Assessment of the application rates of liquid manure sub-soil injection

Abstract

The subsoil injection of liquid manure in large application rates (up to 100 t/ha and above) using a chisel subsoiler with a hose system increases soil fertility and is environmentally safe. A chisel subsoiler can be equipped with fi ve or six chisel tools with fl at-cut openers (small, with a working width of 325 mm and large 800 mm) with a width of tine spacing in the transverse direction of 890 and 680 mm, respectively. The depth of the chisel tools is 20 to 40 cm. The operating speed of the unit is 0.7 to 1.4 m/s. To assess the possible amount of applied liquid manure, the authors have obtained a mathematical model determining the application rate of fertilizers depending on the design and technological parameters (the geometry and installation depth of chisel tools of various widths in the tool settings, the unit speed) and soil properties. It has been established that in the range of operating speeds of 0.5 to 0.8 m/s, the maximum application rate of liquid manure for a subsoiler with fi ve working tools with openings 0.8 m wide is 80 to 90 t/ha, with six working tools – 110 to 120 t/ha. The research results show that various options for the unit settings provide for the application of liquid manure at a rate of 40 to 120 t/ha in accordance with agrotechnical requirements and environmental friendliness of the technology.