Small lesson in agronomy (1/2)

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Protect soil to preserve biodiversity

An intervention by those called “the doctors of the earth”, or in any case, one of the two: Claude Bourguignon will tell us about his journey and the soil.

Claude Bourguignon: First, I would like to thank the organizers of the 2nd international session on biodiversity, who invited us. I would like to excuse Lydia: we have been a little overloaded these days, we have taken the plane 15 times in a month, we are a bit on the kneecaps; so she apologizes and asked me to represent her.

I will quickly talk about my journey, I have a somewhat special journey since I did not want to do agronomy at all. At the age of 14, I founded the Parisian ornithological group with friends from the Lycée Montaigne. I worked with WWF, we started to create reserves and I wanted to work in ecology. So I did a master’s degree in physiology and zoology at the University of Paris.

It was while working on Himalayan tiger counts that I saw people starving for the first time in my life. I had never seen that, I was a post-war kid, I did not know what famine was and I said to myself: we cannot protect tigers if there are people who starve.

So I came back from India, I introduced myself to Agro and I was received I don’t know how. Blow of pot what. It is true that I had publications since the age of 14, that is perhaps what allowed me to return. And there I discovered a crazy world! We were taught to give meat to cows to increase milk production, we were taught the art of crowding poor animals in hellish conditions, nitrogen overloads and everything … I said but they are crazy to tie these guys.

So I decided in the third year to go into soil microbiology, to take up the soil at the base.

At the time there was still a chair in soil microbiology at the Agro. By the time I got there, Monod, the Nobel Prize winner had just become director of the Pasteur Institute and the first thing he did when he got there was to remove the soil microbiology lab, saying that soil microbiology was useless.

The 3 researchers Kaiser, Tardieu and Pochon no longer had a laboratory. They were screwed up at the door and received in the Agro soil microbiology laboratory. So I ended up with 3 teachers near to retire and I rediscovered common sense: men who taught me that it was the mycorrhizae that gave phosphorus to plants, that it was the sulfobacteria that gave sulfur etc. I was alone with them and I had a private lesson during my third year … and moreover I finished the first in my specialty, which was still practical.

Then, leaving Agro, there was only one laboratory in soil microbiology, it was Dijon. This is where I met Lydia. She was working on food quality, and I was working on soil quality, and we met like that. As INRA, at the time, did not want to hear about organic farming, and that with Philippe Desbrosses we met regularly on the sly, because it was strictly prohibited by INRA to work on biology , so I started to look like a bad head at Agro. In addition I founded a college of biodynamic agriculture in Malleval with scientific friends so INRA wanted us to stop this college by saying that it was scandalous, that I stained the image of INRA, therefore I really passed for someone not nice.

So with Lydia we decided to leave the institute. We founded our laboratory in 1989: a microbiological soil analysis laboratory. Since 89 we have analyzed over 12,000 soils around the world, in just about every ecology on the planet, so without boasting I can start telling you how it works.

So I’m going to recall how a soil works in our regions. France, before we cultivated it, was 90% covered with forests. How does a floor work? A soil works for thousands of years without being degraded and as soon as Man steps on it, it breaks everything. Why does man break soils when nature knows how to grow them for thousands of years?

To give you an idea, the oldest biological model that we know of is the Borneo forest, a forest which is 150 million years old, which receives between 3m and 9m of water per year and which continues to grow tallest trees in the world, the Dipterocarpus which are 80 meters high.

We let 40 units of nitrogen leave each year in the groundwater. Imagine that in a forest like in Borneo, nature lets pass a tiny bit of nitrogen … Imagine that nature lets pass, I don’t know, a thousandth of nitrogen: in 150 million years it has there would be nothing left on Borneo… it would be a desert. It is not a desert, it is the richest forest in the world.

So how does it work ? How does the living system work? It works in the following way.

The tree is the master of soils.

This is why the ancients, after having ruined the soils of Europe, succeeded in recreating the agro-sylvo-pastoral balance in the 19th century and stopped famine in Europe. This is because they had unconsciously, quite empirically, injected the tree back into agriculture. It was in the form of hedges. Because the tree is essential.

How does it work in the forest? The tree, every year, drops dead leaves and dead branches on the ground. These branches will be attacked by a fauna called the epigee fauna. This fauna will eat all these pieces of wood, all these leaves and make droppings. These droppings are organic matter crushed into very very fine elements. Once transformed into droppings, fungi and basidiomycetes will be able to attack them and transform them into humus. They are the only organisms in the world capable of attacking lignin.

