Article
Geography, Physical
David Luzi, Marwan A. Hassan, Elli Papangelakis, Brett Eaton
Summary: The research findings suggest that there is a counter-clockwise hysteresis relation between sediment storage and sediment transport rate in gravel-bed rivers, indicating aggradation-degradation cycles. Even under steady sediment supply conditions, aggradation-degradation cycles can occur when the sediment transport rate temporarily approaches the sediment supply rate. The transport rate of the channel is influenced by the channel morphology, and hysteresis in the transport-storage relation is more likely to occur when the channel is near a transport equilibrium.
Article
Water Resources
Jose A. Bonilla-Porras, Aronne Armanini, Alessandra Crosato
Summary: This study explores the impact of instream vegetation on bedload transport and proposes a new model that extends Einstein's parameters to incorporate vegetation effects, resulting in improved predictions compared to existing methods. Through calibration based on laboratory data and validation against published measurements, the new formulations show better agreement with observed bedload rates and significant improvements over previous methods like Baptist's (2005) approach.
ADVANCES IN WATER RESOURCES
(2021)
Article
Geosciences, Multidisciplinary
Santiago J. Benavides, Eric Deal, Matthew Rushlow, Jeremy G. Venditti, Qiong Zhang, Ken Kamrin, J. Taylor Perron
Summary: The study discusses how sediment transport near the threshold of grain motion is influenced by rare transport events, making it difficult to calibrate sediment transport laws and define a clear threshold for grain entrainment. The research presents a model to capture this intermittency and utilize noisy statistics of sediment transport to predict the sediment entrainment threshold and fluid stress variations. The findings suggest strategies for improving measurements and predictions of sediment flux and hint at potential changes in the sediment transport law near the threshold of motion.
GEOPHYSICAL RESEARCH LETTERS
(2022)
Article
Engineering, Civil
Brenden Riddle, Jimmy Fox, Yi-Tin Wang, Bill Ford, Tyler Mahoney, Erik Pollock, Jason Backus, Nabil Al Aamery
Summary: Despite their importance for freshwater biogeochemical cycles and ecological restoration, there is a lack of knowledge about sediment organic matter degradation and its influence on water quality for low gradient agriculturally impacted streams. We conducted aerobic incubation experiments and found that degradation rates vary across sediment type and are influenced by the connectivity regimes of low gradient systems. The results support our hypothesis and suggest that sediment connectivity regime controls the biogeochemical cycling of the stream network.
JOURNAL OF HYDROLOGY
(2023)
Article
Engineering, Environmental
Xiaocui Li, Lei Huang, Danny Reible, Xiong Zeng, Siwen Liu, Jiahao Fu, Kai Wang, Hongwei Fang
Summary: The relationship between sediment erosion and phosphorus release under the remediation strategy of contaminated sediment backfilling (CSBT) was investigated. The results showed that improving bed stability through CSBT significantly enhanced the robustness of the sediment-water interface and reduced sediment erosion and phosphorus release. This study provides a theoretical reference for controlling sediment pollution and supports river and lake ecological management and environmental restoration.
Article
Geosciences, Multidisciplinary
Santiago J. Benavides, Eric Deal, Jeremy G. Venditti, Ryan Bradley, Qiong Zhang, Ken Kamrin, J. Taylor Perron
Summary: Near the threshold of grain motion, sediment transport is intermittent, with rare bursts and long periods of low transport. The origin of intermittency is found in the velocity distributions of rolling grains, rather than the activity of grains. Incorporating this type of intermittency into sediment transport models can lead to improved predictions of sediment flux.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Environmental Sciences
Veronica Carrillo, John Petrie, Luis Timbe, Esteban Pacheco, Washington Astudillo, Carlos Padilla, Felipe Cisneros
Summary: The study introduced an experimental procedure to determine bedload sediment transport rates in channels with high gradients and coarse sediment. Through laboratory experiments, a mathematical bedload transport model was established, showing agreement with some models in existing literature. The closest match was found with models developed for steep slopes considered in the study.
Article
Astronomy & Astrophysics
Tobias Nicollier, Gilles Antoniazza, Dieter Rickenmann, Arnd Hartlieb, James W. Kirchner
Summary: The spatio-temporal variability of bedload transport processes poses challenges for the Swiss plate geophone (SPG) bedload monitoring system. In this study, controlled flume experiments and impact tests were conducted to investigate the factors influencing the signal response of the SPG system and the potential bias caused by seismic waves generated by impacting particles. Based on the findings, a filter method was developed to eliminate the apparent impacts and improve the accuracy of bedload estimates. The filter was applied to four field calibration datasets, effectively reducing site-to-site differences.
EARTH AND SPACE SCIENCE
(2022)
Article
Environmental Sciences
Vaclav Matousek
Summary: In this study, granular flow is modeled using principles of kinetic theory of granular flow and mixing-length theory of flow turbulence. The model is tested and calibrated with experimental results.
