The Earth After Us

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not even notice it. We give our own overlying air-ocean so little respect that we even describe anything that is full of air as being empty.”
Gabrielle Walker, An Ocean of Air
When thinking about the health of humans it is vital to think about the health of the elements around us which aid us in maintaining our energies. What for me began as a search into the health of the soil very soon turned into a quest – to see what we would leave behind as our “legacy”, a hundred years, two hundred years and also a million years from now. It has been the most challenging task I have undertaken - and even now, I am only slightly less confused.
‘The Earth After Us’by Jan Zalasiewicz was the book that I read and re-read in my attempt to understand what we were actually leaving behind. The opening scene of the movie Wall-E kept coming back to haunt me during my attempts at comprehension. Without stretching the imagination too much, we can envision a hot, barren world, where perhaps even a cockroach would not survive. A romantic would envision a world full of life, green trees and butterflies. I am certainly happier being a romantic!
No matter what stance we as humans take with respect to balancing ecology and development, we can never really disconnect and look at the earth as separate from us and our needs. For, we are in more ways than one, a part of the soil. The soil is alive – the many layers and layers that have been added over millennia and that will continue to be added long after we are gone. Past landscapes are preserved in the land under layers of rocks and sand and soil, as are the many fossilized remains of different kinds of creatures.
On a very elemental level, our bodies are made of the same components that made up the bodies of the dinosaurs more than million years ago, which have been left behind as fossils in the land. We are still made of the same elements that made up the very first single-celled organism and we are the very same elements that are found in petroleum. I believe it safe to say that the earth and by extension its parts, clay, sand, mud, rock and gravel are the most important structures for this support of life on earth. Zalasiewicz says this about mud, “Mud is indispensable to the functioning of the Earth’s life support systems, because of the importance of the numberless clay particles to the Earth’s geochemical cycles. It seems also to have been indispensable to the origin of life on this planet, for the reactions by which amino acids react together to form more complex organic structures proceed far more quickly in the presence of clay minerals.”
Mud, however, is more than clay. While clay is as complex as the minerals within it, it pales when compared with the richness of mud – with its dark and rich compost, which the bacteria constantly feed on. The number of bacteria is not few, there are millions of bacteria – of various types, each performing a different unique function, all of which are integral to the life-giving property of the soil.
It is therefore important to understand that mud is one of the world’s greatest carbon stores or as Zalasiewicz puts it “a planet-spanning communal tomb for the composted remains of many generations of living organisms”.
The complex hydrocarbons which form the shells / skin / stems of plants and animals above ground become buried, heated, and compressed, and then the complex hydrocarbons break down into simpler hydrocarbons which migrate underground, in some places accumulating as underground reservoirs of oil and gas (which we would then extract). Or, the liquid hydrocarbons may leak back to the surface, where they are absorbed and reborn into new generations of living organisms, thus keeping the circle of life going. These mud-derived carbon stores also act as a crucial control on climate, not least when occasionally exploited by energy-hungry civilizations.
While researching other arguments that did not hold a solely anthropocentric view of the earth and the soil, I found that there were very few in which the soil was mentioned or the land. It was mentioned when the questions of property arose – how we could acquire it, to whom it belonged, but never talked about the soil as an entity. Was it inevitable, the human blindness to the connection between soil and ourselves?

So, I asked myself once again “What will we leave behind?” Our mortal remains, no doubt, but what else? Dams that we build to control the flow of water, chemical fertilizers that we put into the soil, which accumulate over time and then acidify the soil? The layers of acidic soils, rich in minerals, but which contain little to support life – is that our legacy? Large, imposing structures to contain our growing need to shop? What happens to our oceans? It may be safe to assume that, even if we do not leave behind our fossils for study by aliens or our future generations,we would leave behind our elementary particles – and possibly hope that we are leaving behind a world, perhaps not an exceptional world, but one which will not be unstable and which still contains life, as we know it.
Zalasiewicz has this to say, “Take away the top predator dinosaurs, and the Jurassic ecosystems would have been a little different, to be sure, but no less functional. Take away humans, and the present world will function quite happily, as it did two hundred thousand years ago, before our species appeared. Take away worms and insects, and things would start seriously to fall apart. Take away bacteria and their yet more ancient cousins, the archaea, and the viruses too, and the world would die.”
An intense wish that humans were less anthropocentric and less self-centred, I realise, makes me ruminate along with Zalasiewicz on the compulsions of our civilisation and the legacy we would leave behind. Paradoxically, I also realise that this concern with legacy is very anthropocentric too…