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This paper presents the results of a geomorphological investigation of Mount Akdag landslide complex, located on the Western Taurus range, SW Turkey. The landslide, resulting in the collapse of a 5 km segment of Mount Akdag, covers an area of 9.8 km2and has a volume of about 3 × 108 m3. The 1:15,000 scale geomorphological map (Main Map) of the Akdag landslide presented here was produced from a combination of field studies and unmanned aerial vehicle-based DSM, including aerial-photo interpretation and geomorphometric analysis of landforms. The map shows contemporary and past geomorphological hillslope processes and landforms associated with the landslide complex. Our new map suggests that the Akdag landslide was a complex rockslide consisting of multiple landslide types that developed through various movements. We found that 43 highly developed and active mass movements on the main body and side slopes of the landslide made a major contribution to the sediment input. The sediment produced in the upstream severely threatens the touristic site of Saklikent Canyon in the lower catchment via an increasing magnitude of torrents. This map will provide important data for local and national administrators regarding monitoring up-to-date mass-wasting processes, understanding the landslide and its related sedimentary dynamics, and implementing risk assessment and necessary precautions. [ABSTRACT FROM PUBLISHER]

Regional land-use development projects are undertaken to protect water resources necessary for agriculture, energy and sustaining human life. The Değrmendere valley, in the province of Trabzon in the Black Sea region of Turkey, provides clean water to the city of Trabzon. The valley is part of the Silk Road from Asia to the Black Sea and contains historical monasteries such as Sumela, Kustul and Vazelon. However, over the years, misuse of the valley has caused freshwater, sea and environmental pollution. In an attempt to overcome these problems, a multilateral project, Değirmendere Vadisi Çevre Düzenlemesi (DEVA&CCedil;ED), was launched in the region. This paper aims to provide information necessary for engineering projects within the region. Six villages, on both sides of the valley, were selected for this research and evaluated in terms of river basin utilization, topography, cadastral survey of property and ownership, and land readjustment improvements. The study found illegal and improper urbanization, including industrial facilities within the valley causing water pollution. Current cadastral base maps are not sufficiently accurate for engineering projects, and in some places buildings have been constructed on unstable soils that are susceptible to landslides. The research results have helped to generate important recommendations for rehabilitation of the river basin. [ABSTRACT FROM AUTHOR]

Following a period of heavy precipitation, a large and complex mass movement, namely the Şerefiye landslide, occurred in the Black Sea region of northern Turkey on 23 June 2000. This paper describes the conditioning factors of the landslide and interprets the mass transport processes. Geology, geomorphology and tectonics were considered as the conditioning factors of the failure. Observations showed that the sloping (c.9°) area is not covered by forest trees at the crown where the motion initiated. Analysis of the hydrological response of slopes during the rainstorm indicated that the majority of the failures were caused by the development of a perched water table in the thin surface layer of clay origin, due to infiltration during heavy rain. The distance from the crown down to the toe of the landslide was measured at more than 50 m. The landslide has block sliding characteristics in the upper portions and a debris flow/soil flow component around the margins of the sliding blocks in the middle parts and at the toe. The movement was initiated near the crown as a result of the excess water content between the main formation and the clay at the end of three days of heavy rainfall. The early perturbations lasted for five to six hours, after which the central part of the zone started to move as a soil flow, in which very large intact blocks were transported. Even though the movement was very rapid (1.2 m/min), there was no loss of life. However, the movement closed the road link between Sinop and Ayancık. [ABSTRACT FROM AUTHOR]

This study examines the ripple effect on the system performance of the reverse supply chain (RSC) network and introduces a robust optimisation model for designing strong RSC networks to cope with the uncertainties caused by the ripple effect. In this manner, to the best knowledge of authors, a robust optimisation model for RSC design against the ripple effect in the context of green principles is formulated for the first time. That being the case, the study aims to provide remarkable managerial insights thanks to the developed robust optimisation model by adopting a proactive strategy before a long-term disruption occurs in the network. To this end, the robust optimisation model is applied to an industrial case study from an enterprise disassembling the household appliance. The scope of the case study is limited to the enterprise's recycling activities in the northern region of Turkey which is a potential landslide site due to the heavy rainfall. Computational experiments are performed through a set of scenarios regarding the different weight uncertainty values to reveal the changes in objective function value and decision variables. Based on the results, whilst the computationally tractable robust solutions are obtained; the price of robustness is higher than expected to protect the constraints against violation when the probability of constraint violation equals 0.01. [ABSTRACT FROM AUTHOR]

The main aim of the present study was to produce and compare landslide susceptibility maps by using five machine learning techniques, namely, artificial neural network (ANN), logistic regression (LR), support vector machine (SVM), random forest (RF) and, classification and regression tree (CART). The study area was determined as the Arhavi-Kabisre river basin, a region in which the most landslide incidents occur in Turkey. Firstly, a landslide inventory was produced by identifying a total of 252 landslides. Secondly, a total of 11 landslide conditioning factors were considered for the landslide susceptibility mapping. Subsequently, the five machine learning techniques were constructed with the help of the training dataset for the landslide susceptibility maps. Finally, the receiver operating characteristic (ROC), sensitivity, specificity, F-measure, accuracy and kappa index were applied to compare and validate the performance of the five machine learning techniques. [ABSTRACT FROM AUTHOR]

Monitoring and determining landslides in dam reservoirs is very crucial as it is one of the main factors of dam failures in the world. Coruh river basin is one of the most important river basin in the Northeast part of Turkey which accompanies five big dams. Although persistent scatterer InSAR (PSInSAR) method is a powerful remote sensing technique which can measure and monitor displacements of the Earth's surface over time, its validation is a challenging issue because of the heterogeneous PS data. In this study, the efficiency of PSInSAR is investigated by proposing two different validation methods in order to see the consistency of the determined mean deformation velocities obtained with series of Sentinel-1A SAR-images. In the first method, 3D coordinates of reference points are projected to 1D displacement values in line of sight direction and then compared with the radar displacements of PS points. In the second method, new displacement values of PS points around reference points are identified from an interpolation map in order to be compared with the original displacements of reference points. In the end, it is showed that the displacements found by PSInSAR method are consistent with the reference points' displacements measured in the study area. Finally, this work's specific objectives are to present solutions to the challenging validation problem, to show the effectiveness of PSInSAR method and to describe the remaining challenges in PS analysis of landslide applications in dam areas. [ABSTRACT FROM AUTHOR]

The use of geophysical methods, particularly ground-penetrating radar (GPR), in the environmental sites has taken very important approximation in locating potential environmental hazards such as landslides and cavities. Generally, slices of a three-dimensional (3D) GPR data set can be used to monitor changes in the surface locations and depth of the environmental hazards through the iterative slices. The aim of this study is to introduce volume imaging of subsurface cavities with a transparent half bird's-eye view within a 3D data set. Transparency is obtained by a constructed opaque function of the amplitude–colour range. The half bird's-eye view is achieved by observing angles of the x-, y- and z-directions to the 3D block. A GPR study was conducted at a reservoir area (696 m × 100 m) in Akkopru dam and hydroelectric power station in Mugla (Turkey) to determine the existence and abundance of karstic cavities. The study revealed the presence of 283 cavities of various size and depth. Borehole data encouraged the results with given depths. [ABSTRACT FROM AUTHOR]