservoir’ of calming memories which can be drawn upon during later periods of stress during adulthood (Chawla, 1990).

3.5.5.2 Reducing depression

Research has found indirect associations between increased depression and decreased time spent in nature (associated with increased time spent consuming media); time spent in nature is an important factor in the prevention of mental health issues (Planet Ark 2012). Time spent watching television exposes children to advertising messages leading to the ‘commercialization of childhood’ and a culture of consumerism and materialism (Kasser 2002). Children who score high on ‘materialism’ have been found to have a higher incidence of mental health issues, including anxiety, depression and substance abuse (Kasser 2005; Bee-Gates 2007).

Research has found that the psychological well-being of children can be improved by a combination of reducing negative psychological states, while accentuating positive states (Planet Ark 2012). Building confidence and encouraging healthy self-esteemhave been found to be vital factors in accentuating these positive states, which can be promoted by outdoors activity and play. For example:

  • Time spent in unsupervised nature based activities has been found to provide opportunities for exploration and risk taking, which contribute to the development of confidence and self-sufficiency (Derr 2006).
  • A US study into the stress reducing benefits of nearby nature also found that exposure to nature helps strengthen children’s self-esteem, making them more resilient during times of stress (Wells and Evans 2003).

3.5.6 Benefits for the mind

3.5.6.1 Improving creativity and imagination

Research has shown that contact with nature plays a role in children’s intellectual development, as well as their mental health. For example:

  • The experience of nature can help to improve creativity and imagination by providing a diversity of experiences providing sensory and mental stimulation. Literally, ‘the diversity of biodiversity stimulates creative and imaginative play, enjoyment, exploration and divergent thinking’ (Kellert 2002).
  • Powerful memories of experiences in nature can provide future ‘meaning, serenity and creative inspiration’ (Chawla 1990).
  • Conversely the characteristics of the built environment and of hard-surfaced play areas can reduce the occurrence of creative play. One study found that children in settings with trees and vegetation showed more creative social play than children in barren, hard-surfaced play areas (Faber Taylor et al. 1998).

3.5.7 Benefits for physical health

3.5.7.1 Reducing the risk of being overweight or obese

Childhood obesity trends

It has been estimated that 17% of Australian children are overweight, 6% are obese, and these rates are in fact rising (Australian Government Department of Health and Ageing, 2008). Overweight children also face a range of other physical and mental problems including reduced confidence and self-esteem, and increased likelihood of being a victim of bullying. Obese children also face greater health risks as adults, including risks of type 2 diabetes, heart disease, high blood pressure, stroke, joint problems, breathing problems, some forms of cancer and ongoing self-esteem issues (Planet Ark, 2012). Central to weight loss and gain is the ‘energy balance equation’ between energy intake from eating and energy expenditure from physical activity. Planet Ark suggests that ‘contact with nature can be of benefit on both sides of this equation’ (Planet Ark, 2012). A report by the Australian Productivity Commission Childhood Obesity: An Economic Perspective identified possible causes of overweight and obesity in children (Crowle and Turner, 2010). As shown on Figure 18 the authors summarized potential factors in the rise of childhood overweight and obesity.

Figure 18: Potential factors in the rise of childhood overweight and obesity.Source: (Crowle and Turner, 2010) p.53.

The physical environment is identified as a potential factor affecting childhood obesity through its influence on levels of physical activity. For example, it is argued that areas with parks and bike paths may facilitate physical activity among residents, whereas areas designed for motorised transport or with few facilities for physical activity, would not. The authors note that while ‘… there is a growing body of research in this area, there are some study limitations’  p.49. This includes a lack of consensus on how to measure the many environmental variables and the size of the area that influences an individual. In addition, people spend time in multiple geographic areas, making it difficult to identify the environmental factors that influence an individual. There is also a wide array of physical environmental factors that can be studied, and often the choice of variables is based on data available rather than any theoretical underpinning. In addition the direction of the relationships often cannot be determined due to the study design. For example more active people choose to live near parks, rather than living near a park causing people to be more active,

