Real River Research Articles

Fortified Dual-Spectral Overlap with Enhanced Colorimetric/Fluorescence Dual-Response Immunochromatography for On-Site Bimodal-Type Gentamicin Monitoring.

Immunochromatography (ICA) remains untapped toward enhanced sensitivity and applicability for fulfilling the nuts and bolts of on-site food safety surveillance. Herein, we report a fortified dual-spectral overlap with enhanced colorimetric/fluorescence dual-response ICA for on-site bimodal-type gentamicin (Gen) monitoring by employing polydopamine (PDA)-coated AuNPs (APDA) simultaneously serving as a colorimetric reporter and a fluorescence quencher. Availing of the enhanced colorimetric response that originated from the PDA layer, the resultant APDA exhibits less required antibody and immunoprobes in a single immunoassay, which facilitates improved antibody utilization efficiency and immuno-recognition in APDA-ICA. Further integrated with the advantageous features of fortified excitation and emission dual-spectral overlap for the Arg/ATT-AuNCs, this APDA-ICA with a "turn on/off" pattern achieves the visual limits of detection of 1.0 and 0.5 ng mL-1 for colorimetric and fluorescence patterns (25- and 50-fold lower than standard AuNPs-ICA). Moreover, the excellent self-calibration and satisfactory recovery of 79.03-118.04% were shown in the on-site visual colorimetric-fluorescence analysis for Gen in real environmental media (including real river water, an urban aquaculture water body, an aquatic product, and an animal byproduct). This work provides the feasibility of exploiting fortified dual-spectral overlap with an enhanced colorimetric/fluorescence dual response for safeguarding food safety and public health.

Covalent organic framework with extraordinary intrinsic catalytic activity for electrochemical sensing of iodide ions

Environmental conservation and food safety have aroused enormous concerns owing to their close relationship with human health. Iodide ion (I−) could result in serious diseases in mankind. Thus, it is challenging and essential to develop an effective approach to capture and detect I−. Herein, the TT-COF(Zn) material prepared using 2,3,6,7-tetra (4-formyl phenyl) tetrathiafulvalene (TTF) and 5,10,15,20-tetrakis(para-aminophenyl) porphyrin Zinc (II) (TPZ) as building blocks were designed directly as electrode modified material for electrochemical sensing of I−. Combining the meritsofTPZ and TTF to construct the intrinsic efficient electron-transfer pathways, as well as the advantages of porous channel and single-site catalysis of COF, TT-COF(Zn) material-modified electrode showed excellent electrocatalytic performance towards the redox reaction of I−, which makes it a sensitive sensing platform for the electrochemical quantification of I−. After a series of optimization experiments, the I− sensor demonstrated a wide linear range (0.02–15 mM), low detection limit (3.15 μM), as well as other good sensing features. The proposed sensor also performed well in the determination of I− in real river samples. This work not only offers a simple method to assay I− effectively but also paves a way for the strategical design and synthesis of COFs for electrochemical sensing applications.

Stable and efficient microbubble-enhanced cold plasma activation for treatment of flowing water

Cold plasma technology has received immense attention in several fields including wastewater treatment, disinfection, food processing and storage, and agriculture due to its ability to produce reactive species at low energy input. However, the scalability of generation of plasma activated water (PAW) still remains a challenge. A microbubble-enhanced cold plasma activation (MB-CPA) technology leverages small bubbles for effectively interfacing plasma discharge in a gas phase and a flow of liquid media. In this study, we develop a stable and efficient approach for the continuous production of PAW by maximizing the transfer of active species generated during plasma discharge to water flow. Novel Venturi-type microbubble generators were designed for the production of PAW by maximizing the rapid transfer of active species generated during plasma discharge in air. Key geometrical features of the tubes including the position and the opening size of the air inlet were tuned, aiming to transfer active species in a wide range of liquid flow conditions. The performance of our flow systems was evaluated by using pure water, buffered saline, and real river water containing micro-pollutants. We found that MB-CPA can effectively eliminate chemical compounds such as dye and antibiotic residues, as well as biological pathogens like Gram-positive and Gram-negative bacteria. In a cell viability assay, the technology exhibited cytotoxic effects against cancerous cells, specifically HeLa and MCF-07 cell lines. This multi-functionality underscores the versatility of MB-CPA, positioning it as a multifaceted solution for both water and wastewater treatment. Our work shows that the designed MB-CPA system represents a promising and sustainable technological advancement, offering a green alternative for the widespread activation of water in various applications.

