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Hydrological models are vital for water management to determine in-stream flow, irrigational water, domestic water supply, and biodiversity conservation. This study formulates a hydrological model with a novel approach for streamflow and sediment load in the QGIS-supported Soil and Water Assessment Tool for the Halda River catchment, a unique ecological habitat for natural carp spawning and freshwater sources. The daily simulation uses an innovative stage-discharge relationship technique from available 15-day interval flow data. The model evaluation parameters R2 values 0.80 and 0.62, and NS values 0.81 and 0.61 for calibration and validation of streamflow suggested excellent agreement in the seasonal cycle and most of the monsoon peak flow. The streamflow/precipitation ratio indicates a significant influence of groundwater through infiltration. The baseflow shows a decreasing trend. The sediment load based on suspended sediment concentration at a downstream location is 1,625 tons/day. On the contrary, the model prediction is 30 times lower. The scattered sediment load data support the model estimate by considering relatively lower intervention or land use change in its upstream. This model provides a baseline for daily flow and sediment load for scenario modeling (e.g., climate change, land use change) for environmental flow estimation of the fish habitat, freshwater supply, irrigation, and salinity intrusion. [ABSTRACT FROM AUTHOR]

Tidal flats, crucial for biodiversity and ecosystem services, are facing significant alterations due to human activities such as reclamation. In South Korea, over 65% of tidal flats have been reclaimed since the 1970s, resulting in morphological changes and altered sediment transport dynamics. This study investigates sediment transport processes in the artificial Aam tidal channel, created as part of the megacity development project in Incheon, Korea. Using data from Acoustic Doppler Current Profiler and Vector instruments deployed in 2019 and 2021, we analyzed tidal asymmetry, current velocities, shear stress, and suspended sediment concentration. Our results reveal a pronounced tidal asymmetry influencing sediment transport, with ebb-dominant currents near the channel entrance and flood-dominant currents in the interior. We observed significant sediment deposition in the landward section of the channel, driven by tidal mixing asymmetry and rainfall events. These findings highlight the complex interactions between artificial structures and natural sediment dynamics, informing future coastal development and management strategies. [ABSTRACT FROM AUTHOR]

Sediment fingerprinting technology is widely used to differentiate sediment sources. However, despite its long-recognized benefits, there it has been seldom applied to assess the variability of sediment sources during storm events. In this study, sediment fingerprinting is used for four storm events to determine the dynamic changes in sediment sources throughout them in the black soil region in Northeast China. Three potential sediment sources—cultivated land, unpaved roads, and gullies—were effectively differentiated using four geochemical tracers (As, Be, Cs, and Cu), with an accuracy of 100%. The relative sediment contribution from each source was determined using linear and Bayesian mixing models. The mean absolute fit (MAF) values of the linear mixing model (MAFmean = 0.976–0.949) were higher than those of the Bayesian mixing model (MAFmean = 0.921–0.992), indicating that the first performed better. Cultivated land was the primary source of the sediment load, accounting for 59.03% of it (load-weighted mean = 68.29%), followed by the gullies (37.15%, load-weighted mean = 28.09%), and unpaved roads (3.90%, load-weighted mean = 3.69%) for the four storm events. In addition, a high variability in sediment source contribution was observed during the storm events. Cultivated land was the dominant sediment source during storm events with higher sediment concentrations (logarithmic function, r2 = 0.878, p

In-situ mooring systems with acoustic Doppler current profilers were installed in the western (TM01) and eastern (TM02) parts of Yeosu Bay from September 3 to October 2, 2021, to understand the controlling mechanisms of suspended sediment transport. In the bay, freshwater from the Seomjin River freely exchanges with seawater from the open sea. Over the mooring period, current flows were mainly dominated by ebb tides. Power spectral density analysis of the suspended sediment concentration (SSC) exhibited a quarter-diurnal (6.21 h) frequency at TM01 and a semi-diurnal (12.42 h) frequency at TM02. The results suggested that SSC variations in the western part were driven primarily by local sediment resuspension, while they were influenced predominantly by horizontal advection in the eastern part. Differences in SSC variation at the two stations could be due to the physical properties of the bed sediments (TM01: sandy mud containing shell fragments, TM02: mud). Such current flows and SSC variations over the tidal cycles caused an imbalance of sediment transport. At TM01, the sediment fluxes were dominantly seaward due to tidal pumping (88% of the total) and the discharge of suspended sediments in the surface layer by residual circulation. At TM02, landward sediment fluxes were driven primarily by the residual current (73% of the total). Although the suspended sediment fluxes tended to be compensated and balanced mutually by circulation over the entire period, the suspended sediment fluxes at TM02 were approximately twice higher than those at TM01. This was caused by the difference in SSC asymmetry between flood and ebb at the two stations. The mechanisms controlling the transport of suspended sediment could vary spatially, and the relative contribution of tidal pumping and residual circulation could result in an imbalance of sediment transport. [ABSTRACT FROM AUTHOR]

Significane The analysis of source-to-sink system is a comprehensive study of tectonic geology, sedimentology, and sequence stratigraphy. Because of its integral, dynamic, and semiquantitative-quantitative characteristics, it has attracted widespread attention. Progress This review first introduces the key issues of the deep-time source-to-sink systems (pre-Quaternary systems), which include the quantitative characterization of sediment mass balance and the control of the transport process on the sediment. Due to the lack of stratigraphic records and the difficulty in obtaining parameters, the research is still challenging.Second, it reviews the quantitation methods of deep-time source-to-sink systems that can be classified into three categories, namely, geochronology, uniformitarianism, and sedimentology. By obtaining information such as geomorphological parameters, hydraulic parameters, erosion rates, and sediment flux, various methods establish the quantitative relationships between "sources" and "sinks" and then rebuild the sedimentary basin infilling history. This article introduces the principles and related parameters of different methods and then compares the advantages and limitations to provide a reference for future research. It is believed that geochronology is widely used, and the core lies in provenance analysis. The key to uniformitarianism is the analogy of geological background and the selection of geological parameters. The sedimentology is controlled by multiple variables, and the tectonic-climate background and research scale need to be considered comprehensively. Conclusions and Prospects Finally, this review states the development of quantitative analysis of deep-time source-to-sink systems. Under the guidance of the important idea of "the present is the key to the past", the research needs to focus on the provenance systems, sediment routing systems, sediment dispersal, and redistributive process, and coupling relationship between various parameters. Research also needs to pay attention to quantitative analysis at multiple timescales and multidisciplinary dynamic analysis. Compared with continental margin source-to-sink systems, continental lacustrine source-to-sink system patterns and prediction models need to be further improved.