Links between obesity and urban form

Researchers have identified other factors which contribute to childhood obesity, in addition to the shift from outdoor to indoor play. This includes links between the design of cities, levels of outdoor physical activity and obesity. For example:

  • A NSW government report ‘Creating healthy environments: a review of the links between the physical environment, physical activity and obesity’ highlighted the influence that urban form has on physical activity, particularly the role of transport networks and facilities that encourage ‘active transport’ such as walking and cycling, by both children and adults (Gebel et al., 2005).
  • Other researchers however take an opposing stance, asserting that the densification of cities as part of a sustainability agenda has over-emphasized the health benefits of ‘walkable neighbourhoods’ and ignored other children’s issues contributing to obesity. Researchers at the University of South Australia have suggested that studies of ‘walkable communities’ rarely involve children, and there is stronger correlation with the presence of green space, rather than with residential density. Therefore changes to suburbs that improve walkability at the expense of green open space, may not be the best way to prevent childhood obesity (Kinner and Wilson, 2011).
  • A study of 3-16 year old children in the US tested whether greenness and residential density were independently associated with changes in the BMI (body mass index) of children and youth over a period of two years (Bell et al., 2008). The authors found that children living in greener neighbourhoods had lower BMI scores after two years, and that this appeared to be independent of neighbourhood density. They concluded that: ‘Greenness may present a target for environmental approaches to preventing child obesity. Children and youth living in greener neighbourhoods had lower BMI scores…presumably due to increased physical activity or time spent outdoors. Conceptualizations of walkability from adult studies, based solely on residential density, may not be relevant to children and youth in urban environments’ p.547, and 'These findings support the exploration of the promotion and preservation of greenspace within neighbourhoods as a means of addressing childhood obesity.’ p.552.

Links between obesity and outdoor play

Research linking childhood obesity and play includes:

  • The US organisation, Children & Nature Network investigated relationships between play in nature, physical activity and obesity in children. It concluded that natural areas often encourage physical activity, which helps people better maintain their energy balance, and that currently many children do not get the physical activity that they require (Senauer, 2007).
  • Researchers note that sedentary activities, such as television and electronic games, ‘squeeze out’ time available for more active pursuits (Anderson and Butcher, 2006).
  • It has been found that BMI in children is positively associated with time spent watching television, and negatively associated with time spent in outdoor play (Kimbro et al., 2011).
  • Children with better access to public parks and recreation programs were found to be less likely to have significant increases in BMI over time (Wolch et al., 2011).
  • A Melbourne study of ten-twelve year olds over a period of three years confirmed the association between lower BMI and time spent outdoors. About 200 five-six year olds and 350 ten-twelve year olds from 19 randomly selected elementary schools in Melbourne participated in this study. The authors concluded that ‘The prevalence of overweight among older children at follow-up was 27-41% lower among those spending more time outdoors at baseline.’  The authors recommended further investigation into time spent outdoors as an obesity prevention measure (Cleland et al., 2008).

Links between obesity and eating habits

It has also been found that nature-based activities can influence the ‘energy intake’ side of the energy balance equation. Findings linking childhood obesity and eating include:

  • (Bell and Dyment, 2008) explored the potential of green school grounds to promote health and well-being and to be an integral element of multifaceted, school-based health promotion strategies. They found that ‘domesticated nature’ activities can provide opportunities for active learning and improving health literacy. Green school grounds, home vegetable gardens and school kitchen gardens, such as the Stephanie Alexander Kitchen Garden Program, can help improve physical health and promote healthy eating habits. The authors highlighted ‘the growing body of evidence that green school grounds, as a school setting, can contribute to children’s physical, mental, social and spiritual well-being’.
  • In contrast, watching television can encourage unhealthy eating habits, as people tend to snack while watching television, and are also exposed to advertising messages, including those promoting junk food (Koger and Winter, 2010).