W-WaveNet: A multi-site water quality prediction model incorporating adaptive graph convolution and CNN-LSTM.

Water quality prediction is of great significance in pollution control, prevention, and management. Deep learning models have been applied to water quality prediction in many recent studies. However, most existing deep learning models for water quality prediction are used for single-site data, only considering the time dependency of water quality data and ignoring the spatial correlation among multi-sites. This research defines and analyzes the non-aligned spatial correlations that exist in multi-site water quality data. Then deploy spatial-temporal graph convolution to process water quality data, which takes into account both the temporal and spatial correlation of multi-site water quality data. A multi-site water pollution prediction method called W-WaveNet is proposed that integrates adaptive graph convolution and Convolutional Neural Network, Long Short-Term Memory (CNN-LSTM). It integrates temporal and spatial models by interleaved stacking. Theoretical analysis shows that the method can deal with non-aligned spatial correlations in different time spans, which is suitable for water quality data processing. The model validates water quality data generated on two real river sections that have multiple sites. The experimental results were compared with the results of Support Vector Regression, CNN-LSTM, and Spatial-Temporal Graph Convolutional Networks (STGCN). It shows that when W-WaveNet predicts water quality over two river sections, the average Mean Absolute Error is 0.264, which is 45.2% lower than the commonly used CNN-LSTM model and 23.8% lower than the STGCN. The comparison experiments also demonstrate that W-WaveNet has a more stable performance in predicting longer sequences.

Insights into interfacial S-scheme/bulk type II dual charge transfer mechanism enabling silver oxide/N-rich carbon nitride anti-photocorrosion and enhanced photoactivity

Infectious diseases, such as COVID-19, continue to pose a significant threat to global public health and economics. This study establishes a one-of-a-kind heterojunction catalyst with a built-in electric field and enhanced structural defects, allowing for the formation of interfacial S-scheme and bulk type-II dual charge transfer channels, as demonstrated by extensive experimental investigation and density functional theory calculations. This unique property greatly enhances the photogenerated electron/hole pair separation and transfer, producing more active species in Ag2O/C3N5 for water disinfection, which inactivation efficiency of E. coli is around 7.0 folds for pure C3N5 and 1.5 folds for Ag2O. The spatial separation of photogenerated e-/h+ pairs and the tendency of O2/H2O molecules to be reduced or oxidized at the interface enable excellent anti-photocorrosion. Exceptional disinfection of real lake and river water, along with exceptional stability and reusability, demonstrate the practical application potential. This work is pivotal for the theoretical development of sophisticated photocatalytic systems.

Electrochemical detection of sulfanilamide using tannic acid exfoliated MoS2 nanosheets combined with reduced graphene oxide/graphite

Sulfonamides are a family of synthetic drugs with a broad-spectrum of antimicrobial activity. Like other antimicrobials, they have been found in aquatic environments, making their detection important. Herein, an electrochemical sensor was designed using tannic acid exfoliated few-layered MoS2 sheets, which were combined with a mixture of reduced graphene oxide (rGO) and graphite flakes (G). The rGO/G was formed using electrodeposition, by cycling from −0.5 to −1.5 V in an acidified sulfate solution with well dispersed GO and G. The exfoliated MoS2 sheets were drop cast over the wrinkled rGO/G surface to form the final sensor, GCE/rGO/G/ta-MoS2. The mixture of rGO/G was superior to pure rGO in formulating the sensor. The fabricated sensor exhibited an extended linear range from 0.1 to 566 μM, with a LOD of 86 nM, with good selectivity in the presence of various salts found in water and structurally related drugs from the sulfonamide family. The sensor showed very good reproducibility with the RSD at 0.48 %, repeatability and acceptable long term stability over a 10-day period. Good recovery from both tap and river water was achieved, with recovery ranging from 90.4 to 98.9 % for tap water and from 83.5 to 94.4 % for real river water samples.

'The very term mensuration sounds engineer-like': measurement and engineering authority in nineteenth-century river management.

Measurement was vital to nineteenth-century engineering. Focusing on the work of the Stevenson engineering firm in Scotland, this paper explores the processes by which engineers made their measurements credible and explains how measurement, as both a product and a practice, informed engineering decisions and supported claims to engineering authority. By examining attempts made to quantify, measure and map dynamic river spaces, the paper analyses the relationship between engineering experience and judgement and the generation of data that engineers considered to be 'tolerably correct'. While measurement created an abstract and simplified version of the river that accommodated prediction, this abstraction had to be connected to and made meaningful in real river space despite acknowledged limitations to measuring practice. In response, engineers drew on experience gained through the measuring process to support claims to authoritative knowledge. This combination of quantification and experience was then used to support interventions in debates over the proper use and management of rivers. This paper argues that measurement in nineteenth-century engineering served a dual function, producing both data and expertise, which were both significant in underpinning engineering authority and facilitating engineers' intervention in decision making for river management.

