Cities’ cryptobiotica: Part 1, the crust
No, cryptobiotica is not the newest
Viva cryptobiotica!
It’s a curious form of desert life that has a direct analog in housing and urban development, something very much on my mind since my recent trip to
Nancy and I first encountered cryptobiotica a dozen years ago when we were touring
Don’t bust the crust!
Cities and slums are economic ecosystems, and just as a biological ecosystem has its biota, so to do all the active entities – that is, the companies, professionals, and individuals who operate within the ecosystem – comprise its ecota [my ungainly term].
From a distance, cryptobiotica looks like nothing much:
Can you spot the most populous form of life in this picture?
Look more closely:
See anything alive in this picture?
That speckled mass, which gives the soil a held or dried-mud appearance, is a complex form of life. As described on the Web site of Capitol Reef National Park:
Cryptobiotic soil is found throughout the world. In arid regions, these living soil crusts are dominated by cyanobacteria, and also include soil lichens, mosses, green algae, microfungi and bacteria.
In other words, what appears from our vast height to be simply dried mud is actually a complex interdependent community of organisms that have eked an existence out of an inhospitable and apparently empty environment.
Sort of like the people who live in slums:
From outside the community, you can’t see its people
The farther away you get, the more a slum appears an undifferentiated groundcover. Slums, at least in the developing world, are usually very low-rise; single stories like Kibera, two stories in Dharavi. They’re so low to the ground because they are self-built and because slums are wealth-extraction machines. They crop up anywhere there is available land reasonably convenient to potential income:
Mumbai: slum community sandwiched between a four-star hotel and an airport warehouse loading dock.
Despite its visual insignificance, cryptobiotica is critical to the desert ecosystem:
These crusts play an important role in the ecosystems in which they occur. In the high deserts of the Colorado Plateau (which includes parts of
Like slums in the global south, which consume large sections of the world’s southern megacities. Just as slums are among the first forms of expanding urban habitation, cryptobiotica is a very early form of living ecosystem:
Cyanobacteria, previously called blue-green algae, are one of the oldest known life forms. It is thought that these organisms were among the first land colonizers of the Earth’s early land masses, and played an integral role in the formation and stabilization of early soils.
Slums do the same thing for growing cities in fusion countries: they create local enterprises:
They generate value:
The earliest cyanobacteria fossils found are called stromatolites, which date back more than 3.5 billion years. Extremely thick mats of these organisms converted the earth’s original carbon dioxide rich atmosphere into one rich in oxygen and capable of sustaining life.
We will forgive the aerobic-chauvinism of that last clause J.
Cyanobacteria occur as single cells or as filaments. The most common form found in Colorado Plateau soils are the filamentous type, which are usually surrounded by sticky, mucilaginous sheaths.
When moistened, cyanobacteria become active, moving through the soil and leaving a trail of sticky material behind. The sheath material sticks to surfaces such as rock or soil particles, forming an intricate web of fibers throughout the soil. In this way, loose soil particles are joined together, and an otherwise unstable surface becomes very resistant to both wind and water erosion.
Cryptobiotica soil, though comprised of the tiniest and most fragile of particles, creates this powerful network effect – it stabilizes the soil. Slums stabilize communities.
Business, enterprise, and activity in Dharavi
They create a nearby source of labor – most slum dwellers have a job of some kind – accessible and cheap. They fend for themselves, consuming very little community infrastructure and using every available space:
Loft bed added to a small 200-square-foot co-op high-rise flat, Dharavi
Up close, cryptobiotica are highly differentiated:
Of self-built structures:
So too are slums very tightly-knit communities.
Dharavi, Kibera, New York’s Lower East Side, or Boston’s pre-urban-renewal West End – they all have a vast network warning system – people’s eyes and ears and gossiping – that makes it impossible for outsiders to enter without being spotted long since.
You’re always noticeable
You are accepted only if you come with a guide.
Jockin knows where he’s going, and I’m just following him
They therefore offer havens for criminals and gangs such as Lucky Luciani’s Mafia and Haiti’s Cite Soleil drug kingpins, havens from which it is impossible to extract the thugs without harming the citizens.
Yet, like slums, cryptobiotic soil is easily destroyed. Back to Capitol Reef National Park:
Unfortunately, many human activities are incompatible with the presence and well-being of cryptobiotic soils. The fibers that confer such tensile strength to these crusts are no match for the compressional stress placed on them by footprints or machinery, especially when the crusts are dry and brittle.
Don’t bust the crust!
Tracks in continuous strips, such as those produced by vehicles or bicycles, are especially damaging, creating areas that are highly vulnerable to wind and water erosion. Rainfall carries away loose material, often creating channels along these tracks, especially when they occur on slopes.
Wind not only blows pieces of the pulverized crust away, thereby preventing reattachment to disturbed areas, but also disturbs the underlying loose soil, often covering nearby crusts. Since crustal organisms need light to photosynthesize, burial can mean death. When large sandy areas are impacted during dry periods, previously stable areas can become a series of shifting sand dunes in just a few years.
It takes only one ATV to mark the land for months and years
Impacted areas may never fully recover. Under the best circumstances, a thin veneer of cryptobiotic soil may return in five to seven years. Damage done to the sheath material, and the accompanying loss of soil nutrients, is repaired slowly during up to 50 years of cyanobacterial growth. Lichens and mosses may take even longer to recover.
It seems paradoxical that something so valuable over the decades, and so effective at micro scale, is so completely helpless against a moment’s catastrophe. Because of this, desert-lovers and cryptobiotica’s fans become passionate in its defense, as illustrated by this light but heartfelt plea from the Desert Foothills Land Trust:
Below the surface of the desert are other organisms, which decompose plant litter, making nutrients available for plants. Crust organisms contribute to this organic matter, as well as provide nitrogen to the soil. The Cyanobacteria also secrete compounds that stimulate plant growth. In this marvelous symbiotic relationship, Nature provides for the needs of the desert soil.
The loss of this kind of interdependent partnership in an ecosystem as fragile as the desert can spell life or death for plants and animals. Once the brittle crypto is compressed by vehicle tires or the feet of livestock or people, soil connections are broken, nutrients are lost, water runs off and soils are left open to damage. Even if the area is not disturbed again, it may take up to 250 years in a desert of low rainfall for recovery to occur.
An ecosystem built in splendid isolation crumbles if over-run by larger entities. What then is a heavy-footed human to do?
Staying home isn’t the only way to protect it. When you’re out driving, make sure you stay on established roads and trails. Hikers should use trails, too, or hike the washes and rocks. If you’re camping, stay in designated campgrounds or in areas where crusts don’t grow, like slickrock, beaches or groves of trees. Just stay off the little fellows. They may grow slowly, but they’re so full of life!
Rising up from the bacterial level, what does this mean for housing and urban development policy?
Don’t bust the crust!
[Continued tomorrow in Part 2.]
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