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Modelling of many real-world processes, such as drug delivery, wastewater treatment, and pharmaceutical production, requires accurate descriptions of the dynamics of hard particles confined in complicated domains. In particular, when modelling sedimentation processes or systems with driven flows, it is important to accurately capture volume exclusion effects. This work applies Dynamic Density Functional Theory to the evolution of a particle density under diffusion, external forces, particle–particle interaction, and volume exclusion. Using a spectral element framework, for the first time it is possible to include all of these effects in dynamic simulations on complex domains. Moreover, this allows one to apply complicated no-flux, and other non-local, non-linear, boundary conditions. The methodology is also extended to control problems, addressing questions of how to enhance production set-up in industrially-motivated processes. In this work the relevant models are introduced, numerical methods are discussed, and several example problems are solved to demonstrate the methods' versatility. It is shown that incorporating volume exclusion is crucial for simulation accuracy and we illustrate that the choice of boundary conditions significantly impacts the dynamics. [ABSTRACT FROM AUTHOR]

Mangrove forests are critical coastal ecosystems that provide great socio‐ecological services, which are also highly vulnerable to climate change, particularly to sea level rise (SLR). Here we assess changes in mangrove forests in four distinct river/tide/wave‐dominant large deltas along the Indo‐Pacific coast based on 1,336 remote sensing images by machine learning techniques. We find that mangroves are migrating seaward at a rate of 18% ± 12% m/yr, which can offset landward mangroves loss, 67% of which caused by land use conversion. The fact that mangroves are expanding seaward with accretion rates exceeding SLR suggests that climate change has not yet triggered substantial loss in deltaic mangrove forests. Assuming that present environmental conditions do not change and that sediment and organic deposition in the deltaic topsets match SLR rates, we project that 90% of deltaic mangrove forests may start to retreat after 132–194 years. Early inundation of mangroves will occur in wave‐dominated delta. Plain Language Summary: Mangrove forests provide significant ecological and societal services, and mitigation global warming. However, large‐scale loss in mangroves could be induced by anthropogenic drivers and sea level rise (SLR). Our study based on deltas along the Indo‐Pacific coast, highlight that mangroves are expanding seaward at a rate of 18% ± 12% m/yr, indicating that there is little impacts from SLR and has not been substantial loss in mangrove forests in these deltas so far. Mangrove expansion here can efficiently offset 67% landward mangrove losses indicates that our new model project that 90% of mangrove shorelines will may start retreating within 132–194 years. We conclude that favoring mangroves expansion seaward would enhance coastal protection and reduce the need of landward mangrove restoration. Key Points: Mangroves along typical deltas are expanding seaward of about 18% ± 12% m/yr, indicating that there is little impacts from sea level riseMangrove expansion here can efficiently offset 67% landward mangrove lossesNew model project that 90% of mangrove fringes may start retreating within 132–194 years, and wave‐dominated delta present early inundation [ABSTRACT FROM AUTHOR]

Notch development at the base of sea cliffs is an important control on cliff recession rates, but a detailed mechanistic understanding of notch formation by swash abrasion is lacking. We conducted physical experiments, using homogeneous erodible rock simulants, to study notch‐forming mechanisms under periodic sediment‐laden bore impacts. Our findings reveal shifts in the temporal dynamics of notch development. Initially, swash uprush and vortex formation contribute to a positive feedback loop that creates a shallow and wide notch. Subsequently, upward erosion ceases, and notch backwear and downwear are dominated by the vortex. Eventually, sediment deposition armors the notch floor; this negative feedback loop reduces erosion. The sediment size determines the amount of erosion, with a range of grain sizes generating maximum erosion. This indicates a dependence on the momentum of the sediment particles entrained within the bore. This research reveals fundamental notch formation mechanisms driven by swash abrasion. Plain Language Summary: When waves attack a rock cliff, they gradually undercut the cliff and remove materials, forming a wave‐cut notch. Studying how notches form and develop in natural settings takes a very long time, so we created a weaker cliff in the laboratory using easily eroded foam. The cliff was exposed to repeated impacts from bores carrying sediment, representing the impact of broken waves. Notch formation is observed over a few hundred hours. Initially, the notch is wide and shallow. As it grows, abrasive sediment cannot be propelled into the roof, stopping the upward expansion of the notch, and sediment piles up at the bottom, blocking further downward erosion. The notch continues to deepen, but at a decreasing rate. The size of the beach sand or gravel has an important influence on the erosion rate. If the sediments are too large or too small, little erosion occurs, whereas sediments of a certain size can cause rapid erosion. This is because waves need to be able to entrain sediment and hurl it with sufficient force against the cliff to cause erosion. Key Points: Controlled laboratory experiments with repeated swash impacts reveal positive and negative feedback mechanisms in abrasion notch formationNotch geometry varies over time and is determined by swash impact location, vortex formation and sediment depositionGrain size modulates beach shape and sediment‐laden bore momentum, collectively influencing notch development [ABSTRACT FROM AUTHOR]