The formation and adsorption mechanism studies of 3D hydrangea-like ZnFe-LDHs/FeOOH for the highly efficient removal of phosphate

Phosphate in water can cause a series of problems such as overgrowth of algae and other aquatic organisms, foul-smelling, turbid water and lower dissolved oxygen concentrations, thereby posing a serious threat to human health and environment. To efficiently remove phosphate from water, three-dimensional hydrangea-like ZnFe-layered double hydroxides/FeOOH composites (3D hydrangea-like ZnFe-LDHs/FeOOH) were designed and prepared by a facile urea hydrothermal method. The maximum adsorption capacity of phosphate by 3D hydrangea-like ZnFe-LDHs/FeOOH reached about 200 mg·g−1, much higher than that of ZnFe-LDHs prepared by co-precipitation method (53 mg·g−1) and other reported adsorbents, which confirmed that 3D morphology contributed to the improvement of adsorption capacity. Time-dependent experiments were designed to explore the formation mechanism of 3D hydrangea-like structure and the results indicated directional aggregation and epitaxial growth were two main processes. Batch experiments were conducted to investigate adsorption behavior of phosphate. The adsorption kinetics and isotherms showed that the adsorption process followed the quasi-first-order kinetics and Langmuir model. Besides, 3D hydrangea-like ZnFe-LDHs/FeOOH could be regenerated effectively and recycled at least three times. 3D hydrangea-like ZnFe-LDHs/FeOOH possessed fascinating performance in phosphate removal from real river samples and laundry detergent samples, with the removal rates of 66–100 % and 80–100 %, respectively. Furthermore, 3D hydrangea-like ZnFe-LDHs showed good adsorption performance towards other anionic dyes, including Congo Red and Orange Yellow II, with the maximum adsorption capacity of 867 mg·g−1 and 225 mg·g−1, indicating its widespread applicability. The adsorption mechanism of phosphate by 3D hydrangea-like ZnFe-LDHs was furtherly investigated, mainly containing metal coordination, anion exchange between layers and electrostatic interactions.

High energy facet-dominated TiO2−X facet heterojunction with excellent carrier utilization for ultrasensitive SERS sensing and efficient degradation of antibiotic residues

Realizing efficient utilization of photogenerated carriers is crucial to boosting the photophysical and photochemical performances of semiconductors. Herein, (101) and (001) facets co-exposed anatase TiO2−X facet heterojunction with abundant oxygen vacancies was developed as a new surface-enhanced Raman scattering (SERS) substrate and also as an excellent photocatalyst for synchronous detection and degradation of antibiotic residues in actual water system. Due to the efficient carrier separation induced by facet heterojunction and the efficient charge migration derived from exposure of more high energy (001) facets, the TiO2−X facet heterojunction exhibits an ultrahigh SERS enhancement factor of 1.07 × 107 for non-resonant Raman probe, with excellent spectral reproducibility and stability. More meaningfully, the developed substrate can realize an ultrasensitive detection for different kinds of antibiotic residues in real river water, even a comprehensive identification for multicomponent residues. Moreover, TiO2−X facet heterojunction can also execute an efficient photocatalytic degradation for residue pollutants in actual water system. And, the developed multi-function substrate possesses an excellent recyclability not only in SERS detection but also in photocatalysis.

Novel electrochemical sensing strategy for ultrasensitive detection of tetracycline based on porphyrin/metal phthalocyanine-covalent organic framework

In this work, a novel two-dimensional semiconducting metal covalent organic framework (CuTAPc-TFPP-COF) was synthesized and used as biosensing platform to construct aptasensor for trace detection of tetracycline (TC). The CuTAPc-TFPP-COF integrates the highly conjugated structure, large specific surface area, high porosity, abundant nitrogen functional groups, excellent electrochemical activity, and strong bioaffinity for aptamers, providing abundant active sites to effectively anchor aptamer strands. As a result, the CuTAPc-TFPP-COF-based aptasensor shows high sensitivity for detecting TC via specific recognition between aptamer and TC to form Apt-TC complex. An ultralow detection limit of 59.6 fM is deduced from the electrochemical impedance spectroscopy within a wide linear range of 0.1–100000 pM for TC. The CuTAPc-TFPP-COF-based aptasensor also exhibits good selectivity, reproducibility, stability, regenerability, and excellent applicability for real river water, milk, and pork samples. Therefore, the CuTAPc-TFPP-COF-based aptasensor will be promising for detecting trace harmful antibiotics residues in environmental water and food samples.

