Parks: not just for people
While our parks are tailored for human benefit and enjoyment, this overlooks the complex interactions that underlay even the most basic ecosystem, writes postgraduate student Manuel Lequerica.
Manuel Lequerica is biologist and natural resource economist. He completed a BSc (Biology) in Colombia with a major in the ecology of tropical high montane forests. In 2013, he finished a Master of Agriculture at The University of Sydney where he studied the economic efficiency of sewage treatment plants in NSW. He is a postgraduate student in the School of Life and Environmental Sciences' Integrative Ecology Lab, where he analyses the effects of urban growth on wildlife, especially plants and insects.
The Lotterywest Federation Walkway glass bridge in Perth's beautiful Kings Park. This 500Ha urban green space is the perfect meeting point between recreational space and wildlife reservoir.
Imagine sitting in the shade of a tree during summer, watching a spoonbill duck among the long grass at the edge of a wetland. The sound of traffic and construction is muted by the green space around you. Green spaces are great, and we all know that. But why? According to this post in The Conversation, they can improve your concentration and make you a sharper, more creative thinker. Green spaces can also reduce your stress, anxiety, aggression and even improve personal satisfaction; that is, in other words: they make you happier.
We cannot forget that thousands of creatures used to roam freely (or not, in the case of plants) in the very same place where you are sitting right now, reading this.
Perth's CBD seen from the Botanic Gardens in Kings Park.
Cities around the world make a big effort not only to meet the WHO minimum of 9m2 of green space per person; they are actually trying to get as green as they can. And they should. Quito hosted the III United Nations Conference on Housing and Sustainable Development, Habitat III, last September. The take-home message regarding green spaces is clear: they can minimise carbon emissions, act as sustainable drainage systems, regulate temperature, and provide habitat for wildlife.
But let's make things clear: not all green spaces are the same. Our parks have been tailored for human benefit and enjoyment, forgetting the complex interactions that underlay even the most basic ecosystem. Urban parks have perfectly mowed lawns, gardens bursting with beautiful flowers that pop-out from exotic plants, and paved trails that take you in circles. This is fine but probably unsustainable.
Green spaces are tailored for human comfort and convenience. Tables, grills and mowed lawns are the usual scenery of most parks.
Plants- we have been told- are primary producers and provide food for the herbivores and frugivores that, in turn, feed the hungry carnivores. Detritivorous creatures decompose all dead things, returning valuable nutrients back into the system; we call it recycling. When all these groups of living things (animals, plants, fungi, bacteria, and viruses) interact with their non-living environment, a broad range of ecosystem services is generated, and humans rely on these services to survive on planet Earth.
We cannot forget that thousands of creatures used to roam freely (or not, in the case of plants) in the very same place where you are sitting right now, reading this. However, they relied on a complex ecosystem that has been heavily modified by our city-building frenzy. The bottom line is that ecosystem services provided to city dwellers are quite limited, and this is a concerning affair.
Professor Dieter Hochuli telling urbanites about the importance of a remnant Banksia Scrub in Sydney Park.
We have displaced wildlife from their natural habitats, but green spaces are our opportunity to bring them back, along with the ecosystem services they provide. One of my goals at The Integrative Ecology Lab is to understand how urbanisation affects wildlife and to restore ecosystem function in urban green areas.
Two young urbanites conduct an insect survey in a no-mow zone at Sydney Park. These areas provide shelter and food for many species of animals, improving biodiversity.
That is what I have been doing for the last year, and I've made a couple of exciting discoveries that can transform our urban areas into more sustainable spaces. These are a few:
1. Larger urban green areas have increased biodiversity. Biodiversity has positive effects on most ecosystem services (at least on the ones that can be quantified)
2. Green areas with more vegetation diversity have highly diverse insect communities. These insects provide ecosystem
3. Green areas with more native vegetation and less artificial infrastructure provide shelter to more species of native insects.
Shocking contrast between a highly modified green space (left) and a more natural one (right). Plant debris and native vegetation can support a more diverse biotic community. These two sites co-occur at Perth's Kings Park, showing us that both views of green spaces are fully compatible.
Research in urban ecology reminds us that green spaces play important roles at multiple levels. Cities are on the right path by protecting and building green areas, but we have to remember: parks are not only picnic sites. It is time to change some landscape paradigms: un-mowed patches of grass, native vegetation hedges, and plant debris are not ugly; they are home to many species whose presence help to increase biodiversity and enhance ecosystem services. Let's bring life back to cities and enjoy all that it has to offer.
This article was originally published on Manuel's blog Will there be something for dinner?
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