Agronomical Benefits of increasing SOM

Chemical

• Soil organic matter significantly improves the soil’s capacity to store and supply essential nutrients (such as nitrogen, phosphorus, potassium, calcium and magnesium), and to retain toxic elements.

• It allows the soil to cope with changes in soil acidity- pH. 

• Helps soil minerals to decompose faster.

• As an addition, in time this can lead to higher crop yields and a reduction in nutrient application (depending on the soil type and its ability to store carbon). 

• Soils with higher clay content will always be more responsive as their ability to capture carbon is much higher than soils of  low clay content, particularly sandy soils.

Physical

• Soil organic matter improves soil structure.

• This ultimately helps to control soil erosion, improves water infiltration and water holding capacity, giving plant roots and soil organisms better living conditions. An increase of 1% organic matter (about 0.5% increase in carbon) can result in the soil being able to hold over 150 000 extra litres of water per hectare (http://traceandsave.com/carbon-the-key-to-storing-more-water-in-the-soil/).

• It helps to make soils more friable and thus easier to work, as an addition this leads to less energy required to grow crops.

Biological

• Soil organic matter is a primary source of carbon (C) which gives energy and nutrients to soil organisms.

• This supports soil functionality because it improves the activity of microorganisms in the soil and it can enhance biodiversity.

• As an addition capturing carbon in the soil also lowers emissions of CO2 to the atmosphere, and this mitigates climate change.