Waste cellulose acetate-based dynamic membrane for NOM-containing river water filtration

Excessive leaching of natural organic matter (NOM) from swamp forests into water resources poses significant challenges for water treatment plants, primarily due to its high variability. In this study, a waste-based cellulose acetate (W-CA) membrane was explored as a dynamic membrane for the filtration of real river water containing NOM and compared to a commercial-based CA (C-CA) membrane. The membranes were fabricated and thoroughly characterized. The results revealed that the W-CA membrane exhibited greater hydrophilicity, as indicated by a static contact angle of 84°, compared to the hydrophobic nature of the C-CA membrane (104°). The mean pore diameters of the C-CA and W-CA membranes were 4.4 µm and 5.3 µm, respectively, suitable as the base for a dynamic filter. The formation of a dynamic cake filtration layer (identified mainly as humic and fulvic acids) was confirmed from visual observation, SEM image and the decrease in the pore sizes. It was further validated from the cake layer as the dominant fouling mechanism obtained from a curve fitting analysis. Despite the W-CA and C-CA membranes respectively showed a high steady-state river water permeabilities of 348 and 226 L/(m2 h bar) respectively, they were still unable to fully remove NOM (27% removal for W-CA and 39% removal for C-CA membrane), suggesting the necessity for further developments. This study underscores the potential of W-CA membranes for water treatment while promoting a circular economy by converting waste into valuable resources and sustainable products.

Concave microlens arrays with tunable curvature for enhanced photodegradation of organic pollutants in water: A non‐contact approach

AbstractSolar‐driven photodegradation for water treatment faces challenges such as low energy conversion rates, high maintenance costs, and over‐sensitivity to the environment. In this study, we develop reusable concave microlens arrays (MLAs) for more efficient solar photodegradation by optimizing light distribution. Concave MLAs with the base radius of μm are fabricated by imprinting convex MLAs to polydimethylsiloxane elastomers. Concave MLAs possess a non‐contact reactor configuration, preventing MLAs from detaching or being contaminated. By precisely controlling the solvent exchange, concave MLAs are fabricated with well‐defined curvature and adjustable volume on femtoliter scale. The focusing effects of MLAs are examined, and good agreement is presented between experiments and simulations. The photodegradation efficiency of organic pollutants in water is significantly enhanced by 5.1‐fold, attributed to higher intensity at focal points of concave MLAs. Furthermore, enhanced photodegradation by concave MLAs is demonstrated under low light irradiation, applicable to real river water and highly turbid water.image

Low‐Friction Graphene Oxide‐Based Ion Selective Membrane for High‐Efficiency Osmotic Energy Harvesting

AbstractGraphene‐based laminate membranes with selective ion‐transport capability show great potential in renewable osmotic energy harvesting. One of the great challenges is to reduce the overall energy barriers while remain the high ion selectivity in the transmembrane ion transport process. Here, a strategy is proposed to break the trade‐off between ion selectivity and permeability in laminar nanochannels using amphiphilic molecules as modifier, which enhances the surface charge density of nanochannel by loading more ion polymer with polar head and lows the frictional force of ion transport with hydrophobic tail. The conversion efficiency can reach to 32% in osmotic energy harvesting (0.5 m/0.01 m concentration gradient) after adopting this modifier. During the process of mixing real river water and seawater, the maximum power density can reach to 13.38 W m−2. The amphiphilic molecules also bind adjacent nanosheets, endowing the membrane's strong mechanical strength and high stability in aqueous solution. This work can open up a new way to regulate the transmembrane ion transport in 2D laminate membranes.

Development of High-Precision Urban Flood-Monitoring Technology for Sustainable Smart Cities.

