Find out what makes a soil healthy with this comprehensive guide.
The basic soil skeleton
Every human and animal has a structure (skeleton). The soil has structure, too (soil friability), which refers to how much the soil can hold in the way of minerals etc and what we call the cation exchange capacity (CEC). The CEC is a measure of fertility or nutrient retention capacity. We can look at it as the soil’s skeleton.
The dry matter of a healthy, balanced human skeleton contains three main elements in the following proportions:
• Calcium 37%
• Phosphorus 17%
• Magnesium 1%
A healthy, balanced soil structure (soil skeleton) contains five exchangeable cations in the following ratios of the cation exchange capacity:
• Calcium 65–70%
• Magnesium 12–15%
• Sodium <5%
• Potassium 3-5%
• Hydrogen <15%
If the soil skeleton, or CEC, contains this ratio, the soil is very friable and can hold an abundant supply of water and nutrients. The second level of structure in humans and animals is the soft tissues —— muscles and flesh — which fill and cover the skeleton. As we remember from primary school, the tissues are built from carbohydrates, protein and fats. These ratios differ according to an individual’s life stage or lifestyle. For example, growth, pregnancy/lactation and athletic training have a bearing, as do different purposes in animal production — dairy, wool or meat production, breeding, replacing commercial stock etc.
Vitamins and minerals for soil
Humans and animals cannot survive with an intake of only carbohydrates, proteins and fats. They also need vitamins and minerals in amounts appropriate to the body’s needs and individual functions/purposes. Similarly, the soil needs minor (trace) elements such as copper, zinc, iron, manganese, cobalt, molybdenum and boron in the right doses according to the land use or type of crop.
Soil and bacteria
The third component to consider in human and animal bodies is bacteria. They are found in every system in the body and can be either good or bad, so we need to ensure the right balance of bacteria, too. In soil there are five active groups of microbes controlling the whole bacterial population in the soil:
• Active fungi and cellulose utilisers
• Active yeasts
• Active lactic acid bacteria
• Active actinomycetes
• Active photosynthetic bacteria
These must all be in balance according to the total active bacterial population, which is controlled by the adjusted cation exchange capacity in the soil. Even during a resting state, living beings need all components to be in balance so they have continuous function and sufficient energy (for example, basal metabolic requirements for living beings to remain alive, including circulation, respiratory function etc). The soil also has base requirements to remain healthy and balanced, even during a “resting” state. These are above and beyond the requirements of the plants we wish the soil to support, grow and feed.
Achieving balance
If your soil is balanced in structure (skeleton), nutrients (chemical) and micro-organisms, then you have healthy, balanced soil, according to the Mikhail System. This is the first system to look at the three components of the soil at the same time and recommend what is required to balance each of them and balance them together, as a living system. Hence, the philosophy is Healthy, Balanced Soil = Healthy, Balanced Plants = Healthy, Balanced Animals and Human Beings.