The nature and amount of sediment transferred from one plate to the other near the subduction interface partly determines the tectonic and seismogenic regimeof a margin. Examination of over 500 multichannel seismic lines has enabled us to build up a global database of subduction zone front characteristics at unprecedented spatial resolution. The total thickness of sediment in the trench below the deformation front, as well as that of the subduction channel at a distance from the trench, combined with other indices such as the tectonic regime of the forearc or the migration of the volcanic front, have enabled us to revisit the accretionary or erosional character of active margins. Preliminary conclusions, based on ~3/4 of sufficiently documented subduction zones, show a predominance of the erosive character of subduction over the last million years. The flux of solid matter through the shallow part of the subduction channel is of the order of 1.5 km³/yr, and that of pore fluids 0.4 km³/yr. Some subduction zones, such as theMediterranean, are characterized by exceptional solid flux in the channel, while fluid flux is comparatively moderate. This is due to the fact that channel sediments are compacted even before subduction. Overall, fluid flux in the channel is greater under erosivemargins, due to the higher rate of subduction and often higher porosity. Maximum porosity in the channel is reached when there is neither accretion nor tectonic erosion. [ABSTRACT FROM AUTHOR]

A seasonal variability in flow and sediment flux at the Socheongcho Ocean Research Station (SORS) on the west coast of Korea in 2018 was investigated to elucidate the formation of a two-layered flow structure and changes in sediment transport during stratification. An analysis of SORS data revealed stable temperatures (5–10 °C) in deeper waters, while surface temperatures rose from 6 °C in April to a peak of 30 °C in late August, gradually declining and leading to full water column mixing by late November. This temperature variation induced stratification, influencing the development of a two-layered flow structure. In winter, a singular flow structure was observed, contrasting with the emergence of a two-layered structure as stratification progressed. In the surface layer, residual currents flowed northward in summer and southward in winter, consistent with previous studies. In deeper layers, a southward residual current persisted, irrespective of the season. Sediment flux consistently moved southward, regardless of the season or water depth, with notably higher cumulative sediment flux in the deeper layer (1300 kg·m−2s−1) compared to the surface layer (300 kg·m−2s−1). These findings diverge notably from previous studies, providing new insights into ocean currents and material transport in the Yellow Sea. [ABSTRACT FROM AUTHOR]

Discrepancies between estimated sediment and actual yields are large. The sedimentation often causes severe damage due to a lack of on-site measurement data in the current disaster prevention system. This paper presents a robust early-warning system in which the statistical analysis used to predict sedimentation is conducted within the context of the underlying physical mechanisms. This three-phase early-warning system employs data collection, data generation, and AI (Artificial Intelligence) prediction. Data collection involves the use of HEC-HMS (Hydrologic Engineering Center – Hydrologic Modeling System) to transform measured precipitation data into flow discharge from various sub-catchments. Empirical formulas related to landslide volume and soil erosion are then used to establish suitable boundary conditions for data generation. Finally, a 2D model, SRH-2D (Sediment and River Hydraulic-Two Dimension model), is used to simulate data pertaining to temporal variations in sediment flux under various storm event scenarios. The simulated data are then used as input for the training and testing three artificial neural networks. The primary strength of this study is to improve the prediction ability in large-scale sedimentation issues in mountain rivers. These models returned good prediction results with 1–6 h lead times by interdisciplinary integration with the hydraulic and statistical fields. HIGHLIGHTS The sediment flux in the mountain basin was successfully predicted with field data and data generated by numerical modeling.; The accuracy of sediment flux predictions could be improved by adopting various data sources and greatly improves the results of conventional that rely on a single variable.; The sediment flux prediction obtained a reasonable result, and there were no difficulties in predicting underlying trends.;

[Objective] The characteristics of sand and dust transport amount and particle size on the windward and leeward sides of a natural Populus euphratica riparian forest at the Arghan section of the lower reaches of the Tarim River under the prevailing wind direction were studied in order to provide a theoretical basis for its windbreak and sand fixation capacity. [Methods] Sediments were collected from two windward sites (Y1 and Y2) and two leeward sites (B1 and B2) of the forest at five heights of 10, 30, 50, 100, and 150 cm near the surface using a BSNE sand collector. The particle size characteristics of the sand samples were then measured using a Microtrac S3500 laser diffraction particle size analyzer. [Results] ① The horizontal flux of sand and dust in the four sample plots followed either a power function or exponential function distribution, and total sediment transport followed the order of Y1 > Y2 > B1 > B2. The sediment transport for each sample plot decreased with increasing height from the soil surface. ② The reduction of sediment on the leeward side compared with the windward side ranged from 35% to 80% less than on the windward side, indicating that the natural P. euphratica riparian forest in the lower reaches of the Tarim River has obvious windbreak and sand fixation benefits. ③ The average particle size of sand grains at all heights was 80~93 μm, mainly composed of extremely fine sand. The particle size frequency curve showed a single peak distribution, and the sand dust composition was simple, mainly composed of local sand sources. [Conclusion] The sediment transport on the leeward side of the natural P. euphratica riparian forest in the study area was lower than that of the windward side. Average particle size was smaller and sorting performance was better on the leeward side than on windward side. The average particle size smaller than that of the windward side, the sorting was better than that of the windward side, the kurtosis was narrower than that of windward side, and skewness is slightly smaller than that of the windward side. The P. euphratica riparian forest exhibited obvious windbreak and sand fixation benefits, and can be used as an effective measure to reduce the damage by wind and sand transport in the study area.

