Energy and agrotechnical indicators in the testing of machine-tractor units with subsoiler
The present-day agriculture involves anthropogenic effects on the soil, including the compaction and over compaction of soil horizons at depths up to 1.2 m. The plowing of the soil with moldboard plows to a depth of 0.3 m results in the formation of a plow pan (hardpan), which hampers the development of plant roots; the optimum soil density for most agricultural crops is ? = 1.1-1.3 t/m3. There are supporters and opponents of deep subsoil plowing; only the plow horizon is the main object of studies. Chisel tools (subsoilers) have been studied on modernized models, which ensure the deep non-moldboard loosening to a depth of 0.30-0.45 m and more (down to 0.8 m) with the use of straight or slant shanks. Shank cultivators developed by the Siberian Research Institute of Mechanization and Electrification of Agriculture (SibIME), which penetrate to 0.30 m, were first used to control deflation. The American slant-shank subsoiler (Trade name, ‘Paraplow’) is the prototype of chisel implements. A range of tillage tools has been developed to form a ridged furrow bottom due to soil breakdown. Modernized tillage tools include breasts mounted on shanks for turning the upper (loosened) soil layer up to 0.20 m thick, as well as blades for cutting weeds, ridges, etc. Chisel modifications are mainly aimed at expanding their functional capabilities and decreasing the energy intensity of soil cultivation. The tests have confirmed the decrease of C, N, and humus losses; the improvement of the water and air conditions in the soil; the prevention of erosion; the improvement of tillage quality parameters; the increase of tractor aggregate output; and the saving of up to 25% of motor fuel.