Journal of Geophysical Research: Earth Surface最新文献

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Barchans Interacting With Dune-Size Obstacles: Details of the Fluid Flow and Motion of Grains Barchans与沙丘大小的障碍物相互作用:流体流动和颗粒运动的细节
IF 3.5 2区 地球科学
Journal of Geophysical Research: Earth Surface Pub Date : 2025-06-12 DOI: 10.1029/2025JF008504
N. C. Lima, W. R. Assis, D. S. Borges, E. M. Franklin
{"title":"Barchans Interacting With Dune-Size Obstacles: Details of the Fluid Flow and Motion of Grains","authors":"N. C. Lima,&nbsp;W. R. Assis,&nbsp;D. S. Borges,&nbsp;E. M. Franklin","doi":"10.1029/2025JF008504","DOIUrl":"https://doi.org/10.1029/2025JF008504","url":null,"abstract":"<p>We investigate details of the interaction of subaqueous barchans with dune-size obstacles by carrying out numerical simulations where the fluid is solved at the grain scale and the motions of individual grains are computed at all time steps. With the outputs, we analyze the disturbances of the fluid flow, the trajectories of grains, and the resultant force on each grain, the latter being unfeasible from experiments and field measurements. We show that in some cases particles pass over the obstacle, while in others they completely circumvent it (without touching it), or are even blocked. For the circumvention and blocking cases, which we call bypass and trapped, respectively, we show the existence of a strong vortex between the lee face of the dune and the obstacle. This vortex results from the interactions of recirculation regions and horseshoe vortices, and has enough strength to deviate the main flow and carry grains around the obstacle in those cases. Our results shed light on the reasons for passing over, circumventing, and blocking, and contribute to our understanding of dunes in the presence of large obstacles such as hills, crater rims, and human constructions.</p>","PeriodicalId":15887,"journal":{"name":"Journal of Geophysical Research: Earth Surface","volume":"130 6","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2025JF008504","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144264488","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Coherent Motion of Channel Threads in the Braided Brahmaputra-Jamuna River 辫状布拉马普特拉-贾穆纳河河道线的相干运动
IF 3.5 2区 地球科学
Journal of Geophysical Research: Earth Surface Pub Date : 2025-06-10 DOI: 10.1029/2024JF008196
Yuan Li, Ajay B. Limaye
{"title":"Coherent Motion of Channel Threads in the Braided Brahmaputra-Jamuna River","authors":"Yuan Li,&nbsp;Ajay B. Limaye","doi":"10.1029/2024JF008196","DOIUrl":"https://doi.org/10.1029/2024JF008196","url":null,"abstract":"<p>Braided river channels are formed by multiple channel threads that often shift laterally through either abrupt avulsion or more coherent migration over time. Several approaches have been developed to quantify the planform change of braided rivers, but predicting this change remains challenging due to the intricate structure of the channel network and the strong sensitivity of planform morphology to water stage. To address these challenges, we developed an approach to test whether individual channel threads move laterally across annual timescales. We then test whether a curvature-driven model for the migration of meandering rivers can similarly explain the motion of braided channel threads. As a case study, we analyze the migration pattern of the Brahmaputra-Jamuna River, whose discharge is strongly seasonal due to the monsoonal hydroclimate. We characterize planform morphology by selecting low-stage water masks derived from Landsat images. We find that from 2001 to 2021, ∼43% of the total length of channel threads migrated coherently, at an average rate equivalent to ∼30% of the local width of the channel thread per year. Migration rate is weakly related to channel-thread width. In three examples, the migration rate is closely related to the channel-thread curvature, and the curvature-driven model successfully describes their migration. By connecting the motion of channel threads with their planform geometry, the analysis suggests that the seemingly chaotic motion of braided rivers is somewhat organized over decadal timescales, indicating the potential for better hazard and flood predictions for communities living within and along these river channels.</p>","PeriodicalId":15887,"journal":{"name":"Journal of Geophysical Research: Earth Surface","volume":"130 6","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JF008196","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144244586","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Experimental Investigation of the Effect of Wave-Current Interactions on the Morphology and Dynamics of Subaqueous Dunes 波流相互作用对水下沙丘形态和动力学影响的实验研究