Article
Cell Biology
Albert Lu, Frank Hsieh, Bikal R. Sharma, Sydney R. Vaughn, Carlos Enrich, Suzanne R. Pfeffer
Summary: This study conducted two genome-wide CRISPR screens to explore genes related to lysosomal cholesterol and bis(monoacylglycero)phosphate levels, as well as modifiers of NPC1 function in lysosomal cholesterol export. The findings confirm the tight coregulation of cholesterol and bis(monoacylglycero)phosphate in cells and unexpectedly reveal a negative regulatory role of the ER-localized SNX13 protein in lysosomal cholesterol export. The experiments provide novel insights into the regulation of lysosomal lipids and modification of these processes by new gene products.
JOURNAL OF CELL BIOLOGY
(2021)
Article
Environmental Sciences
C. A. Chooplou, M. Vaghefi, M. Akbari
Summary: This study mainly focused on the role of submerged parallel vanes' positioning across the channel width in decreasing the depth of scouring around the bridge pier. The results showed that placing the submerged vanes at the channel's central axis caused the greatest reduction in scouring depth, with a reduction of 51% compared to the tests without vanes. Additionally, placing the submerged vanes at specific distances from the pier's centerline resulted in local scour reductions of 30% and 25%.
INTERNATIONAL JOURNAL OF ENVIRONMENTAL SCIENCE AND TECHNOLOGY
(2023)
Article
Geography, Physical
Melanie Vah, Alaa Khoury, Armelle Jarno, Francois Marin
Summary: An experimental investigation of the entrainment threshold of sediment grains was conducted, and a processing method based on image correlation was presented. The method was not affected by individual judgement, and it exhibited three thresholds related to surface mobility of the sediment bed. The method was sensitive to different parameters, and the minimum size for reliable estimations was found. Tests with homogeneous sands showed similar results to reference-based methods. The method could be an alternative with its simplicity, precision, and direct correlation between threshold velocity and bed mobility.
EARTH SURFACE PROCESSES AND LANDFORMS
(2022)
Article
Engineering, Civil
Barbara Zanchi, Alessio Radice
Summary: The laboratory experiments were designed to quantify the height and migration rate of an aggrading gravel front with a focus on the Froude number and load ratio as control parameters. The results showed that the dimensionless height and celerity of the aggradation front were determined by the load ratio and Froude number.
JOURNAL OF HYDRAULIC ENGINEERING
(2021)
Article
Chemistry, Multidisciplinary
Woochul Kang, Kyungsu Lee, Eun-kyung Jang
Summary: This study assessed the applicability of sediment yield and transport estimation models developed using data mining techniques and validated them through field surveys. Models based on hydraulic explanatory variables showed excellent predictability due to the large amount of calibration data used. Sufficient reliable data is necessary in developing sediment yield estimation models using data mining. Practical applications of data mining in existing models require comprehensive considerations of the purpose, background, and data range, as well as periodic updates to address temporal and spatial lumping issues.
APPLIED SCIENCES-BASEL
(2022)
Article
Geology
Anat Ash-Mor, Ahuva Almogi-Labin, Vincent M. P. Bouchet, Laurent Seuront, Tamar Guy-Haim, Zvi Ben-Avraham, Revital Bookman
Summary: This study investigates the transport of continental shelf sediments to the deep ocean in simulated high flow conditions. Results show that at a velocity of 80 cm/s, different shapes of larger benthic foraminifera shells efficiently suspend and transport in large quantities throughout the water column, and 80 cm/s is also the threshold for the formation of thick coarse deposits in the slope sedimentary record.
Article
Geography, Physical
A. Securo, C. Del Gobbo, L. Rettig, S. Pillon, A. De Luca, D. Fontana, E. Benedetti Fasil, R. R. Colucci
Summary: Small glaciers in temperate mountain regions have experienced significant reduction and unprecedented melt rates in recent years. Some glaciers have transitioned from clean ice to debris-covered or even rock glaciers. This study examines the surface elevation change of the Popera Alto glacier in the Sesto Dolomites using LiDAR and Structure from Motion surveys, and analyzes its evolution in terms of surface cover and geomorphic processes. The glacier has lost an average of 0.35 m water equivalent per year over the past 16 years, with active modification of its surface cover by geomorphic processes. The role of debris and local topography feedback has allowed the resilience of the glacier, leading to a marked difference between the current environmental equilibrium line altitude (envELA) and the effective ELA (effELA) of the glacier.
Article
Geography, Physical
Zhenzhen Yan, Yaolin Shi, Lili Kang, Xiangtao Fan
Summary: This study proposes a quantitative regional deformation model based on global positioning system (GPS) data to quantitatively analyze the morphological evolution of rivers in the Three Rivers Region. It finds that tectonic deformation phases significantly control regional landscape development and drainage features.