ABSTRACT Present day submarine canyons are active conduits for the transfer of large volumes of sediment, carbon and pollutants from continents to oceans. However, the evolution of submarine canyons over geological timescales remains poorly understood due to their erosional nature and low preservation potential. The Late Cretaceous Punta Baja Formation represents a well‐preserved submarine canyon‐fill that evolved on a tectonically‐active ocean‐facing margin. Exposures provide kilometre‐scale continuous strike and dip sections of the 120 m thick and 1.2 km wide feature. An inherited tectonic fabric influenced the location and orientation of canyon incision into fluvial bedrock. The stratigraphic evolution of the Punta Baja submarine canyon is reconstructed from incision to fill, which shows that it remained an active sediment conduit throughout the time represented by the preserved fill. The depositional architecture of the north–south oriented erosionally confined canyon‐fill is asymmetrical, with sub‐vertically stacked channel‐fills to the west, and an overbank confined by the canyon margin to the east. Sedimentary process interactions led to depositional patterns that are considered distinct to submarine canyon fills. Dynamic topography generated by mass‐wasting processes captured sediment and drove knickpoint development, an autogenic mechanism that modifies sediment delivery to the ocean floor. Widespread upstream dipping surfaces in channel‐fills are interpreted as the stratigraphic expression of upstream migrating supercritical‐flow bedforms, which played an important role in sediment storage and transport in the canyon. The steep relief and internal topography of canyons leads to complicated and characteristic confined overbank flow behaviour and depositional patterns. This study provides insight into how processes that are observed in modern canyons are selectively preserved through the lifetime of the canyon and construct or destroy stratigraphy on geological timescales. [ABSTRACT FROM AUTHOR]

Salt diapirs dominate the structure in many sedimentary basins and control the preservation and migration of hydrocarbon. The formation of salt diapirs generally falls into two endmember models: active (up-building) and passive (down-building) diapirism. In the active model, salt diapirs rise from salt buoyancy to pierce through the sedimentary overburden, whereas in the passive model, salt diapirs result from differential loading of sediments during deposition. These endmember models are mostly conceptual or kinematic, the mechanics of active and passive diapirism and their relative roles and interactions in the formation of salt diapirs remain uncertain. Here, we use two-dimensional high-resolution numerical models to investigate the primary factors and critical conditions for active and passive diapirism. Our results indicate that it is improper to use driving mechanisms to classify salt diapirs, because the buoyancy-driven active salt diapirism involves differential loading, while the passive diapirism requires salt buoyancy. The rise of salt diapirs is more sensitive to the effective viscosity of the overburden than to the salt viscosity. Stiff overburdens could prevent the rise of salt diapirs, but they could be pierced by salt diapirs if plastic yield of the overburden is allowed. During deposition, the coupled salt-sediment deformation, driven by both salt buoyancy and differential loading of sediments, can lead to various diapiric salt structures and minibasins. Regional tectonic stress generally promotes salt diapirism by enhancing strain weakening of salts and overburdens. We suggest that the classification of active and passive salt diapirism is an oversimplification in most cases. We propose a general model of the formation of salt diapirs that usually begins with dome initiation driven by salt buoyancy, followed by syndepositional down-building controlled by sedimentation and differential loading and ends with canopy formation when sedimentation stops. [ABSTRACT FROM AUTHOR]