Copyright of Bulletin of Soil & Water Conservation is the property of Bulletin of Soil & Water Conservation Editorial Office 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 Colorado River has flowed across the dextral strike-slip plate boundary between the North American and Pacific plates since the latest Miocene or earliest Pliocene. The Fish Creek-Vallecito Basin (FCVB) lies on the Pacific Plate in southern California, dextrally offset from the point where the modern Colorado river enters the Salton Trough; it contains a record of ancestral Colorado River sedimentation from 5.3–2.5 Ma. The basin stratigraphy exhibits a changing balance between locally derived (L-Suite) and Colorado River (C-Suite) sediments. This paper focuses on the Palm Springs Group (PSG), a thick fluvial and alluvial sequence deposited on the upper delta plain (between 4.2–2.5 Ma) when the Colorado was active in the area, allowing the detailed examination of the processes of sediment mixing from two distinct provenance areas. The PSG consists of three coeval formations: 1) Canebrake Conglomerate, a basin margin that has coarse alluvial fan deposits derived from surrounding igneous basement; 2) Olla Formation, fan-fringe sandstones containing L-Suite, C-Suite, and mixed units; and 3) Arroyo Diablo Formation, mineralogically mature C-Suite sandstones. Stratigraphic analysis demonstrates that the river flowed through a landscape with relief up to 2000 m. Satellite mapping and detailed logging reveal a variable balance between the two suites in the Olla Formation with an apparent upward increase in L-Suite units before abrupt cessation of Colorado sedimentation in the basin. Stable heavy mineral indices differentiate L-Suite (high rutile:zircon index: RZi 40–95) from C-Suite (RZi: 0–20). Both suites have garnet:zircon index (GZi) and apatite:tourmaline index (ATi) mostly above 50, although many L-suite and mixed Olla samples have much lower ATi (20–50), suggesting that the distal floodplain was wet and the local sediment had a longer residence time there, or went through several cycles of erosion and redeposition. Heavy mineral analysis, garnet geochemical analysis, and detrital zircon U-Pb age spectra allow us to quantify the amount of mixing from different sediment sources. These data show that about 30% of the mixed units are derived from the Colorado River and that up to 20% of the L-Suite is also derived from the Colorado River, suggesting that there was mutual cannibalisation of older deposits by fluvial channels in a transitional area at the basin margin. Although this study is local in scope, it provides an insight into the extent and nature of sediment mixing in a two-source system. We conclude that most 'mixing' is actually interbedding from separate sources; true mixing is facilitated by low subsidence rates and the rapid migration of fluvial channels. [ABSTRACT FROM AUTHOR]

Recently uplifted, highly erodible rocks, and recurrent high intensity storms, generate exceedingly high erosion and sedimentation rates in the East Coast Region (Tairāwhiti) of Aotearoa New Zealand. Despite the recent nature of the Anthropocene record in global terms (∼650 years since Māori arrival, 250 years of colonial impacts), human disturbance has profoundly altered evolutionary trajectories of river systems across the region. Here we document catchment-by-catchment variability in anthropogenic signature as geomorphic river stories for five catchments (Waiapu, Hikuwai, Waimatā, Waipaoa, Mōtū). We show how targeted, fit-for-purpose process-based rehabilitation programmes that manage at source and at scale are required to facilitate river recovery in each of these catchments. The largest rivers in the region, Waiapu and Waipaoa, comprise steep, highly dissected terrains that are subject to recurrent hillslope failures, including systemic shallow landslides, occasional deep-seated rotational slumps and earthflows. Localised sediment input from large (>10 ha) gully mass movement complexes overwhelms valley floors. Targeted revegetation programmes are required to reduce extreme sediment inputs from these sources. Although there are fewer gully complexes in the Hikuwai, multiple landslips supply vast volumes of fine-grained sediment that aggrade and are recurrently reworked along channel margins in lowland reaches. Waimatā has no gully complexes and a smaller number of landslips, but large areas are subject to sediment input from earthflows. The terrace-constrained flume-like nature of this system efficiently flushes materials ‘from the mountains to the sea’, recurrently reworking materials along channel banks in a similar manner to the lower Hikuwai. Systematic reforestation in the middle-upper catchment and revegetation of riparian corridors is required to reduce sedimentation rates in these catchments. In contrast, terraces buffer sediment delivery from hillslopes in the upper Mōtū catchment, where a bedrock gorge separates large sediment stores along upper reaches from the lower catchment. As reworking of valley floor sediments in response to bed incision and reworking (expansion) of channel margins is the primary contemporary sediment source in this system, bed control structures and revegetation of riparian corridors are required as part of targeted sediment management plans. We contend that geomorphic river stories provide a coherent platform for Anthropocene rehabilitation strategies that work with the character, behaviour and evolutionary trajectories of river systems. Although this generic lens can be applied anywhere in the world, we highlight particular meanings and implications in Aotearoa New Zealand where such thinking aligns directly with Māori values that respect the mana (authority), mauri (lifeforce) and ora (wellbeing) of each and every river.

Two field campaigns in Dafeng and Jianggang were organized to compare spatial variations of hydrodynamic characteristics and sediment transport patterns on intertidal flats of different types with distinct human interferences along middle Jiangsu coast, China. The major contributors to the different patterns of sediment dynamics between the two tidal flats were offshore tidal current field and human interference. Offshore tidal force provide the basic setup of tidal current patterns on tidal flats, which is then modified by local morphology. Seawalls parallel to coast reduce tidal flat width, forcing tidal energy to dissipate within a shorter distance and thus influencing tidal flat morphology. Seawalls vertical to coast and major tidal current significantly reduce tidal current speed, which favors sediment deposition on tidal flats. Two seawalls built on both sides of the observational tidal flat profile caused much reduced current speed at Dafeng tidal flat, comparing to the offshore station. Being exposed to offshore radial tidal currents, hydrodynamics at Jianggang was much stronger than that at Dafeng. Residual currents at both areas showed net landward transport at the lower flat and net seaward transport at the upper flat, in favor to sediment accumulation at the middle flat. Sediment flux over tidal cycles showed net landward sediment transport at Dafeng, and net seaward transport at Jianggang, consistent with the convex-up accretion-dominated profile observed at Dafenge, and concave-up erosion-dominated profile observed at Jianggang. The instantaneons sediment flux changed significantly due to variations in velocity and sediment concentrations, but these terms counteracted with each other within tidal cycles, leading to the dominant role of Eulerian flux in determining net sediment flux over tidal cycles. [ABSTRACT FROM AUTHOR]

