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IntroductionAnalysis of drainage systems and landforms along active faults provides important insights into fault evolution and present-day tectonic activity. Numerous field and laboratory studies have been conducted to examine how drainage systems evolve along strike-slip faults, uplifting blocks, and evolving thrusts and folds (

In this research work, a multi-index-based support vector machine (SVM) classification approach has been proposed to determine the complex and morphologically heterogeneous land cover/use (LCU) patterns of cities, with a special focus on separating bare lands and built-up regions, using Istanbul, Turkey as the main study region, and Ankara and Konya (in Turkey) as the independent test regions. The multi-index approach was constructed using three-band combinations of spectral indices, where each index represents one of the three major land cover categories, green areas, water bodies, and built-up regions. Additionally, a shortwave infrared-based index, the Normalized Difference Tillage Index (NDTI), was proposed as an alternative to existing built-up indices. All possible index combinations and the original ten-band Sentinel-2A image were classified with the SVM algorithm, to map seven LCU classes, and an accuracy assessment was performed to determine the multi-index combination that provided the highest performance. The SVM classification results revealed that the multi-index combination of the normalized difference tillage index (NDTI), the red-edge-based normalized vegetation index (NDVIre), and the modified normalized difference water index (MNDWI) improved the mapping accuracy of the heterogeneous urban areas and provided an effective separation of bare land from built-up areas. This combination showed an outstanding overall performance with a 93% accuracy and a 0.91 kappa value for all LCU classes. The results of the test regions provided similar findings and the same index combination clearly outperformed the other approaches, with 92% accuracy and a 0.90 kappa value for Ankara, and an 84% accuracy and a 0.79 kappa value for Konya. The multi-index combination of the normalized difference built-up index (NDBI), the NDVIre, and the MNDWI, ranked second in the assessment, with similar accuracies to that of the ten-band image classification.

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10The complex multi-directional interactions between hydrological, biological and fluvial processes govern the formation and evolution of river landscapes. In this context, as key geomorphological agents, riparian trees are particularly important in trapping sediment and constructing distinct landforms, which subsequently evolve to larger ones. The primary objective of this paper is to experimentally investigate the scour/deposition patterns around different forms of individual vegetation elements. Flume experiments were conducted in which the scour patterns around different representative forms of individual in-stream obstructions (solid cylinder, hexagonal array of circular cylinders, several forms of emergent and submerged vegetation) were monitored by means of a high-resolution laser scanner. The three dimensional scour geometry around the simulated vegetation elements was quantified and discussed based on the introduced dimensionless morphometric characteristics. The findings reveal that the intact vegetation forms generated two elongated scour holes at the downstream with a pronounced ridge. For the impermeable form of the plant, the scour got localized, more deposition was detected within the monitoring zone, and the distance between the obstruction and deposition zone became shorter. It is also shown that with the effect of bending and the subsequent decrease of the projected area of the plant and the increase of bulk volume, the characteristic scour values decrease compared to the intact version, and the scour zone obtains a more elongated form and expands in the downstream direction.