Utilizing over 31   000 Lg waveforms from 136 crustal earthquakes recorded at 346 regional stations, we conduct detailed tomographic mappings of the Lg Q structure across Eastern Asia in a frequency range from 0.5 to 4.0 Hz. By improving the standard two-station (TS) method, we effectively correct non-unity site response ratios using site responses estimated at individual stations. This innovative approach combines the flexible recording geometry of the TS method with the precision of reversed two-station (RTS) and reversed two-event (RTE) methods, producing a comprehensive data set devoid of source and site effects for Q tomography. To address unsolvable 3-D structural effects in the Lg spectral amplitude modelling, we justify these as modelling errors with a Gaussian distribution. This approach supports our SVD-based tomographic method, allowing for effective inversion of attenuation parameters and quantitative assessment of model resolution and errors. Our results reveal a complex relationship between Lg Q and the tectonic characteristics of Eastern Asia. In well-resolved regions, low Q o (1-Hz Q) values correspond to areas with high heat flow, partial melt, thick sediment and recent tectonic-thermal activities, in contrast to high Q o values in stable, ancient crusts lacking recent tectonic activity. Rift basins are characterized by low Lg Q o, whereas flexural basins generally have high Q o basements. We also note that post-formation factors, such as sedimentation and crustal flow intrusion, significantly impact Q o values. Furthermore, Lg Q shows a complex frequency relationship, though the power-law approximation with positive power η remains useful. The frequency dependence power η is inversely related to Q o: the regions with low Q o typically have high η and vice versa. This study provides reliable attenuation tomographic and relative site response models for Lg waves in Eastern Asia, pertinent for relative geophysical studies. [ABSTRACT FROM AUTHOR]

This study presents a comprehensive analysis of shoreline dynamics in the Thanjavur district, focusing on erosion and accretion trends from 1992 to 2022. The coastal region was partitioned based on Taluk boundaries to discern distinct patterns in erosion and accretion. The Peravurani region displayed stability, while the Mettupalayam Coast exhibited modest accretion, influenced by sediment deposition from the Tedakkiar River. Mettupalayam had the highest net shoreline movement (NSM), contrasting with the Mandiripattinam coast’s prevalent erosion trend. Areas such as Ammani Chattram and Setubava Chattram coast remained relatively stable, while Ganeshapuram, Sendalapattinam, and Sembalpattinam coasts experienced low accretion linked to the Ambuliar River. The study found that the maximum erosion in the study area is 4.1 m/yr (end point rate (EPR)) and 4.21 m/yr (linear regression rate (LRR)) at the Maravakkadu coastal region, and the maximum accretion is 3.75 m/yr (EPR) and LRR of 4.12 m/yr at the Mettupalayam coast. Employing the Kalman filter, future shoreline projections for 2032 and 2042 revealed heightened erosion and accretion trends, identifying vulnerable areas and distinct accretion patterns. It has been predicted that the eastern part of the coastal stretch erodes towards the land, and the western part is accreting. The dynamic interaction of erosion and accretion in Sendalapattinam underscored historical influences on future projections. However, ongoing erosion on the Maravakkadu coast may entail potential economic consequences. The findings emphasize the need for informed coastal management strategies, integrating historical data and future predictions. This will help maintain the coastal ecosystem and community resilience in the changing shoreline dynamics. [ABSTRACT FROM AUTHOR]