Paleo-relief reconstruction in source-to-sink system analysis is currently a hot topic in sedimentology, playing an important role in understanding regional tectonic evolution, climate change, surface weathering, sediment supply, and their interrelationships, and it is a key component of source paleogeographic reconstruction. Source areas in deep time are not well preserved due to later tectonic destruction, weathering, and denudation, making it difficult to reconstruct paleo-relief. The BQART sediment flux model depicts the relationship between sediment flux, bedrock lithology, river discharge, drainage area, maximum relief, and annual average temperature in an exorheic setting. When sediment flux and other parameters are acquired from the sedimentary record, maximum relief can be calculated using the BQART model. Through integration of lithofacies paleogeography, cyclostratigraphy, paleohydrolog-ical and paleogeomorphological relationship methods, a BQART model-based approach is proposed for paleo-relief reconstruction in deep time and, based on quantitative paleogeographic reconstructions, and uplift amplitudes and rates can be calculated by employing the sediment-volume backfilling method. Based on this approach, the inner zone of the Emeishan Large Igneous Province (ELIP) was estimated to be rising slowly during the Late Permian, reaching more than 200 m at the end of the Permian, with total tectonic uplift estimated as 500-750 m. This comprehensive analysis demonstrates that deep-time paleo-relief reconstruction approaches are suitable for a middle-large exorheic basin with a warm and humid paleoclimate, which is of great significance for the exploration and development of mineral resources in energy-rich basins. [ABSTRACT FROM AUTHOR]

Copyright of Acta Sedimentologica Sinica is the property of Acta Sedimentologica Sinica Editorial Office 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 Colorado River has flowed across the dextral strike-slip plate boundary between the North American and Pacific plates since the latest Miocene or earliest Pliocene. The Fish Creek-Vallecito Basin (FCVB) lies on the Pacific Plate in southern California, dextrally offset from the point where the modern Colorado river enters the Salton Trough; it contains a record of ancestral Colorado River sedimentation from 5.3–2.5 Ma. The basin stratigraphy exhibits a changing balance between locally derived (L-Suite) and Colorado River (C-Suite) sediments. This paper focuses on the Palm Springs Group (PSG), a thick fluvial and alluvial sequence deposited on the upper delta plain (between 4.2–2.5 Ma) when the Colorado was active in the area, allowing the detailed examination of the processes of sediment mixing from two distinct provenance areas. The PSG consists of three coeval formations: 1) Canebrake Conglomerate, a basin margin that has coarse alluvial fan deposits derived from surrounding igneous basement; 2) Olla Formation, fan-fringe sandstones containing L-Suite, C-Suite, and mixed units; and 3) Arroyo Diablo Formation, mineralogically mature C-Suite sandstones. Stratigraphic analysis demonstrates that the river flowed through a landscape with relief up to 2000 m. Satellite mapping and detailed logging reveal a variable balance between the two suites in the Olla Formation with an apparent upward increase in L-Suite units before abrupt cessation of Colorado sedimentation in the basin. Stable heavy mineral indices differentiate L-Suite (high rutile:zircon index: RZi 40–95) from C-Suite (RZi: 0–20). Both suites have garnet:zircon index (GZi) and apatite:tourmaline index (ATi) mostly above 50, although many L-suite and mixed Olla samples have much lower ATi (20–50), suggesting that the distal floodplain was wet and the local sediment had a longer residence time there, or went through several cycles of erosion and redeposition. Heavy mineral analysis, garnet geochemical analysis, and detrital zircon U-Pb age spectra allow us to quantify the amount of mixing from different sediment sources. These data show that about 30% of the mixed units are derived from the Colorado River and that up to 20% of the L-Suite is also derived from the Colorado River, suggesting that there was mutual cannibalisation of older deposits by fluvial channels in a transitional area at the basin margin. Although this study is local in scope, it provides an insight into the extent and nature of sediment mixing in a two-source system. We conclude that most ‘mixing’ is actually interbedding from separate sources; true mixing is facilitated by low subsidence rates and the rapid migration of fluvial channels.

Assessing rivers' and hillslopes' sensitivity to external forcing is paramount to understand landscape evolution, in particular as a response to Quaternary climate changes. River networks are usually considered to be the main conveyors of environmental signals, such as changes in precipitation, temperature, or baselevel. Yet because hillslopes provide the source of sediment for river networks, their response to environmental change also modulates landscape dynamics. In order to characterize such behavior, we analyze the response times of a transport‐limited hillslope. We use simple numerical models of denudation to study hillslope responses to oscillatory forcing and understand their filtering effects on environmental signals. Modifications in the frequency of climate oscillation, such as the change that occurred at the Mid‐Pleistocene Transition, can significantly modulate hillslope sediment‐flux response. We infer a wide range of hillslope responses, ranging from negligible change over the full range of climate‐forcing frequencies, to a significant filtering of long‐period signals. Plain Language Summary: Landscapes are constituted of hillslopes and rivers where different types of erosion and sediment transport processes take place. Due to their large extent, river networks are an important driver of global landscape response to climatic or tectonic changes. Hillslopes have smaller dimensions but are also where most sediment production occurs and for that reason it is important to have a good understanding of how they respond to perturbations. We use simple numerical models of hillslope evolution to study the influence of oscillating changes of either the efficiency of sediment transport across the hillslope or the rate of channel downcutting at its base. Our results indicates that the period of oscillations for these perturbations controls the amplitude of the sediment flux response out of the hillslope, and provide a framework to understand how this landscape component reacts to climatic cycles such as the glacial/inter‐glacial oscillations of the Quaternary. For example, a major change occurred 800 ka ago with a shift in climate oscillation from 40 to 100 ka period. Our models suggest that in some landscapes this change in period alone could have induced a significant decrease in the amplitude of hillslope sediment flux response. Key Points: A complex hillslope dynamics is associated with the linear to nonlinear sediment flux transitionHillslopes filtering potential of external signals is highly contrasted depending on the type of forcingChanges in the climatic signal frequency at the Mid‐Pleistocene Transition could induce a significant shift in hillslope erosional response [ABSTRACT FROM AUTHOR]

