Expanding implementation of an on-line measurement system of topsoil compaction in loamy sand, loam, silt loam and silt soils.

A previously developed model for on-line prediction of soil compaction indicated as bulk density (BD), was limited in use for a sandy loam field. This study was undertaken to investigate the possibility of modifying this model for new soil textures, namely loamy sand, loam, silt loam and silt soils. Using the on-line measurement system of BD, measurements were carried out in four fields with different average textures of loam, sandy loam and silt loam and silt loam/silt fields. The on-line measurement system used consisted of a subsoiler, whom draught (D) was measured with a single shear beam load cell and depth (d) was measured with a wheel gauge consisted of a swinging arm metal wheel equipped with a linear variable differential transducer (LVDT). The soil gravimetric moisture content (MC) was measured with the oven drying method. The on-line measured BD was compared with measured BD with Kopecki rings (core sampling method) (736 samples), to validate the potential use of this sensor in the new studied soil textures.