Biochar in Conventional Agriculture

Biochar is becoming increasingly popular as a soil admix both on a small garden and a larger farm scale.

On a farm scale it is usually incorporated into the soil by ploughing.

Gardeners are increasingly being sold biochar with instructions on using it to hold fertility into their soils. It is either sold as just biochar or it can be bought ‘activated’ with nutrients and beneficial micro organisms.

There has been very little research into the question of how the effects of biochar differ between dig and minimal dig systems.

Conventional agricultural systems which till the soil are not condusive to mycorrhizal activity.Breaking up the fungal hyphae, encouraging bacterial competition, killing weeds and thereby disturbing the symbiosis between plants and AM and

Tillage does encourage bacterial activity as a result of aerating the soil.

Adding fertilisers (including manure which is high in nitrates but relatively low in carbon) also inhibits AMF activith and encourages bacterial activity.

Increased bacterial activity makes nutrients and fertilisers in the soil bio available.

This is the reason why traditional agriculture relies on soil cultivation and fertiliser or manure application. It works very well in the short term.

In the bigger picture, however, there are problems with this approach to growing annual crops: Unsustainable fertiliser production, pollution caused by fertiliser release to the wider environment, soil erosion and soil carbon depletion.

For these reasons, conservation tillage practices are increasing in popularity. Damage is limited, depending on the extent and type of conservation tillage used.

Combining biochar with conservation tillage has the effect of further reducing nutrient loss from soils due to the adsorptive properties of biochar. (Its CEC and AEC, cation and anion exchange capacities).