IF 3.5 2区 地球科学
Journal of Geophysical Research: Earth Surface Pub Date : 2025-06-10 DOI: 10.1029/2023JF007623
I. Abroug, P. Weill, N. Abcha
{"title":"Experimental Investigation of the Effect of Wave-Current Interactions on the Morphology and Dynamics of Subaqueous Dunes","authors":"I. Abroug,&nbsp;P. Weill,&nbsp;N. Abcha","doi":"10.1029/2023JF007623","DOIUrl":"https://doi.org/10.1029/2023JF007623","url":null,"abstract":"<p>Dunes in natural marine environments are subject to various complex and unsteady hydrodynamic forcings. In shallow waters and intertidal environments in particular, subaqueous dunes are strongly influenced by waves which combine with unidirectional or reversing currents. Understanding and predicting their morphology and dynamics is crucial because bedform-related roughness strongly influences sediment transport. In this article, we investigate in a flume tank the impact of monochromatic waves combined with a unidirectional current on the geometry of migrating dunes as well as the associated flow field. The influence of the wave steepness and dispersion on the bathymetry temporal evolution, the streamwise velocity, the vertical velocity, the turbulence intensity, and Reynolds shear stress above migrating dunes were examined. Furthermore, higher order moments related to the streamwise velocity were calculated in order to evaluate the flow non-Gaussian behavior above migrating dunes. Our experiments confirm that the presence of migrating dunes can produce non-Gaussian statistics related to the streamwise velocity. The skewness and the kurtosis of the horizontal velocity have different trends. Skewness has a local maximum on the top of the stoss shallower region of the dune, whereas the kurtosis has a local maximum on the dune's lee side.</p>","PeriodicalId":15887,"journal":{"name":"Journal of Geophysical Research: Earth Surface","volume":"130 6","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144244587","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Initiation of Sediment Resuspension by Combined Wave-Current Conditions in an Artificial Seagrass Meadow 波流复合条件下人工海草草甸沉积物再悬浮的启动
IF 3.5 2区 地球科学
Journal of Geophysical Research: Earth Surface Pub Date : 2025-06-08 DOI: 10.1029/2024JF008050
Chuyan Zhao, Heidi Nepf
{"title":"Initiation of Sediment Resuspension by Combined Wave-Current Conditions in an Artificial Seagrass Meadow","authors":"Chuyan Zhao,&nbsp;Heidi Nepf","doi":"10.1029/2024JF008050","DOIUrl":"https://doi.org/10.1029/2024JF008050","url":null,"abstract":"<p>Laboratory experiments examined the impact of current on ripple formation and the onset of wave-driven resuspension within an artificial seagrass meadow modeled after <i>Zostera marina.</i> Within the meadow, the current was less than or equal to the wave velocity. Meadows were constructed with three shoot densities: 247, 455 and 962 stems/m<sup>2</sup>, and each shoot had six flexible blades. The sediment bed, consisting of <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mn>65</mn>\u0000 <mspace></mspace>\u0000 <mi>μ</mi>\u0000 <mi>m</mi>\u0000 </mrow>\u0000 <annotation> $65,{upmu }mathrm{m}$</annotation>\u0000 </semantics></math> spherical grains, was initially 1.4 cm thick, allowing ripple and scour hole formation. The formation of wave-orbital ripples was dependent on meadow density and current magnitude. Over bare beds and sparse meadows, ripples were present and not impacted by the addition of current, such that the wave velocity resuspension threshold with current was the same as that in pure wave conditions. In medium-density meadows, the addition of current reduced ripple height due to plant-generated turbulence. As current increased, ripple size and ripple-generated turbulence decreased, requiring a higher wave velocity to resuspend sediment. That is, for medium density meadows, the critical wave velocity increased as the current velocity increased. Finally, in dense meadows, no ripples formed and resuspension was driven by a critical value of plant-induced turbulence, which was proportional to the total velocity (current plus wave velocity), such that as the current velocity increased, the critical wave velocity decreased. A model predicting the critical wave velocity for the dense meadow was derived based on the assumption that resuspension was driven by a critical level of stem-generated turbulence.</p>","PeriodicalId":15887,"journal":{"name":"Journal of Geophysical Research: Earth Surface","volume":"130 6","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-06-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JF008050","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144244167","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Outwash Events Inhibit Vegetation Recovery and Prolong Coastal Vulnerability 冲刷事件抑制植被恢复并延长海岸脆弱性
