Cultivation indicators
Tillage operations: Tillage operations include the cultivation practices conducted by the various tillage implements such as mouldboard, chisel, duck foot chisel, harrow, etc. The various tillage implements cause various erosion rates. For example a tandem disk may be more erosive than a mouldboard plough operation because it translocates more soil with greater variability throughout the landscape. The chisel plough may be equally erosive as the mouldboard plough. Large aggressive tillage implements, operating at excessive depths and speeds are more erosive than conventional ones. The tillage operations are defining after contacting the land owner. The following tillage operations can be distinguished: no tillage, plowing, disking, harrowing, and cultivator operation.
Frequency of tillage: The frequency of tillage is defined as the number of tillage operations per year conducted by the farmer. The frequency of tillage operations are defining after contacting the land owner. The following classes are used: no tillage, tillage once per year, tillage twice per year, tillage three times per year, and tillage four times per year.
Tillage depth: Tillage depth corresponds to the depth that a tillage implement such as mouldboard plough, cultivator, chisel plough, harrow etc. is disturbing the soil. The deeper the soil is ploughed the greater the soil displacement in the direction of tillage. Tillage depth is defined by conducting the land user or the extension services of the related institutes. Also plough depth can be easily measured in the field by digging the upper soil layer and measuring the depth in which tillage implements reach. The following classes are defined: (a) shallow, tillage depth <20 cm; (b) moderate deep, tillage depth 20-30 cm; (c) deep, tillage depth 30-40 cm; and (d) very deep, tillage depth >40 cm.
Tillage direction: The soil can be tilled in various directions parallel or perpendicular to the contour lines or in oblique lines depending on the slope gradient, the farm size and farm shape. The various cultivation practices such as tillage direction, direction of furrow reversion, and plough depth have variable effect on soil displacement. By ploughing the soil at shallow depth in any direction of tillage operation, tillage erosion was significantly reduced. When the physiographic conditions allowed the movement of tractor along the contour lines, then soil displacement is highly restricted. Any other direction of tillage operation increases tillage erosion. If the plough layer is moved to the up slope position under any tillage operation, then soil displacement could be considered as an operation for restoring and conserving hilly degraded areas. In hilly areas with steep slopes, where contour farming is impossible, then the soil can be ploughed perpendicular or in oblique lines but ploughing the soil at shallow depth and moving preferably the plough layer to the up slope direction. The following categories of tillage direction are distinguished: downslope, upslope, parallel to contour upslope furrow, parallel to contour downslope furrow, downslope oblique, and upslope oblique. Tillage direction can be defined by conducting the land owner or by identified in the field by observing the furrow lines.
Mechanization index: It is defined as the motor vehicles, machinery and plant used by the agricultural holding expressed in terms of horsepower (HP) per hectare of the Utilised Agricultural Area. The indicator gives a measure of how agricultural activities contribute to physical soil degradation. According to the Eurostat Glossary the following categories of machineries are distinguished: (a) Four-wheeled tractors, track-laying tractors, tool carriers, (b) Cultivators, hoeing machines, rotary hoes, motor mowers, (c) combine harvesters, and (d) other fully mechanized harvesters. Utilised Agricultural Area (UAA) is the sum of Arable Land, kitchen gardens, permanent pasture and meadow, permanent crops (Eurostat). For calculation of mechanization index each tractor, cultivator, and piece of machinery is the ratio of the total horsepower (HP) divided by the hectares of UAA.