What is interesting in the living system is that the production of humus takes place on the surface of the soil. We immediately understand why plowing is a machine for mass destruction of soil: it is that it puts organic matter under the soil, which is nonsense! Because the epigés do not live under the ground, they live on the surface of the ground.

The trees will adapt to this very clever system and will double root. You saw with the hurricane of 1999 trees uprooted, they have a horizontal rooting which is under the organic matter. So we wonder why the trees developed this horizontal network of roots under this layer of organic matter? This is because in the spring, the humus that was formed during the fall and winter by the basidiomycetes, will be mineralized when the soil will warm up by the bacteria. Fungi make humus, bacteria mineralize.

By mineralizing they will release nitrate and phosphate which will descend with rainwater; and there are the horizontal roots of the tree which will be able to recover the nitrate, the phosphate and which will send them back into the canopy. The soil / plant system is closed in nature, there is no leakage. This is why the water tables are clean under the trees, because the tree has its roots under organic matter.

The great stupidity of agriculture is that plowing puts organic matter under the roots. So by the time the roots arrive, it’s already mineralized and it goes into the aquifers. So the first lesson is never to bury organic matter in a soil!

Nature tells us; just look at the book of nature.

Then the trees have a second rooting system called the pivot, pivoting system. This pivoting system will descend to the parent rock. There are two solutions: where the source rock is cracked, the tree will continue on its way. The record for rooting under oak in Europe is 150m deep; under elm: 110m; under birch: 140m. We do not have fun making holes of 150 meters to see that, it is speleologists who bring us roots from the bottom of the caves and they tell us: “At the bottom of the caves, we see roots hanging down from the surface and there is water flowing. “

The tree and the soil organize the living world. The tree is able to take the excess rainwater, send it along its roots, in which it will absorb all the nutrients, and bring this pure water into the groundwater.

This is why the tree is essential in the functioning of this planet, it is the only one capable of filling the water table.

At this depth, the root of the tree is in contact with the mineral world. What will the root of the tree do? It will secrete acids, attack the pebble and transform it into clays. What is interesting, since the soil is a clay-humus complex, is that the humus is made on the surface thanks to the work of mushrooms and aboveground fauna, and the clays are made deep by the attack of the roots trees in contact with the mineral world.

At this depth roots die, and new roots arrive. Fortunately there is a fauna which feeds on dead roots, which cleans all these dead roots and which frees up new galleries for the following roots: this is called endogeous fauna.

We find the same groups there as on the surface: collembola, mites, worms, except that they are small and blind; and their job is always to clean roots. To give you an idea of ​​the work of this endemic fauna, a wheat has 200 km of roots and 5000 km of absorbent hairs. A wheat eh! We put 200 per square meter. So [10 hectares of] wheat is 4 billion km of roots. Well, these 4 billion km of roots will be eaten by endograined fauna during the winter and will allow the subsequent barley, or rapeseed, to take root.

We see that 1) clay is produced at depth, 2) humus is produced at the surface, 3) an aboveground fauna aerates the soil at the surface and 4) an endogeous fauna aerates the soil at depth. But how do clay and humus meet? They must meet to form the soil! They meet thanks to a third fauna that you all know: earthworms. In tropical countries, termites have this role. What do earthworms do? These are the large earthworms, those called anecic fauna. They are not like the epigee or endogeous fauna, which changes place all the time. They have galleries, like burrows: every night, they go out, they leave the back of their body in the gallery to be able to enter it if there is a predator, and they take the organic matter, they take it away , they go down again, there they go up from the clay. They spend their time like this, when they have turned around they empty their intestines to form a droppings called the turricule. And it turns out that earthworms have in their intestines a gland called the morene gland, which is very rich in calcium. So they come up from the clay and they mix clay and humus in their intestines. Now it turns out that clays are negative, humus is negative, and calcium is an ion that has two positive charges. So a positive charge will attach the clay and a positive charge will attach the humus. They thus manufacture the clay-humic complex. It is earthworms that make the earth. when they have turned around they empty their intestines to form a droppings called the turricule. And it turns out that earthworms have in their intestines a gland called the morene gland, which is very rich in calcium. So they come up from the clay and they mix clay and humus in their intestines. Now it turns out that clays are negative, humus is negative, and calcium is an ion that has two positive charges. So a positive charge will attach the clay and a positive charge will attach the humus. They thus manufacture the clay-humic complex. It is earthworms that make the earth. when they have turned around they empty their intestines to form a droppings called the turricule. And it turns out that earthworms have in their intestines a gland called the morene gland, which is very rich in calcium. So they come up from the clay and they mix clay and humus in their intestines. Now it turns out that clays are negative, humus is negative, and calcium is an ion that has two positive charges. So a positive charge will attach the clay and a positive charge will attach the humus. They thus manufacture the clay-humic complex. It is earthworms that make the earth. So they come up from the clay and they mix clay and humus in their intestines. Now it turns out that clays are negative, humus is negative, and calcium is an ion that has two positive charges. So a positive charge will attach the clay and a positive charge will attach the humus. They thus manufacture the clay-humic complex. It is earthworms that make the earth. So they come up from the clay and they mix clay and humus in their intestines. Now it turns out that clays are negative, humus is negative, and calcium is an ion that has two positive charges. So a positive charge will attach the clay and a positive charge will attach the humus. They thus manufacture the clay-humic complex. It is earthworms that make the earth.

