A recent study, published in Science Advances, has found that urban green spaces contribute a range of important benefits including microbial communities that are critical to sustaining productive ecosystem services, as well as mental and physical benefits for residents.
“Parks are not the homogenised ecological deserts that we think they are – they are living ecosystems that do amazing things,” study co-author, Professor David Eldridge from the Centre for Ecosystem Science in UNSW Science’s School of Biological, Earth and Environmental Sciences, said.
“Urban greenspaces harbour important microbes, so if you want to sustain a bunch of ecosystem services, you need to have plenty of parks and green spaces.”
The study took soil samples from different types of urban green spaces and comparable neighbouring natural ecosystems in 56 cities from 17 countries across six continents.
The urban greenspaces studied included Olympic Park in Beijing, the University of Queensland campus in Brisbane, Retiro in Madrid Spain, and the park surrounding Uppsala Castle in Uppsala, Sweden.
With 68 per cent of the global population set to live in cities by 2050, the study suggests that urban green spaces are critically important for promoting mental and physical wellbeing.
Parks and gardens make up most of the open spaces available for recreational activities such as sport and social engagement, and play important roles in curbing pollution, reducing noise, and lowering air temperatures, the study said.
Moreover, human exposure to soil microbes has been shown to be beneficial to human health by promoting effective immunoregulation functions and reducing allergies.
Dr Eldridge said the results mirror a study in Central Park in New York, which found there was as much microbial diversity in the city park as there is globally.
“City parks harbour a range of microbial communities that are different to natural ecosystems,” Dr Eldridge said.
The study found that even road verges were full of important microbes.
“We think of roadsides as being barren, but we found a great variety of different microbes in some roadside verges; they are not barren wastelands at all,” Dr Eldridge said.
“Some European cities such as Bern in Switzerland have a policy to protect the natural vegetation along footpaths and roadsides.
“These pathways then become mini-green spaces, linking larger green spaces. We need lots of different microbes, and to get this, we need a variety of landscapes such as median strips, parks, and nature reserves.”
Lead author, Dr Manu Delgado-Baquerizo from the Universidad Pablo de Olavide in Spain, said the study found that urban green spaces from all over the world are very similar.
“They often have lawns, and similar management practices, which tend to homogenise the microbes living in different global cities,” Dr Delgado-Baquerizo says.
The international study is part of a series of research looking at the importance of green spaces for ecosystem health. The next study will examine the importance of mosses in urban green spaces for supporting healthy soils and important habitat for microbes.