Analysis of soil compaction induced beneath the working depth due to tilling action of different active tillage machinery

Aim of study: To quantify the data regarding soil compaction induced beneath the tillage working depth purely due to the tilling action of the different active tillage machinery in sandy loam soil. Area of study: Research Farm, CCS Haryana Agricultural University, Hisar, Haryana, India Material and methods: The data were quantified in terms of cone index (CI), bulk density, and porosity. Its comparison was also made with conventional practice followed by the farmers, involving only passive-tillage tools (i.e. cultivator and disc harrow). The results did not represent the tractor-imposed soil compaction under the tires. Main results: The maximum soil compaction beneath the working depth in terms of increment in soil CI occurred with rotavator followed by conventional practice, PTO-operated disc tiller, and power harrow, which are in the range of 6.67-7.05%, 5.17-5.29%, 4.29-4.97%, and 2.08-2.36%, respectively. The increment in bulk density was similar to that as mentioned above with values in the range of 3.96-4.06%, 2.30-2.42%, 1.71-1.88%, and 1.31-1.40%, respectively. Furthermore, the maximum decrement in soil porosity occurred with rotavator followed by conventional practice, PTO-operated disc tiller, and power harrow which were in the range of 5.67-6.61%, 2.74-2.94%, 1.71-1.88%, and 2.06-2.25%, respectively. Research highlights: The active tillage rotary machinery cause soil compaction due to the applied compressive force on the soil during their tilling action. They create optimal topsoil tilth but can compact deeper soil due to blade speed, necessitating the selection of ideal rotational and forward speeds to minimize this compaction.