Owing to rapid climate change, large-scale floods have occurred yearly in cities worldwide, causing serious damage. We propose a real-time urban flood-monitoring technology as an urban disaster prevention technology for sustainable and secure smart cities. Our method takes advantage of the characteristic that water flow is regularly detected at a certain distance with a constant Doppler velocity within the radar observation area. Therefore, a pure flow energy detection algorithm in this technology can accurately and immediately detect water flow due to flooding by effectively removing dynamic obstacles such as cars, people, and animals that cause changes in observation distance, and static obstacles that do not cause Doppler velocities. Specifically, in this method, the pure flow energy is detected by generating a two-dimensional range-Doppler relation map using 1 s periodic radar observation data and performing statistical analysis on the energy detected on the successive maps. Experiments to verify the proposed technology are conducted indoors and in real river basins. As a result of conducting experiments in a narrow indoor space that could be considered an urban underpass or underground facility, it was found that this method can detect flooding situations with centimeter-level accuracy by measuring water level and flow velocity in real time from the time of flood occurrence. And the experimental results in various river environments showed that our technology could accurately detect changes in distance and flow speed from the river surface. We also confirmed that this method could effectively eliminate moving obstacles within the observation range and detect only pure flow energy. Finally, we expect that our method will be able to build a high-density urban flood-monitoring network and a high-precision digital flood twin.

Development and Characterization of a Molecularly Imprinted Polymer for the Selective Removal of Brilliant Green Textile Dye from River and Textile Industry Effluents.

In this paper, we present an alternative technique for the removal of Brilliant Green dye (BG) in aqueous solutions based on the application of molecularly imprinted polymer (MIP) as a selective adsorbent for BG. The MIP was prepared by bulk radical polymerization using BG as the template; methacrylic acid (MAA) as the functional monomer, selected via computer simulations; ethylene glycol dimethacrylate (EGDMA) as cross-linker; and 2,2'-azobis(2-methylpropionitrile) (AIBN) as the radical initiator. Scanning electron microscopy (SEM) analyses of the MIP and non-molecularly imprinted polymer (NIP)-used as the control material-showed that the two polymers exhibited similar morphology in terms of shape and size; however, N2 sorption studies showed that the MIP displayed a much higher BET surface (three times bigger) compared to the NIP, which is clearly indicative of the adequate formation of porosity in the former. The data obtained from FTIR analysis indicated the successful formation of imprinted polymer based on the experimental procedure applied. Kinetic adsorption studies revealed that the data fitted quite well with a pseudo-second order kinetic model. The BG adsorption isotherm was effectively described by the Langmuir isotherm model. The proposed MIP exhibited high selectivity toward BG in the presence of other interfering dyes due to the presence of specific recognition sites (IF = 2.53) on its high specific surface area (112 m2/g). The imprinted polymer also displayed a great potential when applied for the selective removal of BG in real river water samples, with recovery ranging from 99 to 101%.

Magnetic nanocellulose-based adsorbent for highly selective removal of malachite green from mixed dye solution

Herein, a novel magnetic adsorbent (BC/AA/MN@Fe3O4) was successfully prepared from waste bamboo fiber tissue and montmorillonite, and subsequently applied for the highly selective removal of malachite green (MG, removal efficiency = 97.3 %) from the mixed dye solution of MG with methyl orange (MO, removal efficiency = 4.5 %). The magnetic adsorbent has a high porosity with abundant mesopores. In the single dye MG solution, the adsorbent could effectively remove MG over a wide pH range from 4 to 10, and the maximum adsorption capacity (qmax) was 2282.3 mg/g. Moreover, the magnetic adsorbent could remove MG from various solutions including mixed dye solution, high salinity solution, and real river water dye solution. The thermodynamic results proved that the adsorption process of MG was spontaneous and endothermic. The adsorption of MG was due to the comprehensive effects of electrostatic attraction, hydrogen bonding interactions and ions exchange, between the adsorbent and MG. Furthermore, the BC/AA/MN@Fe3O4 exhibited an excellent reusability with adsorption efficiency above 53.4 % after five consecutive cycles. Therefore, the prepared magnetic nanocellulose-based adsorbent was expected to be a promising material for highly selective adsorption and separation of MG from mixed dye solution.

Photocatalytic fuel cell self-powered sensor for Cu2+ detection in water and soil: Signal amplification of biomass induced carbon-rich carbon nitride photoanode

The development of an accurate, selective, sensitive, and quantitative monitoring method for copper ion (Cu2+) in water and soil is crucial for addressing environmental pollution. Herein, a photocatalytic fuel cell self-powered sensor (PFC-SPS) platform was proposed by carbon-rich carbon nitride photoanode for Cu2+ determination. Carbon-rich carbon nitride is formed by replacing nitrogen atoms of tertiary nitrogen with carbon generated through the thermal decomposition of biomass chitosan. The carbon-rich structure enhances the π delocalization in the carbon nitride skeleton, improving the optical absorption and accelerating the transmission of charge, endowing the photoanode with high and stable output signal. The formed Cu2+-aptamer complex increases the surface resistance of electrode, hindering the catalytic reaction of H2O2 oxidation and leading to the decrease in the output power density signal. This PFC-SPS platform detected Cu2+ with a wide range of 1.0 ∼ 1.5 × 103 nM, a low limit of 0.40 nM, excellent selectivity, stability and accuracy for real river water and agricultural soil samples. It is expected that the platform can achieve low-cost and portable monitoring by a digital multimeter, and this work also proposes a strategy for detecting heavy metal ions based on the synergism of a photocatalytic fuel and self-powered platform.

