Urban ecosystem services
When researchers warn that 60% of the land expected to be used for urban development by 2030 has yet to be built it is enough to make any environmentally concerned citizen go into a permanent state of worry.
But the enormous change currently happening, with the majority of the global population dwelling in urban areas, also represent unprecedented opportunities.
As researchers at the centre has often pointed out, this enormous challenge can be turned into opportunities and show why urban ecosystems services are so important for our climate, our wallets and our health.
In a paper recently published in Current Opinion in Environmental Sustainability, centre researcher Thomas Elmqvist and colleagues from several universities show that investing in green infrastructure and restore ecosystems such as rivers, lakes and woodlands in urban areas may not only be ecologically and socially desirable, but also economically advantageous in view of future climate challenges.
The study argues that even in highly degraded urban areas, restoration is possible.
"Urban soils are often polluted and lacking important microbial organisms for plant growth but thanks in part to innovative use of organic urban waste and urban adapted knowledge, recuperation can often be highly successful"
Thomas Elmqvist, co-author
Big benefits, conservative estimates
Using data from urban forests and woodlands from 25 urban areas in the US, China and Canada, Elmqvist and his colleagues show that these forests and woodlands provide financial benefits such as air pollution reduction, energy saving and storm water reduction worth up to US$17772 per hectare per year and over time annually generate a revenue that offset the cost of restoration by a factor of 2-6.
And this is not including the ‘insurance value’ ecosystems can offer by helping cities deal with storms, flooding and sea level rise.
However, these estimates also exclude some very important benefits, according to Elmqvist.
"These estimates clearly underestimates the full value because they do not include values that are difficult or impossible to put a price tag on, such as positive health effects and human well-being," he says.
"We know that access to green space in cities may correlate with reduced stress, improved mental health, faster recovery from surgeries and even self-reported perception of health, all which may translate into higher well-being," Elmqvist explains.
Not capturing all benefits
Furthermore, green urban areas provide a meeting place where users develop social cohesion and maintain neighbourhood ties.
Research on allotment gardens in Stockholm revealed a strong sense of place and emotional bonds to their plots and the surrounding garden areas. Urban ecosystems also provide opportunities for cognitive development and education for young children.
Elmqvist explains that investing in restoring and enhancing urban green infrastructure and ecosystem services is not only ecologically and socially desirable, it may also often be economically viable.
"But even though economic calculations of ecosystem service benefits may provide useful arguments in urban planning where land is highly contested, we have to remember that these estimates do not fully capture all benefits of restoring ecosystem services in cities, including multiple health effects and many other dimensions of human well-being. Much further work on these dimensions is needed,” Elmqvist concludes.
Elmqvist, T., Setälä, Handel, SN., van der Ploeg,S., Aronson, J., Blignaut, JN, Gomez-Baggethun, E., Nowak, DJ Kronenberg, J. and de Groot, R. 2015. Benefits of restoring ecosystem services in urban areas. Current Opinion in Environmental Sustainability, 14:101–108 http://dx.doi.org/10.1016/j.cosust.2015.05.001
Thomas Elmqvist is a professor in Natural Resource Management. His research is focused on ecosystem services, land use change, urbanization, natural disturbances and components of resilience including the role of social institutions.