Flow convergence and deceleration (controlled by horizontal (kh) and vertical (kv) curvatures, correspondingly) result in accumulation of substances at soils caused by slowing down or termination of overland and intrasoil transport. The intensity of these processes and the spatial distribution of accumulated substances can depend on the spatial distribution of the following landform elements:
· Elements characterised both by convergence and by deceleration of flow - both by kh < 0 and by kv < 0 (accumulation zones)
· Elements offering both divergence and acceleration of flow: both kh > 0 and kv > 0 (dissipation zones)
· Elements that are free of a concurrent action of flow convergence and deceleration as well as flow divergence and acceleration; that is, values of kh and kv have different signs or are zero (transit zones)
Classification of landform elements by signs of kh and kv
Accumulation, transit and dissipation zones are revealed by registration of kh and kv maps, or using digital models of accumulation (Ka) and mean (H) curvatures. Negative values of Ka correspond to transit zones, while positive values of Ka correspond to both accumulation and dissipation zones. Accumulation and dissipation zones are distinguished using values of H. Positive values of Ka with negative values of H correspond to accumulation zones, whereas positive values of Ka with positive values of H correspond to dissipation zones.
For details and examples, see: