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A coordinated multi-year ocean exploration campaign on the Blake Plateau offshore of the southeastern U.S. has mapped what appears to be the most expansive cold-water coral (CWC) mound province thus far discovered. Nearly continuous CWC mound features span an area up to 500 km long and 110 km wide, with a core area of high-density mounds up to 254 km long by 42 km wide. This study synthesized bathymetric data from 31 multibeam sonar mapping surveys and generated a standardized geomorphic classification of the region in order to delineate and quantify CWC mound habitats and compare mound morphologies among subregions of the coral province. Based on the multibeam bathymetry, a total of 83,908 individual peak features were delineated, providing the first estimate of the overall number of potential CWC mounds mapped in the region to date. Five geomorphic landform classes were mapped and quantified: peaks (411 km2), valleys (3598 km2), ridges (3642 km2), slopes (23,082 km2), and flats (102,848 km2). The complex geomorphology of eight subregions was described qualitatively with geomorphic “fingerprints” (spatial patterns) and quantitatively by measurements of mound density and vertical relief. This study demonstrated the value of applying an objective automated terrain segmentation and classification approach to geomorphic characterization of a highly complex CWC mound province. Manual delineation of these features in a consistent repeatable way with a comparable level of detail would not have been possible.

Diatomite deposits of the lacustrine Truckee Formation near Hazen, Northern Nevada, are of Miocene age (ca. 10.3 million years old) and consist of varved deposits within commercial mines. These exposed deposits have been primary source of paleontological samples of stickleback fish fossils (Gasterosteous doryssus) spanning 100,000 years. These samples have revealed stasis, rapid morphological and genetic evolution, and local extinction of G. doryssus against a background of changing diatom communities. Here, we draw on geological, limnological, anthropogenic, and bibliographical data to illustrate the geographic and paleontological context of the Hazen diatomite deposits. We include a stratigraphic section describing lithology and stickleback specimen frequency at a 1 mm resolution. This paper should help researchers identify patterns in fossil site distribution and better understand the geological processes that have shaped the area, spurring new sampling and future research.

The article focuses on challenging the validity of geomorphic markers and dating methods used in a previous study of fault slip rates along the Magallanes Fault System in Tierra del Fuego, Patagonia. It critiques the suitability of the markers selected and the robustness of the dating techniques applied, arguing that the conclusions drawn from the original study may be unreliable due to these methodological issues.

The border river of the Evros/Meriç/Maritsa has been shaped during the century since its demarcation by the Lausanne peace treaty. Over this period, a dense overlap of environmental, geopolitical, legal and cultural actors has turned it into both a riverised border and a borderised river. The border regime appropriates the riverine characteristics of flow, erosion, mud, turbulence and fog as much as it is founded on military technology, international law, agricultural and conservation practices, resource logistics, border crossing and the denial thereof. Here, the river's movement of sand and alluvium has become an agent in the policing of the river border. Drawing on interviews with asylum seekers, locals, forensic pathologists, legal scholars and fish scientists, this paper weaves field research, primarily undertaken on the Greek side, with a historic and ecosystemic perspective of a century‐old border that has become a hotspot for violent practices. These practices themselves harness the uncertain physical conditions that the riverscape affords. In this article we argue that the disjunctures of the river's dynamic geomorphology and the history of demarcation of the median line frame the contemporary politics of mobility of those illegalised by the border regime. In the ambiguous territorial pockets produced by the movement of the river away from the median line of 1926, islands of hyperlegality have been produced where state violence takes place with impunity. [ABSTRACT FROM AUTHOR]

SUMMARY: The Pohang Basin sustained the most extensive seismic damage in the history of instrumental recording in Korea due to the 2017 Mw 5.5 earthquake. The pattern of damage shows marked differences from a radial distribution, suggesting important contributions by local site effects. Our understanding of these site effects and their role in generating seismic damage within the study area remains incomplete, which indicates the need for a thorough exploration of subsurface information, including the thickness of soil to bedrock and basin geometry, in the Pohang Basin. We measured the depth to bedrock in the Pohang Basin using dense ambient noise measurements conducted at 698 sites. We propose a model of basin geometry based on depths and dominant frequencies derived from the horizontal-to-vertical spectral ratio (HVSR) of microtremor at 698 sites. Most microseismic measurements exhibit one or more clear HVSR peak(s), implying one or more strong impedance contrast(s), which are presumed to represent the interface between the basement and overlying basin-fill sediments at each measurement site. The ambient seismic noise induces resonance at frequencies as low as 0.32 Hz. The relationship between resonance frequency and bedrock depth was derived using data from 27 boreholes to convert the dominant frequencies measured at stations adjacent to the boreholes into corresponding depths to the strong impedance contrast. The relationship was then applied to the dominant frequencies to estimate the depth to bedrock over the whole study area. Maps of resonance frequency and the corresponding depth to bedrock for the study area show that the greatest depths to bedrock are in the coastal area. The maps also reveal lower fundamental frequencies in the area west of the Gokgang Fault. The results indicate a more complex basin structure than previously proposed based on a limited number of direct borehole observations and surface geology. The maps and associated profiles across different parts of the study area show pronounced changes in bedrock depth near inferred blind faults proposed in previous studies, suggesting that maps of bedrock depth based on the HVSR method can be used to infer previously unknown features, including concealed or blind faults that are not observed at the surface. [ABSTRACT FROM AUTHOR]

Agricultural land cover in the U.S. Midwest is a major source of nutrient pollution that has led to impairment of stream water quality. This study examines the impact of a forested state park on nutrient concentrations within an agriculturally dominated watershed. Water samples were collected over a 2‐year study period from eight stream sampling sites along four creeks and processed for total nitrogen (TN), nitrate (NO3−‐N), total phosphorus (TP), and orthophosphate (PO43−‐P). Hydrology, channel morphology, and remotely sensed land cover and vegetation data were also collected and analyzed within the study area. Results indicate that water quality responses to a forested state park vary between TN, NO3−‐N, TP, and PO43−‐P, and water quality variables are uniquely influenced by watershed and stream characteristics. The greatest water quality benefits most frequently occurred within the two smallest study streams with the greatest residence times and proportion of watershed areas within the forested state park. Overall, the greatest improvements to water quality occurred during periods of low stream discharge and when riparian vegetation was greenest. The results of this study suggest that conservation of forested areas within agriculturally dominated watersheds can provide water quality improvements in the U.S. Midwest. Targeting watersheds that drain small streams with long residence times for conservation may be most beneficial to improving water quality. [ABSTRACT FROM AUTHOR]

The present study aims to examine the changing hydro-geomorphological properties of the Mayurakshi River located in a plateau fringe region in Jharkhand and West Bengal. The field investigation of 14 cross-sectional sites has been conducted during the post-monsoon season of 2021 to determine important geomorphic parameters such as channel depth, width, bank height, hydraulic radius, and wetted perimeter. Post-processed kinematic survey and electromagnetic current meter tool have been used to measure the river bed profile and channel velocity, respectively, to obtain more accurate locational information. The primary objective of this study is to compare field-observed discharge data with the discharge volume predicted by a few hydraulic and hydrological models in order to determine the models that are best suited for further application in a scientifically accepted and cost-effective manner. The results demonstrate that there is a noticeable rise in flow velocity from upstream (0.22 m/s) to downstream of the river (0.85 m/s), which is also supported by the results of Manning's equation and kinematic wave parameter. The most correct relationship is then presented by minimizing the deviations between the calculated and analytical discharges at three separate stages. The results show that the proposed Manning's technique is quite accurate with the observed data, as determined by the mean absolute percentage error (60.16%), root mean square error (30.53%), and normalized root mean square error (0.05) indices. [ABSTRACT FROM AUTHOR]

