Urban green spaces like backyards, city parks, and golf courses contribute substantially to the ecological fabric of our cities—and the wider landscape—and they need to be added to the data ecologists currently use when exploring big questions about our natural world.
In a study published on Wednesday (6 March) in the journal Ecosystem Applications, Carly Ziter, a graduate student at integrative biology professor Monica Turner’s lab at the University of Wisconsin-Madison, took soil samples from 100 sites around the city of Madison, Wisconsin.
To get a sense of how urban areas fit into bigger landscape dynamics, Ziter surveyed cemeteries, the UW Arboretum, public parks, and lots and lots of backyards. Each sample was then analysed for three ecosystem services: carbon storage, water quality regulation, and flood mitigation.
Findings of the study indicate that urban green spaces play a significant role in providing some ecosystem services.
“Often when we’re doing regional studies of ecosystem services, or the ways that nature benefits us, we ignore the cities,” said Ziter. “We treat the city as this kind of grey box; quite literally on maps, it’s often a grey box. And what we’ve discovered here is that…we need to be thinking about the city as part of the landscape,” she added in the initial statement of the study.
The researcher found that more developed areas like public parks and people’s yards store substantially more carbon in their soils than urban forests or grasslands. Urban soils even stored more carbon on average than the agricultural soils that dominate Madison’s surrounding landscape.
The paper points out that urban forests and grasslands have a big impact on flood control, allowing water to infiltrate into the soil instead of simply running off into streets or storm sewers. Also, the kind and magnitude of service being provided varied from site to site.
Ziter further said, “my front yard and my backyard can be more different in terms of their ecology than two houses across the city from one another. And that’s really fascinating from a management perspective, because it’s these small decisions people are making as individuals that are shaping the ecology of these landscapes.”
She hopes her study can help in highlighting the importance of urban green spaces and encourage more ecologists to start studying these urban environments.