Dr Jane Tarran BSc – UTS Program Director – Urban Ecology
Click to view Dr Jane Tarran’s presentation
ROLE OF URBAN FOREST IN PROVIDING SUSTAINABLE SOLUTIONS FOR CITIES
A report,with personal comments, by Frayne Dyke-Walker.
Benefit of Urban Forest include;
- Environmental & Ecological
- Aesthetic & Visual
- Social, Psychological & SPIRITUAL Benefits – (I also bought a Fab book ‘Healing Gardens’ that discusses this in detail – from Floralegium)
- Economic Benefit to Business
I could add to this list Urban Wildlife – critters and birds, not just for the environmental and ecological benefits – but for the distressing fact that not a lot of families can now have pets, and without urban wildlife they would be even more disconnected from the other inhabitants of the planet that have just a much right to a sustainable planet as we do. ENOUGH EDITORIALISING!
Trees, Shrubs, Grasses in residential, public parks and industrial areas:
- form part of the natural capital of a city
- it’s a window into the soul of a city
- reflecting the values and aspirations of current and past residents
- it’s greenness has been found to provide soothing mental relief
This is readily apparent in garden cities like Canberra.
But it takes:
VISION (in Canberra’s case it was Marion Mahoney Griffin’s incredible work)
Planning, financial and trained resources, great management and maintenance – all integrated and working together, which again needs leadership and vision.
(I also think it needs to be fed with appreciation, respect and passion – in addition to money.)
Urban Forestry is equal parts Art, Science and Technology. It is not just about shade, keeping tar seal cooler to reduce green house gas emission from parked cars, or cleaning particulates from the air, providing passive solar solutions seasonally, or being the lungs of a city – cleaning the air as we pollute it.
History of Urban Forestry:
Became a recognised sector within traditional forestry during the 1960s in the USA when the disastrous Dutch Elm Disease threatened 90% of the street, park and landscape trees.
Chicago particularly started UF research projects (Chicago Urban Forest Climate Project), the results drove increased education and it has since spread around the globe. Unfortunately Australia has not managed to catch on to the significance of this activity locally and is yet to finance the resource to do these sorts of studies. China with the Beijing Olympics coming up has been particularly quick to take up this important research. Here Dr Tarran’s finely honed irony came to the fore – “We obviously will be able to import experts from another country when we need them . . .”
Why do we need Urban Forests?
Because of the increasing URBANISATION of all cultures. UF provides food, ornament, recreation and shelter.
Dr Tarran quoted E.O. Wilson “Subconscious connection to the rest of life – ‘biophilia’ ” – Every one in the room sighed – it was magic – we are recognised – we are a tribe of biophiles or biophiliacs!!! Eureka! Apples dropped, lightbulbs flashed on – we all looked at one another and smiled and nodded – a great defining moment in the afternoon.
Humans have an innate preference for savannah like parkland – our collective psyches need a few trees for shelter – but not too many to feel threatened or at risk from hidden predators. We’re obviously tribal but with a tendency to the herd instinct like the herds of the savannahs – safety in numbers.
Research has shown we are basically divisible into groups; (This section was rivetting for me)
- Love for and dependency on nature – the wilderness dwellers
- those that find renewal in nature and have to have periodic contact with nature
- those that like to tame nature – higher density populations, regular out door recreation areas and often motorised interaction with nature (boat, car, bikes, planes)
- nature neutrals – not fussed one way or another (how have these people come to disconnect from the planet or their life?)
- nature haters – actively hating something that isn’t capable of hating in return – it may not be benign but … (why and how can this happen? are they terribly scarred because of a life experience or is it some instinctual fear that overrides reason?)
- people afflicted with plant blindness – an inability (disability) to notice or recognise plants. (Then I remembered those awful reality tv shows where whole families didn’t recognise vegetables and fruits because they’d never eaten or cooked them – why am I so surprised?)
The building blocks for Urban Ecology;
Ecological models from natural areas applied to urban areas.
Humanities/ Social Sciences/ Natural and Physical Sciences
are developing new roles and strategies to cope with increasing urbanisation of the world’s population.
50% of the population in 2000 lived in urban areas
66+% an increase of more than 16% in five years had moved or been born into urban areas
We are looking at the largest human migration in history.
So what does this mean for the Ecology of Urban Areas apart from the sheer insult of increasing numbers of a smaller piece of territory?
Global Warming impact is greater in a smaller area -
Temperatures – Heat Island effects
Rainfall – the wider extremes of flood and drought – everyone has experienced that one locally over the last three months.
Soil moisture/air
Fire
El Nino – La Nina oscillation
All are combining for more extreme events – more heatwaves, cold snaps, wildfires, landslides, storm surges, droughts, dust/particulates.