Vegetation colonization is known as an effective process for stabilizing talus slopes, but little quantitative data is available about the relationships between vegetation, sediment fluxes, and sediment storage. The results of a detailed analysis of a single active fine-grained scree slope show that the upper section, scattered with shrubby vegetation, represents an environment characterized by strong biogeomorphic feedbacks. Engineering species (Thuya occidentalis, Betula papyrifera , Cornus sericea, Salix caprea) are well adapted to high sediment mobility with different modes of reproduction and survival. White cedar has a high sediment trapping capacity (>22 m3 per individual) and generates a micro-relief of 80 cm on average. It is responsible for 99 % of the volume of sediment trapped by shrub vegetation, even though it represents 44 % of the total shrub population sampled. In contrast, the hardwoods species have a very low capacity for sediment trapping (<1 m3 per individual) and micro-relief generation (>20 cm). This is likely due to the morphology of the growth which, despite a strong capacity to produce stump rejections, remains limited in trapping sediment. The shrubby vegetation directly influences the trajectory of frost-coated clast flows, the dominant slope process. Nevertheless, the vegetation appears to be quite resilient and stable on a decadal scale, where even the occurrence of extreme debris flows had little impact. In the downslope section, the debris flows, frost-coated clast flows, and snow avalanches present original and circumstantial modalities of tree-line regression. If the upper slope remains of sufficient size to allow for the occurrence of high-magnitude geomorphic events, the tree line appears to be driven primarily by slope processes rather than climate. Although it may be surprising that recent warming lowers the tree line on the studied talus slope, this provides new insight into the complex and non-linear relationships between vegetation and talus slope processes. • Shrub vegetation on active scree provides strong biogeomorphic feedbacks. • White cedar has a high sediment trapping capacity compared to hardwood species. • Engineering species are adapted to sediment mobility for reproduction and survival. • Mass-wasting processes present circumstantial modalities of tree-line regression. • Tree line is driven primarily by slope processes rather than climate. [ABSTRACT FROM AUTHOR]

Retrogressive thaw slumps (RTS) are an important landform of rapid permafrost degradation in regions with very high ground ice contents. RTS mobilize significant amounts of sediment, meltwater and organic carbon and impact downstream hydrological systems by directly affecting topography and water quality. The term megaslump has previously been coined for RTS exceeding 20 ha in size. The Batagay megaslump in the Yana highlands of NE Siberia with an area of 87.6 ha (in 2023, including the bowl-shaped part and the erosional outlet) has been identified as the largest megaslump on Earth. We use very high resolution remote sensing from satellite data and drones, geological structure modeling, and field data to assess how much and what material is thawed and mobilized in the Batagay megaslump. The total volume of permafrost thaw and material loss from the Batagay RTS amounts to about 1 million m3 per year. The material is by one third composed of thawed sediments and by two thirds of melted ground ice. About 4000 to 5000 tons of previously permafrost-locked organic carbon is released every year. Organic carbon content has been measured as Total Organic Carbon (TOC) of sediments and as Dissolved Organic Carbon (DOC) of ground ice. From its formation in the 1970s until 2023, the Batagay RTS – due to thermal denudation and headwalls retreat – mobilized a total volume of about 34.7 million m3 of which 23.4 million m3 were melted ground ice and 11.3 million m3 were thawed deposits including a total of about 169,500 t organic carbon. With these rates of sediment and carbon mobilization, the Batagay megaslump is not only a prominent local feature of rapid permafrost thaw, but offers excellent conditions to study rates and mechanisms of rapid permafrost degradations and to calculate the stock and release of, e.g., organic matter. • 3D geological modeling allowed estimating the Batagay megaslump material flux. • The megaslump mobilized ca. 35 million m3 since initiation in the 1990s. • Since 2014, the annual mobilized volume amounts to ca. 1 million m3/year. • About ⅔ of the total material volume was ground ice and ⅓ was permafrost sediments. • Organic carbon release amounts to 4000 to 5000 tons per year. [ABSTRACT FROM AUTHOR]

Many arid grassland communities are changing from grass dominance to shrub dominance, but the mechanisms involved in this conversion process are not completely understood. Aeolian processes likely contribute to this conversion from grassland to shrubland. The purpose of this research is to provide information regarding how vegetation changes occur in an arid grassland as a result of aeolian sediment transport. The experimental design included three treatment blocks, each with a 25 × 50 m area where all grasses, semi-shrubs, and perennial forbs were hand removed, a 25 × 50 m control area with no manipulation of vegetation cover, and two 10 × 25 m plots immediately downwind of the grass-removal and control areas in the prevailing wind direction, 19° north of east, for measuring vegetation cover. Aeolian sediment flux, soil nutrients, and soil seed bank were monitored on each treatment area and downwind plot. Grass and shrub cover were measured on each grass-removal, control, and downwind plot along continuous line transects as well as on 5 × 10 m subplots within each downwind area over four years following grass removal. On grass-removal areas, sediment flux increased significantly, soil nutrients and seed bank were depleted, and Prosopis glandulosa shrub cover increased compared to controls. Additionally, differential changes for grass and shrub cover were observed for plots downwind of vegetation-removal and control areas. Grass cover on plots downwind of vegetation-removal areas decreased over time (2004-2007) despite above average rainfall throughout the period of observation, while grass cover increased downwind of control areas; P. glandulosa cover increased on plots downwind of vegetation-removal areas, while decreasing on plots downwind of control areas. The relationships between vegetation changes and aeolian sediment flux were significant and were best described by a logarithmic function, with decreases in grass cover and increases in shrub cover occurring with small increases in aeolian sediment flux.

Minimizing wind erosion on agricultural fields is of great interest to farmers. There is a general understanding that vegetation can greatly minimize the wind erosion taking place. However, after harvest, a low vegetation cover can be inevitable, whereby the amount of stubble that remains on a field is dependent on the crop type and land management. This study aims at quantifying the vulnerability to wind erosion of different crops, and the possibility to predict the vulnerability based on high precision aerial images. The study area was the semi-arid Free State, which holds large intensive agriculture on sandy soils. These croplands have been identified as the largest emitter of dust in South Africa. The main crop in the region is maize, but also sunflower, peanut and fallow fields are common land-use types. On these fields, the horizontal sediment flux, the saltation threshold, and aerodynamic roughness length were measured, and the soil cover was assessed using Unmanned Aerial Vehicle (UAV) imagery. The results showed a strong relationship between the soil cover and the sediment flux, whereby fallow and groundnut fields have the highest wind erosion risk. These results emphasize the great importance of soil cover management to prevent wind erosion.