Copyright of Natural Gas Geoscience is the property of Natural Gas Geoscience and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Natural Gas Geoscience is the property of Natural Gas Geoscience and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Natural Gas Geoscience is the property of Natural Gas Geoscience and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The electrical transport of saturated porous rocks has been studied in 3-dimensions for five different channel geometries. The five selected geometries can form the de-constructed parts of any real transport channel in reservoir rocks. The average cross-sectional area and effective length of each of the channels have been computed to construct the geometric factor. The electrical properties studied showed a quadratic increase with increase in clay fraction in the channel with surface conductivity emerging as the major contributor responsible for conductivity at clay fraction ∼ 0.5 and above. The role of clay conductance in electrical transport was investigated for the different geometries. Variations in pore throat size corresponded to non-linear shifts in effective conductivity with clay conductance, in contrast to the linear increase observed for uniform pore throat size. Channel structures with inverse gradients in flow paths, showed significantly lower electrical conductivity. Structures with more than one parallel path displayed higher electrical conductivity. [ABSTRACT FROM AUTHOR]

The battering of bedrock by bedload collisions is the primary mechanism by which bedrock rivers erode and landscapes evolve. The energy imparted via impacts acts to detach bedrock via the growth and intersection of surface fractures. We present impact experiments designed to test the influence of particle impact energy on bedrock erosion rates. We found that erosional efficiency increased with increasing impact energy. Notably, these increases in efficiency are not captured by a widely‐used mechanistic bedrock erosion model. Observed increases in erosional efficiency were linked with enhanced elastic energy dissipation captured by differences in the coefficient of restitution. We suggest that this increase in energy dissipation is indicative of enhanced crack extension for high velocity impacts. Our experiments indicate a clear energy‐dependence for bedrock detachment processes that is not yet captured by bedrock incision models but may be integrated into long‐term erosion rates and landscape evolution. Plain Language Summary: Bouncing sediment grains batter the bedrock beds of rivers during floods. As these impacts collide with the bed, they slowly chip away at the riverbed bedrock. It's perhaps intuitive that a grain with more energy when it collides with the riverbed is able to chip away more bedrock. But, how much more destructive are these high energy impacts? We designed an experiment where we hit a bedrock sample with a steel ball at a range of impact energies, over and over again, up to 30,000 times, and measured how much material was chipped away. High energy impacts eroded more material, but this increased efficiency of erosion is not fully captured by impact‐based erosion models. We hypothesize that for higher energy impacts, a larger fraction of the incoming energy is used to crack the bedrock, more easily eroding material. We liken the relative influence of these high energy impacts to a battering ram, where only a few strikes can easily break down a door, whereas lower energy impacts, similar to a simple knock, are unlikely to achieve the same result. We suggest that this effect may be important in determining the influence of extreme events on bedrock erosion over long timescales. Key Points: Impact experiments demonstrate that bedrock erosional efficiency is enhanced with increasing impact energyExperimentally‐derived coefficients of restitution and rock resistance coefficients indicate enhanced elastic energy dissipation with increasing impact energyResults suggest that more energetic impacts enhance crack extension, increasing erosional efficiency [ABSTRACT FROM AUTHOR]

The recognizable shapes of landforms arise from processes such as erosion by wind or water currents. However, explaining the physical origin of natural structures is challenging due to the coupled evolution of complex flow fields and three-dimensional (3D) topographies. We investigate these issues in a laboratory setting inspired by yardangs, which are raised, elongate formations whose characteristic shape suggests erosion of heterogeneous material by directional flows. We combine experiments and simulations to test an origin hypothesis involving a harder or less erodible inclusion embedded in an outcropping of softer material. Optical scans of clay objects fixed within flowing water reveal a transformation from a featureless mound to a yardang-like form resembling a lion in repose. Phase-field simulations reproduce similar shape dynamics and show their dependence on the erodibility contrast and flow strength. Through visualizations of the flow fields and analysis of the local erosion rate, we identify effects associated with flow funneling and the turbulent wake that are responsible for carving the unique geometrical features. This highly 3D scouring process produces complex shapes from simple and commonplace starting conditions and is thus a candidate explanation for natural yardangs. The methods introduced here should be generally useful for geomorphological problems and especially those for which material heterogeneity is a primary factor. [ABSTRACT FROM AUTHOR]

Monitoring of compensatory stream mitigation projects conventionally relies on spatially discrete geometric data and habitat assessments collected from representative reaches. Project success is evaluated by extrapolating site‐scale metrics such as rapid bioassessment protocol (RBP) scores and time‐series changes in width‐to‐depth ratios to adjacent reaches. For example, an excellent RBP score at one location is used to infer excellent habitat in nearby reaches. This paper compares spatially discrete and continuous monitoring data from 38 km of restored stream length on a stream mitigation project in central Kentucky to document how conventional site‐level metrics may not represent conditions in adjacent reaches, particularly on projects plagued by post‐construction geomorphic instability (e.g., headcut migration, propagation of bank erosion, and chute cutoff formation). Over a 5‐year monitoring period, rapid visual assessment walkabouts documented project‐scale geomorphic process trajectories that were not captured by conventional site‐specific monitoring. Early detection of geomorphic instability from this rapid monitoring approach facilitated cost‐effective and tailored adaptive management (e.g., planting of live stakes to arrest bank erosion). Full‐census walkabouts can thereby help to improve mitigation credit valuation, enhance long‐term habitat protection, and facilitate successful steam restoration outcomes. [ABSTRACT FROM AUTHOR]

We analyse 498 faults identified in satellite imagery and interpret the height and width of associated footwall ranges with respect to co‐seismic elastic rebound from tectonic and erosional unloading. The dynamics of footwall uplift link uplands to catchment patterns and interrelated hanging wall sedimentary fans. Height–length relations of some catchments and associated alluvial fans scale linearly whereas others, such as fault‐slope catchments and related down‐fault fans (building out from faults) show a significant scatter without an obvious trend. Perched basins abandoned in the footwalls of younger faults offer catchment‐fan height–length relations like watergap and dipslope‐related fans and, besides, hint at reduction of dip angle due to rollback of larger faults before abandonment. Analysis of the width‐to‐height ratio (W/h) of footwall ranges offer a robust linear statistical trend, h = 0.06 W and is identical between datasets. This trend is valid for both arid and tropical rifts, the latter offering smaller rebounds. Contributions of elastic rebound on fault throw in our data are simplistically considered through comparison to global trends on fault length versus throw. This allows consideration around maximum throw (Tmax) linked to the maximum height of footwall ranges (h) and to their width (W) above the reference level. Basic calculations indicate that co‐seismic rebound contributes from <1% to 17% of extensional fault throw. Width‐to‐height ratios for large faults (L > c. 50 km) show less spread than smaller faults. Such large faults expectedly dissect the brittle crust, indicating that these large faults which root in the ductile–brittle transition approach a balanced, steady‐state kinematic pattern. We speculate that significant crustal thinning associated with these large faults triggers the onset of isostatic adjustments that drive fault rotation, instigating fault abandonment and disconnected perched basins. [ABSTRACT FROM AUTHOR]

We present the geophysical data set acquired in summer 2022 close to Ny-Ålesund (western Svalbard, Brøggerhalvøya Peninsula, Norway) as part of the project ICEtoFLUX. The aim of the investigation is to characterize the role of groundwater flow through the active layer as well as through and/or below the permafrost. The data set is composed of electrical resistivity tomography (ERT) and ground-penetrating radar (GPR) surveys, which are well-known geophysical techniques for the characterization of glacial and hydrological processes and features. Overall, 18 ERT profiles and 10 GPR lines were acquired, for a total surveyed length of 9.3 km. The data have been organized in a consistent repository that includes both raw and processed (filtered) data. Some representative examples of 2D models of the subsurface are provided, that is, 2D sections of electrical resistivity (from ERT) and 2D radargrams (from GPR). The resistivity models revealed deep resistive structures, probably related to the heterogeneous permafrost, which are often interrupted by electrically conductive regions that may relate to aquifers and/or faults. The interpretation of these data can support the identification of the active layer, the occurrence of spatial variation in soil conditions at depth, and the presence of groundwater flow through the permafrost. To a large extent, the data set can provide new insight into the hydrological dynamics and polar and climate change studies of the Ny-Ålesund area. The data set is of major relevance because there are few geophysical data published about the Ny-Ålesund area. Moreover, these geophysical data can foster multidisciplinary scientific collaborations in the fields of hydrology, glaciology, climate, geology, and geomorphology, etc. The geophysical data are provided in a free repository and can be accessed at 10.5281/zenodo.10260056 (Pace et al., 2023). [ABSTRACT FROM AUTHOR]

