Historical contingency in fluviokarst landscape evolution

摘要: Abstract Lateral and vertical erosion at meander bends in the Kentucky River gorge area has created a series of strath terraces on interior incised bends. These represent chronosequence fluviokarst landscape evolution from youngest valley side transition zone near bottom to oldest upland surface. This five-part (not including active river channel floodplain) was analyzed terms landforms that occur each stage or include dolines, uvalas, karst valleys, pocket unincised channels, cliffs (smaller features such as swallets shafts also occur). Landform coincidence analysis shows higher indices (CI) than would be expected based an idealized chronosequence. CI values indicate genetic relationships (common causality) among some unexpected persistence older surfaces. The two observed chronosequences were represented graphs using algebraic graph theory. field sites yielded more complex with less historical contingency sequence. Indeed, spectral measures for closely approximate purely hypothetical no-historical-contingency benchmark graph. deviations observations expectations, high levels complexity both point potential transitions landform types being dominant phenomenon, rather canalization along particular evolutionary pathway. As base level fluvial is lowered meanders expand, denudation are rejuvenated, remain active.