Jan Albert Šturma
(transcript of the lecture, conference On a different soil. Growth in art, society and culture, Nová scéna, Prague, Nov. 10 - 11, 2011)
In the first place, I would like to talk about why is the city vegetation so interesting, and also about its general patterns. At the beginning, I mention the nature of the city landscape, and because I am a botanist, I will focus on vegetation, more or less on plants. But because vegetation only doesn´t present all the important phenomena of the suburb landscape, I will also help myself with sociology and urbanism. In the second part, I'll try to briefly describe - using the knowledge I will mention in the first place as a guide - where to live in the open space of the city, how we can use the vegetation knowledge to live like - although I don't like the term - so called homeless people. The last part will be about two projects of mine, and at the end I will also mention, what the nature conservation says about the suburban city vegetation.
Intentionality, conservativeness, zonality
The area I will talk about is the big region of Prague, including the small city Kladno, which is almost purely industrial; proportionally much more than Prague.
When talking about the city vegetation, we will use some particular terms to clasiffy the main „axes“ of (botanical) diversity in the urban areas (this concept comes from statistical multispacial data analysis, projecting each direction of variability as a separate dimension).
In my opinion, the most important factor is intentionality. It means, that in the city there are places where the vegetation is almost hundred percent planted, for example various gardens; but - on the opposite site - also a true wilderness: it means places, where nature does everything on its own (despite almost exclusively antropogenic origin of these places).
The other term is conservativeness. Differrent plant species have different site preferences, derived from their life strategy and growth form. This is very important, because it shows for how long the place where the plant grows persists. If it is only one or two years, like some dumps or waste areas, or if it is for centuries, like the old parks, woods or rocky cliffs. This means, that the conservative structures are usually dominated by trees or other long-living plant foms, and the dumps are more suitable for annuals or biennials.
The last dimension is zonality. My question is: is there a clear difference between the city edge, centre and open countryside? Are there any visible zones there? Can we observe something similar as in the mountains, where there are different vegetation „stores“ or „levels“ depending on the attitude?
Between natural and ruderal
Concerning the general patterns I was talking about, the city comprises very large scale of very different biotops, which are not only different by appearance, but also due to their history. Most of them are commonly classified on the scale between „natural“ and „ruderal“. There are almost no pure cases. All of these biotops can contain an enormous amount of plant species. For example Prague: more than a half of the total number of species of the Czech Republic grow here in the city and in its suburbs, so it is extremely rich. Also, some of the biotops have very exotic look. We never know the number exactly, because it is changing continuously (new ones are continually being introduced and others extinguish).
But except of the patterns I was talking about, there is a general pattern, which we could observe from the satellite, or from the maps, and which could be described as evoluting mosaic filled with „grains“ lying on a gradient between conservative and highly dynamic structures.
Here you can see the difference in use of the land in the 1990 and 2006. It is very rough, but still it tells us something about the landscape. Red symbolizes urbanized areas, which are spreading aggresively. Not only the urban area, which is inhabited, but also the violet spots - shopping centres or factories. White ones are the arable fields, which are being slowly diminished from the city, except from some rare cases.
The conservative structures remain in the cities sometimes for centuries. In Prague, it could be for example Petřín, the hill, of which some parts have been forested for a very long time. Those places have some kind of a long-term memory. The memory is for example manifested in the shape of a biotop, or in the plant species living there. Trees, but also herbs, could persist there for centuries. And the highest density of these structures is in the city centre, because it doesn't grow, it doesn't change very much.
There will be two examples: the old cemetery, one of those conservative structures in Olšany district; anohter one is park Letenské sady in the centre of Prague. These are the typical conservative structures. We also have some very conservative structures, which are located in the nature conservation sites. As we can see on the map, none of the nature conservation sites is in the centre of Prague. Nature conservation is not able to evaluate or classify the old antropogenic and „strange“ sites and biotops, and thus gave up and said, it is just space for urbanization.
…and dynamical structures
On the other pole of the gradient, there are the dynamical structures. Now I am talking about the more interesting part of the city landscape - brownfields, heaps, which are usually very young and disappear very quickly. They have very high cover of bare soil, and they are typical for the suburban areas. These are extremely rich and very cosmopolitan plant species; they could be coming from South America, Africa, from almost anywhere, except Antarctica; and they have a very short „memory“, due to very common “deleting”: due to the removal of the buildings, progress of succession, or by so called cultivation.
Here is one example from the eastern edge of Prague, which is only one year old, and you can already see very strange erosion. There are some very interesting plant species growing on it, like Chenopodium botrys, which looks very nice and decorative. Sometimes there are very rare species like Polycnemum arvense to be found, which is extremely rare and also nice. This is an example of a kind of suburb with invasive species from Southeast Asia, which spreads very quickly and which is very strong there.
