Something tells me that most of you live in cities. How much do you know about them?

Now it is fashionable to talk about cities as living, evolving systems. This phenomenon began with the creation of the theory of self-organization of systems - synergetics - at the end of the 20th century. In her terms, the city is called "an open dynamic dissipative system", and one can build its model - "an object illustrating the dependence of form transformations on changing content" and describe "internal structural transformations, taking into account the possibility of an indefinite behavior of the system in time". All these graphs, tables and algorithms in an unspoiled person cause a normal defensive reaction of stupor. But not everything is so hopeless.

Under the cut there will be several bionic analogies that will allow you to look at the city from the outside and understand how it lives, how it develops, moves, gets sick and dies. So let's not waste time and get to the dismemberment.

In addition to mathematical, cognitive and formal models, there is also such a technique as an analogy, which has been used by man for many thousands of years and has proven itself well for simplifying understanding. Of course, making forecasts based on analogies is a disastrous business, but you can track the dynamics of the process: in every self-respecting system there are energy sources, ways of its transmission, points of use, growth vectors, and so on. The first attempts to apply the concept of bionics to urban planning date back to the 1930s, but they did not receive much development then, since there is no complete analogy of the city in wildlife (if it were found, it would be really strange). On the other hand, certain aspects of the “physiology” of the city have good correspondences. As much as I'd like to flatter the city, it basically behaves like a single-celled, lichen, colony of micro-organisms, or multicellular animal a little more complex than a sponge.

Architects distinguish many structures and subsystems in the structure of the city, each with its own name, many of which you may have met, like a transport system or a housing stock structure, while others you probably have not heard of, for example, a visual frame or a mental map. However, each element has its own clear functional purpose.

Skeleton

The very first thing you will come across when dissecting any settlement is its frame of axes-bones and nodes-joints. This is what gives form and directs development from the first days. Each individual cell has a frame, without it no processes can really be organized, so it is logical that both the metropolis and the most seedy village have it. Firstly, these are the main roads oriented to neighboring settlements. The city will want to stretch along them, and they will become the most stable lines on the plan, unchanged for centuries. Secondly, the skeleton includes obstacles: rivers, lakes, swamps, ravines and other geographical inconveniences that stop growth, squeezing the growing settlement like an outer shell. On the other hand, it was precisely such elements that often served as a defense for the citadels of medieval cities, and governing bodies gravitated towards them, so that some forms of relief can be called with a clear conscience the bones of the skull that hide the brain.

If a set of these parameters is already set, it is possible to predict the shape of the settlement in the future and how the network of smaller roads will develop, on which meat and entrails will grow. And if in the old cities everything worked by itself, then in Soviet times, when drawing up the general plans for new cities, the authors of the projects had to move their convolutions, combining (not always successfully) natural tendencies and the dictates of the party leadership.

What can you learn from this:

• The skeleton must be connected, new elements always join the old - if the city has problems with the connectivity of the road network, it will have problems with growth and with economic stability.
• The surrounding tissues at the joints of the joints have a complex and peculiar structure - street intersections attract trade, services, pedestrian network nodes, and vice versa “squeeze out” ordinary housing.
• An organism with a large number of “shell” elements either stops developing and growing, or is forced to destroy them - the key point in the development of a huge number of cities is to cross the river or drain the swamp, and if there are not enough resources for such a mega-project, the city can to be in stagnation for centuries, without increasing the territory and without increasing its economic importance;
• It is advantageous to lay the main blood vessels along the elements of the skeleton, since they are the most unchanged in time - roads and engineering communications gravitate towards each other for a reason, but more on that below.

Stuffing

Meat, it is also muscles and fat, and in cells, the cytoplasm is such a thing that surrounds the bones, forming the bulk of the body of a living being, accumulates and releases resources, provides movement and determines overall viability. For the city, of course, this is what architects call “urban fabric”, “filling” and other boring words: ordinary quarters, mostly residential.

