How should we characterize urban nature? Perhaps a useful starting point is to distinguish between produced nature such as gardens, parks, and tree-lined avenues and spontaneous nature that simply co-exists with us such as foxes, swifts, or weeds. It is certainly the case that interest in spontaneous nature has grown rapidly in recent years, as part of a surge of interest in urban bio­iversity. The Covid-19 lockdowns, for example, encouraged a discovery of nature on «our doorstep». The reduced noise from road traffic made birdsong more audible. People taking walks near their home began to notice traces of nature they had previously overlooked such as brightly flowered weeds growing by the roadside. Many commentators stressed the mental and physical health benefits of contact with nature.

A number of scientists and policy makers now recognize that levels of biodiversity in cities are not only very high but also often greater than in monocultural urban hinterlands. In contrast with modern agricultural landscapes, for instance, cities contain multiple biotopes such as cemeteries, walls, and wastelands. Urban ecologists have sometimes emphasized these unusual sites as «novel ecosystems» which comprise fauna and flora from all over the world. In this sense urban nature can be characterized as a series of «cosmopolitan ecologies» that contain traces of global history. Studies of ballast flora in ports, for instance, is a living record of former trade routes including botanical traces of European colonialism.

How is urban nature conceptualized? There is now a huge and growing literature on urban nature but it is useful to highlight four main perspectives. A first dimension is what we might term «systems-based approaches» that tend to regard nature as a series of measurable phenomena that can be designed or controlled such as the flow of water through infrastructure networks or the construction of new parks. A second vantage point is that of «observational paradigms» which we can trace back to nineteenth-century fascination with birds, plants, and other organisms in cities and now connects with emerging interest in «citizen science» and new ways of collecting scientific data. A third perspective, dating from the 1990s, is that of «urban political ecology» which emphasizes connections between polluting or health-threatening human environments and the need to connect nature with social justice. And most recently we can add a fourth dimension, linked to interest in the «multi-species» city, which emphasizes the social justice dimensions to polluted or health-threatening human environments.

One of the most interesting questions to consider is whether different elements of these existing approaches might be combined to provide the kind of insights that can foster a new kind of environmental citizenship. An interest in «forensic ecologies,» for example, might effectively combine observational approaches, such as the use of lichens and other biological sensors to monitor air pollution, with aspects of political ecology that have revealed the speculative dimensions to the production of urban space. Equally, an emphasis on how to live with non-human others might be extended to a fuller engagement with hidden dimensions to agro-capitalism and the treatment of animals in food production. After all, some of the most serious threats to human health are zoonotic in origin. A more nuanced intersection between theory and practice offers possibilities for an enriched public culture that can build new kinds of social and environmental alliances. Cities can be conceived as laboratories for the future.

Matthew Gandy

For me, Park am Gleisdreieck is an extremely interesting new public place because it’s being built out of an effectively postindustrial landscape, and infrastructure landscape from former railway lines, and it incorporates these interesting pockets of ruderal ecologies. But it also creates some completely new ones. It has this interesting mix of artificiality and staged urban nature, but also genuine fragments of what was here before. This park is very interesting from a design point of view as it links directly to the Institute for Urban Ecology at the Technical University Berlin.

Dorothee Brantz

And you can still see some of the leftover spaces, like the rail lines. It fits into a larger sort of development in Berlin, but also elsewhere of turning former industrial sites into parks. Südgelände is another example for Berlin. But we also have this in many other cities. Is there a kind of global dimension to this kind of reconstitution? Especially, these kinds of former railroad infrastructure spaces into green spaces.

MG

Yes, I think so. Obviously, Berlin has been leading the way in certain respects. But in other cities—London, Paris, Montreal—you have examples of these former industrial spaces or infrastructure spaces turned into very innovative public parks. And it’s quite ambiguous because on the one hand, it’s a kind of celebration of urban biodiversity and urban nature. But it’s also become recognized as a very clever way of raising property values and regenerating particular urban districts.

DB

I was also thinking that it is covering up histories in many ways. Maybe not so much in these industrial areas, but when we think about Berlin, we have these covered up spaces of the Nazi Era. If we think of for instance the Teufelsberg, we have the Nazi Military Academy that was to be a part of the University underneath. And then they built a rubble mountain on top of it, and then a spy station on top. So, it shows the history of the city and its development, it kind of documents the integration of green spaces into political ideologies.

MG

I think that’s a really interesting point in the way that vegetation can hide the past. It can also at the same time reveal the past, in the sense that certain plants are indicative of former human activities or traces of global history. So, there’s this ambivalence about the relationship between vegetation and ecology, and urban history.

DB

Teufelsberg, if you walk up there, if you scrape a little bit with your foot, the rubble is coming up and you can see it on one level. But for instance, during World War 2, all kinds of new plants were being brought in right on the wheels of the tanks. So, there’s this constant in-migration, too. That’s brought through human movement, global trade. We always have that. New animal species arrive and new plants, some of them intended, some just arrive on their own accord. So, you also know a lot about animals, right? And it’s always important not to think of green spaces as just plants. What sort of notable temobe brackets around species are here?

MG

If you have a park like here, where we’re sitting now, Park am Gleisdreieck, there is a complicated situation because it’s quite successful at protecting or enhancing ecology but less so in relation to the social complexity of this area because most people rent in this part of Berlin and rents, of course, have risen in response to this extremely successful and very well designed green space in the immediate vicinity. And that is a dilemma which I think is often absent from an architect’s point of view or planners’ point of view. It’s not satisfactorily addressed. And landscape designers would say our job is to produce an amazing space and we we’re not responsible for the structural dimensions to capitalist urbanization. But that answer isn’t enough. I think we have to look at an integration.

DB

And nothing is to say a one-to-one connection that more green spaces means gentrification. I mean, everybody should have a right to green spaces. The right to the city shouldn’t be sort of connected to who can live near a park. If we think of Martin Wagner [German architect & city planner, 1885–1957] at the turn of the 20th century right here in Berlin who said everybody should have access within walking distance to green spaces independent of their economic position or class. So, we need to get back to that too where it’s not equated with gentrification.

MG

Martin Wagner explicitly wanted to connect the new electrified S-Bahn system to these bases of nature on the urban fringe, Wannsee and Schlach­tensee, and these other very popular lakes. So that was part of his overall vision for nature in the city.
DB Having lots of them at different places all over the city to not just have these large green spaces where it takes a long time to get to. I think this is something that we’re getting to more and more, not just the park as an isolated green space but these sort of park systems, which is something we already had in the 19th century Frederick Law Olmsted [American landscape architect, 1822–1903] was really trying to have that kind of urban understanding and we are getting back to that to see who travels the city. The animals who travel the city, they need corridors to go through. So, I think that’s something where we need to think about urban green spaces as a whole cover of the city and not just contain spaces.

MG

Rather than parcels of green space we can consider interconnected networks or corridors. I think something that is happening in Berlin and other cities is an attempt to connect between different parks. I know Park am Gleisdreieck is being connected to the same former infrastructure system that leads to Südgelände, and I think we will be there very gradually step by step. They’re trying to connect these spaces together with new sorts of walkways, cycleways, and things of that kind. So that’s quite an imaginative approach, to think of the networked green city.