Tillage erosion is a form of soil erosion occurring in cultivated fields due to the movement of soil by tillage. There is growing evidence that tillage erosion is a major soil erosion process in agricultural lands, surpassing water and wind erosion in many fields all around the world, especially on sloping and hilly lands. A signature spatial pattern of soil erosion shown in many water erosion handbooks and pamphlets, the eroded hilltops, is actually caused by tillage erosion as water erosion mainly causes soil losses in the midslope and lowerslope segments of a slope, not the hilltops. Tillage erosion results in soil degradation, which can lead to significant reduction in crop yield and, therefore, economic losses for the farm.

Conceptually, the process of tillage erosion (E_Ti) can be described as a function of tillage erosivity (ET) and landscape erodibility (EL):

E_Ti = f(ET, EL)

Tillage erosivity (ET) is defined as the propensity of a tillage operation, or a sequence of operations, to erode soil and is affected by the design and operation of the tillage implement (e.g., the size, arrangement and shape of tillage tools, tillage speed and depth). Landscape erodibility (EL) is defined as the propensity of a landscape to be eroded by tillage and is affected by the landscape topography (e.g., slope gradient and slope curvature) and soil properties (e.g., texture, structure, bulk density and soil moisture content).

Tillage erosion occurs as a result of changes in tillage translocation (soil movement by tillage) across the field. Tillage translocation is expressed as a linear function of slope gradient (θ) and slope curvature (φ):

T_M = α + β θ + γ φ

where T_M is tillage translocation; α is the tillage translocation on flat soil surface; β and γ are coefficients which describe the additional translocation resulting from slope gradient and slope curvature, respectively. Tillage erosion, which is the net tillage translocation, is then calculated as:

T_M^Net = ΔT_M = β Δθ + γ Δφ