Creeks are essential for salt marshes by conveying water and sediment through this geomorphic system. In this paper, we investigate the mechanisms that determine the residual sediment flux using measurements conducted in tidal creeks in salt marshes of the Yangtze Estuary. A main creek and a secondary creek were studied to explore whether the mechanisms determining residual sediment fluxes through the main creek differ from those in the secondary creek. Measurements in creeks were carried out over 5 years, spanning different months. Sediment import was found during most tides, both in the main creek and the secondary creek, implying that creeks in Chongming generally function as a conveyor belt of sediment into the marsh. However, sediment export can occur during certain overbank tides. When comparing the role of creeks in drainage and sediment delivery, the main creek functions more in delivering sediment while the secondary creek primarily serves as a drainage conduit. To better understand the mechanisms behind sediment fluxes, the residual sediment flux was compared with the residual discharge and the sediment differential (differences in sediment concentration between flood and ebb). Overbank tides generally lead to a net outward discharge as more water from saltmarshes can be concentrated into the marsh creek during ebb tides. This net outward discharge tends to export more sediment during ebb tides. However, due to the sediment abundance during the flood phase in the turbid environment, sediment import can be expected even with the residual export of water. Export of sediment was only found for the few tides with a net outward discharge and a small positive sediment concentration differential. Large negative sediment differentials (larger averaged suspended sediment concentration during ebb tides) have not been observed because the sediment supply during ebb is limited. This paper unravels how the sediment differential and residual discharge contribute to the residual sediment flux, providing a better understanding of sediment dynamics in marsh creek systems. • The relative importance of asymmetries in sediment concentration and in flow for residual sediment fluxes was explored. • The main creek is mainly a conduit for sediment delivery whereas the secondary creek is mainly a drainage conduit. • Sediment supply limitation can even occur in a turbid system like Chongming. [ABSTRACT FROM AUTHOR]

The Indus River is Asia’s longest river, having its origin in the Tibet Mountain northwest of Pakistan. Routed from northern Gilgit and flowing to the plains, the river passes through several provinces and is connected by numerous small and large tributaries. The river was formed tectonically due to the collusion of the Indian and Eurasian plates, which is referred to as the Indus suture Plains zone (ISPZ). The geological setting of the study area is mainly composed of igneous and metamorphic rocks. The river passed through a variety of climatic zones and areas, although the predominant climate is subtropic arid and sub arid to subequatorial. Locally and globally, anthropogenic activities such as building, dams, and water canals for irrigation purposes, mining exploration, and industries and factories all affected the physical and chemical behaviors of the sediments in various rivers. The main effect of human activities is the reworking of weathered soil smectite, a chemical weathering indicator that rises in the offshore record about 5000 years ago. This material indicates increased transport of stronger chemically weathered material, which may result from agriculture-induced erosion of older soil. However, we also see evidence for the incision of large rivers into the floodplain, which is also driving the reworking of this type of material, so the signal may be a combination of the two. Sediments undergo significant changes in form and size due to clashing with one another in the high-charge river.

Wind erosion and resultant dust emissions create significant risks for land degradation and ecosystem health in arid and semi-arid regions. In these regions, fallowing constitutes a major component of conventional agriculture. The present study was conducted to determine wind erosion quantities and agricultural activity-induced mass transport from fallow lands and to assess the correlations of mass transport with climate and soil characteristics. Experiments were conducted over the fallow lands of two adjacent agricultural enterprises (Altinova and Gözlü, Turkey). Sediment flux was measured with passive traps in wet and dry seasons (QtWET and QtDRY). Mass transport in wet and dry seasons was respectively measured as 11.38 and 11.40 kg/ha in Altinova and as 31.61 and 19.71 kg/ha in Gözlü. Both the differences between mass transport of the enterprises and the differences between QtWET and QtDRY of each enterprise were found to be significant (P < 0.05). Pearson's correlation analysis for the correlations of mass transport with soil characteristics revealed significant correlations with electrical conductivity and soil lime content (r = 0.721 and -0.635) (P < 0.05). Total mass transport from the fallow lands of both enterprises throughout a 7-month period of measurement was estimated at 600 t. Based on current findings it was concluded that fallowing should be abandoned and sustainable soil and land management practices from conventional agriculture like minimum tillage or crop rotations should be introduced.

Airborne sediment fluxes were measured in southern Tunisia on two experimental plots tilled with a moldboard and a tiller plough, respectively, during five wind erosion events of different intensities. The sediment fluxes were sampled on both plots using a mast equipped with seven sand traps positioned between ≈10 and 120 cm height. The windblown sediment fluxes in the 0–100 cm layer were about eight times higher on the plot tilled using the tiller plough compared to the plot tilled using the moldboard plough due to different efficiencies in the trapping of the saltating particles in the furrow, depending on the ridges characteristics. On both plots, sediment fluxes of larger particles were depleted in the sediment samplers compared to the proportions measured in the soil from which they were derived. When examining the sediment flux in the 30–100 cm layer, we observed that the efficiency of the vertical transfer was about twice higher on the moldboard plot than on the tiller one. This implies that a higher fraction of the sediment mobilized by wind can be transported over long distances in the case of a surface ploughed with a moldboard. This result could reduce in part the benefit of using the moldboard instead of the tiller plough regarding soil loss by wind erosion.

The present study outlines major concerns and potential environmental consequences of the proposed Pancheshwar high dam in Uttarakhand (Central Himalaya), India. We evaluate the risks associated with the project in the light of environmental impact observed for the Tehri project in the region and the geological understanding developed over the years. Three major factors and their likely impacts analysed relate to (i) sediment mobilization from glacial-paraglacial zones and unstable slopes, (ii) infrastructure development, and (iii) seismicity. We highlight the need to reassess geo-environmental implications of the project in the ecologically sensitive Kaliganga valley. [ABSTRACT FROM AUTHOR]

In present time the intensification of erosion processes is global feature of coastal zone and the most rapid and significant changes are characteristic for accumulative coasts. The features of the sea coast dynamics of the Hong Ha River delta (Vietnam) during last 100 years are analyzed in presented paper. The Hong Ha River delta coast modern dynamics is characterized by combination of accumulation processes near delta mouths and wave erosion between its. The main factors determining the modern dynamics of the delta sea coast are the wave activity with the surge-tidal fluctuations and solid runoff reduction. Current coastal construction cannot protect populated areas from flooding. Reorientation to the integrated coast construction which includes the beaches is realized. Control of Hong Ha river delta coastal erosion is difficult and long-range objective in the framework of the integrated coastal management.

The collection of papers entitled “Annually Laminated Lake Sediments” illustrates the recent progress made in varved sediment research and highlights the variety of methodological approaches and research directions used. The contributions cover the monitoring of modern sediment fluxes using sediment traps, geochronological and sedimentological analyses of varves, multi-proxy investigations, including geochemical and biological proxies, as well as spatiotemporal analyses based on multi-core studies supported by satellite images. The scientific issues discussed the influences of hydroclimatological phenomena on short-term changes in sediment flux, the relationships between biogeochemical processes in the water column and the formation of varves, the preservation of environmental signals in varves, and possibilities of synchronizing varved records with other high-resolution environmental archives.