IF 3.5 2区 地球科学
Journal of Geophysical Research: Earth Surface Pub Date : 2025-06-07 DOI: 10.1029/2024JF008162
Jin-Si R. Over, Christopher R. Sherwood
{"title":"Outwash Events Inhibit Vegetation Recovery and Prolong Coastal Vulnerability","authors":"Jin-Si R. Over,&nbsp;Christopher R. Sherwood","doi":"10.1029/2024JF008162","DOIUrl":"https://doi.org/10.1029/2024JF008162","url":null,"abstract":"<p>Overwash, when high ocean water levels and waves flood a coastline, is a common phenomenon that can lead to washover deposits and barrier rollover. Outwash, by contrast, involves seaward flow, often driven by high back-barrier water levels, and can produce washout channels and nearshore deposition. Our observations show that washout channels were quickly (days to weeks) filled and reshaped into beaches, berms, and washover deposits and ponds often formed at the landward ends. However, there was a significant delay in revegetation of former washout areas compared with washover areas. North Core Banks, North Carolina, was affected by repeat hurricanes in different ways: Hurricane Florence (2018) deposited large washover fans 0.5–1 m thick, and Hurricane Dorian (2019) removed 1–4 m of sediment from washout channels. Aerial surveys captured vegetation recolonization on the Florence washover fans within a year but, after Dorian, surveys showed that although the washout channels and ponds quickly filled with marine sand, the channel throats and new washover platforms remained mostly unvegetated for five years. New vegetation growth was associated with the washout ponds and was characteristic of low-elevation hydrophilic environments. We observed comparable outcomes at washout and washover locations on the coasts of Texas and New York and suggest that outwash interrupts the normal cycle of vegetation and dune growth that is key to rebuilding barrier islands after storms. The lack of vegetation in the former washout channels prolongs vulnerability to overwash, further delaying recovery. Our findings have implications for best-management practices and modeling of coastal geomorphic evolution.</p>","PeriodicalId":15887,"journal":{"name":"Journal of Geophysical Research: Earth Surface","volume":"130 6","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JF008162","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144232304","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Rainfall Thresholds for Postfire Debris-Flow Initiation Vary With Short-Duration Rainfall Climatology 火灾后泥石流起始的降雨阈值随短时降水气候而变化
IF 3.5 2区 地球科学
Journal of Geophysical Research: Earth Surface Pub Date : 2025-06-07 DOI: 10.1029/2024JF007781
David B. Cavagnaro, Scott W. McCoy, Donald N. Lindsay, Luke A. McGuire, Jason W. Kean, Daniel T. Trugman
{"title":"Rainfall Thresholds for Postfire Debris-Flow Initiation Vary With Short-Duration Rainfall Climatology","authors":"David B. Cavagnaro,&nbsp;Scott W. McCoy,&nbsp;Donald N. Lindsay,&nbsp;Luke A. McGuire,&nbsp;Jason W. Kean,&nbsp;Daniel T. Trugman","doi":"10.1029/2024JF007781","DOIUrl":"https://doi.org/10.1029/2024JF007781","url":null,"abstract":"<p>The size, frequency, and geographic scope of severe wildfires are expanding across the globe, including in the Western United States. Recently burned steeplands have an increased likelihood of debris flows, which pose hazards to downstream communities. The conditions for postfire debris-flow initiation are commonly expressed as rainfall intensity-duration thresholds, which can be estimated given sufficient observational history. However, the spread of wildfire across diverse climates poses a challenge for accurate threshold prediction in areas with limited observations. Studies of mass-movement processes in unburned areas indicate that thresholds vary with local climate, such that higher rainfall rates are required for initiation in climates characterized by frequent intense rainfall. Here, we use three independent methods to test whether initiation of postfire runoff-generated debris flows across the Western United States varies similarly with climate. Through the compilation of observed thresholds at various fires, analysis of the spatial density of observed debris flows, and quantification of feature importance at different spatial scales, we show that postfire debris-flow initiation thresholds vary systematically with short-duration rainfall-intensity climatology. The predictive power of climatological data sets that are readily available before a fire occurs offers a much-needed tool for hazard management in regions that are facing increased wildfire activity, have sparse observational history, and/or have limited resources for field-based hazard assessment. Furthermore, if the observed variation in thresholds reflects long-term adjustment of the landscape to local climate, rapid shifts in rainfall intensity related to climate change will likely induce spatially variable shifts in postfire debris-flow likelihood.