Water erosion poses a significant threat to the sustainability of natural resources and hydro-agricultural infrastructure, particularly in the Mediterranean region, including Morocco. The Allal El Fassi watershed faced such challenges and underwent anti-erosion measures between 2008 and 2014. This study aims to evaluate the effectiveness of these measures in mitigating dam siltation within the watershed. The methodologies employed include the utilization of the MUSLE model, optimized with bathymetric surveys of the dam, to estimate the amount of sediment reaching the dam and derive the P-factor associated with the implemented anti-erosion measures. Additionally, the radioisotope technique was utilized to assess erosion rates at managed and unmanaged sites within the watershed. The results obtained using the MUSLE model and bathymetric data revealed a noteworthy reduction in mean annual soil loss within the timeframe of 2002–2010 to 2010–2013, resulting in a 13.9% decrease in sediment reaching the dam. Furthermore, variations in the P-factor of erosion control measures were observed, ranging from 0.31 to 0.52 during the respective periods. Utilizing the radionuclide 7Be, erosion rates ranging from 6.8 to 25.3 t.ha−1 were determined for the studied plots, facilitating the calculation of P-factors for specific erosion control measures. Significantly, gabion check dams displayed a P-factor of 0.47, dry stone barriers had a P-factor of 0.41, fruit trees with basins showed a P-factor of 0.51, and enclosures exhibited a P-factor of 0.67. These findings suggest a causal relationship between the implementation of erosion control measures and the reduction in sedimentation rates at the Allal El Fassi Dam, highlighting the interdependence between the two phenomena. [ABSTRACT FROM AUTHOR]

The morphodynamics of rivers in semiarid environments tend to be controlled by episodic flood events, but the precise nature of sedimentary processes and sediment source areas within catchments affected by episodic floods remains not well understood. This study presents geomorphological, sedimentary and mineralogical data from different river reaches along the semiarid Letaba River within Kruger National Park, northeast South Africa. Geomorphological and sedimentary data were used to evaluate river morphodynamic behaviour and identify the major controls on landform development. Mineralogical data (heavy minerals and trace elements) were examined from surface sediment samples from different river reaches to determine the potential source areas for sediment reworking within the catchment (channel bank, channel bed, tributaries) for flood-transported sediments. Results of this analysis on downstream reaches show catchment-averaged sediment contributions from the channel bed of 42.5%, tributaries of 35%, and channel bank of 22.5%. These sediment contributions likely arise as a result of the different flow conditions experienced in different locations of the river system during floods. However, there is significant variability between samples from individual reaches, likely related to valley width and bedrock vs sediment availability. The contributions of river sediments from different sources are conceptually developed through a model of sediment source variability at different hydrodynamic stages. This highlights the role of floods in reactivating non-perennial tributaries and adding new sediment into the main channel. Measurements of perennial channel storage, therefore, do not give the whole picture of total sediment availability or activation during floods. [ABSTRACT FROM AUTHOR]

The results of the study of bottom sediments and water of the estuary of the Grøndalen River (Grøn-Fjord, West Spitsbergen) are presented. The stratigraphic features of the sedimentary strata are determined. The chronology of changes in geoecological environmental conditions has been established using radioisotope dating methods. The main factors influencing sedimentation in the study area are air temperature and precipitation during the period of predominance of low temperatures. It is shown that climate fluctuations determine the chronological sequence of the sedimentation rate and the change of the lithotype of the bottom sediment toward fine fractions. [ABSTRACT FROM AUTHOR]

In the study of natural waterways, the use of formulas such as Manning's equation is prevalent for analyzing flow structure characteristics. Typically, floodplains exhibit greater roughness compared to the main river channel, which results in higher flow velocities within the main channel. This difference in velocity can lead to increased sedimentation potential within the floodplains. Therefore, accurately determining Manning's roughness coefficient for compound channels, particularly during flood events, is of significant interest to researchers. This study aims to model the Manning roughness coefficient in compound channels with both converging and diverging floodplains using advanced soft computing techniques. These techniques include a multi-layer artificial neural network (MLPNN), Group Method of Data Handling (GMDH), and the Neuro-Fuzzy Group Method of Data Handling (NF-GMDH). For the analysis, a dataset from 196 laboratory experiments was used, which was divided into training and testing subsets. Input variables included parameters such as longitudinal slope (So), relative hydraulic radius (Rr), relative depth (Dr), relative dimension of flow aspects (δ*), and the convergent or divergent angle (θ) of the floodplain. The relative Manning roughness coefficient (nr) was the output variable of interest. The results of the study showed that all the models performed well, with the MLPNN model achieving the highest accuracy, characterized by R² = 0.99, RMSE = 0.001, SI = 0.0015, and DDR = 0.0233 during the testing phase. Further analysis of the soft computing models indicated that the most critical parameters influencing the results were Sr, Rr,Dr*, and θ. These findings highlight the effectiveness of soft computing techniques in accurately modeling the Manning roughness coefficient in complex channel conditions and provide valuable insights for future research and practical applications in the management of flood events and waterway analysis. [ABSTRACT FROM AUTHOR]

