Geomorphometric characteristics of major badland landscapes of Turkey

Badlands are unique landscapes that are extensively developed on unconsolidated sediments or poorly consolidated bedrocks that are covered by little or no vegetation. They are widely observed landscapes in Turkey similar to arid and semi-arid regions of the world. Turkish badlands are commonly formed on Miocene and Plio-Quaternary deposits, especially in the inner parts of Anatolia. Additionally, these erosional landscapes are also characteristic in the volcanic provinces of Central Anatolia and Eastern Anatolia. Unlike the cognatic badland landscapes in the different arid and semi-arid sections of the world, we have very limited information about the geomorphological characteristics of Turkish badlands.

In this study, we present results from a quantitative analysis of a new inventory of badland areas (~756 km²) at six major badland landscapes in Turkey. Previously partly known but not documented badland geomorphological units were expanded by mapping badland forms from aerial photos and high-resolution multispectral image interpretations focused on the Western and Central Anatolia. The geomorphometric data on badland units, associated structures, and catchment characteristics were extracted from a 5-m Digital Elevation Model (DEM) and compiled in a GIS environment. In total 53 badland geomorphologic units, having a size from 0.15 to 89.2 km², were analyzed by comparing their topographic dissection, roughness, texture, channel density, slope height and curvature, and lithological variations to characterize their morphology further.

The regional comparison results display statistically significant topographic differences concerning their proportions of morphometric classes. The geomorphometric regional comparisons indicate that the standard deviation and modal values of slope height, topographic dissection, roughness, and curvature vary with a significant fraction in badlands formed in the terrigenous clastic and volcano-sedimentary lithological units. Moreover, the geomorphometric comparison results demonstrate that the skewness of the standard deviation of elevation and hillslope steepness varies in badland landscapes across the semi-arid Western and arid Central Anatolia, and further point out the significance of climatic conditions (i.e., amount of rainfall and evaporation) on geomorphic diversities.