Re-Membering Our Relation to the Earth Soil for Ecologically Sound Cities

Historical cities offer insights relevant to current efforts to regenerate an ecologically healthy Earth. The following essay explores the bonds between three soil communities and their cities – Uruk, Athens, and Machu Picchu. These cities illustrate three different relationships to soil – as a Parasite on Soil, as a Disease of Soil, or as a Soil Maker. Based on this research, I urge us to re-member our relation to the Earth by making our habitats soil-generators.

The Seeding of Cities

Six thousand years ago ancient Uruk formed part of a network of settlements that for the first time made urban life possible. Located along the Euphrates River just north of the present-day Persian Gulf, Uruk was the chief cultural center of Sumer and its foremost religious center. In the sacred precinct of the fertility Goddess Ishtar stood her Ziggurat, representing the Cosmic Mountain rising out of the primal chaos at the moment of creation. Her Temple was never surpassed in Sumer in size and richness of architectural details. The terraces of the stepped altar regularly held the vegetable offerings from Uruk’s gardens and date groves, transforming the tiered Ziggurat into a series of “green roofs.”

The duty of the King of Uruk was to embellish and maintain his city. City walls dominated Sumerian urban architecture. Gateways displayed the city’s wealth, impressed visitors, and served as civic centers. To enhance these, King Gilgamesh defies an ancient sacred prohibition against felling cedars growing in the mountains north of the city. He and his companion, Enkidu, kill the protective forest monster. They clear-cut the cedars to construct a magnificent new gate in the city ramparts.

Gilgamesh’s actions anger the supreme Gods, who inflict flood, famine, and sorrow on the inhabitants of Uruk. The Gods also curse Enkidu, who embodies what is ‘wild and untamed’ in the human. He personifies what we recognize today as our alignment with natural systems. Enkidu dies a painful death. Horrified at the possibility of his own death, Gilgamesh seeks immortality. After fruitless wanderings, the King realizes that he can only achieve eternal life through the longevity of what he builds to sustain Uruk. At the end of the tale, he concentrates on maintaining the city walls, canals, gardens, and temple precincts.He concentrates on, what we would describe as sustaining the city’s relation to its ecology…to its place on the Earth.

Modern ecology interprets this nearly five-thousand-year-old tale for us. Clear cutting mountain forests destroys wild nature. It leads to increased water run-off and unexpected, often destructive flooding. Torrential inundations in turn drown crops in the surrounding low-lying lands, creating famine. Cities face the likelihood of demise when their food supply ends. Their citizens have dire choices: starving to death, subjugating foreign territories to supply them with food, being conquered by enemies, or abandoning their city.

Ecological design also illuminates the Gilgamesh legend. Human communities form life-dependent relations with the natural systems of their locality. Through trade, these essential bonds extend to the ecologies of far-distant lands. Sometimes, as in the case of Uruk, cities develop life-sustaining connections with remote territories whose natural bounty they violently seize. The Gilgamesh story, the oldest written record we have, warns us that in order for urban complexes to achieve longevity, city constructors cannot ignore these ecological connections. Instead, urban builders need to develop building practices that treat cities, their surrounding regions, the lands of their trading partners, and appropriated lands as one integrated organism.

History records that the rulers of Sumerian cities did learn to co-exist for an extraordinarily long time within the Euphrates-Tigris river system, just as the story of Gilgamesh suggests. They achieved an urban energetics giving their cities a longevity the Greek polis never obtained. Ultimately, the soils of Sumerian cities lost their viability but only after these settlements survived for nearly four millennia. Can our cities achieve a comparably long life?

Cities Integral to Soil Communities

Contrary to modern perceptions, human settlements are not separate from the natural systems they penetrate or from their neighboring countrysides. Instead, cities form vital relationships within their regional soil communities. British historian Edward Hyams describes the basic characteristics of soil communities and the position of cities within them in his extraordinary Soil & Civilization, a historical study of humanity’s place within the Earth’s planetary ecology.Hyams reminds us that soil is not a dead inert resource but an organism. The rock, humus, bacteria, atmosphere, water, fungi, and earthworms that comprise soil constitute a biological, organic, living community. Humans intrude into these communities by the way we create cities.

Hyams organizes the relational dynamics that cities form within existing soil communities into three energetics: Man as a Parasite on Soil, Man as a Disease of Soil, and Man as a Soil Maker.
In order for us to understand the functional place of green roofs, urban neighborhood gardens, and other similar soil-makers within today’s cities, we need to recognize the ongoing historical consequences of these three dynamics. They continue to constrain life on the Earth today. What follows is a brief description of three historical cities — Uruk, Athens, and Machu Picchu that illustrates the three major impacts of cities on their soil communities.

