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While the geomorphological elements are shaped by various dynamic processes, the involvement of human beings in this process has led to changes in different dimensions and led to the emergence of the concept of anthropogenic geomorphology. In this study, anthropogenic geomorphology elements can be observed with different factors in Istanbul-Atasehir district, the old and new topographic data compared with the Geographical Information Systems (GIS) and different anthropogenic units that play a role in this change is investigated. In this study, a systematic method consisting of several stages was used to determine relief change and anthropogenic effect factors. Land use status and changing conditions in Ataşehir were determined by satellite images, and relief changes were analyzed and compared in three different stages over the digital elevation model of the past and present. At the end of the study, most of the relief change analyzes determined were subjected to correlation analysis with anthropogenic factor units and sub-parameters and the relationship between them was explained. As a result of the research, 29% of the districts were observed to have relief changes, and according to different analyzes, the topographic surface was re-arranged at many points of the land at micro and macro scale.

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Geomorphological elements developed and changed by the influence of many dynamic processes and factors have begun to gain different dimensions and appearances under the influence of human activities. The fact that humanity has become a direct and indirect effective actor in many interventions on relief has led to the development of anthropogenic geomorphology. In this study, the anthropogenic geomorphology of the Dilderesi Basin, located within the boundaries of Kocaeli province, was investigated. In this research, a multi-step systematic was applied with the geographical perspective by using Remote Sensing (RS) and Geographic Information Systems (GIS) and different analysis and evaluation methods were tried. First of all, land use and changes occurred in the basin in 1985, 2000 and 2019 were determined. Afterwards, anthropogeomorphology map of the basin was created by considering the anthropogenic geomorphology systematics of different researchers, quantitative data were produced, analyzed and evaluated. The geological, geomorphological and hydrographic conditions in the areas where the anthropogenic pressure is intense are analyzed again and the reasons of the distribution are questioned. In order to obtain quantitative and more accurate data of relief change in the basin, over 500 points were determined in the field, satellite images, observation and measurements in field studies and effect-change map were produced. Based on many geographical elements of Dilderesi Basin, three different anthropogenic geomorphology impact scenarios have been produced with analytical hierarchy process within the scope of different impact values. As a result of the studies, it has been observed that land use changes have been experienced in the Dilderesi Basin from the past to the present day, and especially the anthropogenic geomorphology conditions in the south and west of the basin cause changes and effects on the topographic appearance. In addition, it was found that the biggest changes in relief were in quarries, main transportation routes and industrial areas and these areas affected the natural conditions of the basin by changing the topography. [ABSTRACT FROM AUTHOR]

In the last decade increasing popularity of winter tourism in mountain areas in Poland influenced development of ski infrastructure. This type of human activity may induce changes in mountain relief. The purpose of the study was to quantify ongoing change patterns via: (i) a determination of spatial and quantitative changes in catchment covered by new ski runs, (ii) a determination of the effect of new ski runs on the rejuvenation of relief in valleys adjacent to ski runs, (iii) an identification of changes in the surface runoff pattern before and after the construction of ski runs. The research was carried out in the Remiaszów catchment on two ski runs (southern Poland). Airborne Laser Scanning (ALS) data from 2013 and 2016 were also used in the study along with Terrestrial Laser Scanning (TLS) data from 2015. LiDAR (Light Detection and Ranging) point clouds were interpolated to create multi-temporal DEMs and then these DEMs were used to derive DoDs. These were used to identify erosion and accumulation zones. The Convergence Index (CI) was used to determine the direction of surface runoff. The largest changes in relief were observed in areas with ski runs, with ski run E lowering an average of 0.07 m (±0.03 m), and ski run N an average of 0.12 m (±0.03 m). The entire area lowered about 0.02 m. The construction of new ski runs resulted in a rejuvenation of denudation valleys located in the vicinity of existing ski runs. Valley incisions reaching 1.5 m (±0.15 m) were observed. Both the convergence and divergence zones for surface runoff were identified, which made it possible to show changes in the geometry of flow direction. The identification of these sites may help forecast erosion and deposition zones. In general, this may make it easier to identify areas substantially susceptible to relief change. [ABSTRACT FROM AUTHOR]

Abstract: Glaciers and rivers control the shape of the high relief topography of mountain ranges. However, their relative contribution in response to climatic oscillations and tectonic forcing and whether landscapes can reach equilibrium conditions during the Quaternary are still unclear. Here we introduce a new thermochronometer of exceptionally low closure temperature (ca. 30–35°C) based on Optically Stimulated Luminescence (OSL) dating and illustrate how it may be used to measure relief evolution and exhumation rates within the last glacial cycle in the Southern Alps of New Zealand, one of the most tectonically active orogens and an area that has experienced rapid, high magnitude climate changes. We find that exhumation rates have remained steady over the last glacial cycle and match rates observed at a million year timescale. This suggests that, despite an extreme exhumation rate of the order of 800m in 100ka, and the fact that in the last ca. 11–18ka most hillslope sides have changed from U to V-shape valleys and have been dissected by debris-flows, landslides and rock avalanches, the mean exhumation rates have remained nearly constant. This may imply that tectonics, not climate, has a primary control on the rates of exhumation in tectonically active and wet mountain belts. On the contrary, tectonically active mountain ranges might not attain equilibrium on similar timescales in weathering and/or transport limited landscapes as, for example, in arid regions. [ABSTRACT FROM AUTHOR]

Abstract: We determine to what extent low-temperature thermochronology data, in particular from age-elevation profiles, provide independent and quantitative estimates on denudation rates and relief development. Thermochronological age-elevation profiles have been widely used to infer exhumation histories. However, their interpretation has remained inherently one-dimensional, neglecting potential effects of lateral offsets between samples. Furthermore, the potential effects of transient topography on crustal isotherms and consequently on thermochronological data have not yet been addressed in detail. We investigate this problem with the aim of deriving independent estimates of both denudation rates and relief history from low-temperature thermochronometers, measuring the relative uncertainties on these parameters and finally constraining the timing of potential variations in denudation rate and/or relief development. We adopt a non-linear inversion method combining the three-dimensional thermal-kinematic model Pecube, which predicts thermal histories and thermochronological ages from an input denudation and relief history, with an inversion scheme based on the Neighbourhood Algorithm. We use synthetic data predicted from imposed denudation and relief histories and quantitatively assess the resolution of thermochronological data collected along an age-elevation profile. Our results show that apatite fission-track (AFT) ages alone do not provide sufficient quantitative information to independently constrain denudation and relief histories. Multiple thermochronometers (apatite (U–Th)/He (AHe) ages and/or track-length measurements combined with AFT ages) are generally successful in constraining denudation rates and timing of rate changes, the optimum combination of thermochronometers varying with the input scenario (relief change or varying denudation rates). However, relief changes can only be quantified and precisely constrained from thermochronological age-elevation profiles if the rate of relief growth is at least 2–3 times higher than the background denudation rate. This limited resolution is due to the depth of the closure isotherm (between ∼70 and 110°C) for the AFT and AHe systems, which only partly record topographic change. New thermochronometers (such as 4He/3He or OSL) that are sensitive to lower temperatures may be the key for resolving this issue. [Copyright &y& Elsevier]