Abstract The impact of wind waves and salt marsh erosion on sediment transport dynamics of macro-tidal estuarine systems has been examined using a numerical model. Morphological changes associated with salt marsh erosion facilitate the propagation of waves to the marsh edges, and increase the resuspension and export of sediments from the estuary. Results also highlight the impact of tidally-modulated changes in wave action upon sediment transport dynamics throughout a tidal cycle and from neap to spring tide. In particular, wave action at the landward margin of the estuary is limited by the shallow water depth, and tidally induced increments in water depth only cause a modest increase in wave shear stresses. At the seaward side of the domain, the impact of waves is limited by the deeper water, and tidally induced water level variations have a more significant control on wave shear stresses. The outcomes contribute new insights that are important for the sediment budget of macro-tidal estuaries facing climate change and have implications for the long-term morphological evolution of estuarine wetlands. Highlights • Enhanced sediment export from estuaries caused by wind waves • Enhanced salt marsh erosion caused by wind waves • Salt marsh erosion due to morphological changes of estuaries • Wave impact changes with varying water depth [ABSTRACT FROM AUTHOR]

This study focuses on the contrasted architectural elements of the two late Pleistocene alluvial fill sequences (T1 and T2 attributed to the Late Saalian and Weichselian) of the upstream Seine River alluvial plain, la Bassée , and constitutes the first estimation of the sediment volumes associated to these glacial cycles along this river. Estimations of the incised valley and valley fill spatial distribution are obtained by cokriging of data from 546 wells collected from the French national repository and a digital elevation model (DEM) of the present topography. The well stratigraphic attribution is given by the homogenised geomorphological map of la Bassée . We calculated the sediment volume of eroded material for the T1 sequence to be 1.70 10 9  m 3 and of valley fill deposits to be 1.18 10 9  m 3 . This corresponds to a mean thickness of 6.1 m. By contrast, volumes of the T2 sequence are one-third smaller, 1.23 10 9  m 3 . The T2 mean thickness is very similar with 5.8 m. The alluvial plain is divided into four reaches representing a typical assemblage of the T1 and T2 incision style and valley fill deposits. Along the downstream reaches (1 - Montereau-Bazoches, 2 - Bazoches-Grisy), the T2 proportion per kilometer are close to the alluvial plain mean value (reach 1: 76%; reach 2: 69%, la Bassée : 71%), the T2 mean incised valley width corresponds to three quarters of the T1 (4 km). In the middle upstream reach (3 - Grisy-Courceroy), the T2 proportion is the largest (92%), the T2 mean incised valley width is the largest and comparable to the T1 (5.5 km). Along the upstream reach (4 - Courceroy-Romilly), the T2 proportion is the lowest (53%) and the T2 incised valley (2 km wide) is enclosed within the T1 incised valley (4 km wide). The rate of exported material, though, is the same for each sequence in any reach (31%). The spatial pattern of the T1-T2 deposits coincides largely with the presence of a knickpoint along the T2 paleothalweg (downstream part of reach 4, slope face 1.5‰), suggesting that the knickpoint had a large influence on the fluvial processes. The toe of the knickpoint (reaches 3 to 1, slope 0.24‰) was the site of the most efficient erosion of the T1 deposits. We propose that the change of slope favored diversion of the channel path. Upstream of the knickpoint face (upstream part of reach 4, thalweg slope 0.34‰), the incision processes were dominated by incision, avulsions or multithreading with limited lateral migration as indicated by the numerous T1 relicts preserved across valley. The sediment export corresponds to a mean incision rate of 40 m/Ma during the last 300 kyr; a fairly low value for the Paris basin, suggesting a low uplift area north of the Massif Central. Such contrast between the fluvial processes during the T1 and T2 sequences is most likely to be looked for in the climatic conditions that existed at the onset of the incision as no local controls for the knickpoint location could be identified such as active faults, substrate heterogeneity, or flow modifications. The lower sediment flux and the knickpoint associated to the T2 sequence suggest a transient river profile and valley incision at the end of the climatic transition associated to the Weichselian (T2). [ABSTRACT FROM AUTHOR]

Floc'h, F.; Aziayibor, K.; Almar, R.; Du Penhoat, Y.; Lefebvre, J-P.; Dorel, M., and Delacourt, C., 2018. Origin of sediment fluxes in inner shelf zone via acoustic measurements, Grand Popo, Bénin. In: Almar, R.; Almeida, L.P.; Trung Viet, N., and Sall, M. (eds.), Tropical Coastal and Estuarine Dynamics. Journal of Coastal Research, Special Issue No. 81, pp. 107–113. Coconut Creek (Florida), ISSN 0749-0208. In the Gulf of Guinea, energetic swells generated in South Atlantic are responsible for one of the most important littoral drifts in the world, directed Eastward. The construction of harbour dams along this littoral disturbs the natural balance of the system and causes extreme erosion up to 10 m/year. Within the framework of this study, a serie of intensive measurements was conducted at Grand Popo from March, the 10th to the 19th, 2014. A large number of hydrodynamic, sedimentary and morphological parameters were measured. The backscatter signal from an Acoustic Doppler Current Profiler (ADCP) colocalised with a turbidity meter is inverted emprirically. Three main events of suspension over the whole water column are observed, during intense wind (>5m/s) lasting more than 8 hours. Actually, the water surface entrains after about 3–4 hours of intense wind, then the momentum is advected to the bottom in 2 or 3 hours depending on the intensity of the wind. The turbidity is then directly linked to the bottom stress derived from the mean current. The longshore flux is thus due to wind and always Eastward. The cross-shore flux is alternatively directed onshore or offshore. During spring tide, the offshore flux is in phase with the beginning of the tide flow. The exact origin of the current was not identified. Longshore flux were found to be 20 times higher than cross-shore flux. [ABSTRACT FROM AUTHOR]

