The CEC is fully dependent on the Humus level (organic matter) and pH of the soil. A good, fertile soil has a CEC over 300 mmol/100 grams. A leached soil may have a CEC as low as 50 mmol/100 grams.
All soils with high CEC, are rich in Humus substances and organic matter. Humus rich soil require 50% less nutrients, compared to a leached soil, to yield the same crops. This soil also has a much lower nitrogen leakage percentage.
Soils with a low CEC are dependent on chemical fertilisers to produce good yields. Also, the lower the CEC, the more nitrogen is leached into nature. Soils with a low CEC have poor ability to absorb water and become sensitive to drought.
CEC – how it works
Humates and Fulvates are liquid compost – with extremely high CEC.
Humates have a CEC of between 400 – 600 mmol and Fulvates a CEC of 1200 – 1500 mmol. When applied, they greatly increase the soil’s ability to bind and make nutrients available for absorption by plants.
They are also a source of food and fuel for the soil microbes. When the microbes break down the Humic substances, new organic complexes are formed and new soil is created. Humates also react with minerals, to form porous organic complexes, that bind excess nutrients. The ability of the soil to breathe and absorb water increases significantly and this has a positive impact on the plant root system.
Humus substances also have a buffering effect on soil pH and increase soil resistance to acidification.