The conservation agriculture approach is a system of managing agricultural lands based on certain farming practises. It aims to achieve a sustainable production that minimizes soil disruption while preserving soil quality and improving its biodiversity. Indeed, the main goal of conservation agriculture is to tackle land degradation and increase efficiency in the use of water and nutrients. For this reason, this technique works well with degraded agro-ecosystems in order to restore resources, and increase profits and food security.
Despite the cropland cover, conservation agriculture is based on three pillars:
- Minimum soil disturbance (i.e. minimum or no tillage), just enough to allow the seed to get into the ground.
- Permanent organic soil cover (by using either previous crop residues or a cover crop specifically grown for this purpose)
- Crop rotation, with varied sequences and associations, also including legumes
No tillage or minimum tillage is the most common conservation agriculture practise for annual crops. It allows an approach to farm the land without disturbing the soil, or with the least disturbance, through tillage. Handling soil with machinery overexposes it to air, causing a rapid oxidation of the organic substance, which in turn compromises soil structure. In comparison, the no tillage technique imposes to sow the new crop over previous crop residues. Beside the conservation of soil structure and fertility, this practise also plays an important role against soil erosion caused by machineries, especially in hilly and mountain areas.
Groundcover is a widely used practise for perennial crops, thanks to which, the soil surface between rows of crops is covered and thus protected by erosion. For the cover it is possible to use either sown cover crops, spontaneous vegetation or inert crops, i.e. pruning residues or tree leaves.
Food and Agriculture Organization of the United Nations, 1991, Chritchley & Siegert, Water harvesting, http://www.fao.org/3/u3160e/u3160e00.htm. Reproduced with permission
WOCAT, 2012, Schwilch, Hessel & Verzandvoort, Desire for Greener Land, https://edepot.wur.nl/212528. Reproduced with permission.