Subsurface densification of the soil occurs when the load-bearing strength of the soil is exceeded. In the layer just beneath the plough, densification can occur; this plough sole begins at a depth of about 30 cm. Over time, the soil will lose its structure and its pore will disappear. This threat might be invisible from the surface, but it can be measured!
In case of prolonged or intense precipitation, the top layer can get saturated completely because natural infiltration has become impossible due to densification of the subsurface. This means that rainwater remains stagnant on the plough sole. With full saturation of the top layer, rainwater flows over the surface of the field to the lower parts or into the ditches. This surface drainage problem also involves flushing out nutrients and crop protection products. The outflow of nutrients, pesticides and herbicides in surface water causes various other water quality-related problems.
In a healthy situation, the water surplus infiltrates into the water-bearing layers. If this percolation is disturbed by soil compaction the aquifer is no longer (sufficiently) recharged. The freshwater supply is needed for irrigation in dryer times.
There are a number of direct problems caused by the decline of the infiltration capacity of soil. Water from rain, or over irrigation, will now fill the pores of the soil, this creates an oxygen deficiency. Wet, oxygen-deprived soil conditions are ideal for crop- and fungal diseases. These can develop rapidly, which will negatively affects the yield or even spoils the crops.
Soil densification also prevents root growth of crops. Compaction of the sub-surface inhibits the root growth of crops. This soil compaction scenario also has a negative effect on the yield of the crops which are unable to fully develop.
Equipment is available and methods have been developed to investigate whether compaction occurs in your soil and whether the identified compacted areas are problematic. Determining the penetration resistance is a simple and efficient method of measuring to detect the presence of compacted layers and gives an impression of, among other things, the ease with which roots can grow in the soil. The measurement is carried out on site in your field with a penetrometer, penetrograph or penetrologer.
Eijkelkamp Soil & Water makes a difference worldwide by developing, producing and delivering solutions for soil and water projects. With the penetrometer, penetrograph or penetrologer from Eijkelkamp Soil & Water you will be able to take soil penetration resistance measurements in the field and detect the presence of compacted layers. Ask our experts which solution is best for you.