Morphometric Analysis and Evolutionary Implications of Badland Basins in Southern Italy

This study introduces the Badland Dissection Index (BDI), a new morphometric parameter that quantifies the internal dissection and drainage maturity of badland basins. The index was applied to 87 calanchi basins developed on marine clays in the Ionian sector of Basilicata (southern Italy). BDI values range from 0.13 to 0.62, with approximately 65% of the basins exhibiting values lower than 0.30, indicating mature geomorphic stages dominated by organized fluvial incision. Pearson correlation analysis shows that BDI is strongly correlated with compactness and shape indices (r = −0.71 with circularity ratio, r = 0.74 with Gravelius compactness index, GCI), and moderately with relief (r = 0.46 with Melton ratio), highlighting the primary control exerted by basin geometry on badland dissection. A principal component analysis shows that compactness-related variables and BDI dominate the first component, which explains 38.6% of the variance, while hydrological indices define an independent second component; together the first two components account for 57.4% of total variance. A multiple regression model confirms GCI as the dominant predictor of BDI (R2 = 0.58), with relief variables playing a secondary role. Owing to its simplicity, limited data requirements and clear geomorphic meaning, BDI provides a robust and scalable tool for comparing badland morphodynamics across semiarid settings and for monitoring landscape evolution where only medium-resolution topographic data are available.