3.5.8 Promoting environmentally responsible attitudes

Research shows that nature-based experiences can influence a child’s attitudes, and that this influence can last a lifetime. One US study found an association between participation in ‘wild’ nature activities during childhood and future environmental attitudes and behaviours. Childhood participation in ‘domesticated’ nature activities was associated with pro-environmental attitudes in adulthood, but only marginally with adult environmental behaviour (Wells and Lekies, 2006). In contrast, increased time spent indoors watching television can lead to attitudes of materialism and consumerism. It has been suggested that over time excessive materialism can encourage self-centeredness and less concern for the community and the environment (Orr, 2002). It has been suggested that through nature based experiences, children form a four dimensional connection to nature (Cheng and Monroe, 2012):

  • Empathy for creatures
  • Enjoyment of nature
  • Sense of oneness
  • Sense of responsibility

Direct interaction with nature, including pets, can promote feelings of empathy, making the animal or plant worthy of moral consideration (Gebhard et al., 2003). It is suggested that when children recognise themselves as being part of nature, they develop a sense of ‘ecological self’, and the stronger this self-perception, the more likely a child is to protect nature (Kals and Ittner, 2003). It has also been shown that powerful positive memories of time spent in nature during childhood can provide a ‘reservoir of emotional stability’ in later life. For some people, these nature-based experiences provide a sense of ‘integration’ of nature and human life. This perception of being ‘part of nature’ can calm fears and provide a sense of stability amidst the dramas of life (Chawla, 1990). As discussed in the following section, responsibility for nature and pro-environmental attitudes through contact with nature can be incorporated into school and community-based environmental programs (Chawla, 2002).

3.5.9 Nature based interventions

Outdoor play and contact with nature can be incorporated into children’s health and education programs in number of ways.

3.5.9.1 Nature and health

Research indicates that nature-based interventions can be used in the treatment of certain physical and mental conditions (Pryor et al., 2006). For instance nature can be integrated into the design of health care facilities, for the benefit of not only the patient but also of families and staff (Planet Ark, 2012). One well-known study examined the effects of the view from a window on the recovery rates for adults having undergone gall bladder surgery. The results showed that those patients with a natural view from their hospital rooms recovered faster than those in the control group (as indicated by shorter post-operative hospital stays). In addition the group of patients with a natural view had fewer negative comments in the nurses’ notes and reduced use of pain killers (Ulrich, 1984). Another intervention involves horticultural therapy programs which use gardening activities for therapeutic purposes (Planet Ark, 2012). For example the horticultural therapy program at the Stephen D. Hassenfeld Children’s Center for Cancer and Blood Disorders of New York University is designed to complement other treatment options and helps minimise challenges in the quality of life for patients and their families (Fried and Wichrowski, 2008).

3.5.9.2 Nature and education

Research findings support the integration of nature based activities into school grounds and into the school curriculum. Benefits could include improved cognitive functioning and fatigue restoration caused by intensive concentration, and also the development of more environmentally responsible attitudes which may persist into adulthood. For example a study in an Australian school suggested that children choose natural green areas for play rather than commercial play equipment or hard surfaced sporting courts (Lucas and Dyment, 2010). ‘Green’ school grounds have been found to encourage greater levels of ‘light and moderate’ physical activity by increasing ‘the range of enjoyable, non-competitive, open-ended forms of play at school’ (Dyment and Bell, 2008; Dyment et al., 2009). School kitchen gardens also provide opportunities to connect with nature and learn about healthy eating (Planet Ark, 2012).

3.6 Summary

  • There is a large body of research supporting the human health and well-being benefits of contact with nature in various form, much of it by researchers in the field of medical and social science.
  • Research has focussed on three aspects of well-being: the physical and mental health and well-being of individuals, and the role of social interaction and community building.
  • Two particular groups who would benefit from Green Infrastructure in cities are older people and children.
  • Green Infrastructure which can support human health and well-being includes the provision of accessible green spaces, and green linkages and more ‘walkable’ streets.
  • Green Infrastructure can also be incorporated into medical institutions for therapeutic purposes, and into schools to foster healthy childhood development.
  • Researchers have more recently criticized the methodologies applied to measure the human health and well-being of Green Infrastructure, such as proximity to green space, emphasizing the need for more longitudinal rather than cross-sectional studies.

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