Here's a review of Thierry's talk based on a few notes I jotted down. Any mistakes are most likely due to me. — Arthur Ralfs
Thierry was a nematologist who began his career as a graduate student fumigating soils to eliminate nematodes. He structured his talk as Solar versus Chemical agriculture,remarking that solar has a ten thousand year history versus a sixty year one for chemical agriculture. More/Less ...
Thierry emphasizes the soil ecosystem - a handful of healthy soil contains fungus mycelia, archaea, bacteria, nemotodes, protozoa and other microfauna as well as the relatively giant earth worms. The main players are fungi, archaea and bacteria, nematodes and plants.
The talk was centred around the "soil food web" with everything feeding on its neighbours.
Nematodes
A handful of healthy soil contains around ten thousand nematodes. They feed mostly on bacteria but some also feed on plants in which case they are regarded as pests. They are microscopic organisms comprised of only one thousand cells, are capable of learning and are used for genetic and medical studies. The particular nematode "Caenorhabditis elegans" has been particularly employed as a model organism in scientific investigations.
Bacteria and Archaebacteria
A handful of soil contains around one trillion bacteria and archaebacteria. They are capable of sporulating when conditions are unfavourable to wait for better conditions and can remain dormant in the soil for a long time. Rhizobia, Frankia, and company make food out of air by reducing N2 and manufacturing proteins. They are the only organisms on earth capable of doing this. These bacteria latch onto plant roots forming nodules and feed off plants but return proteins made from atmospheric nitrogen so relation with plants is symbiotic. They appear pinkish due to hemoglobin which indicates a common lineage with us going back hundreds of millions of years.
The agrobacteria are the original genetic engineers. They come close to plant roots and inject a piece of their bacterial DNA into the plant cell which then co-opts the plants biochemical machinery and makes sugars on order from the bacteria dna. This is straight parasytism and can be a severe problem.
Thierry briefly mentions yeast and some other organisms but gets more excited about
Fungi
The fungi are extremely important in the soil food web with a handful of healthy soil containing around 25 km of mycelium. The mycorrhiza are singled out as especially important because they penetrate inside roots of plants and every cell of roots is colonized. It's a symbiotic relationship because the fungus draws water and minerals from the soil to feed the plant. Nearly all plants have a mycorrhizal relationship and the network of mycorrizal mycelium connects every plant to every other.
Earthworms
Earthworms are a prime indicator of soil health. The more life in the soil the more earth worms because they feed on organic matter both dead and alive. Thierry points out that they are an indicator of soil health rather than primary cause.
Some other macroscopic soil creatures, wireworm, ants, ... , are briefly mentioned
Thierry briefly flashes a slide illustrating trophic levels in the soil. This indicates five different trophic levels and the interactions between them and indicates the complexity of the soil ecosystem.
Mineralization
Thierry talks about how the natural solar system involves plant material falling as mulch and being recycled by the soil food web. If we're harvesting then we remove plant material so we need to add something. For instance Thierry uses seaweed, leafmulch, grass clippings, garden waste, animal manure, food compost, ... . This is fine for gardens but for larger scale agriculture there is unlikely to be enough of such material available. Traditional approach uses a fallow period every 3 years in which crops are grown, not for harvesting, but for the sole purpose of enriching the soil. Thierry favours comfrey and nettles because they pull up minerals from deep down.
Composting
Thierry doesn't go into composting deeply other than to mention the traditional method of three compost boxes used in a sequential fashion with turning of compost every so often. He also tantalizes us with a picture of some beautifully crafted wooden compost boxes. He highly recommends the book "Teeming with Microbes" by Jeff Lowenfels and Wayne Lewis with a foreword by Elaine Ingham author of "The Organic Gardener's Guide to the Soil Food Web". Thierry does single out compost tea for mention. Compost tea is a live solution of micro-organisms derived from active compost. Put some compost in a bucket, add something sweet like molasses and water and after 36-48 hours with aeration get rich compost tea which can be sprayed foliarly or on the soil.
Thierry likes rock dust, especially glacial rock dust and volcanic rock dust, as a good source of minerals for the soil.
Getting near the end of the talk,Thierry touches on quite a few topics briefly. Commenting on the local product Sky Rocket sold by the regional district he points out that is composted sewage sludge and is only tested for acceptable levels of a few heavy metals. Although we live in an area without much heavy industrial pollution,Thierry still doesn't use Sky Rocket.
He remarks that chemical fertilizer after WW1 and especially after WW2 was a reinvention of chemical explosives by munitions companies looking for new outlets for their products.
For the organic method he notes that the type of soil is not important since it's the food web that feeds the plant but it is important for chemical agriculture. The chemical method involves testing your soil and amending with various chemical to correct any deficiencies. However chemical fertilizer poisons the soil food web with the application of chemicals producing an unnatural load of soluble salts into the soil which is destructive to the soil micro-organisms. Although they temporarily feed the plant there is huge collateral damage from the use of chemicals such as ammonium nitrate, ammonium sulfate, urea, super phosphate, potassuum chloride, ... . He mentions the dead zone in the Gulf of Mexico as one example of numerous ocean dead zones around the world resulting from excess chemical nutrients being flushed into rivers and oceans.
Thierry points out that the soil food web is the largest reservoir of carbon on planet and it is being destroyed by chemical
agriculture.
Biodiversity is the basis of food security and pest control. With large biodiversity no one species can become epidemic while lack of biodiversity needs to be medicated with pesticides, like medicating overcrowded livestock in industrial production.
Open pollinated varieties reproduce true whereas hybrids do not. One cannot save seeds and get the same plants. Need to buy your seeds every year. GMOs extend this commercial model in that now farmers have to buy seeds and, typically, the pesticides/herbicides that go with the GMO every year. In Canada as of now there are only four GMO crops grown: corn, canola, soy bean, sugar beet. However elsewhere there are many other GMOs being grown, e.g. cotton, potato, wheat, grape vine, papaya.
Thierry used to do genetic engineering and promote it but he had a life changing experience in 1998 in Scotland when a Scottish scientist did experiments on mice with a GMO Thierry was working with. The research showed bad effects and when the scientist went public with the results he was promptly fired. (Reviewer's note: this sounds like scientist Arpad Pusztai formerly of the Rowett Research Institute in Scotland and mentioned in my review of Marie-Monique Robin's film "The World According to Monsanto". See ?q=node/28.) Since then there have been many peer reviewed studies showing mice and rats fed GMOs showing bad results. Jeremy Rifkin calls releasing GMOs into the environment genetic pollution and there is no recall.
In the comparison of Solar versus Oil based agriculture Thierry points out that, due to peak oil, the price of oil will go up and impact the entire chemical production system since the chemical products are generally manufactured from petroleum. While solar is resilient the chemical system will have to, putting it charitably, evolve.
Thierry ends by pointing out that some jurisdictions are already starting to pay farmers for carbon credits because good organic practice sequesters carbon in the soil. He finally points out that Cuba used chemical agriculture as a client state of the Soviet Union but when that entity collapsed Cuba lost its supply of chemical and petroleum. In a few years Cuba successfully completely changed from chemical to organic.