Cities as Parasites on Soil: Uruk

The success of Gilgamesh and succeeding rulers of Uruk is due in large part to modulating agricultural practices to the cyclical rhythms of the Euphrates-Tigris alluvial river system. Hyams characterizes this relationship between Uruk and the river system as that of a benign parasite to its host. In other words, the people of Uruk fed on the fertility of the river system, much as a few fleas live off a dog, without doing any damage to the canine. As Hyams indicates, the fruitful soils of the Euphrates-Tigris system “do not owe their nearly inexhaustible resources only to stored capital accumulated during countless years of silting, but to annual renewal by present and continuing silting.” Such soils “are capable of supporting a parasitic community for long periods, sometimes almost indefinitely.” For centuries, the parasitic relation of Sumerian cities to this resilient region did no apparent harm. The annual flooding of the rivers regularly regenerated the soil community. The Sumerians used the flooding as the basis of their irrigation-dependent agriculture whose fruits they offered to the goddess Ishtar.6

However, the waters of the river system, which were absolutely necessary to Sumerian irrigation, brought not only fertile silt but, after several thousand years of urban occupation, salt. The Sumerians could see the accumulating silt and took precautions against it clogging their city’s irrigation canals. They made dredging and cleaning of canals a top priority. The salt was a different story. It was invisible. Hundreds of years after Gilgamesh first challenged the forest god, the Sumerians gained control of new timberlands, which they exploited. This deforestation exposed expansive areas of salt-rich sedimentary rocks to severe erosion. Devastating floods and rains occurred, carrying salt downstream. The salt accumulated in irrigated farmlands. A serious salinity problem developed because of inadequate drainage that, otherwise, would have flushed the salts out of the topsoil. Non- reversible and increasingly destructive, the salt caused a progressive decline in crop yields, especially barley. After 2000 BC the Sumerian empire crumbled, in large part because of the decline of their food supply. Sumerian rulers subsequent to Gilgamesh had failed to heed the lessons of their own ancestors.

The same story can be told about the civilizations of the Nile, Indus, and Hwang-ho Rivers, which were born on the resilient soils of their river systems. These civilizations, like Sumer, transformed from being parasites on their soils to being diseases of them.

Cities as a Disease of Soil: Athens

“Disease is a failure in the balance by which species live together in community, whether in a relationship of mutual aid or one of parasite and host.” Hyams argues that even in the former case, there must be equilibrium. If there is “an adjusted balance between parasite and host, the former is fed, the latter not debilitated.” This was the situation in Uruk for about three thousand years after cities first came into existence and a thousand years after Gilgamesh reigned. Then, with the accumulation of salt in the soils, the balance was destroyed, the host soils collapsed and with them parasitic Uruk. Unlike the ancient Athenians, the peoples of Uruk were unable to devise ways to continue to flourish on their destroyed soils.

Improbable as it may seem, it is possible for a city that is a disease organism to create prosperity. The price can be high as such an existence is extremely precarious. Classical Athens is a case in point. Hyams argues that Athens was “forced, by the ancient ruin of her original soil communities, and the consequent spoiling of her top-soil, to conceive, build, man and master the art of a navy,” which made her master of Hellas.

The peoples inhabiting Classical Athens developed a city still admired today. They incorporated living vegetation, flowing water, topographically sited roadways, and passive solar buildings into a dynamic urban complex. Their gardens supplied fragrant flowers to purify the air and ward off disease. Water drained from house roofs to retaining basins to feed the gardens. They placed flower boxes against walls with vines trained up them, cooling the surrounding air. They also decorated their gardens with statuary of important people and their Gods.  When private green space was scarce, the Greeks devised rooftop gardens.

In addition, on the summit of Athens’s sacred Acropolis, whose name means top of the city, was an olive tree. Tradition tells us that Athena caused this olive tree to sprout when vying with Poseidon for control of the rocky, naturally fortified hill that came to overlook the Athenian agora. At the time of the contest for the Acropolis, which was long before the classical period, Athena was a Rock Goddess and Poseidon an Earth-Shaker or Lighting God of the sky who could bring rain.

