How to Improve Poor Aeration in Soil
February 6th, 2009 | by James Roberts |Poor aeration can also be due to restricted flow of air from the atmosphere into soil pores. Most of the gaseous interchange with the atmosphere occurs through diffusion, which is hampered by a lack of macro pores in the soil. On heavily textured top soils and in compact sub soils, the rate of gaseous movement is particularly slow.
Some chemical fertilizers harden the soil and reduce aeration. Nitrate of soda is a typical offender. In yearly applications of this fertilizer, plants use up much of the nitrate but little of the soda. This keeps piling up in the soil, and combines with carbon to form carbonate of soda (washing soda). Where large amounts of nitrate of soda are used, the soil can become so hard that it can be cultivated only after a rain.
Soil aeration is directly related to the porosity of the soil. Proper aeration of the soil is important to proper plant growth. Well- aerated soil consists of a large proportion of macro pores, allowing sufficient quantities of the right gases to be available to aerobic organisms to encourage best functioning and growth.
Poor aeration results in a decrease in the activity of soil microorganisms. When oxidation of organic matter slows, aerobic organisms are unable to function properly. Higher plants are adversely affected in several ways. Root and top growth is slowed, absorption of nutrients and water is decreased and certain inorganic compounds toxic to plant growth may form.
The first step will be to add humus. This may not be easy, but the results make any effort worthwhile. By doing this every one of the problems named above will be minimized, some entirely eliminated.
The soil will become easier to till. Moisture will seep down and be held instead of running off. In this converted adobe, earthworms may be planted and will flourish. Since humus is a neutralizer, the alkalinity will be brought down to a point suitable for many garden plants.
Even the vital iron, which has been there all the time (the red in adobe is iron oxide), and the locked-up phosphates may be freed to some extent.
A waterlogged condition is so detrimental to plant growth that even a short period may seriously endanger some plants. This may occur either in poorly drained soils composed of fine particles or in well-drained soil if enough water is rapidly applied. Prevention of this type of poor aeration necessitates removing water from the land, either by controlled runoff or drainage; the latter can be particularly effective.