</p>","PeriodicalId":15887,"journal":{"name":"Journal of Geophysical Research: Earth Surface","volume":"130 6","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JF007781","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144232303","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Surging Processes and Mechanisms at Small Glaciers in the Qilian Mountains, Northwestern China, Revealed by Long-Term, Temporally Dense Remote Sensing Observations 祁连山小冰川涌动过程与机制:长期、时间密集遥感观测
IF 3.5 2区 地球科学
Journal of Geophysical Research: Earth Surface Pub Date : 2025-06-06 DOI: 10.1029/2024JF008157
Lei Guo, Jia Li, Laurane Charrier, Amaury Dehecq, Luc Beraud, Zhiwei Li, Xin Li, Jianjun Zhu, Long Li, Yingzheng Wang
{"title":"Surging Processes and Mechanisms at Small Glaciers in the Qilian Mountains, Northwestern China, Revealed by Long-Term, Temporally Dense Remote Sensing Observations","authors":"Lei Guo,&nbsp;Jia Li,&nbsp;Laurane Charrier,&nbsp;Amaury Dehecq,&nbsp;Luc Beraud,&nbsp;Zhiwei Li,&nbsp;Xin Li,&nbsp;Jianjun Zhu,&nbsp;Long Li,&nbsp;Yingzheng Wang","doi":"10.1029/2024JF008157","DOIUrl":"https://doi.org/10.1029/2024JF008157","url":null,"abstract":"<p>A glacier surge, an exceptional phenomenon of mass redistribution, is one of the least understood dynamic processes in cryospheric science. Long-term detailed changes in glacier elevation and flow velocity are crucial for assessing surge dynamics. However, capturing complex changes during surges through traditional methods, especially on small and narrow valley glaciers, is often hampered by the limitations in spatiotemporal resolution of available satellite records. In this study, we investigated the long-term changes of small surging glaciers in the Qilian mountains whose dynamics remain poorly understood. Using ASTER and Landsat imagery, we employed the two newly developed methods specifically designed for surging glaciers to derive long-term monthly flow velocity and elevation time series. Combing with historical morphological analysis, our results successfully captured the detailed surging process of five glaciers. One glacier (GLIMS ID: G097781E38470N) experienced a major surge during 2002–2008, characterized by abrupt acceleration and mass transfer during 2002–2005. One glacier (G097762E38509N) underwent a surge with terminus advance prior to 2000. Two glaciers (G097722E38519N and G097681E38536N) experienced gradual surges that lasted over 10 years. The fifth glacier (G097731E38477N) shows early surge initiation, characterized by recent acceleration and thickening in its middle trunk. Considering the long duration, glacier surges in this region appear primarily thermal-controlled. However, the pre-surge stage and sudden mass release suggest a possible impact from saturated soft sediment failure. This research demonstrates the potential of advanced time-series methods for revealing diverse surge patterns and surge evolution of small glaciers, and provides new insights into the surge dynamics in this region.</p>","PeriodicalId":15887,"journal":{"name":"Journal of Geophysical Research: Earth Surface","volume":"130 6","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144220344","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Quantification of Particle Velocities and Energy Regime in an Aeolian Abrasion Chamber 风成磨蚀室中粒子速度和能量状态的量化
IF 3.5 2区 地球科学
Journal of Geophysical Research: Earth Surface Pub Date : 2025-06-03 DOI: 10.1029/2024JF008218
Joanna E. Bullard, Lucrecia Alvarez-Barrantes, Cheryl McKenna Neuman, Patrick O’Brien
