Soil
(⚠️🤖 This post translation from the original text in Spanish was assisted using Llama 3 running locally with Ollama running on a solar powered laptop)
Hey there!
Mafe and Yema here, excited to share our latest monthly post with you, inspired by the project’s teachings. Last year, we started exploring the concept of the “Four Elements” based on ancient Greek philosophy: water, earth, fire, and air. We began with water, then took a detour to explore other topics, but now it’s time to get back on track and continue our journey through the elements, starting with the earth this year.
There’s something that makes soil less conspicuous than other resources. It doesn’t form part of the big conversations about climate change, biodiversity loss, or planetary boundaries. Yet, virtually all food production on the planet depends on soil 1. We have several theories as to why there is general indifference towards soil, but the one that resonates with us most is that it’s associated with processes of death and decay, you “get dirty” when you touch the earth. Soil is what lies beneath our feet, literally something we trample upon and an aspect that has no value in our imagination. In a way, it’s a relationship similar to our attitude towards waste, where indifference to this valuable resource is just as dangerous as indifference to the triple crisis (loss of biodiversity, pollution and climate change). The fact is that all these major crises are interconnected, and you can’t address one without addressing the others. That’s why we want to share our experience with soil, what we see when we dig and what grows on it, its texture, colors, and scents.
Everything that goes up comes down… and goes back up
In general, we’ve been taught to gaze up at the skies and aspire to ascension. We spend our lives looking up at the stars, seeking transcendence in the heavens above. But in this pursuit of elevation, we often forget that solid foundations are needed for growth. If we take a closer look down below, we might just discover another universe right beneath our feet, one that’s much more within our grasp.
If we’re in the city, there will be a lot of pavement and concrete, but also the occasional park covered with grass, maybe some flowers or herbs, and one or two trees. If we’re lucky enough to have a lazy gardener, we’ll see leaf litter around the trees and, if we’re even luckier, a mushroom cap poking out. Eventually, the tree that slowly grew over 100 years will fall, just like the birds that nested in it and the squirrel that climbed its trunk and fed on its seeds. There’s something key in this process of ascent and descent: soil isn’t just a support but one of the great catalysts in the cycle of life.
This process is more evident in a native forest undergoing restoration. If we really observe, we’ll see grass, seeds germinating, saplings, freshly fallen branches, lichens, bromeliads or orchids knocked down by the rain, wildflowers, decomposing leaf litter, fruits, acorns, burrows, bees, ants, mushrooms, grasshoppers, field mice, bird broods, animal droppings, and many other elements. It’s as if life is “down there” were in perpetual revolution.
All of them contribute in one way or another to recycling and enriching the organic and inorganic material that “falls” to the floor by grinding it, decomposing it, and converting it into compounds that can be used by plants and other organisms, thus closing the cycle. In this frenzy, it’s difficult to distinguish where an organism’s task ends and the next one begins; not to mention the rain and wind that erode rocks, transporting minerals and other nutrients that will mingle with this rich soil to create a unique environment. It’s no wonder that soil is considered one of the most biodiverse ecosystems on the planet 2, containing up to 25% of it 3. We could ask ourselves then if when talking about diversity, shouldn’t we include in our equation the humble and underappreciated earth.
A renewable resource
This dynamic might lead one to believe that, given that it’s a constantly renewing resource, we shouldn’t worry too much about the accelerated erosion caused by humans and the subsequent loss of soil. After all, it’s just a matter of planting some trees, setting up an irrigation system, adding compost, and in a few months or years, all that diversity will come back. Reality isn’t so simple. According to FAO studies4, the topsoil (the upper layer of soil) is formed at a glacial pace of 0.25 to 1.5 mm per year. As some scientists say, it’s almost a non-renewable resource, and once that superficial cover has been lost, it may take decades, a lot of money, and hard work to restore it. We might then fall into the same trap as direct carbon capture technologies, which promise to gobble up atmospheric carbon at an astronomical energy cost.
At Yátaro we were lucky that despite being used as a pasture for dairy cattle, the soil wasn’t as compacted. Additionally, since several decades ago there was no agricultural production using agrochemicals, it meant we didn’t have to undertake a laborious soil restoration project. Sadly, some friends haven’t been so lucky and have had to embark on a task that can take years (check out the arduous work done by Vamos Pal Campo’s folks) to recover their land and be able to plant an orchard.
Aquí queremos aclarar que no somos anti-agricultura, ni anti-ganadería: también vamos al mercado y compramos productos de la tierra. Por eso mismo nos preocupa llegar a un punto de no retorno en el cual no haya tierra fértil para alimentarnos. Es entonces crítico estar abiertos a otras formas de producir nuestros alimentos porque la solución no es fácil ni obvia, pero resignarse al problema tampoco es opción. Para los que están en Bogotá La Canasta es una de varias opciones de consumo alternativo.
Here we want to clarify that we’re not anti-agriculture or anti-cattle farming: we also go to the market and buy products from the land. But exactly because of that it concerns us that we may reach a point of no return where there’s no fertile soil left to feed ourselves. It’s then crucial to be open to other ways of producing our food because the solution isn’t easy or obvious, but resigning ourselves to the problem isn’t an option either. For those in Bogotá, La Canasta is one of several alternative consumption options and we’re sure that every major city in Colombia and the world has similar initiatives.
Geosmin
When we arrived at the reserve a couple of years ago, we faced a small challenge: what to do with organic waste? We were in a remote location where the garbage truck didn’t pass and we didn’t want to store it for several days before taking it to another place where we could properly dispose of it. We thought about using earthworms or traditional composting, but the changes in humidity and temperature between summer and winter made us need complex infrastructure and logistics. After investigating a bit, we found a solution that simplified our lives and didn’t require extra effort or infrastructure: a compost bin. We weren’t sure if it would work and even today our compost isn’t the most beautiful. We still have to work on timing, carbon-to-nitrogen ratios, and coarseness of the material that we use, but what we’ve managed to do is to successfully use the compost to fertilize the edible forest. When we started using the bin, we didn’t know how to determine if the process was working. We had read that temperature is a way to measure organic activity in the composter, but with changing weather it was hard to tell if it was working. Something nobody or almost nobody explains is that as organic matter “degrades” in the compost bin, its smell tends to be very similar to that of black earth. That’s how we knew the process was working: our nose told us that if it smelled like damp soil, things were going well.
This characteristic smell is called geosmin and is produced by certain bacteria, cyanobacteria, and fungi that are found in the soil and help with the recycling process of plant material. Something interesting about geosmin is that from fruit flies to humans, passing through camels, we all detect its “scent”5. This says a lot about the common bond we share between animals, not just plants, with the earth.
There’s something about soil that we need to make conscious: it’s not just the basis of our food, but where we live for most of our lives. In a few words, it’s the sustenance of our species.
As always, we’d love to know what you think: What would you like us to share in our next posts?
Hugs from the mountain and thanks for reading.
1 Kopittke, P. M. et al. Soil and the intensification of agriculture for global food security. Environ. Int. https://doi.org/10.1016/j.envint.2019.105078 (2019).
2 Unearthing the Soil Microbiome, Climate Change, Carbon Storage Nexus, https://asm.org/Articles/2021/May/Unearthing-the-Soil-Microbiome,-Climate-Change,-Ca
3 FAO et al. State of knowledge of soil biodiversity - Status, challenges and potentialities (2020).
4 Agro-Ecological Land Resources Assessment for Agricultural Development Planning. https://www.fao.org/4/t0733e/T0733E06.htm
5 https://es.wikipedia.org/wiki/Geosmina