As any creature builds up mass at every opportunity, so the city, with better supplies, begins to attract more people and build new sleeping areas, even if it cannot always provide these “internal migrants” with a normal standard of living and work. Low-rise areas are pleasant, but ineffective - this is fat, poorly penetrated by blood vessels and containing few cells useful to the body.

What can you learn from this:

• Muscles tend to be evenly spaced along the skeleton; thicker bone has a thicker layer of muscle. Residential areas will behave in the same way: near larger highways, the population density will be higher than near secondary ones.
• If the muscle is poorly supplied with blood, it dies off - areas with poor transport accessibility grow more slowly than others, housing in them becomes cheaper and not repaired, the population is gradually marginalized.
• If pieces of fat are squeezed from all sides by muscles (and low-rise old districts are high-rise), we can get “inflammation”, which will either lead to the disappearance of this type of development (then consider that we just temporarily reserved this volume), or to the transformation of the entire surrounding area into a “gangster” or to the transformation of the building into an elite, puppeted and fenced quarter - this is already a kind of “cyst”.
• If the body becomes fat on the surface (and the city is on the perimeter), it becomes difficult for it to carry so much inefficient tissue, it suffocates, blood vessels dilate and become clogged with blood clots, and internal organs experience a disproportionate load and fail. All the charms of suburbanization as they are: traffic jams, the inability to easily get to work and infrastructure, the load on the central infrastructure is many times greater than calculated, the withering away of social ties, and so on.

This city is developing in a spiral. It is immediately clear that it arose naturally, and was not built from scratch.

Circulatory system

Each process requires resources. For the city, these are people, cargo, water, energy, information and time. The circulatory system redistributes resources between organs. The transport system of the city deals with people and goods, engineering networks deal with energy and information. It is not always profitable to transport energy over long distances, so raw materials for its production can be transported, as glucose is delivered to mitochondria.

Engineering networks of all kinds are usually grouped with transport arteries for several reasons: firstly, they are brought to new areas at the same time and it is unprofitable to work in two places at once; secondly, as already mentioned, this is an island of stability, “buried and forgotten”, and tomorrow a skyscraper will not grow here; thirdly, there is an opportunity to save on the “vessel shell” by building common protective and engineering structures-collectors; fourthly, it is important to save space on indents, because there are zones and elements that can coexist, while others are harmful to each other.

What can you learn from this:

• Wide vessels carry blood over long distances, so there is less resistance, and on the periphery they branch out and the speed decreases.
• Muscles are supplied with blood through a network of small vessels, the uniformity of supply is important here, and large ones go to vital organs.
• Blood not only brings resources, but also removes spent ones, so sewage systems obey the same laws.
• If the basic communications have already been brought to the area, it begins to grow very quickly and efficiently. The growth of the city in a spiral is widespread: each next district is adjacent to the previous one and to the old buildings, large-scale work is usually not carried out in two places at the same time (in large modern cities there may be several such “growth points”, for example, by the number of districts, then the spiral is obtained not as noticeable).

Nervous system

The nervous system consists of nodes that process data and send signals and signal transmission pathways. Since our information went under the “resources” column, it means that this is not about the Internet. It's about management. And I have some sad news for you: cities are very primitive organisms, and they are badly managed. General plans are not being implemented, the real situation does not correspond to the administration's data, control signals often do not reach or work in a bizarre way, the reaction to any changes is always late.

But it’s also bad to live in changing conditions without management at all, so the city is usually divided into areas subject to local “ganglia”, which have a chance to have time to correct something and prevent the situation from reaching a dead end (the sacral “rear” brain of large dinosaurs confirms that it works). At the same time, if the administrative division was made without taking into account the specifics of the skeleton, muscle tissue and circulatory system, the body will act and develop in a non-optimal way. An example from life: the river divides the city into northern and southern halves, and the administrative districts into eastern and western parts. As a result, we have a division into quarters and the constant need to coordinate actions between the two administrations.

By the way, the Russian Federation is now going through a difficult period of changing the system of rigidly drawn “general plans”, which, in principle, did not work well, to a system of flexible strategies - “master plans”, with which so far few people even understand what to do. Therefore, my crystal ball predicts: do not even expect stable and logical urban development in the coming years.