In the field of coastal geomorphology, advancements in space technology have revolutionized coastal mapping and understanding. Satellite‐derived bathymetry (SDB) research has progressed, focusing on various estimation methods using high‐resolution satellite imagery and in‐situ data. Challenges arise when applying these methods to the Indian coastline due to its turbid waters and intricate features such as creeks and deltas, laden with sediment and submerged rocks. A study aims to assess multivariate machine learning (ML) regression techniques for estimating bathymetric data. The study employs ground‐truth data and imagery from Aster, Landsat‐8, and Sentinel‐2 at distinct sites known for complex underwater landscapes. Several algorithms including Multiple Linear Regression, Support Vector Regressor, Gaussian Process Regression (GPR), Decision Tree Regression, K‐Neighbors Regressor, k‐fold cross‐validation with Decision Tree Regression, and Random Forest (RF) are evaluated for SDB. Results from the Vengurla Site show that using the Landsat‐8 data set with the GPR algorithm achieves R2 0.94, root mean squared error (RMSE) 1.53 m, and MAE 1.14 m, utilizing visible spectrum bands. At Mormugao, the Sentinel‐2 data set with GPR and RF algorithms attains R2 0.97 and RMSE 1.23 m, with GPR outperforming RF, having an MAE of 1.05 m compared to RF's 1.22 m. This study underscores the potential of ML regression techniques in overcoming challenges with using SDB for mapping coastal geomorphology, particularly in intricate underwater terrains and turbid waters by assimilating sophisticated algorithms and their refined cartographic representation. Plain Language Summary: Researchers are leveraging advancements in space technology to enhance the mapping and comprehension of coastal regions, particularly focusing on satellite‐derived bathymetry (SDB). SDB utilizes high‐resolution satellite imagery in conjunction with on‐site data to estimate the submerged terrain. However, the application of these methodologies along the Indian coastline poses challenges due to factors such as turbidity and the presence of complex geological formations like creeks and deltas. This study explored the utilization of multivariate machine learning (ML) regression techniques to improve the estimation of SDB. Various algorithms were tested using data sourced from satellites such as Aster, Landsat‐8, and Sentinel‐2 across two different sites with diverse underwater landscapes. Results demonstrate promising accuracy, particularly when employing Landsat‐8 data in conjunction with Gaussian Process Regression (GPR), yielding an R2 value of 0.94. Similarly, at another site, the combination of SENTINEL‐2 data with GPR and RF achieved an R2 value of 0.97, underscoring the potential of ML techniques in mapping intricate coastal terrains despite challenges like turbid waters. Key Points: Advancements in space technology for coastal bathymetry mappingPredicting coastal geomorphology with satellite‐derived bathymetry (SDB)Multivariate machine learning regression for estimating SDB [ABSTRACT FROM AUTHOR]

High-resolution 3D seismic data analysis was integrated with a calibrated well and biostratigraphy data to present the first overview of a buried Pleistocene canyon system on the upper slope of the eastern Niger Delta, the Galabor Canyon. Attribute maps of specific horizons allow documenting the changing morphologies and infill lithologies of two main branches of the canyon through two stages of activity separated by a reference horizon dated at 0.99 Ma based on well calibration. At the upper slope, growth faults dissect the canyon heads, the catchment of which encroaches a network of valleys incised on the outer shelf. The canyon fill is composed of muddy channels and mass-transport deposits, largely derived from the collapse of canyon walls and sand-rich bodies forming a tract sourced by shelf-edge deltas at the outlet of the incised valleys. High-density turbiditic processes likely control the distribution of sand bodies along the canyon, ranging from tributary fans on the upper slope to 6 km-wide meander belts on the middle slope. The sandy deposits accumulate in minibasins formed along the canyon path, downstream of the subsiding hanging wall of the growth faults and upstream of shale ridges that damp the flow in the canyon. These results show that canyons can be major targets for sand reservoir exploration on the upper slope of large muddy deltas. [ABSTRACT FROM AUTHOR]

Detailed palaeogeographical studies of the accumulative fan in the Serteyka River valley in W Russia and underlying biogenic deposits were carried out. The base of a representative core of biogenic sediments in the distal zone is dated to 1291 BC, while its top to 1631 AD. In this paper, palynological, plant macrofossils, Chironomide and Cladocera, geochemical, geochronological and sedimentological analysis were performed. Four phases of biogenic deposition were distinguished by pollen and geochemical analyses. Two of them coincide with the climatic fluctuation during Medieval Climate Anomaly and Little Ice Age. During the formation of the fan, overbank deposits were accumulated also, indicating numerous and intense floods, which are in line with the trend observed for other sites in this region. The accumulative fan is formed by lower, middle and upper deluvia and agricultural diamicton in its top. All units have specific sedimentological and geochemical features as well as low admixture of plant macrofossils. The beginning of the formation of this relief form dates back to the second half of the 17th century AD, and the end of the accumulation falls on the second half of the 18th century AD. Our work suggests that natural conditions had an impact on the formation and development of studied accumulative fan, however, the decisive factor causing the intensification of the slope processes were related with deforestation resulted from strong human impact, which was marked in palynological and macrofossils analyses (e.g. increase in the contribution of plants macrofossils related to agriculture). [ABSTRACT FROM AUTHOR]

Early human habitation of the arid to semiarid Central Iranian Plateau was strongly connected to the availability of water and associated natural hazards, such as flooding and drought events. In this geoarchaeological study, we focus on the occupation at the prehistoric site of Ajor Pazi within the formerly active fluvial environment of the Varamin Plain. Through radiocarbon and luminescence‐dated sediment cross‐sections, we apply multivariate statistics to sedimentological characteristics of bulk samples collected during a rescue excavation in 2018. Based on facies interpretations, we differentiate depositional processes and present their implications for the environs of Ajor Pazi. Our results show evidence of settlement activities between 6.4 and 5.6 ka cal B.P. (4.4–3.6 ka cal. B.C.E.). Phases of reduced geomorphodynamics can be distinguished when soil‐forming processes take place. Our findings provide insights into the hitherto scarcely explored Transitional Chalcolithic II period during which the site of Ajor Pazi emerged and began to shape its environs. [ABSTRACT FROM AUTHOR]

We present a meta-analysis of mangrove litterfall across 58 sites in the American Pacific, exploring its variability among geoforms, ecoregions, and provinces. This study contributes to filling the information gap on litter-based primary productivity in American mangroves at the ecoregional level and directly examines the effects of geomorphological and biogeographic factors on mangrove productivity. The objective was to evaluate how geoform, ecoregion, and province factors, along with eight environmental variables, influence litterfall-based primary productivity. Each site was categorized according to its landform through the analysis of satellite images obtained from various sensors on the Google Earth Pro v. 7.3.6 platform. Additionally, it was categorized according to its ecoregion and province by analyzing the occurrence of the sites on biogeographic unit coverage in ArcMap 10.4.1. We then analyzed the effect of each factor and the efficiency of categorization using multivariate methods. Our results showed significant differences in litterfall among the geoforms, with estuaries exhibiting higher litterfall production (11.90 Mg ha−1 year−1) compared to lagoons (7.49 ± 4.13 Mg ha−1 year−1). Differences were also observed among provinces, with the highest average in the Tropical Eastern Pacific (11.19 ± 3.63 Mg ha−1 year−1) and the lowest in the Warm Temperate Northeast Pacific (7.34 ± 4.28 Mg ha−1 year−1). Allocation success analyses indicated that sites classified by dominant species and province were more predictable (>60.34%) for litterfall production. Additionally, the maximum temperature and the precipitation of the wettest month and the driest month explained 34.13% of the variability in mangrove litter-based primary productivity. We conclude that mangrove litterfall production is influenced by coastal geomorphic characteristics and biogeography, which are, in turn, affected by latitude-induced climate variation. [ABSTRACT FROM AUTHOR]