Article
Geography, Physical
Said Mukhtar Ahmad, Nitheshnirmal Sadhasivam, Mona Lisa, Luigi Lombardo, Mustafa Kemal Emil, Amira Zaki, Cees J. Van Westen, Islam Fadel, Hakan Tanyas
Summary: In this study, we investigated a large slow-moving landslide in Northern Pakistan, using Interferometric Synthetic Aperture Radar (InSAR) analysis. Our results showed that the crown of the landslide is moving faster than the surrounding regions, while the footslope experienced high deformations. We discussed the possible roles of meteorologic and anthropogenic factors in causing these deformations.
Article
Geography, Physical
Shuang Bian, Xibin Tan, Yiduo Liu, Suoya Fan, Junfeng Gong, Chao Zhou, Feng Shi, Michael A. Murphy
Summary: The Yarlung River's drainage divide is primarily moving north due to variations in precipitation across the Himalayas. The Gangdese drainage divide shows predominantly northward and southward migration, controlled by base-level rise and downstream influences. The presence of north-trending rifts separates the drainage divides into five zones, each with a distinct migration pattern.
Article
Geography, Physical
Joon-Young Park, Seok Yoon, Deuk-Hwan Lee, Seung-Rae Lee, Hwan-Hui Lim
Summary: This study developed a multiple-regression model to estimate site-specific average growth rates of debris flow events. The proposed model was validated through a case study and showed reasonable predictions of debris flow velocities and heights.
Article
Geography, Physical
Nicholas Reilly Mccarroll, Arnaud Temme
Summary: New geochronological data from hillslope boulder armor in the Flint Hills reveal the rates and timing of lateral retreat in the landscape. Surfaces of limestone boulders dating back to the Pleistocene era were found, and the ages of the hillslope armor increased with distance from the limestone bench. The estimated rate of lateral retreat in this landscape is 0.02 mm/yr.
Article
Geography, Physical
Xinbo Yao, Yuntao Tian
Summary: By studying the Longmenshan-Minshan drainage divide, we found that it has reached a dynamic steady state, indicating a balance between erosion and rock uplift. This study also reveals the process of formation and evolution of the divide and raises questions about the effectiveness of divide migration metrics.
Article
Geography, Physical
Junhui Yu, Pin Yan, Yanlin Wang, Guangjian Zhong, Changliang Chen
Summary: The seafloor mounds in the Chaoshan Depression of the South China Sea are identified as mud volcanoes, with fluids coming from underlying mud-fluid diapirs. The hydrocarbon gases feeding the mud volcanoes and diapirs are reasoned to originate from deep Mesozoic source rocks, indicating significant Mesozoic hydrocarbon potential in the Chaoshan Depression.
Article
Geography, Physical
Marius Huber, Luc Scholtes, Jerome Lave
Summary: This paper investigates the relationships between hillslope stability and fabric anisotropy of brittle rock materials and the implications for landscape shaping. It explores the different stability modes and movement characteristics of anisotropic materials, and demonstrates the significant control of material anisotropy on landscape shaping.
Article
Geography, Physical
Shubhra Sharma, Anil D. Shukla
Summary: The study investigates the relationship between glacial dynamics and lake sedimentation during the mid-Holocene climate variability in the Southern Zanskar ranges. It utilizes geomorphological disposition, elemental geochemistry, and optical chronology of relict lake sediment to reconstruct the pattern of minor glacier responses to climate variability. The results indicate six centennial to millennial-scale climatic phases, with warmer phases represented by decreased mineralogical fine grain flux and increased coarse grain flux. The study highlights the potential of relict lake sediment and para/peri-glacial landforms in understanding glacial dynamics and climate change during the Holocene.
Article
Geography, Physical
Jean-Francois Bernier, Sydney W. Meury, Patrick Lajeunesse
Summary: In this study, an approach combining various data and observation methods was proposed to improve the monitoring of landfast ice dynamics and its geomorphic impact on sedimentary systems. The results demonstrate the ability of the approach to accurately measure interannual variations in landfast ice and constrain geomorphic changes. Additionally, the study found a strong relationship between the severity of freezing seasons and the response of landfast ice to hydrometeorological events, with different geomorphic responses observed under different winter conditions.
Article
Geography, Physical
Heping Shu, Fanyu Zhang
Summary: This study investigates the relationship between susceptibility of soil-water hazards and human activities, geoheritage sites in the Loess Plateau, China. Landslide and gully erosion susceptibility were obtained using gradient boosting and support vector machines, and a hazard matrix was formed to couple landslide and gully erosion susceptibility. The study found different trends in the magnification times of soil-water hazards chain under different scenarios.
Article
Geography, Physical
Guangqiang Qian, Zhuanling Yang, Xuegang Xing, Zhibao Dong, Youyuan Guo
Summary: Granule ripples are aeolian landforms armored against erosion by coarse grains. This study investigates their seasonal morphological evolution and migration in the Sanlongsha Dune Field. The findings show that wind events, especially those exceeding the threshold velocities of coarse grains, significantly influence the morphodynamics of granule ripples. The study highlights the importance of considering the reptation and saltation of coarse grains in future research on granule ripples.