Bottom-up strategy of multi-level structured boron-doped diamond for the durable electrode in water purification

Long-term exposition of electrodes to aqueous media inevitably results in biofouling and adhesion of bacteria, reducing the electrolysis efficiency of electrodes for water treatment. To ensure technically efficient antifouling of materials for durable electrodes, hierarchical micro-/nano structured boron-doped diamond (BDD) electrodes were designed and synthesized. Multi-level structured BDD was coated on titanium mesh by a bottom-up strategy, based on a combination of self-assembly seeding and hot filament chemical vapor deposition (HFCVD) growth. The morphology of the BDD coating can be controlled by manipulating the seeding density and boron doping concentration. The designed micro/nano hierarchical structure of the BDD electrode suppressed bacterial adhesion greatly and exhibited excellent anti-biofouling efficiency with an antibacterial rate of ∼ 93 %, which entails simplified self-cleaning and durable BDD-coated electrodes. The BDD-coated electrodes were employed to electrochemically treat Escherichia coli-contaminated water, killing virtually all bacteria (≥99.9 %) in 1 min. Finally, real river water was electrochemically treated, reducing the chemical oxygen demand (COD) down to 5 mg/L in 4 h. The excellent performance shows the great potential of the structured BDD electrodes for long-term water purification.

Ag/Cr-TiO2 and Pd/Cr-TiO2 for Organic Dyes Elimination and Treatment of Polluted River Water in Presence of Visible Light.

In this work, photocatalytic materials constituted by Cr-doped TiO2 (Cr-TiO2) decorated with noble metals show high effectiveness in the mineralization of Acid Orange 7 (AO7) and in the disinfection of real river water. The materials were firstly obtained by sol-gel method to get Cr-TiO2 that was subsequently modified by photochemical deposition of Ag or Pd nanoparticles (Ag/Cr-TiO2, Pd/Cr-TiO2). Chemical-physical characterization results evidenced that the noble metals were homogeneously distributed on the Cr-TiO2 surface. By using Pd(0.25%)/Cr-TiO2, the AO7 discoloration efficiency was about 91.4% after only 60 min of visible irradiation, which can be due to the lowest band gap of this material. Moreover, nitrates, chlorides, total hardness, and coliform bacteria content significantly decreased after the treatment of real river water samples (that is contaminated by industrial and domestic effluents) under UV and visible light irradiation in the presence of TiCrOx decorated with noble metals. One hundred percent of elimination rate for E. coli, total coliforms, and other enterobacteriaceae (without regrowth) was achieved by using Ag/Cr-TiO2 as photocatalyst.

In-situ characterisation of fluvial dune morphology and dynamics under limited sediment supply conditions, Seine River, France

Dune dynamics and associated sedimentary fluxes have been estimated over a period of a week in the river Seine characterised by limited sediment supply. Distributed into two corridors, typical medium and small dunes associated with fluvial environments have been characterised from multibeam data acquired on four dates, 23-29 March 2021, after a limited peak flood. Dune morphometric parameters have been quantified on cross-dune 1 m spacing of bed elevation profiles and dune migration rates have been calculated by analysing successive multibeam acquisitions. Evidence of limited sediment supply conditions have been recognised from areas uncovered by mobile sediment in the troughs between medium dunes. Under such conditions, bedload transport associated with dune migration has been estimated using three methods: differential bathymetry, dune tracking and the Van Rijn empirical formula using a correction factor accounting for limited sediment supply conditions. The three methods provide similar bedload fluxes (less than an order of magnitude difference), and the small differences are related to input data uncertainties and the capability of these methods to capture sediment transport processes, such as sediment bypassing dunes. Based on field observations, this paper brings new constrains to the relationships between dune morphological parameters, migration rates and sedimentary fluxes and environmental parameters (sediment grain size, flow velocity and water depth) under limited supply conditions in a real river.