To prove his ascendancy, Poseidon strikes his lightning–creating trident in the rock and a spring gushes forth, an extremely unusual event at the top of a hill. Athena magically evokes an olive tree. The judges of the contest decide in favor of Athena, but Poseidon in great wrath does not accept their judgment and floods the plain. In ways that are, unfortunately, not handed down to us, the gods bring about a union between warring Athena and Poseidon. As a result of this peace, Athens honors Poseidon as well as Athena, especially on the Acropolis, where the Erechtheion stands commemorating their generative powers. This mysterious building protects Athena’s olive tree as well as the trident marks of Poseidon. Although these indentations are inside the building, they communicate with the sky through a roof opening. Both the olive tree and the trident marks propitiate the gods in order to sustain the city through the precarious cultivation of the olive tree on the impoverished soils of Attica.

The olive and the fig tree as well as the grape vine belong to a family of plants, which can exploit poor soils. “Historical Attica,” as Hyams demonstrates, “inherited from prehistoric times one of the poorest and thinnest soils in Hellas.” But classical Athens refused to play the inconsequential role necessitated by the thin and stony soils its ancestors created. Its inhabitants learned to exploit the subsoil as well as create a contrived soil community in which one of its members was a foreign market. Hyams demonstrates that the olive, in particular, became “unquestionably the spring of Athenian wealth, power, and civilization.”

But to feed 300,000 inhabitants in the time of Pericles, Athens needed more than locally grown olives, grapes, and figs, and locally produced oil and wine. The Athenians traded these commodities for wheat to make bread. Out of necessity they developed ceramics to contain the wine and oil and shipbuilding industries to support their exporting enterprises. The rising commercial importance of Athens in turn necessitated the creation of a fighting navy so Athens could defend herself. Thus, the “challenge of her wretched top-soil made Athens a great manufacturing, mercantile, and naval power.”  But as Hyams warns,

“It is not safe to forget that trading for food which your land will not afford directly, is a precarious and vulnerable expedient. … The mortal weakness of having a member of your artificial soil community outside your control generates fear in proportion to what you have to lose. Athens had an empire to lose, an empire largely created by her fear-inspired arrogance … (Nothing) could save the city from the trap which the poverty of Athenian soil had set… the disgrace and decline of the power, the name and culture of Athens.”

Just as classical Athens, modern cities are diseases on their soil communities. The Climate Emergency and Covid-19 Pandemic are showing us what happens when cities and nations can no longer supply fundamental necessities, such as food. Modern cities cannot feed themselves within their local soil communities. A fundamental shift in perception is necessary before we can address this and other problems of the sustainability of all species within their soil communities. French archaeologists Sander E. van der Leeuw and Chr.Aschan-Leygonie contend that

“most, if not all, of the ‘environmental’ problems we encounter are exacerbated by the ‘nature-culture’ opposition in our minds. Separating ourselves from what we consider to be “nature”, we have tended to favour human intervention in the natural domain as the way to ‘solve’ … ‘environmental’ problems. … A growing awareness of this issue has triggered a shift in the debate on environmental matters. … the general tenor of the shift in perspective can be summarized by pointing out that the role of human beings in socio-environmental relations has gone from re-active, via pro-active, to inter-active. The first two perspectives are anthropocentric: either we make exceptions of ourselves by taking no responsibility, or we do so by taking all the responsibility. In the last perspective, humans become “just another unique species”…, and take part of the responsibility – which is much more difficult, as it necessitates determining, in every instance again, where the limits of our responsibility as human beings lie.”

Can our role in socio-ecological relations become co-creative as members of our local soil communities? Can we learn what the latter-day people of Uruk and the citizens of historical Athens did not? Can we become organic soil makers? The ancient Incan city of Machu Picchu with its graceful gardens and agricultural terraces atop an 8,000-foot high mountain demonstrates how a human settlement in the most unlikely place can be a soil maker and an inspiration for co-creating soil-creating efforts.

Cities as Soil Makers: Machu Picchu

“The true monuments of Inca civilization exist in a context too humble for ready transmission to modern sensibilities. The Incas were arguably the world’s finest stonemasons, but they did not lavish their skill on ornate temple complexes.” As ethno-astronomer William Sullivan points out in The Secret of the Incas: Myth, Astronomy, and the War Against Time, “Instead they built soil.” Soil is sacred to the people living in the Andes Mountains in South America. The Earth itself, the Pachamamma, is “the Mother-Goddess of all things.” By the end of the 11th century A.D., the Incas had organized the many local peoples of this rugged land into an Empire. Known as Tahua-ntin-suyu or The Four Combined Provinces, it reached at its greatest extent 2700 miles along the present Pacific coast.