Deep learning methods paired with sidescan sonar (SSS) are commonly used in underwater search-and-rescue operations for drowning victims, wrecks, and airplanes. However, these techniques are primarily used to detect mine-like objects and are rarely applied to identifying features in dynamic dredge pit environments. In this study, we present a Sandy Point dredge pit (SPDP) dataset, in which high-resolution SSS data were collected from the west flank of the Mississippi bird-foot delta on the Louisiana inner shelf. This dataset contains a total of 385 SSS images. We then introduce a new Effective Geomorphology Classification model (EGC). Through ablation studies, we analyze the utility of transfer learning on different model architectures and the impact of data augmentations on model performance. This EGC model makes geomorphic feature identification in dredge pit environments, which requires extensive experience and professional knowledge, a quick and efficient task. The combination of SSS images and the EGC model is a cost-effective and valuable toolkit for hazard monitoring in marine dredge pit environments. The SPDP SSS image dataset, especially the feature of pit walls without a rotational slump, is also valuable for other machine learning models. [ABSTRACT FROM AUTHOR]

This study presents a comprehensive assessment of the geomorphology, crater distributions, and tectonic structures within Enceladus' cratered terrains. We analyzed the distributions of impact craters and tectonic structures in seven regions of interest to inform an interpretation of the geological history of this terrain in the context of Enceladus' global evolution. We found that the tectonic structures, including both ancient, subdued troughs and young, narrow fractures, point to a cratered terrain that not only experienced early tectonic modification but also shows evidence of recent geological activity. Ancient troughs present in the equatorial cratered terrains are similar in scale and orientation to troughs present in the Leading and Trailing Hemisphere Terrains, an observation that supports possible non‐synchronous rotation of the ice shell. A dearth of impact craters in the equatorial regions as identified previously does not hold for craters <3 km in diameter in the anti‐Saturnian hemisphere. The anomalous presence of excess small craters in this region could be due to secondary or sesquinary impacts from a catastrophic event occurring at Enceladus or a neighboring moon. Finally, narrow fractures are pervasive across the cratered terrains and are most commonly oriented parallel or sub‐parallel to the most proximal cratered terrain boundary. This directionality of pervasive recent fracturing could be related to the vertical movement of an isostatically uncompensated ice shell. Enceladus' cratered terrains provide insight into the long‐term evolution of the satellite, an important component to assessing its role in Solar System evolution and its potential for habitability. Plain Language Summary: We present a comprehensive characterization of the oldest terrain on Enceladus, the cratered terrains. We evaluated structural features and impact craters on the surface, including their morphology and spatial distributions. This analysis informs how we interpret the formation and change of these surface features in the context of how Enceladus as a whole has changed over time. We found that there are two main types of tectonic structures in the cratered terrains, including one set of relatively old troughs and at least one set of narrow fractures that is very young. This finding indicates that not only have the cratered terrains experienced early tectonic activity, but were also active recently. The ancient set of troughs are similar to those present in younger terrains on Enceladus, suggesting that the ice shell has rotated relative to its tidally locked position about Saturn. The comparatively young, narrow fractures in the cratered terrains are widespread and could have formed due to a vertically shifting ice shell. Enceladus' cratered terrains provide insight into what long‐term changes have taken place on the surface, an important component to understanding how Enceladus fits into Solar System formation and its past or present potential to host life. Key Points: Systematic review of Enceladus' cratered terrains results in a stratigraphic framework for geologic mapping and age determinationTroughs in the equatorial cratered terrains are similar to tectonized equatorial regions, suggesting non‐synchronous ice shell rotationAncient, subdued troughs and young, narrow fractures point to a cratered terrain that experienced both early and recent tectonic activity [ABSTRACT FROM AUTHOR]

Wave‐driven erosion of marsh boundaries is a major cause of marsh loss, but little research has captured the effect of seasonal differences on marsh‐edge retreat rates to illuminate temporal patterns of when the majority of this erosion is occurring. Using five surface models captured over a study year of a marsh with a steep escarped boundary in South San Francisco Bay, we find a pronounced seasonal signal, where rapid marsh retreat in the spring and summer is driven by a strong sea breeze but little change is found in the marsh‐edge position in the fall and winter. We found accretion in the mudflat transition region close to the marsh boundary in the calmer seasons however, suggesting intertwined morphodynamics of mudflats and the eroding marsh‐scarp. We observed large spatial heterogeneity in retreat rates within seasons, but less on longer (annual and decadal) timescales. The relationship between marsh‐edge retreat rates and properties of the wave field nearby is explored and contextualized against extant relationships, but our results speak to the difficulty in addressing spatial erosion/accretion variability on short (seasonal) timescales with simple models. Plain Language Summary: Waves can cause destruction of marshlands when they collide with the boundary of the marsh area. We studied how the speed of marsh loss from waves can change between seasons with different climates. To do this we made five 3D models of a marsh in South San Francisco Bay over a single year and looked at their differences between summer/fall/winter/spring. We found fast marsh loss in the seasons where daily winds are common (spring/summer), and minor changes in seasons with storms but without daily winds (fall/winter). Across our entire marsh, we saw lots of variety in how much it was changing, including some addition (i.e., positive change) to the mudflats near the marsh in the fall/winter. When we compared the marsh loss over one year to what was lost between 2004 and 2019, the speeds were similar, so we believe our study period was similar to long‐term marsh dynamics. This work encourages incorporating different seasonal climates into expectations of how marshes evolve, and supports that we need to think about marshes and mudflats as connected in how they change over time. Key Points: A unique seasonal data set exposes strong seasonality in marsh‐edge retreat, with rapid retreat during warm periods with strong sea breezeThere is large variation in retreat rates across the marsh seasonally but more uniform retreat rates on annual and decadal timescalesDigital surface models provide insight into erosion and accretion simultaneously across the marsh‐mudflat system [ABSTRACT FROM AUTHOR]

Landslides in Colombia represent a serious threat to the safety of local communities and the surrounding infrastructure, especially in the mountain range zone. These events occur due to the variation and correlation of endogenous conditions existing in each area, such as geology, geomorphology and coverage, which are triggered by rainfall, seismic events or anthropic activities. This article aims to analyze the geoenvironmental conditions between 2016 and 2021 in the sector known as Cortinas (Toledo, Colombia), applying, for this purpose, the innovative concept of "accumulated geotechnical deterioration" in order to explain the evolution of susceptibility over time from the perspective of prediction, which under traditional methodologies is not properly considered, since unlike what has been thought, the conditioning factors do change in the short and medium term, especially in tropical areas. As a result of this part of the research, the hypothesis was validated that it is necessary for the terrain to be under certain specific conditions for an instability event to occur, which does not depend only on certain critical thresholds of rainfall and earthquakes. [ABSTRACT FROM AUTHOR]

Sedimentary records of Ri-Yue Tang (Sun Moon Lake), which is the largest lake in Taiwan, provide valuable hydro-environmental information during the past 15,000 years. From the viewpoint of hydro-geomorphological conditions, the interval is roughly divided into four stages: (i) high water level with large artificial water inflow (1934 AD–present), (ii) low water level with a comparatively large catchment area (1919 AD–ca. 2800 years BP), (iii) frequent high water level with a small catchment area (ca. 2800–ca. 13,500 years BP), and (iv) low water level with a comparatively large catchment area (ca. 13,500–15,000 years BP). The changes in the conditions are mainly shown in the physical properties. A small mineral grain size and large grain density suggest enough water with high water level while large grain size and small density imply low water level and limited water discharge. Dam construction (1919–1934 AD) for more water supplies to the newly established power station greatly influences the hydro-geomorphological and environmental conditions in the Ri-Yue Tan lake-catchment system. Additional artificial water inflow with mineral material through the waterway from the Wujie Reservoir has transported more sediments (roughly twice) after the dam construction. The increase in water level due to the dam construction caused water-area enlargement and catchment-area shrinkage, resulting in changes in material production (erosion), transportation, and sedimentation in the original system. The increase in water amount supplied from the reservoir is also printed in the physical properties (small mineral grain size and large grain density) and chemical properties (organic, HCl soluble, and bi-SiO2 contents) of lacustrine sediments. [ABSTRACT FROM AUTHOR]