Recognizing the suburb
Now would like to talk about zonality. Are there any differences between the zones? They are quite clearly visible, and the vegetation is different. I am talking about the general pattern, so it doesn't mean that there are no islands. Usually there is no sharp border, but there is a difference. The most interesting (from biological, but also other points of view) is the zone between the conservative centre and rural countryside. This area is called periphery, city edge, or suburb, and it has a very distinguishable vegetation.
Concerning the city suburbs, the best definition would be, that that in those places the plant species or even humans can do almost anything. Also, it has often some kind of dream-like feature or let's say the appearance of subconsciousness. Those suburbs are funny, they are things together there, which shouldn't be, in strange and unexpected contexts. One short example how to recognize if you are in the true suburb or not: burn a tractor tire. If the police comes, you are not in the suburb, because you are still in focus of a public interest, and people care what happens around.
The last thing I will talk about is intentionality, or spontaneity. Most of the urban areas are directly created or formed by humans. It is planted, but very shortly after it is planted, the surrounding species come on the scene, and expand spontanelly previously purely artificial lawns or parks. It can never be a hundred percent intention or plan, it is never pure. Even all the artificial lawns, which are all around the supermarkets, they are full of very interesting, very exotic species, after one or two years, which were not planted for purpose.
And this is very important, maybe the most important of what I want to say here: if you are talking about the city vegetation, you have to realize, that human intention, or human psychology, or culture, is on the same level as sunlight, nutrient level, or percipitation. It is the part of the natural environment of these biotops. I offer a parallel - very similar features could be found in street art, billboards, or advertisements. They work according to the same principles as vegetation, only the object is different.
Here is a mall, where you can find various incriptions, about who is who and so on, but you can find here all the important processes, which are present in the suburb vegetation - overwriting, scratching, deleting, adding new inscriptions. It is completely open ended…
How to live in the city landscape
How to live in the city landscape if you have some level of vegetation knowledge? Where to sleep and eat? The suburban area or periphery is the best, because it is exotic, and majority of the city inhabitants avoid it. It is also rich in food resources, containing abandoned orchards or gardens.
One of the highly preffered biotops is the scary forest, dominated by Robinia pseudoacacia (tree, which comes from Northen America) and liane shrub Clematis vitalba. In such a multilayered vegetation you can hide very well, usually there are rocky or very steep slopes, and it is mostly inhabited. Almost all the species are foreign, and very interesting is taht the inhabitants are proud of it, they think that it is the real wilderness, and they sometimes also protect it by themselves.
On the other hand, natural biotops, which are also present in Prague, are almost empty. Why? Isn't it strange? For example in these rocks, there are some nice holes or small caves. These forests are dense enough to live in - so why are they empty? Why nobody lives there and everyone lives in the exotic zones? I will try to offer one possible conclusion: it could be, that the life on the city edge or in the periphery is more according to the lifestyle of people, who prefer this kind of lifestyle. You need to search for unstable resources, and so it is much easier to live in the unstable, changeable vegetation, rather that in natural ones, conservative and old biotops.
Search for a true periphery
Now about the two current projects, which I did. One was to walk around the city, nonstop, sleeping there, making the fire. My aim was, to try to distinguish, what is the true periphery, if we could at least very roughly paint some borders of it. We had a lable, a stick, which we placed on the columns with city lights and buildings.
You see, this the city centre, where you cannot do anything of what I was talking about, and this is the countryside, an area already controled by the villagers. But this zone here is more like a grey zone, where you can do almost everything. We made the fire, we slept there, we even sometimes tried to make objects, place stickers everywhere, talked to many locals… It was very interesting.
The second project was to inhabit shrubs for one weekend. We found out, especially shrubs in the suburbs are excellent places to do performances or even religious rituals. We also made a semi-religious ritual on the top of a coal mine heap.
What about the nature conservation
The last section is very short - why does nature conservation not say much about those places, or even ignores them? Here you can see two pictures, one from the eastern part of Prague periphery, and the other one from Krkonoše, which is the most famous and oldest national park in the Czech Republic. If you would compare their plant species diversity, they are quite similar. Why shouldn't we create a national park which would be in the city or in the city periphery? Why wouldn't we create a national park like this?
This is a detailed view of Kladno - I already mentioned its coal mines, which are these red spaces, which are quite interesting, even considering the plant species, insect species and so on. The diversity there is very high. I guess, theoretically it would be possible to create a national park without any problem, and we would have enough reasons to do so. Also, what we would do to keep it valuable, would be very interesting. It would be allowed to dump waste everywhere, because it is a part of it, it would be allowed to build shopping centres there, which would be a part of a care about the landscape. We would introduce new invasive species there for purpose, and we would also burn plastics or chemicals for purpose. We would abandon fields and orchards, and support homeless lifestyle.
Are we mature enough to do so? I am not sure.