Fertility And Friability

Organisms in the soil influence these important performance factors.

- Paul Donovan

The presence of micro- and macro-organisms (arthropods) in the soil contributes to its friability, which is the ease with which a large solid substance can be reduced to smaller pieces (such as crumbling between your fingers). As these organisms work their way through the soil, large clumps are broken down and fertilised with waste products. This not only adds to the fertility of the soil, but also enhances its drainage and water-retention properties. The organisms’ tunnelling also assists aeration and better water movement, both of which go to creating an improved environment for root growth.

The waste products released by soil organisms are rich in nutrients and work like tiny time capsules, releasing these nutrients back into the soil over a period of time. This gives the soil fertility and affects its pH and chemical composition. Soil with a fairly neutral pH and good levels of micro- and macro-organism is able to unlock valuable nutrients such as nitrogen, phosphate and magnesium. These are then made available to the plants more efficiently than in soil that has a higher acidity or alkalinity. In this type of soil, because there are less organisms present, the soil holds onto its nutrients. Of course, some plants are adapted to living in such conditions.

Functional benefits of arthropods in the soil

Microbial activity

As arthropods feed on fungi and bacteria they create a symbiotic relationship between the fungi and bacteria, and improve the decomposition of organic matter. The level of arthropods feeding on bacteria/fungi directly influences the stability of this symbiotic relationship.