{"title":"Quantification of Particle Velocities and Energy Regime in an Aeolian Abrasion Chamber","authors":"Joanna E. Bullard,&nbsp;Lucrecia Alvarez-Barrantes,&nbsp;Cheryl McKenna Neuman,&nbsp;Patrick O’Brien","doi":"10.1029/2024JF008218","DOIUrl":"https://doi.org/10.1029/2024JF008218","url":null,"abstract":"<p>Particle breakdown and fine sediment production by wind abrasion is of long-standing interest in aeolian science as it contributes to erosion and dust production on Earth and other planetary bodies. The process of aeolian abrasion is largely measured in laboratories to enable standardization of parameters and allow simulation of saltation over long time periods. To be effective, abrasion simulators must reproduce particle interactions similar to those observed in the natural environment. This paper quantifies the particle velocities, pathways and energy regime within a widely used “test-tube” abrasion chamber. For 17 different sand samples, the instantaneous two-dimensional vertical and horizontal velocity components of particles moving within the chamber were sampled using a laser Doppler anemometer. Similar to a natural saltation cloud, the movement of particles in the chamber is stochastic and there is a positive relationship between the air inflow rate and the depth of the saltation layer. For air inflow of 14.9 m s<sup>−1</sup>, particle velocities range from 0.01 to 3.2 m s<sup>−1</sup> with median velocity for all particles in the chamber varying from 0.29 to 0.56 m s<sup>−1</sup>, and total energy ranging from 0.54 to 1.38 J kg<sup>−1</sup>. These values are similar to those determined for natural saltation clouds. For a constant air inflow rate, the mean total particle velocity increases with particle size. Air inflow rate has a significant effect on mean total particle velocity but between 10 and 100 g the quantity of sample tested is not important. The contribution of this type of experiment to understanding aeolian abrasion processes is evaluated.</p>","PeriodicalId":15887,"journal":{"name":"Journal of Geophysical Research: Earth Surface","volume":"130 6","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JF008218","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144197474","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Increased Hydraulic Roughness in Alluvial Rivers Created by Sand-Mining Sculpted Bed Features 采砂雕刻河床特征增加了冲积河流的水力粗糙度
IF 3.5 2区 地球科学
Journal of Geophysical Research: Earth Surface Pub Date : 2025-06-03 DOI: 10.1029/2024JF008189
C. R. Hackney, J. Cisneros, S. Heng, S. E. Darby, J. Leyland, K. Konsoer, D. R. Parsons
{"title":"Increased Hydraulic Roughness in Alluvial Rivers Created by Sand-Mining Sculpted Bed Features","authors":"C. R. Hackney,&nbsp;J. Cisneros,&nbsp;S. Heng,&nbsp;S. E. Darby,&nbsp;J. Leyland,&nbsp;K. Konsoer,&nbsp;D. R. Parsons","doi":"10.1029/2024JF008189","DOIUrl":"https://doi.org/10.1029/2024JF008189","url":null,"abstract":"<p>Alluvial bedforms are a first order control on flow resistance, water levels and rate of sediment transport. Their morphologies are a direct reflection of the hydraulic and sedimentological conditions under which they are formed. Studies of natural dunes in large river systems have shown that low angled dunes are dominant, characterized by reduced flow resistance and limited recirculation of flow in their lee-slopes. However, increasingly, alluvial rivers are influenced by human activities, such as sand extraction, that directly impact the morphologies of river beds and bedforms. Here, we present a comparison of the morphologies of natural and anthropogenically influenced bedforms observed through multibeam echo sounder surveys on the Mekong River in Cambodia. We show that anthropogenic bedforms have higher amplitudes (<i>μ</i> = 2.8 m, <i>σ</i> = 1.0 m), steeper leeside angles (<i>μ</i> = 20.6°, <i>σ</i> = 5.8°) and shorter wavelengths (<i>μ</i> = 100.1 m, <i>σ</i> = 87.9 m) compared to natural dunes (amplitude: <i>μ</i> = 1.79 m <i>σ</i> = 0.86 m, leeside angle: <i>μ</i> = 11.8° <i>σ</i> = 5.7°, wavelength: <i>μ</i> = 117.0 m, <i>σ</i> = 89.1 m). Our data suggests that the form roughness of anthropogenic bedforms is higher (median <i>k</i><sub><i>sf</i></sub> = 1.23) than natural bedforms found in sections of the Mekong unaffected by mining (median <i>k</i><sub><i>sf</i></sub> = 0.49). As a result, flow patterns subsequently force suspended load over bedforms, meaning sediment is unable to infill mining pits. Anthropogenic bedforms may represent a significant and previously under-represented control of flow and sediment transport in alluvial river systems.</p>","PeriodicalId":15887,"journal":{"name":"Journal of Geophysical Research: Earth Surface","volume":"130 6","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JF008189","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144197473","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Airborne and Spaceborne Mapping and Analysis of the Subglacial Lake D2 in David Glacier, Terra Nova Bay, Antarctica 南极洲特拉诺瓦湾大卫冰川D2冰下湖的机载和星载制图与分析
IF 3.5 2区 地球科学
Journal of Geophysical Research: Earth Surface Pub Date : 2025-06-02 DOI: 10.1029/2024JF008142
Hyeontae Ju, Seung-Goo Kang, Hyangsun Han, Lucas H. Beem, Gregory Ng, Kristian Chan, Taewook Kim, Joohan Lee, Jongik Lee, Yeadong Kim, Sukjoon Pyun
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