Soil Cover as a Component of Conservation Agriculture (CA)
Conservation Agriculture (CA) as defined by FAO aims to conserve, improve and make more efficient use of natural resources through integrated management of available soil, water and biological resources combined with external inputs. It contributes to environmental conservation as well as to enhanced and sustained agricultural production. It can also be referred to as resource efficient or resource effective agriculture.
CA encompasses the sustainable agricultural production need that all humankind obviously wishes to achieve. But this term is often not distinguished from conservation tillage. FAO mentions in its CA website that “Conservation tillage is a set of practices that leave crop residues on the surface which increases water infiltration and reduces erosion”.
Farmers seldom see soil erosion a consequence of land degradation as a problem and are, therefore, very unlikely to adopt practices unless the practices address their main concern which are increased and regular production. Soil cover (either the use of live crop or dead mulch) can achieve regular and increased production. Soil cover protects the soil surface from the impact of raindrops (dispersion and compaction), reduced soil-moisture losses (through evaporation), prevents excessive high temperatures, suppresses weeds, and increases biological activity. By conserving soil moisture for use by the plant roots and providing suitable condition for the soil organisms, cover crop improves the soil quality (structure, aggregation and porosity). Agricultural production subsequently improves because soil cover both promotes and maintains soil in optimum condition for water infiltration (water availability) and plant growth (nutrients).
Soil surface cover, be it living crop or dead mulch, is the best single factor for protecting the soil surface from degradation (rain splash), and are therefore, reducing erosion. Soil cover near the ground surface dissipates the erosive energy of raindrops by breaking them up into smaller raindrops. Rain droplets have insufficient energy to splash soil particles or to cause surface soil compaction. Even if water droplets coalesce in the leaf surface and forms bigger raindrops, these also have less energy and are normally less damaging than raindrops coming from about 8 meter high.
For more info: Call: Dr. Gavino Isagani P. Urriza At: (02) 923-04-59 Or email us a gurriza258@yahoo.com or visit us at: conservationist.wordpress.com
