Green Infrastructure Evidence Base

2.2 Definition of key concepts

The following section provides definitions of some of the key terms included in this report. More detailed definitions may also be included in the relevant sections.

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 comprises not just the benefits gained from psychological and physical health, but is also related to specific aspects of well-being such as favourable thoughts and feelings, satisfaction with life, ability to be self-sufficient and proactive, possessing a sense of happiness, and a positive evaluation of life in a general sense (Diener, Suh et al. 1999).

Nature. Maller et al. (2006) define 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 (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.).

The concept of ‘nature’ is in one sense a human construct, reflecting societal and individual value systems. Discussing the ‘ethics of sustainability’ Thompson (2000) reviews the different human attitudes to nature and environmental ethics. He identifies the following typologies or positions within environmental ethics:

Anthropocentric position

  • Ego-centric. Self-interest.
  • Homo-centric. The greatest good for the greatest number. We are responsible for stewardship of nature for human use and enjoyment. Non-anthropocentric position

 Non-anthropocentric position

  • Bio-centric. Members of the biotic community have moral standing.
  • Eco-centric. Ecosystems and/or the biosphere have moral standing. We have a duty of care to the whole environment.

Aldo Leopold’s (1948) Land Ethic is an early statement of the eco-centric position, as is McHarg’s (1979) philosophy of Design with Nature, and James Lovelock’s (1979) Gaia hypothesis. In his book Man's Responsibility for Nature Australian philosopher John Passmore (1974) argued that there is urgent need to change our attitudes to the environment, and that humans cannot continue the unconstrained exploitation of the biosphere. However his case for environmental stewardship rested on an anthropocentric viewpoint, of valuing nature in terms of what it contributes to human well-being rather than attributing an intrinsic value to nature, as advocated by the ‘deep ecology’ movement.

The Urban forest

The urban forest has been defined as ‘the sum of all publicly and privately owned trees within an urban area, including street trees, trees on private property, and remnant stands of native vegetation’ (Nowak, Noble et al. 2001; Miller 2007). The urban forest is an integral part of the ‘urban ecosystem’ in which a wide range of physical and human elements interact to influence the quality of urban life. The concept of urban forestry is widely adopted in the United States and Europe (Konijnendijk 2008), and more locally a number of councils have developed Urban Forest Strategies. Notably the City of Melbourne has recently completed a major strategy for the sustainable management of its urban forest (City of Melbourne 2011). Brisbane’s urban forest strategic planning, targets, policies and programs are focused on optimising the multiple benefits of the extensive and diverse public and private tree cover whilst balancing the risks, costs and other priorities of a growing city (Brisbane City 2013a).

National Urban Forest Alliance

The National Urban Forest Alliance NUFA (2013) has recently been formed to ‘promote a thriving, sustainable and diverse Australian Urban Forest that creates a contiguous and healthy ecosystem that is valued and cared for by all Australians as an essential environmental, economic, and community asset’. Its goals are to ‘develop, partner trial and implement systems, programmes, communications, guidelines, landscaping and infrastructure to grow the Australian Urban Forest’. Values of the Urban Forest include:

1. Reducing greenhouse emissions by sheltering nearby buildings from sun and wind.
2. Reducing the urban heat island effect in a time of climate change to improve liveability and comfort.
3. Improving air quality for our atmosphere and water quality for our waterways and bays.
4. Sequestering carbon from the atmosphere to help prevent climate change.
5. Increasing habitat to support biodiversity.
6. Providing food such as fruits, nuts, spices and olives.
7. Increasing the life of infrastructure through weather protection.
8. Improving the visual amenity of streetscapes and neighbourhoods.
9. Increasing real estate value of properties with tree lined streets.
10.Improving the health of residents by encouraging them to walk and be more active.

Current Stakeholders include but not limited to:

• Arboriculture Australia
• Brisbane City Council
• Nursery & Garden Industry Australia
• Parramatta City Council
• Australian Landscape Industry
• Campbelltown City Council
• Parks & Leisure Australia
• Darwin City Council
• Melbourne City Council
• Launceston City Council
• Sydney City Council
• ENSPEC Pty Ltd