Egypt is a country that heavily relies on agricultural activities. River Nile serves as the primary source of irrigation water for agricultural purposes. El Saieda Basin project, located in the southern western desert of Egypt, represents a massive agricultural project where irrigation water is distributed from the River Nile through an extensive network of canals. This study focuses on evaluating the groundwater resources, the groundwater quality, and the hydrochemical processes affecting the groundwater within El Saieda Basin to provide an additional source of irrigation water and to ensure a safe water supply for the residential villages. Various data sets were integrated, including geomorphology, geology, hydrogeology, hydrogeochemistry and stable isotopes. Based on the geomorphology; the study area includes four geomorphological units, Structural Plateau, Bajada Plain, Eroded old Nubian surface, and Nile alluvial Plain. According to the geology; the study area is located in the southern part of the Western Desert. The dominating geological units in this part of Egypt range in age from Lower Cretaceous to Recent. Regarding the hydrogeology of the study area; the Quaternary aquifer is the main aquifer in the study area where 24 groundwater samples plus two surface water samples (irrigation canal + main Drain) were collected and analyzed. Groundwater salinity classification shows that 17% of the total groundwater samples are fresh groundwater samples with values that range between 550 and 996 mg/l with an average of 775 mg/l. 29% of the total groundwater samples are brackish groundwater samples with values that range between 1177 and 2273 mg/l with an average of 1868 mg/l. In addition, 46% of the total groundwater samples are salty groundwater samples with values that range between 3197 and 4886 mg/l with an average of 4037 mg/l. The rest of the groundwater samples (8%) are saline groundwater samples with a maximum value of 9018 mg/l and an average of 7645 mg/l. The groundwater's temperature ranges from 25 to 30.9 C. However, the measured pH values showed relatively neutral water where the values range from 6.6 to 7.6. The relationship between salinity content and the other ions indicates that sodium, calcium, magnesium, sulfate, and chloride are the effective ions that increase the salinity content. Silicate weathering and dissolution of calcite are the main hydrochemical processes affecting the groundwater. From the saturation indices (SI) results it is indicated that Gypsum and Anhydrite dissolve with negative SI values, whereas iron minerals are supersaturated with positive values. Carbonate minerals are insufficiently soluble in groundwater, with values that fluctuate positively and negatively around zero. From the hypothetical salts, it is indicated that the quaternary groundwater aquifer in the study area is highly evolved as it's enriched with terrestrial and marine residuals indicated by the presence of NaCl, MgCl2, MgSO4, CaSO4, Ca(HCO3)2 salts. From the Environmental Stable Isotopes, it is indicated that all the groundwater samples are enriched by 18O and Deuterium which indicates a recharge from the main irrigation canal and return flow irrigation water. Trace elements results indicated that the groundwater is suitable for human drinking according to the World Health Organization and also for irrigation according to the Australian guidelines for irrigation water quality. [ABSTRACT FROM AUTHOR]

Boulders are globally widespread and influence processes across many landscapes including hillslopes, coasts, rivers and extra‐terrestrial settings. Boulders are described as particles, sufficiently large, that they have a disproportionate effect on the surrounding landscape. Moving beyond this conceptual definition, however, requires a somewhat arbitrary decision of how to define a minimum boulder size. The implications of boulder definition on study findings are rarely considered. We investigate the suitability of five boulder definitions, two based on fixed sizes: (1) 0.26 m and (2) 1 m, and three definitions which vary based on system characteristics: (3) grain mobility, (4) grain protrusion and (5) surface grain size distribution (> 84th percentile, D84). We consider the impact of definition on calculated boulder metrics, and, for the >1m and >D84 definitions, their association with channel and catchment characteristics across 20 boulder‐bed streams in northern Sweden. We also surveyed river managers responsible for restoring these rivers, to gain a practitioner insight on boulder size definition. We found that boulder definition matters; for metrics relating to the number or density of boulders, the >D84 and >1m size definitions were negatively correlated. Surveys indicated the importance of communicating boulder definition. We conclude that, whilst the best choice of boulder size definition will vary based on the questions of interest and techniques employed, evaluating the implications of the chosen boulder size definition and communicating the reasoning behind boulder definition choice is crucial. [ABSTRACT FROM AUTHOR]

River channels, riparian and floodplain forms and dynamics are all influenced strongly by biological processes. However, the influence of macroinvertebrates on entrainment and transport of river sediments remains poorly understood. We use an energy‐based approach to explore the capacity of benthic animals to move surficial, gravel‐bed particles in field and laboratory settings and use the results to assess the relative significance of biological and physical benthic processes. Our results showed that in 11 British gravel‐bed rivers, the maximum energy content (i.e., calorific content) of macroinvertebrate communities generally matched the flow energy associated with median discharges and, at multiple sites, exceeded that of the 10‐year return interval flood. A series of laboratory experiments used to estimate the minimum energy expended by signal crayfish (Pacifastacus leniusculus) when performing geomorphic work established that crayfish move gravel particles at energy levels below that expected of the flow, complicating direct comparisons of the capacity for macroinvertebrates and fluvial flows to influence bed mobility. Our findings suggest that the influence of macroinvertebrate communities in either promoting or suppressing, the mobilisation of the bed may be large compared to equivalent values of fluvial energy. Based on these findings, we conclude that in the gravel‐bed rivers studied, the macroinvertebrate community's potential to perform geomorphic work matches or exceeds the stream power during most of the year. Although our study examined biological and fluvial energy systems separately, it is important to recognise that in nature, these systems are highly interactive. It follows that utilising the energy framework presented in this paper could lead to rapid advances in both fluvial biogeomorphology and river management and restoration. [ABSTRACT FROM AUTHOR]

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In this article, we track the evolution of fluvial biogeomorphology from the middle of the 20th century to the present. We consider the emergence of fluvial biogeomorphology as an interdisciplinary research area that integrates knowledge drawn primarily from fluvial geomorphology and plant ecology, but with inputs from hydrology and landscape ecology. We start by assembling evidence for the emergence of the field of fluvial biogeomorphology with a keyword search of the Web of Science and a detailed analysis of papers published in two scientific journals: a geomorphology journal—Earth Surface Processes and Landforms; a multidisciplinary river science journal—River Research and Applications. Based on this evidence, we identify three distinct time periods in the development of fluvial biogeomorphology: the 'early years' before 1990; the transitional decade of the 1990s; and the period of rapid expansion and diversification in themes, methods and investigation scales since 2000. Because the literature is vast, we can only summarize developments in each of these time periods, but we refer to recent in‐depth reviews and conceptual perspectives on relevant topics. Thus, rather than a full and deep review, we present an annotated bibliographic overview of the development of fluvial biogeomorphology, whereby the text describes broad trends but is supported by tables of citations that can deliver greater detail. We end with a brief consideration of likely future developments. [ABSTRACT FROM AUTHOR]

This Special Issue arose from a 1‐day international workshop on the theme of Fluvial Biogeomorphology to mark Professor Angela Gurnell's official retirement. As co‐editors, we felt this Special Issue also afforded an opportunity which we could not let pass by to capture some key aspects of Angela's inspiring and impactful career to date. We have written this Preface to accompany the main Editorial as a celebration of Angela's distinguished career and the many contributions Angela has made to physical geography and in particular fluvial geomorphology. We present an overview of Angela's career, insights into key research areas and contributions through a consideration of her publications, and her work inspiring early career researchers through PhD supervision before some final, more personal, reflections. [ABSTRACT FROM AUTHOR]