The first scientist who will be interested in it is Darwin. Darwin will be the first to give a scale of human remains, because if you make profiles you will see that the cut stones are found in depth, then the Roman mosaics, then the remains of the Middle Ages. It is not because the men of the cut stone lived underground, they lived like us on the surface, but it is the earthworms which buried all the human remains. That’s why archaeologists spend their time digging holes, it’s the fault of earthworms. And in fact Darwin has a very good idea, he measured the amount of earth: an earthworm rejects its weight of earth every day. He simply calculated the distances between the human remains and realized that it was much older than what was said. At the time the bible dated back 5000 years to the creation of humanity; so Mr. Darwin was very careful not to have religion on the suspenders, but he showed that it was much older than we thought. If you put a Japanese step in your garden, for example, you will see that your Japanese step will disappear: earthworms which will gradually bury it. Often when I am in the field with the farmers, they tell me: “Oh my, my stones are coming up. I explain to them that the heavy flight of stones in the plain does not exist. The pebbles never rise, it is always the earth that leaves.

So how did we manage to kill our soils? We violated its fundamental laws. You can violate human laws, if you get caught by the police you will go to jail, but it’s not very serious for all of humanity. But when we violate the universal laws, the laws of biology, there it is very serious. So how did we kill the soil? Two weapons of mass destruction of soil have been invented.

First the plow. At first the men scratched the ground with horses; It was not a big deal, but when we discovered the tractor, you know, it was like when Victor Hugo said to show the fascination of men in front of big machines: “An immense force which leads to an immense weakness, here is what which fascinates men. The guys bandage like crazy in front of a big tractor of 300 horses. They can do more, so they screw up the soil by turning it over and they put the organic matter at the bottom. This is the first mistake because all the mushrooms in the world are aerobic. There are no anaerobic fungi on earth. All the peasants who have had the opportunity to plant a stake in the ground know this when they take out the stake: the tip of the stake is intact and the stake is completely gnawed on the first few centimeters. Fortunately for the city of Venice which rests on wooden pillars. These wooden pillars are anaerobically underwater and no fungus can collapse them, that’s why the city is always there. So when you put straw in the ground you don’t make any more humus. This is why we arrive at this very surprising system: when the ancients made about 2 tonnes of straw in France, in 1900, they had 4% organic matter. Now we make 5 to 6 tonnes of straw on average across the country, but we only have 1.6% organic matter across the country. These wooden pillars are anaerobically underwater and no fungus can collapse them, that’s why the city is always there. So when you put straw in the ground you don’t make any more humus. This is why we arrive at this very surprising system: when the ancients made about 2 tonnes of straw in France, in 1900, they had 4% organic matter. Now we make 5 to 6 tonnes of straw on average across the country, but we only have 1.6% organic matter across the country. These wooden pillars are anaerobically underwater and no fungus can collapse them, that’s why the city is always there. So when you put straw in the ground you don’t make any more humus. This is why we arrive at this very surprising system: when the ancients made about 2 tonnes of straw in France, in 1900, they had 4% organic matter. Now we make 5 to 6 tonnes of straw on average across the country, but we only have 1.6% organic matter across the country. when the ancients made about 2 tonnes of straw in France, in 1900, they had 4% organic matter. Now we make 5 to 6 tonnes of straw on average across the country, but we only have 1.6% organic matter across the country. when the ancients made about 2 tonnes of straw in France, in 1900, they had 4% organic matter. Now we make 5 to 6 tonnes of straw on average across the country, but we only have 1.6% organic matter across the country.

We have halved our organic matter, while we have multiplied the straws by 2. Why ? Because we bury them. From the moment you bury them it’s over, you will never make humus again. So first mistake: burial of organic matter. And the people I see putting compost before planting a tree are making a fundamental mistake against universal laws.