What can you learn from this:

• Large cities do not balance the needs and prospects of their districts well. Funds are distributed both unevenly and irrationally. Presumably, the master plan will be able to deal with the problem, “but this is not certain” (c).
• Cities with more than 400 thousand inhabitants were recognized as self-governing systems back in Soviet times, so if you live in one of these, just don't look for logic on scales of more than a few kilometers. To implement a project that affects several districts at once, you need huge funds and a powerful administrative resource, and still someone will screw up, and the last kilometer of the ring road will be built for ten years ..
• In zones at the junction of districts, all sorts of incomprehensible game is often going on, they can even “substitute” each other, for example, by building a large building where a road that is important for another district could pass.

This city is well divided in half. The main thing is not to confuse how.

Digestive system

What happens to the resources coming into the city? They are either processed beyond recognition or finely crushed and distributed throughout the body with the help of the circulatory system. Just as fatty acids are converted in the liver to acetoacetic acid, most of which is used outside the liver, in various tissues and organs, so food and goods from storage areas are transported throughout the city. In industrial complexes, a variety of transformations take place, but their results are invariably the same: they are used to maintain the viability of the organism. Not everything directly goes to residents, there are both construction and transport industries aimed at growth (they can be compared with protein metabolism, and everyday goods with carbohydrate).

What can you learn from this:

• The digestive system is very closely connected with the excretory system and cannot function without it.
• Industrial zones need a supply of a large amount of resources (including people) and energy. Large arteries are expensive, so it is rational to use them for several similar processes. This leads to clustering according to the transport principle.
• Recycling of resources is often a step-by-step process, and the metabolite of one process is the starting material for another. This creates a "combine" clustering of successive stages.
• Large organs are connected with the body only at a few points, so for other tissues they play the role of barriers in the blood supply. This dictates the specificity of the location of industrial zones in the city. Cities that have outgrown their scheme need an emergency “cavernous operation” – the removal of industrial zones and the re-profiling of territories. By the way, many unique projects are associated with this in various cities of the world. For example, tight-fisted Britons staged a global reconstruction of the port and warehouse areas of London under the banner of preparation for the Olympics.

Excretory system

Without sewerage, there is no civilization, everyone knows that. In the body, blood is filtered from harmful substances by two organs: the liver and kidneys (the number of kidneys in organisms is different, so we will not delve into it). The kidneys remove what they can unchanged, and the liver converts the waste (sometimes into more dangerous metabolites). The intestines just take out unused resources, in our analogy, this is the removal of solid waste to landfills. The sewer system acts as a kidney (unless you have methane tanks that convert waste into energy). Waste processing plants, waste incineration plants and methane tanks perform the function of the liver.

What can you learn from this:

• Recycled waste can be more toxic than unprocessed waste, like methyl alcohol, which is metabolized by alcohol dehydrogenase in the liver to formaldehyde and formic acid. Hello, hello, incinerators, I see you.
• Waste can be a valuable resource. After intensive physical work, lactate, formed during anaerobic glycolysis in skeletal muscles, returns to the liver and is converted there into glucose, which again enters the muscles. If a city starts recycling its garbage and using the resulting products within itself, this is very cool both in terms of saving raw materials and in terms of logistics.
• Poorly organized recycling and storage of waste can poison the life of entire areas, remember the protests against landfills, “aromas” from filtration fields and incinerators, “battles” between residents and management companies over the removal of solid household waste. Naturally, housing in areas with such problems will depreciate, become rented, attract low-income, poorly educated and not very decent citizens, who will further worsen its image. Ghettoization is a positive feedback process, and completely different factors can trigger it.

In fact, this article is far from exhaustive, and even more so does not claim to be scientifically accurate. About the growth of cities, their movement, diseases, digestion of space and other "physiological processes" I will tell some other time, so as not to lump everything together. If you have something to add, or have questions, I look forward to your comments. Thanks for reading, I hope it wasn't boring.

Source: habr.com