Research in fluvial biogeomorphology largely aims to promote our understanding of the interactions between riparian vegetation and fluvial morphodynamics within riverine ecosystems. Starting at the end of the last century, Angela M. Gurnell has made a major contribution to fluvial geomorphology by considering water flow and sediment transport in combinaton with riparian and later also aquatic vegetation and thus significantly promoting the fluvial biogeomorphological approach from its early days until today. The objective of the present paper is to present a set of studies and results obtained over the last 20 years mainly by the authors and many collaborators, including Angela M. Gurnell, on a panel of French rivers: the Tech, Garonne, Isère and Allier. In particular, feedback mechanisms between fluvial morphodynamics and riparian vegetation dynamics were investigated directly in the field and by using high‐resolution remote sensor systems at the scale of individual plants, populations, communities and landscapes as well as during semi‐controlled ex‐situ experiments at the scale of individual plants. Collectively, the authors' research conducted over the past 20 years has helped to elucidate some key aspects of the feedback dynamics between the lowest and highest levels of the riparian ecosystem organization. This article reviews and discusses those key aspects. The gradually obtained results have contributed to a better understanding and quantification of feedback between river morphodynamics and vegetation at nested spatiotemporal scales, from plant species traits to the riverine landscape. Furthermore, the biogeomorphological approach advocated for more than 20 years now has clearly facilitated the extension of the discipline of geomorphology to ecology in general and evolutionary ecology in particular and thus contributed to a more integrative vision of earth surface processes. [ABSTRACT FROM AUTHOR]

During the Late Holocene, the majority of lowland river systems in temperate Europe transformed from low‐energy multi‐channel rivers in strongly vegetated marshy floodplains to more open floodplains characterised by single‐channel meandering rivers with overbank deposits. While the general framework of this transformation in floodplain geomorphology, ecology and hydrology (i.e. geoecohydrology) is widely recognised many uncertainties remain as its timing varies significantly, both among different river catchments and within them. To unravel whether the observed differences in floodplain response can be attributed to differences in the timing and nature of the driving forces or to a difference in sensitivity towards them, we compare long‐term and large‐scale reconstructions of the geoecohydrological floodplain dynamics and of the (climatically and anthropogenically driven) land cover change for two contrasting regions: the central Belgian loess belt and the sandy Campine region. By using a combination of cluster analysis, ordination and Ellenberg indicator scores on a large multi‐proxy and multi‐site dataset, we revealed the major trends in the past geoecohydrological evolution of northeastern Belgian floodplains. These trends are probably determined by changes in floodplain wetness, which can in turn be linked to variations in upland forest cover. The Early and Late Holocene floodplain transformations appear synchronous with the respective increases and decreases in upland forest cover in the vicinity of the sites, largely determining the water availability in the river catchments and thereby their local geoecohydrological conditions. Initially, these evolutions were determined by climate, but during the Middle and especially Late Holocene anthropogenic influence became a far more important factor, causing the evolutions in the two studied regions to increasingly diverge. While marshy floodplains with forested margins can still be found in the sandy Campine region today, these have become rare in the central Belgian loess belt due to the combination of a higher level of human impact and greater erodibility of the soils in this area. Despite the strong spatiotemporal variability of the floodplain transformations, we observe a trend towards increasingly rapid floodplain responses to upland land cover changes over the course of the Holocene, probably related to the growing hillslope–floodplain connectivity. We conclude that the (dis)similarities in Holocene geoecohydrological floodplain change can be largely attributed to the (dis)similarities in (climatically or anthropogenically driven) land cover change in the uplands, although the differences in inherent sensitivity of the locations – linked to factors such as soil type and topography – further complicate the already non‐linear impact–response relationships. [ABSTRACT FROM AUTHOR]

Source‐to‐sink transfer of sediment and organic carbon (OC) is regulated by river mobility. Quantifying trends in river mobility is, however, challenging due to diverse planform morphologies (e.g., meandering, braided) and measurement methods. Here, we utilize a remote‐sensing method applicable to all planform morphologies to quantify the mobility timescales of 80 rivers worldwide. Results show that, across the continuum from meandering to braided rivers, there is a systematic reduction in the timescales of channel mobility and—to a lesser extent—floodplain reworking. This leads to a decrease in the efficiency with which braided rivers rework old floodplain material compared to their meandering counterparts. Reduced floodplain reworking efficiency of braided rivers leads to smaller channel‐belt areas relative to their size. Results suggest that river‐mobility timescales derived from remote sensing can aid in the characterization of sediment and OC storage and transit times at a global scale. Plain Language Summary: Rivers transport sediment and organic carbon (OC) from the mountains to the sea, and river movement affects sediment and OC transit times in landscapes. Understanding the controls on timescales of river movement is critical for assessing how fluvial processes influence the terrestrial carbon cycle. While previous work has quantified different river planform shapes on the Earth's surface (e.g., meandering, wandering, and braided), little is known about how the pace and nature of river movement is different between river planform shapes. This is because we lack methods to measure and compare river movement across different river planform shapes. Here, we leverage a tool to quantify river movement from time series of satellite imagery that is equally applicable to all river planform shapes. We apply this method to calculate the timescales of river movement of 80 rivers worldwide for the last 37 years. We show that (a) braided rivers migrate faster than meandering rivers, and (b) braided rivers move over a smaller area relative to their size. Comparing results with geochemical observations from the Río Bermejo—a well‐studied river for sediment‐OC cycling—we show that our mobility framework may provide a new way to assess sediment and OC storage timescales in floodplains. Key Points: We quantify timescales of floodplain reworking and channel‐overlap decay from satellite imagery of 80 rivers worldwideFrom meandering to braided planform morphology, there is a reduction in the overlap timescale and the reworking timescaleMobility timescales provide a means for remotely quantifying terrestrial‐sediment and organic‐carbon storage and transit [ABSTRACT FROM AUTHOR]

Fish assemblages, defined by taxonomy or functional traits, –respond to regional and local habitat variation. Our hypothesis was that fish assemblages could be best predicted using reach‐scale (RS) hydrology variables over valley‐scale (VS) hydrogeomorphology variables for US and Mongolian rivers. We further predicted that fish traits were predicted better by RS than VS variables. We evaluated the FS and VS hydrogeomorphologies of rivers in the United States and Mongolia in each of three ecoregions: grassland, forest and endorheic. Fishes were collected using a backpack electrofisher, following standard protocols. Constrained ordination analyses were conducted at three scales: among continents, by continents and by individual ecoregions within continents. We found no significant difference in mean variation explained by VS versus RS or by taxonomy versus traits. Ecoregions differed in factors contributing to fish assemblage patterns, likely a result of differences in hydrogeomorphology, hydrological connectivity and historical influences. We found that fish assemblages were structured by hydrogeomorphic processes occurring at VS and RS, and that variables predicting fish assemblages varied with scale and whether fishes were classified by taxonomy or traits. Although anthropogenic impacts were substantially higher for western US rivers than for Mongolian rivers, we were unable to detect strong differences in our ability to predict fish assemblage variation from RS and VS habitat variables. [ABSTRACT FROM AUTHOR]

The upper catchment of the Claro river is located within the Transitional Southern Volcanic Zone in the Maule Region of Chile (35.5°S), at the foothills of Manantial Pelado volcano, a Pleistocene stratovolcano whose morphology suggests the occurrence of important glacial processes in the area. The observed glacial landforms can be sequenced and associated with episodes of volcanic activity. Different units of volcanic and glacial origin were identified based on field observations, detailed mapping, and digital elevation model and satellite image analysis. The contact relations between them made it possible to discern four events that can be linked to Marine Isotope Stages 8, 6, 4‐2, and to the Neoglacial. We propose seven stages in the geomorphological evolution from the late Pleistocene to the late Holocene, where there is coexistence between volcanic and glacial episodes, such as the emplacement of the Manantial Pelado volcano overlying the Abanico and Cola de Zorro formations; a subsequent debris avalanche; the enlargement of the Del Indio valley during the Penultimate Glaciation; the construction of Cerro Redondo (a minor eruptive center at the head of Del Indio valley); ongoing fluvial incision; and Neoglacial advances. The relative chronology proposed in this work contributes to clarifying the Pleistocene–Holocene geomorphological history in this catchment and to further understand the interplay between volcanic and glacial processes in the central Chilean Andes during the Quaternary. [ABSTRACT FROM AUTHOR]

