Conservation Agriculture (CA) – or “Conservation Tillage” as it was often called – is a cost-effective, environmentally friendly method of farming which does not use regular ploughing and tillage, but promotes permanent soil cover and diversified crop rotation to ensure better soil health and productivity. Society also benefits from reduced atmospheric carbon dioxide emissions.
CA (as defined by the Food and Agriculture Organisation of the United Nations, FAO) has come to be accepted as the umbrella term for describing agricultural farming practices that conserve ecological systems. The most common forms of CA are no-tillage, conservation farming, direct seeding, ridge till, chisel & disc, rip-on-row and stubble mulching.
All of these methods leave plant residues on the soil surface between growing seasons. The plant residues provide a protective cover that diminishes wind and water erosion, reduces evaporation losses, minimises water runoff and can thereby dramatically increase soil water (from irrigation or rain) availability. Organic matter, the key ingredient in soil productivity, increases, as do earthworms, conservation tillage’s ‘biological plough’, reducing diesel requirements by up to 50% or more.
Conservation and efficient utilisation of natural resources at national, regional and farm level is no longer a luxury but an imperative, and the adoption of conservation farming practices an essential component of good farming practice.
Some forms of Conservation Agriculture
Conservation Agriculture, as defined by the Food and Agriculture Organisation of the United Nations (FAO), is receiving growing acceptance internationally as the optimal crop production system, and includes all farming systems which involve simultaneous adherence to the principles of:
Continued minimal soil disturbance (including NO soil inversion) – to retain root channels and encourage the build-up of soil biota populations and hence soil structure;
Permanent organic soil cover (either by living crops or by crop or other plant residues) – to diminish the impact of raindrops and reduce water runoff (and consequently soil loss); and
Diversification of crop species growing in sequence and/or associations (especially crop rotation) – to increase the diversity of food sources and hence soil biota, especially predators, and break pest and disease cycles.