The strength of the Inca Empire rooted in a soil community blending humanly made-organic and native soils. As Hyams documents, successful soil-making entails a strict social discipline. For the Incas this meant becoming “the most perfectly symmetrical and stable political units” humanity has ever achieved. Despite its complex organization, the Incas retained the most important of their peoples’ ancient tribal customs — the communal ownership and working of land. From 1400-1532 A.D., this collectively-held, humanly-made land produced food surpluses used to supply its armies, feed its orphans and widows, eliminate poverty, and thwart famine for the first and perhaps only time in history.

How was such an achievement possible? Quite simply, the Andean people were not content as parasites on the sparse existing alluvial soils or to become a disease of their soils. “In their narrow, mountainous tract, they lacked not merely fertile soil but level surfaces of any soil at all. It was necessary to expand on to the mountainsides. …To do this they must check the erosion of the slopes and build surfaces level enough to be worked even without the plough.” They must find ways to cultivate the rainless coastal strips of apparent desert as well as the inland desert areas. In order to expand over soils not receiving floodwaters, they must discover the principles of soil regeneration. By carefully regulated and controlled use of manures from fish, by terracing, pit digging and irrigation, the Incas converted their poor natural soil communities into rich, stable, humanly made, organic ones. In short, in contrast to the Athenians and the inhabitants of modern cities, the Incas were able, without recourse to trade, to feed their fast-growing population by becoming organic soil-makers.

The city of Machu Picchu with its one thousand inhabitants provides us with a fitting example of soil-making relevant to contemporary soil-making efforts.   Urban ecologists advocate ameliorating modern impacts on the biosphere by constructing cities integral to their natural systems. Some of the functions that the builders of Machu Picchu constructed their sacred city to perform green roofs accomplish today – providing and controlling water flow, making available much-needed space for local agriculture, medicinal herbs, and decorative gardens that buoy up human health and well-being.

Until recently, no one really understood what an extraordinary civil engineering feat Machu Picchu represents. Denver-based hydrologic engineer Kenneth Wright and his team discovered that this magical city in the clouds is nothing less than an astonishing interlocking preplanned system that integrates hydrology, hydraulics, drainage, foundation engineering, masonry building technologies, soil making, and agriculture. After twenty years of requesting permission to investigate Machu Picchu, Wright began extensive on-the-ground research in 1994. To his amazement, Wright realized that this complex of massive stone buildings and agricultural terraces was conceived and built as a single entirety.

Reflecting on Wright’s descriptions of what he found, I thought of the comparable size and intricacy of the huge multi-functional structures being proposed today. Cities all over the world compete to build the tallest, the biggest edifices. None of them that I am aware of are designed as a single ecologically-functioning entity rooted in the ecology of the place where they are being built. The continuing functioning of the integrated natural and urban systems at Machu Picchu attest to their sophisticated knowledge of city building, a knowledge that could nourish our own much-needed regenerative processes.

Water is key to understanding Incan civil engineering, just as water is critical to the regeneration of the soil communities in today’s urban-natural dynamics. Where did Machu Picchu get its water? How did the Incas bring the water to the city, distribute, drain and carry it away from their city? Even though U.S. explorer Hiram Bingham had uncovered the lost city of Machu Picchu in the early 1900’s, no one had documented the city from this point of view until Wright began his work.

Farmers living near Machu Picchu led Wright to the location of the water source on a steep mountain slope north of the city. He realized that the path of the water determined the entire urban layout, including the site of the emperor’s residence and the agricultural terraces. The present condition of the system surprised Wright. “The spring works was still intact and still working. It was still yielding a water supply after all these (four and a half) centuries of abandonment.” The Inca constructors “built for permanency.

The Flowering of Cities

Imagine the Possibilities! Entire urban assemblages of buildings, walkways, streets, plazas, parks, water systems, sewage, waste disposal and more. All integrated into an urban energetics that gathers the movement of water, air, energy, and materials into and out of the entire city as one multi-faceted dynamic that is part of its regional ecology. No longer either parasites or diseases on soils, these soil-making cities could create a new, regenerative era in city building.

We are experiencing the human-amplified Climate Emergency and the Covid-19 Pandemic killing millions of species of plants and many animals in addition to ourselves. Extensive soil communities in our cities could create a planetary network helping to rejuvenate the Earth and its many life forms. But, as Hyams reminds us, we must design the layout of the our cities in ways that remind us of our place in the Earth Community:

“Everything touched by and serving living beings must either be adapted to the fact that the user’s life is organic, or must corrupt the user by withdrawing his attention from this fact.”

Climate Emergency, Pandemic, Racial Injustice – all point to humanity’s fatal error. We are notthesuperior species on the Earth. We are Earth Sprouts. Can we stop the violence arising from our arrogance? Can we support the resilience of the Earth – Our home?