Soil quality in organic farming

Farmers and scientists have realized that productivity in agriculture is largely determined by soil quality.

The characteristics of good soil are easy to describe, but hard to measure quantitatively. In general, good soil should contain major nutrients, have high water holding capacity, good drainage to prevent oxygen deficiency of roots in rainy seasons, and resist erosive effect of wind and water.

Quality is an essential part of soil, one of its major characteristics. It is determined by natural texture and components of a particular soil. For example, is it sandy or does it have clay layers? Does it have high content of decomposing plant residues or is there deficiency of natural organic substances?

For many hundreds of years farmers did not even think about characteristics of really good soil. Historically agriculture thrived either on fertile overflow lands, where floodwater often left fresh organic drift, or in plain prairies, where a layer of decomposing residues formed soil, rich in organic substances.

In recent years as a result of urbanization, more and more productive agricultural lands are being taken over by cities, at the same time the quality of many croplands decreases because of intensive production. However, the importance of soil as a component of ecosystems that makes it possible to maintain air and water quality as well as health of humans, animals and plants just begins to be realized.

The farming practices that impair soil quality not only threaten long-term efficiency of grain production but also have adverse effect on the health of both adjacent and remote ecosystems.

Soil quality is a relatively new concept in the world of science and it is based on concern about sustainable development of agriculture and growing awareness of the role of soils as a living filter, which cycles water and other natural components.

Observations and examination of soil parameters helped significantly to amplify the information on how different farming methods influence soil quality.

One of the most important discoveries was the fact that addition of different organic residues with low C to N ratio (e.g. animal and green manure, organic waste) in combination with diversified crop rotations significantly decrease C and N losses from the soil and increase active and stable elements of its organic components.

Research data also showed that soils farmed using organic practices have better physical structure. In organic systems soils get more lose, porous and have better absorption capacity. They have better water holding capacity compared to soils farmed with traditional practices.

These improvements in soil quality characteristics have direct effect on crop yields, help organic systems maintain high productivity even in dry years. They also allow soils farmed using organic practices to fulfill the functions of overall ecosystem more efficiently.