ABSTRACT Wang, J.; Qu, Z.; Xu, Z.; Shim, J.S.; Liang, B., and Lee, D.Y., 2018. Measurement of Sediment Concentration of the Oscillatory Flow in the Surf- and Swash-zone.. In: Shim, J.-S.; Chun, I., and Lim, H.S. (eds.), Proceedings from the Symposium (ICS) 2018 (Busan, Republic of Korea). Journal of Coastal Research, Special Issue No. 85, pp. 1231–1235. Coconut Creek (Florida), ISSN 0749-0208. The sediment transports near the bed need to be accurately observed to validate the existing models that are based on the empirical formula for the sediment flux and to develop more realistic morphology prediction model. One of the essential tasks for the evaluating the existing models and developing new one is the precise measurement of the sediment transport at swash zone without disturbing flow. Different methods in estimating the sediment transport rates at the surf-zone and swash-zone such as measuring the time evolution of the bed profile, sand ripple volume and migration speed are investigated and evaluated. To develop more reliable estimation of the sediment flux by measuring the vertical profiles of sediment concentration and velocity without disturbing the flow conditions, method of estimation of the vertical sediment concentration profile by detecting the backscattered light intensity using high quality camera was tested and evaluated. The problems of different methods in estimating the sediment flux are identified and discussed. [ABSTRACT FROM AUTHOR]

ABSTRACT Tao, J.; Xu, F.; Yao, P.; Zhou, Z., and Zhang, C., 2018. The variations of sediment transport patterns in the radial sand ridges along the Jiangsu coast, China over the last 30 years. In: Shim, J.-S.; Chun, I., and Lim, H.S. (eds.), Proceedings from the International Coastal Symposium (ICS) 2018 (Busan, Republic of Korea). Journal of Coastal Research, Special Issue No. 85, pp. 216–220. Coconut Creek (Florida), ISSN 0749-0208. The research objective is to clarify the primary factors lead to the variations of the suspended sediment transport in the radial sand ridges (RSRs) along the Jiangsu Coast over the last 30 years. The suspended sediment concentration (SSC) fields measured in several field surveys from 1980 to 2010 were analyzed. The field data indicate that the SSCs in 1980 are higher than those 2010. A two-dimensional numerical model was developed to simulate the inter-annual variations of the suspended sediment transport. Generally, the magnitude of the SSC is highly relevant with the current speed, which peaks around the Old Yellow River Delta (OYRD) and in the central RSRs. However, the northern part of the RSRs indicates higher SSC than the southern part, which is attributed to their different bed sediment composition. The net suspended sediment flux was calculated. In the north of the RSRs, the sediments are transported in the south direction, which implies a sediment input from the OYRD to the RSRs. In the south of the RSRs, a net sediment loss was observed, which is consistent with the decreasing of the sediment flux from the Yangtze River. The simulated suspended sediment transport in 1980 and 2010 mutually show similar spatial patterns, while SSCs in 1980 are overall larger than those in 2010. It is concluded that the decrease of the SSCs from 1980 to 2010 is attributed to the reduction of the OYRD and the large-scale reclamation along the Jiangsu coast, while the sediment fluxes from the Yangtze River is less important. [ABSTRACT FROM AUTHOR]

The Manawatu incised-valley estuary was rapidly infilled between 12,000–4700 cal. yr BP. A combination of empirical measurements of sedimentation rates, a reconstruction of relative sea-level (RSL) change, and digital elevation models of key surfaces within the Holocene sedimentary fill of the valley were integrated to produce a numerical model to investigate the influence of the system controls of sea-level change, sediment flux, and accommodation space on the rapid infilling history of the palaeo-estuary. The numerical model indicates that sediment flux into the palaeo-estuary was greatest during the Holocene marine transgression between 12,000–8000 years BP. The average rate of sediment deposition in the estuary during this period was ~ 1.0 M m 3 yr − 1 . This rapid rate of sedimentation was controlled by the rate of accommodation space creation, as regulated by the rate of sea-level rise and the antecedent configuration of the valley. By the time sea levels stabilised c. 7500 cal. yr BP, the palaeo-estuary had been substantively infilled. Limited accommodation space resulted in rapid infilling of the central basin, though sediment flux into the estuary between 7100 and 4500 cal. yr BP was at a lower rate of 234,000 m 3 yr − 1 . The limited accommodation space also influenced hydrodynamic conditions in the estuarine central basin, driving export of fine-grained sediment from the estuary. Once the accommodation space of the estuarine basin was infilled sediment bypassed the system, with a consequent reduction in the sedimentation rate in the valley. More accurate partitioning of the sources of sediment driving the infilling is necessary to quantify sediment bypassing. Post-depositional lowering of RSL index points from the valley is driven by neotectonics and sediment compaction. [ABSTRACT FROM AUTHOR]

In the second half of the 19th century, channelization of large multi-thread rivers such as the Rhine, the Danube, and the Rhône rivers induced artificial disconnection of most of their secondary channels. Compared to naturally abandoned channels, terrestrialization (i.e., the passage from the aquatic to the terrestrial stage, controlled by sediment deposits and/or lowering of the water level) patterns and rates of such artificially prematurely abandoned channels remain largely unknown. Moreover, factors controlling their evolutionary trajectories are complex owing to a set of pressures occurring throughout the 20th century within specific space-time windows. Through a case study of the Rhône River, this paper aims to assess and distinguish the effects of a set of potential controlling factors on abandoned channel terrestrialization dynamics and lifespan. We tested the influence of: (i) submersible embankments closing the entrance of abandoned channels, (ii) main channel degradation following its channelization or the water level lowering due to channel bypassing in the middle of the 20th century involving drastic water abstraction in these reaches, (iii) transverse dykes within the abandoned channels, (iv) the flooding regime of abandoned channels (i.e., frequency and magnitude of upstream connections producing lotic functioning), and (v) longitudinal variation in the suspended sediment concentration along the main channel. To this end, we studied 24 abandoned channels (16 artificially disconnected at their upstream end by submersible embankments and eight naturally disconnected by bar plug establishment) from the mid-19th to the beginning of the 20th century. Their terrestrialization rates were characterized through the reconstruction of their planimetric trajectories using historical maps and aerial photos. The results reveal a much longer lifespan of artificial abandoned channels compared to natural ones because of the truncation of the initial bedload infilling phase due to the artificial and imposed closing of their entrance. Moreover, terrestrialization occurred faster when water level lowering or channel degradation was greater. Surprisingly, terrestrialization rates were the highest in the most frequently connected artificial abandoned channels (i.e., channels with a high frequency of lotic functioning), probably in relation to the roughness induced by the presence of transversal dykes. Finally, it is difficult to rank all the factors tested because of their complex combinations, which can change in space and time. [ABSTRACT FROM AUTHOR]