Precipitation has a fundamental influence on landscape evolution and erosion rates. Accurate predictions of precipitation changes are crucial for landscape evolution modelling and erosion modelling. The Tianshan Mountains are known as the 'Water Tower in Central Asia', where precipitation is the main water supply for the surrounding lakes and rivers and also supports the population and economic development in the plain areas. This study developed a global climate model (GCM) and digital elevation model (DEM)‐based downscaling method and simulated high‐resolution monthly precipitation in Tianshan from 2000 to 2050, with a resolution of 90 m. The datasets developed from 30 surface observation stations had a high degree of precision and simulated the precipitation processes well in the historical period. The simulation results indicated that precipitation will increase at a rate of 11 mm/decade under the SSP245 scenario and 5 mm/decade under the RCP4.5 scenario from 2022 to 2050. Spatially, precipitation was projected to increase in the central and eastern regions and decrease in the western region. In the Kaidu, Urumqi and Manas river basins in the central Tianshan Mountains, precipitation was projected to increase at a rate of 20 mm/decade. The datasets developed here have important theoretical and practical implications for water resource management, and sustainable development in Central Asia. [ABSTRACT FROM AUTHOR]

The crop-land suitability assessment (LSA) is important for managing land and water resources and developing sustainable agricultural systems. In the field of determining the suitability of cropland, the multi-criteria evaluation approach (MCEA) or multi-criteria decision-making (MCDM) is becoming more popular as a tool for analyzing difficult situations and obtaining logical conclusions. The 75 relevant publications from 2010 to 2023 were reviewed and summarized in this paper to precisely explain and identify MCEA application areas and decision-making problems resolved within the crop-land suitability assessment. The findings indicated that the MCDM or MCEA techniques have been applied with or without remote sensing, Agricultural Land Use Evaluation System, parametric methods, etc. for land suitability evaluation. This study also contributes to the classification of criteria used for this purpose. A total of 117 parameters from six groups: soil properties, climate, topography, hydro-geomorphology, land use compatibility, and hazard are necessary for LSA. [ABSTRACT FROM AUTHOR]

Terrain feature points, such as peaks, pits, and saddles, represent the macro-structure of the landform. Conventional techniques for extracting these points from digital elevation models (DEMs) often grapple with issues of inaccuracy, omission and redundancy, largely due to the problematic necessity of setting threshold values. This paper proposes an innovative approach for the automatic detection of terrain feature points based on the topological relationships of contours and the inherent constraints of terrain shape characteristics. The study provides a robust mathematical model of terrain feature points and an effective algorithm for their extraction. Comparing with manually reference data, the accuracy metrics including completeness, correctness, and quality of our extracted results demonstrate a high level, significantly surpassing those obtained through existing algorithms. This proposed approach not only avoids the spurious feature points produced by the local window method, but also prevents the omission of valid points and the creation of redundant ones. Moreover, by utilizing the contour interval as its only variable, our approach eliminates the need for various threshold settings, streamlining the extraction process. [ABSTRACT FROM AUTHOR]

The northwest-trending Altai Mountains of central Asia expose a complex network of thrust and strike-slip faults that are key features accommodating intracontinental crustal shortening related to the Cenozoic India-Asia collision. In this study, we investigated the Quaternary slip history of the Fuyun fault, a right-lateral strike-slip fault bounding the southwestern margin of the Altai Mountains, through geologic mapping, geomorphic surveying, and optically stimulated luminescence (OSL) geochronology. At the Kuoyibagaer site, the Fuyun fault displaces three generations of Pleistocene– Holocene fill-cut river terraces (i.e., T3, T2, and T1) containing landslide and debris-flow deposits. The right-lateral offsets are magnified by erosion of terrace risers, suggesting that river course migration has been faster than slip along the Fuyun fault. The highest Tp2 terrace was abandoned in the middle Pleistocene (150.4 ± 8.1 ka uppermost OSL age) and was displaced 145.5 +45.6/–12.1 m along the Fuyun fault, yielding a slip rate of 1.0 +0.4/–0.1 mm/yr since the middle Pleistocene. The lower Tp1 terrace was abandoned in the late Pleistocene and aggraded by landslides and debris flows in the latest Pleistocene–Holocene (36.7 ± 1.6 ka uppermost OSL age). Tp1 was displaced 67.5 +14.2/–6.1 m along the Fuyun fault, yielding a slip rate of 1.8 +0.5/–0.2 mm/yr since the late Pleistocene. Our preferred minimum slip rate of ~1 mm/yr suggests the Fuyun fault accommodates ~16% of the average geodetic velocity of ~6 mm/yr across the Altai Mountains. Integration of our new Fuyun slip rate with other published fault slip rates accounts for ~4.2 mm/yr of convergence across the Chinese Altai, or ~70% of the geodetic velocity field. [ABSTRACT FROM AUTHOR]

The 1605 M7½ Earthquake is the only earthquake in the history of China that has caused large-scale land subsidence into the sea, with the total area of land subsidence exceeding 100 km2. The disaster has led to the sinking of 72 villages. There is still no clear understanding of the source seismogenic fault of this earthquake. In this work, we conducted a detailed study of the middle segment of the Maniao-Puqian fault (MPF), which is the epicenter area, through geomorphological survey, data collection, shallow seismic exploration, cross-section drilling, and chronological dating. The results showed that the middle segment of the MPF zone is composed of three nearly parallel normal faults with a dextral strike-slip: "Macun-Luodou fault (F2-1), Haixiu-Dongyuan fault (F2-2), and Changliu-Zhuxihe fault (F2-3)". And F2-2 is composed of two secondary faults, namely F2-2′ and F2-2″, with a flower-shaped structure buried under the ground. It is distributed nearly east-west, dipping to the north and has experienced at least five stages of activities since the Miocene. The vertical activity rates of F2-2′ and F2-2″ are ∼2.32 and ∼2.5 mm/a, since the Holocene, respectively. There were eight cycles of transgression and regression since the Miocene. The fault activity resulted in the thickening of the Holocene strata with a slight dip to the south, on the hanging wall, showing V-shaped characteristics. The MPF is likely the source seismogenic fault of the M7½ earthquake that hit Qiongshan in 1605. [ABSTRACT FROM AUTHOR]

I argue that the dynamic nature of contemporary, landscape‐shaping (geomorphic) processes deserves more consideration in conservation science and practice. In an analysis of a sample of fundamental terms related to geomorphology and area‐based conservation in the Web of Science, I found that the terms co‐occurred in <2% of the analyzed entries (titles, abstracts, and keywords) from 2000 to 2020. This result is indicative of the rather peripheral attention that, more broadly, landscape‐shaping processes seem to receive in the conservation literature. Among conservation scientists and practitioners, landforms that define the physical structure of habitat are often perceived as largely static, whereas the consideration of their dynamic adjustments to geomorphic processes is often limited to extreme events. I use examples derived from river‐floodplain environments to illustrate strong, multifaceted, and reciprocal interactions between biota and various erosional and depositional processes. These ubiquitous interdependencies clearly demonstrate that geomorphic processes are an integral part of ecosystem dynamics at time scales relevant for conservation. Crucially, erosional and depositional processes modulate many environmental impacts of past and current anthropogenic activities. I conclude that the absence of a more explicit and widespread consideration of geomorphic processes in conservation science and practice is surprising and detrimental to their effectiveness. I call for bolstered efforts among the conservation and geoscience communities to better integrate landscape dynamics within the field of conservation. The rise of the ecosystem‐based and social‐ecological systems approaches to conservation and the growth of interdisciplinary geoscience branches (e.g., biogeomorphology, ecohydraulics, and geoconservation) will facilitate such an integration. [ABSTRACT FROM AUTHOR]