(For the climate sceptics left over from the last political administration – A timely reminder that even Michael Hawker from IAG (Insurance Group of Australia) is concerned enough to be working with the previous speaker Frouke de Reuver from the DECC Business Partnerships Program).
All this adds up to increasing vulnerability for;
Water resources
Ecosystems
Agriculture
Coastline
Forests
Settlements
So this greatest migration in human history is taking with it GHG emissions into smaller more consolidated areas putting icnreasing pressure on existing Urban Forest islands – Can it adapt and deal with;
temperature fluctuations?
air quality?
sequestering of CO2?
stormwater and catchment?
(Makes me worry about the load on each remaining tree – How would you feel rooted to the spot getting older with the pressure of work increasing until the day you die? No retirement, only brief respites in the onslaught of some of the stressors on the weekends and only in some areas? Be good to have a community to share the load and get a bit of regular food, maintenance and appreciation at least for shouldering the load 24/7)
All the while expected to provide;
Shade to protect, people, cars, roads, surfaces
Windbreaks and evaporative cooling
Air cleaning and water slowing duties
Habitat etc
Thank heavens power utilities in California in the US have spent the money on research about how to utilise their existing energy production more effectively and sustainably and not rush out and build another GHG emitting power station – AND have shared the results:
Well placed trees on western aspects can make considerable (90%) energy savings for peak heating and cooling seasonally.
So power utilities instead of being keen to massacre trees are now encouraging them – and putting their cables underground. An expensive one off cost, but the benefits long term are now proven and are starting to stack up.
Strategic trees can mitigate urban heat island effects by providing shade, evapo-transpiration, help improve air quality by collecting particulates, trap gases, reduce hydro-carbon emission from parked cars, stormwater catchment (slow flows, reduce runoff rates and soil erosion).
Even US air conditioning companies are now researching how they can use the natural world’s principles to improve air conditioning.
Research into the aesthetic and visual benefits of Urban Forests is showing profound social and psychological benefits from the restorative power of nature.
The therapeutic effects on individuals and resultant the flow on helps communities flourish. One can’t doubt the beneficial and soothing capabilities of UF on mental fatigue and information overload, we know it and feel it – but now it is being qualified and quantitified.. .
References:
Rachel & Stephen Kaplan
Roger Ulrich – 1984 – surgical patients recovery times in hospital with views of parks/gardens versus brick walls
Moore – 1981 – prisoners in a variety of environments
Kaplan – 1993 – workplace environments. Employers who value staff and productivity levels are particularly aware of this research
Parson et al 1998 – drivers on the roads
Wells – 2000 – children and housing
Francis Kuo & Sullivan (HERL) – Chicago – following on from the original Chicago Urban Forest Climate Project found that there is a correlation between
Canopy and Crime – Green Street not Mean Streets
Vegetation and Violence – greener areas are safer from domestic violence
Studies also it was found that children with ADD an increasing section of the population benefit from going outside and playing before going inside and attempting tasks requiring concentration. Natures Adds Up for ADD. (A teacher once speculated to us that it was probably a genetic response to our evolving environment)
Girls and Greenery – Views of green and natural environment helped cognitive function develop in girls.
(More editorialising – makes such perfect common sense that you really have to wonder why it isn’t such an intrinsic part of our culture and values – it used to be – that’s how places like Centennial and Hyde Park were created – but what happened in the interim? – You see the lack of budgets for public parkland restoration, yet you see malls driving a consumerist society – No wonder we need the Humanities/ Social Sciences/ Natural and Physical Sciences all together).
Growing Beyond
Urban Forestry is not just about trees in the landscape is spreading to the top of the built environment. Rooftop gardens, garden walls, interior plantscapes often with solar access into buildings, community gardening for food and pleasure and leisure are just a few other developing directions.
Challenges include;
Soils,
Microclimates
Species selection
Temperature ranges
Rainfall
Wind
Physical limitations -
Necessary biodiversity
But Urban Forestry is an increasing necessity – requiring stable environments to thrive, appropriate management, and protection from incremental damage.
We have to bite the bullet and get the cabling underground, allocate more space for urban forest rather than barely leave enough space around our developments for roots and canopy. Dr Tarran’s reference to developer Harry Triguboff wanting people to drive to Katoomba to see a tree has a frightening reality as I drive to a friends property in Mt Irvine after the seminar. ‘If we don’t become more proactive that will be the reality
As she says ‘Most importantly we have to measure and map the existing Urban Forest – If it isn’t counted – it doesn’t rate!’
“Talk to the engineers about how we can make the Urban Forest part of the city environment. After all it is the 100th Anniversary of Underground Power in London this year.”
A fabulous speaker – inspiring – a true biophile
