Is soil a living organism?

Special thanks to Praveen Karri for his support in bringing this article into this website.

Is soil a living organism?

It is very obvious that healthy plants need healthy soil for healthy growth. To understand this concept, let us dig around why plants need the nutrient rich soil and how plants absorb them. 

Effect of Fertilizers on plants & soil

Soil needs to contain minerals and the life research shows that the widespread use of synthetic fertilizer leads to soils that no longer have the required biota for healthy plant growth. Fertilizer comes from a time when there was no understanding of the long-term effects of their usage on the soil. There was a belief that fertilizer was a miracle that doubled the harvests and growers were able to provide the required food for growing population. But unfortunately, now after years of using synthetic fertilizers the effects on soil quality are apparent, increasingly it is seen that fewer nutritional minerals remain in the soil resulting in plants that quickly become weak and diseased. They are no longer protected by bacteria and fungi. instead, the plants are attacked by them as well. These days farmers need to plough deeper as the ground becomes quickly compacted due to fertilizers use which is a very costly affair for farmers and is disastrous for the soil. 

There is a less known better way of farming where the roots of plants are able to develop more easily in an environment rich in old roots. Here you can see the current ploughing method in which the soil is turned to 25 centimeters this means that the plant really struggles to reach the thousands of passageways that other plants have created with their roots they often don't even reach through the POW pan which is caused by ploughing the land with heavy machinery. Surface cultivation method can offer a solution to this shallow soil processing so that the roots are quickly able to access the passageways left by decomposing roots. In this situation they only have to work really hard once they reach the extremities of the passageways; this means that they can root deeper year after year and ensure that there is even more soil and water available for growth. Dealing with diseases by spraying does little more than suppress symptoms. A healthy plant is able to keep most plant diseases out. In response to the negative effects of using fertilizers pesticides are used to save the harvest. 

The conclusion we can draw is that plants that are only given fertilizer will ultimately always become diseased. Fertilizer is the direct cause of the use of most pesticides. In order to resolve the worldwide problem of over fertilization. The vicious circle must be broken. The question that we must ask ourselves is how can we improve the soil. The answer is surprisingly simple, but requires some explanation. Just like every other organism on the planet a plant does not function independently. Health and growth depends on a partnership between specialist bacteria and fungi. 

Role of microorganisms like Fungi and Bacteria to make the soil healthy

Let's see the relationship between microorganisms, plants and the soil. Plants, fungi and bacteria form a wonderful system based on trading products. How it works is the fungi and bacteria supply nutrients from the soil that would otherwise be hard to reach in exchange for this plant supplies sugars in the form of glucose. To explain this system, we will explain bacteria and fungi separately. Plants have a problem: the fine absorption roots have a limited capacity; they only use 4-7% of the soil volume and are on average not thicker than a hair. They don't live long, only one to three weeks as you can see plants need external help. Plants use their absorption roots to forge a partnership. If they can't find partners they'll die, if they succeed it is the start of a beautiful relationship from now. On a symbiosis can be created minerals are hard to mined from the soil but Rhizobacteria are specialized in this process particularly when it comes to releasing phosphate which is very important for the plant these bacteria also carry out countless other important tasks including one which is very special, Rhizobacteria form a sort of natural defense system around the roots anything attacking the plant is kept outside by the physical presence of these rhizhobacteria they ensure that there is no room for disease-causing bacteria they have their own interest in this because the plant provides them with food however the bacteria also need help they are not travelers the bacterial colonies do not move back and forth from minerals to the roots. Most minerals found in soil are located outside the reach of the roots and therefore also out of the reach of Rhizobacteria these can only live near the roots as we have seen before the zone of absorption is therefore very limited mycorrhiza fungi are able to drastically increase this absorption capacity. It may sound like a modern development but it's not the fungus that has always existed but due to modernization its role has been neglected. Due too many years of using synthetic fertilizers. 

Mycorrhiza is only very sporadically found in agricultural soils mycorrhiza fungi have always lived in symbiotic relation with the plant roots mycorrhizal fungus forms a living connection within the roots and creates an absorption and transport system this is essential for healthy plant growth. Mycorrhiza in the root is just as normal as chlorophyll in the leaves this is beyond doubt as stated before the absorption roots of plants are 0.2 ml thick this means that they can only grow in microspores as shown here now we zoom in to see what happens when the plant gets help from the mycorrhizal fungus the fungal threads are even thinner than most bacteria they are only as thick as three microns this means that these thin threads grow easily in the micro pores where the majority of nutrients and water are stored without help a plant would never be able to reach these areas it's not just the root but also the fungal threads that are responsible for the absorption of nutrients and water the long thin fungal hyphae (branching filament of fungi) that fully takes over the absorption of materials from the roots are able to provide disease resistance distantly located minerals that are bound to iron and calcium are now easier to absorb. These fine threads can be as long as a kilometer long in just one teaspoon of soil. Mycorrhiza fungi causes absorption capacity to be seven times higher in average this means that growing can be done with less water and that weeds have far less chance to thrive due to competition for space.

The benefit to the fungi is the glucose produced by the plants. For the plants the benefit is a larger absorption zone This unique and constant interaction between the plant bacteria and fungi creates a really fantastic symbiosis the payout that the plant provides to its partners is water minerals and glucose. The partnership between soil and roots requires healthy soil biota. Healthy soil contains organic matter from dead leaves, dead roots and dead animals this dead organic matter is broken down in nature by soil life to become humus this creates a great deal of food for soil life and the soil retains plenty of CO2. Longtime usage of fertilizer has caused the humus to disappear from agricultural land you could think of humus as the battery of the soil it's where the energy is stored the energy that the soil life needs to do its work. Without the humus it is almost impossible to achieve natural soil recovery. It has long been thought that nitrogen fertilizer stimulates the soil life as more bacteria are able to grow but to maintain their carbon nitrogen balance they are compelled to consume more organic material which then enters the atmosphere as CO2. The symbiosis between plant fungi and bacteria is not only a great partnership, it is absolutely vital without these transformers of organic material we would all perish in excess organic material returning to the question we asked previously about how we can improve the soil the answer must be ultimately plants improved the soil on their own they do this through the symbiosis between plants, bacteria and fungi. Plants are really the only soil that improves us. 

Here we can see a clear difference between an absorption system without and with mycorrhizae fungi. Let’s see an example, the plant which is entirely dependent on the pH value of the soil and the supply of minerals. On the other side, the plant that is able to optimally self-regulate the pH level and absorption of mycorrhizae fungi results in a healthy absorption by plant roots that works perfectly with organic fertilizers.

Conclusion

By using the natural system which includes above mentioned micro-organisms, minerals in the soil leads to healthy soil that in turn results in healthy plants which leads us in the production of healthy fruit and vegetables. By all means we cannot stop to say 'Soil is a living organism'.