2D-singular spectrum analysis (2D-SSA) DEM analysis VARI Web of Science Wood’s criteria applied geomorphology base-level lowering bibliometric mapping contour-felled log debris dam removal erosion evaluation feature extraction flat bed geomorphons hyperspectral image land restoration landscape changes landscape evolution landscape formation loess-like soil log erosion barrier mud forest multibeam n/a scour pit self-organization map soil erosion southern Italy spatial analysis