Second error, we bring chemical fertilizers. What do chemical fertilizers do? They stimulate bacteria. However bacteria are mineralizing: they do not make humus, they mineralize. Bacteria multiply 20 times faster than fungi. So what happens when you put chemical fertilizers? You accelerate the mineralization of organic matter. When the organic matter falls too low, the fauna disappears because it feeds on this organic matter. In a country like France, we went from 2 tonnes of earthworms per hectare, in 1950, to less than 100 kilos! What happens when there are no more earthworms? I explained to you that earthworms go up every day from the earth. They rise from potash, phosphorus, magnesia, calcium. If the worms no longer go up, the elements will go down: pollution of the aquifers, pollution of the rivers. After this biological degradation of the soil, you enter what is called chemical degradation. Your land will lose its nutrients. You are going to send nitrogen into the aquifers, you are going to send phosphorus into the rivers, etc. You deplete your soils.

Now when the level of organic matter has fallen too low, and you have mineralized fundamental ions which attach clays and humus like iron, calcium etc., well the clay is no longer attached, the clay is go, the rivers become charged with mud as soon as it rains, it is the last death, which is called the physical death of the soil: your soil goes to the sea.

This is how you ruin a floor. I have been working with farmers since 1989, people in Beauce who were very proud to be part of the 100 quintals club. They rolled boxes at the time because they had wheat which in genetics was 110 quintal wheat, so they almost made their genetic yield. Now they have wheat at 150 quintals and the same farmers only make 90 quintals… That is to say that they have Ferraris, they drive on dirt roads. It is not worth having a Ferrari if it is to drive on a dirt road, it is better to have a 2 horses. They can tell anything they want, they no longer value the genetics of their plants. And yet we know that this genetics is valid since recently an experiment in New Zealand we found that on a soil that had never been plowed, never touched, and they made 162 quintals in direct sowing, and 152 quintals in plowing . So it shows that the genetic potential is very real, but our soils are on their knees.

So what does it mean to “make agriculture sustainable”? It is to recognize that the propaganda of multinationals is propaganda and not science. We will have to put science back into agriculture. But agriculture has had no science for 50 years, it has only technology, it has only chemicals, they only have big machines, that is to say that it runs agro-industrial business and enriching agro-industry, but that it is not there to feed people. Now, with 7 billion people, we will have to decide to feed people. And we now have 1 billion people who suffer from starvation: so the “green revolution” is a total failure. The problem is that this profit-obsessed society doesn’t want to admit its wrongs,

So we will have to completely change our agriculture, I will have to dissolve companies like Monsanto, Novartis and company, who are murderers. We will have to create a kind of international justice on crimes against life, because these people are criminals against life, they killed! The biological activity of soils, which I have been measuring since 1989, continues to decline. And when I compare with the figures from the beginning of 1900, we have lost about 90% of our biological activity. Especially the big missing is the mushrooms, completely gone with chemical fertilizers. Now it is they who make the humus. Since there are no more mushrooms, the soil is really very bad.

Earlier you were talking about the BRF. Why does the BRF have such a spectacular effect on the revival of soil life? Is that it brings lignin. It gives back this substance that only mushrooms are able to attack and you go up the C / N ratio, the carbon / nitrogen ratio.

Agriculture does not need nitrogen: it needs carbon. That’s what agronomists still haven’t understood. As agronomists know nothing about the life of soils, the chair of soil microbiology at Agro was closed in 1986 … There you have before you a living fossil, okay? Soil microbiologists are making more in France. The 150 agros who come out of the box, they know nothing about microbial cycles, it’s still mind-blowing. They do not know how to distinguish a basidiomycete, from a bacterium, from an actinomycete, they do not know that their roles are completely different.

If we want to restore life to the soil, we will have to stop inventing artificial models, such as the green revolution, and give the Nobel Prize to a guy who ruined 300 million hectares of soil with its green revolution. That’s not the goal, the goal is to put science back so that we can once again look at the soil as it is; because the only big book is nature; it’s not behind a computer that you discover how a floor works, it’s by making holes! With Lydia we made more than 12,000 of them across the planet from the altiplano (highland) of the Andes via Norwegian soils and soils from America and Borneo. Soils we know how it is because we open them, and we look at the fauna, we look at the roots. This is more than what agronomists do …

Well, thank you for your attention.

Question: on what depth to work the soils?

Answer: not return them at all. There are direct seeders, seeding wheels, … Green manure before cultivation, crush it with a Faca roller at the front, without burying it above all, and sow with a seed wheel at the rear.

Question: For the potato?

Answer: Spread them with a rake on the surface, cover them with 20cm of straw, like the Bolivian peasants do. Use it when you need it …

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