10/31/2022
"Beneath our feet is an ecosystem so astonishing that it tests the limits of our imagination. It’s as diverse as a rainforest or a coral reef. We depend on it for 99% of our food, yet we scarcely know it. Soil.
Plants release into the soil between 11% and 40% of all the sugars they make through photosynthesis. They don’t leak them accidentally. They deliberately pump them into the ground. Stranger still, before releasing them, they turn some of these sugars into compounds of tremendous complexity.
Making such chemicals requires energy and resources, so this looks like pouring money down the drain. Why do they do it? The answer unlocks the gate to a secret garden.
These complex chemicals are pumped into the zone immediately surrounding the plant’s roots, which is called the rhizosphere. They are released to create and manage its relationships.
The bacteria responding to its call consume the sugars the plant feeds them and proliferate to form some of the densest microbial communities on Earth. There can be a billion bacteria in a single gram of the rhizosphere; they unlock the nutrients on which the plant depends and produce growth hormones and other chemicals that help it grow.
Soil might not be as beautiful to the eye as a rainforest or a coral reef, but once you begin to understand it, it is as beautiful to the mind. Upon this understanding our survival might hang.
A non-profit organisation in Salina, Kansas, called the Land Institute. It’s seeking to develop perennial grain crops to replace the annual plants from which we obtain the great majority of our food. Annuals are plants that die after a single growing season. Perennials survive from one year to the next.
Large areas dominated by annuals are rare in nature. They tend to colonise ground in the wake of catastrophe: a fire, flood, landslide or volcanic eruption that exposes bare rock or soil. In cultivating annuals, we must keep the land in a catastrophic state. If we grew perennial grain crops, we would be less reliant on smashing living systems apart to produce our food.
For 40 years, the Land Institute has been scouring the world for perennial species that could replace the annuals we grow. Already, working with Fengyi Hu and his team at Yunnan University in China, it has developed a perennial rice with yields that match, and in some cases exceed, those of modern annual breeds. Farmers are queueing up for seed. While annual rice farming can cause devastating erosion, the long roots of the perennial varieties bind and protect the soil. Some perennial rice crops have now been harvested six times without replanting.
Perennials are their own green manures. The longer they grow, the stronger their relationships with microbes that fix nitrogen from the air and release other minerals. One estimate suggests that perennial systems hold five times as much of the water that falls on the ground as annual crops do.
The Land Institute is developing promising lines of perennial wheat, oil crops and other grains. The deep roots and tough structures of perennial plants could help them to withstand climate chaos. The perennial sunflowers the institute is breeding have sailed through two severe droughts, one of which entirely destroyed the annual sunflowers grown alongside them.
While no solution is a panacea, I believe that some of the components of a new global food system – one that is more resilient, more distributed, more diverse and more sustainable – are falling into place. If it happens, it will be built on our new knowledge of the most neglected of major ecosystems: the soil. It could resolve the greatest of all dilemmas: how to feed ourselves without destroying the living systems on which we depend. The future is underground."
~George Monbiot
Regenesis: Feeding the World Without Devouring the Planet by George Monbiot is published by Penguin Books
This article: https://landinstitute.org/media-coverage/secret-world-beneath-our-feet-is-mind-blowing-and-the-key-to-the-planets-future/