Coastal zones are highly dynamic and constantly influenced by geomorphological and physical properties. Thus, estimating coastal vulnerability around the world is necessary for coastal zone management. Makran region, in the southeast of Iran, with a 133 km coastline, is considered a case study for vulnerability analysis and estimating its potential for further economic developments. The coastal vulnerability index (CVI) was considered with five parameters: geomorphology, regional elevation, coastal slope, shoreline changes and mean significant wave height. Significant wave height is an additional variable we added to CVI estimation compared to previous works. MIKE 21 software was used to extract this variable. Seven images from the Landsat satellite were employed to provide shoreline transformation. According to our results 52% of the coastline is ranked as high-vulnerability index, and 15% as very-high vulnerability index. We detected some anthropogenic areas with considerable accretion along the shoreline, while these areas were not considered vulnerable areas according to CVI. Thus, we reckon a sort of shortcoming in calculating CVI for not giving weight to the variables involved. This aim to be achieved necessitates organized historical research over the area, which was out of the scope of this sole research. Research highlights: Inclusive employment of geomorphic and hydrodynamic parameters is suggested for calculating CVI. However, a shortcoming in this calculation is the lack of information to give weight to the variables involved. More than half of Makran shoreline (67%) is ranked as high to very high-vulnerable area, which means specific concern is needed for any further anthropogenic activities around this area. Accretion can be counted as an issue on CZM, specifically on the area with anthropogenic activities, such as ports. [ABSTRACT FROM AUTHOR]

Fishing-down-marine-food-webs has resulted in alarming declines of various species worldwide. Benthic rays are one examples of such overexploited species. On tidal flats, these rays are highly abundant and play an ecologically important role. They use tidal flats as refuge, feeding and resting grounds, during which they bury into the sediment, which results in sediment bioturbation. Changes in bioturbation intensity, following ray removal, may affect the biogeomorphology of tidal flats with possible cascading effects on the macrozoobenthic community. However, it is poorly understood how these indirect effects could influence ecosystem function. We therefore studied the geomorphic impact of benthic rays (specifically the pearl whipray/stingray Fontitrygon margaritella) on the tropical tidal flats of the Bijagós Archipelago, Guinea-Bissau, on a landscape scale. We investigated 1) bioturbation rates by rays using drone and ground surveys, 2) the spatial distribution of ray pits on multiple tidal flats, 3) the impact of rays on sediment properties and macrozoobenthos by experimental exclusion (15 months). Benthic rays bioturbated 3.7 ± 0.35% of the tidal flat's sediment surface per day over one single 24-h period, which equals a complete top-sediment-surface turnover every 27 days. The spatial distribution of ray pits was affected by tidal flat geomorphology since pits decayed faster at areas exposed to strong hydrodynamic forces. Predator exclusion altered sediment properties, leading to changes in sedimentation (− 17%) and erosion (− 43%) rates. In addition, macrozoobenthic species composition changed, marked by an increase in Capitellidae worms and a greater biomass of Malacostraca over time. These changes indicated substantial effects of ray bioturbation on the biotic and geomorphic landscape of tidal flats. Overall, we conclude that changing abundances of benthic rays can have clear landscape-wide geomorphological effects on intertidal ecosystems. These indirect consequences of fisheries should be incorporated in integrative management plans to preserve tidal flats and connected ecosystems. [ABSTRACT FROM AUTHOR]

The occurrence of subsurface karst caves can cause the development of superficial depressions which, in turn, may pose a construction hazard. Identifying such a substratum requires integrated non-invasive measurement methods. The main objective of the study was to demonstrate the effectiveness of the non-invasive ERT, TLS, and GPR survey techniques in identifying the karst floor and determining the direction of discontinuities around the cave. The paper analyzes the limitations of the methods used in the study of heterogeneous media. These limitations are related to the methodology and measurement conditions, data processing, and interpretation in the context of the resolution and depth range. The study was conducted using the example of the Jaskinia pod Świecami cave, formed in the Sarmatianal calcarenites in Poland. The research confirmed its complex karst-anthropogenic genesis. The cave was formed as a result of the infiltration of rainwater and the dissolution of limestone by groundwater, while the paleokarst forms that are characteristic of it and of the surrounding caves and occur in their vicinity, i.e., narrow ridges called "karst candles", were formed as a result of water circulation during the local permafrost degradation in the middle Pleistocene. However, these forms were modified in the Upper Pleistocene and Holocene, as indicated by ERT images. [ABSTRACT FROM AUTHOR]

The Rodl-Kaplice-Blanice fault system (RKB) of Variscan shear origin, repeatedly active since the Late Paleozoic to the Recent, is expressed by a number of lithological contacts, distinct geophysical gradients and many landforms. A general trend of the RKB as well as linear configuration of its internal architecture is fairly similar to those of topical near Rhine Graben and Alpine-Carpathian transition area as the two other consistent recently reactivated large-scale tectonic structures in the extended (thinned) crust of central Europe. In middle part of the RKB, the occurring linear topographic and geological features parallel to the main RKB sections point to the existence of a wide tectonic zone in the crust following the fault system. Our multidisciplinary study includes a summary of corresponding basic geological data, overview of seismic, regional geophysical and geomorphological conditions, primary model of recent kinematic activity in the RKB area derived from the space (Global Navigation Satellite System—GNSS) monitoring and terrestrial (repeated high precision levelling) geodetic data and comparison of these various information. The obtained knowledge indicates that the RKB is active up to ~ 1.0 mm horizontally and > 0.5 mm vertically. The fault system area in the Bohemian Massif can be subdivided into the three parts of diverse tectonic structure and block kinematics. Sinistral horizontal movements are highest near the southern surface sections (Rodl-Kaplice, Rudolfov and Drahotěšice faults), whereas noticeable vertical differentiation is going on mainly along the Blanice and Kouřim faults in the north where the RKB activity is gradually decreasing towards the extensive Elbe shear zone with transverse movements. The middle part of the RKB is dislocated by a large active transverse tectonic structure of the South Bohemian Basins (SBB) with variable horizontal velocity vectors of surface GNSS stations. Most of the weak regional earthquakes have been recorded west of the RKB. Besides faults of the SBB, these were mainly associated with the RKB-subparallel Lhenice fault. Based on the earthquake distribution and foci depths, the latter fault can have similar structural position as the RKB related to lower part of the Variscan level in the ~ 10–12 km depth. [ABSTRACT FROM AUTHOR]

Hydrogeomorphology studies river dynamics, focusing on the interactions between flow structure, sediment transport, and the morphologies that characterize rivers and their watersheds. It provides an analytical framework and tools for better integrating knowledge of river dynamics into river management in the broadest sense, and more specifically, into river restoration as well as into the assessment and prevention of risks associated with fluvial hazards. In Quebec, hydrogeomorphology is emerging as a significant contribution to risk assessment and management approaches, and is at the heart of a paradigm shift in river management whereby process restoration aims to increase the resilience of fluvial systems and societies, and improve the quality of fluvial environments. This contribution outlines the trajectory of hydrogeomorphology in Quebec, based on scientific publications by Quebec geographers, and discusses the discipline's aims in research and knowledge integration for river management. Messages clés: Les géographes du Québec ont contribué fortement au développement des connaissances et outils de l'hydrogéomorphologie.L'hydrogéomorphologie a évolué d'une science fondamentale à une science où les connaissances fondamentales sont au service de la gestion des cours d'eau.L'hydrogéomorphologie et le cortège de connaissances et d'outils qu'elle promeut font de cette discipline une partenaire clé pour une gestion holistique des cours d'eau. [ABSTRACT FROM AUTHOR]