Grade control structure (GCS) can be used to reduce erosion in river beds. They decrease the river bed scour by changing the flow regime and reducing its velocity. It is required to maintain the stability of these structures against the scour hole that generates downstream of them, so investigating the scour hole characteristics downstream of the GCS is inevitable. In the present research, the equilibrium scour holes downstream of GCS were investigated under three discharges (q=0.00467, 0.00583, 0.00700 m3/s.m) and two different sedimentation conditions (d50=0.082, 1.6 mm). The results show that in the constant GCS geometry and finer sediment, the maximum scour depth (ds) and maximum scour hole length (ls) increase. In the same sedimentary conditions and different geometry, when the slope of the GCS downstream face varied from 90° to 60°, ds increases, but ls decreases. Also, the hydraulic jump forms on the scour hole at high flow intensity, which has an essential influence on the geometry of the equilibrium scour hole. Comparison of ds/Hc between the present study and Ben Meftah and Mossa (2020) has R2=0.891 and RE=10.66%, which reveals acceptable compatibility between the present study results and previous ones. [ABSTRACT FROM AUTHOR]

The alarming degradation of soils, particularly in the Moroccan Rif region, is the result of various forms of water erosion processes, leading to significant environmental and economic damage in the area. The Oued Lebene watershed is a sub-basin of the Sebou River, located in the central part of the Pre-Rif. Using GIS, remote sensing, and the universal soil loss Equation modified for North African conditions and validated by field observations, this study aimed to measure soil losses, sediment delivery capacity, and sediment yield rates. The estimation of soil loss reveals that the watershed is exposed to a high degree of erosion, reflected by an estimated total annual loss of 6 379 314 t/yr, with an average annual rate of 46.17 t/ha/yr. The severe erosion class covers 52.25% of the study area, contributing to 90.67% of sediment production with an average of 80.11 t/ha/yr-1. The erosion class below the tolerance threshold according to Wischmeier represents 48 108 hectares, or 34.82% of the total watershed area. Analysis of the synthetic sediment delivery ratio (SDR) map shows that the sediment delivery capacity is approximately 0.17, and the sediment yield (SY) in the Oued Lebene watershed is estimated at 770 440.32 t/yr. This is the outcome of the interaction between multiple causative factors, including steep slopes, friable substrates, severely degraded vegetation cover, etc., which increasingly accelerate the degradation of water resources in the downstream Oued Sebou, a source of irrigation for agricultural lands. [ABSTRACT FROM AUTHOR]

The present study discusses flood hazard characteristics in the lower reaches of the West Rapti River based on the results obtained from field surveys and numerical computations using depth averaged 2-D numerical models for flood flow and associated sediment transportation. To evaluate the inundation process with sediment erosion and deposition in the floodplain, a new erosion term was introduced into the mass conservation equations for suspended sediment and bed sediment. The results obtained from numerical computations indicated that field data on the spatial distributions of depths for inundation, and sediment erosion and deposition can be evaluated by the numerical model. Thus, numerical predictions were performed for the inundated areas, and the accumulated volumes of sediment erosion/deposition for floods with return periods of 50, 100, and 200 years, as a step towards damage assessment and risk assessment due to floods with active sediment transportation in the floodplains. [ABSTRACT FROM AUTHOR]

Naumure Multipurpose Project (NMP) featuring a 169 m high Concrete Face Rock Filled Dam (CFRD) is the proposed reservoir project in the West Rapti River with an installed capacity of 218.34 MW. Most of the rivers in Nepal carry significant sediment loads that will consequently catalyze reservoir sedimentation. This phenomenon prevails as the primary factor in reducing reservoirs useful life, making ineffective for both flood control and hydroelectricity generation. Ultimately, such process of sedimentation has adverse impacts on projects economic feasibility and long-term sustainability. Therefore, the objective of this research was to examine the expected sediment deposition pattern in the NMP reservoir throughout its operational period by employing 1D HEC-RAS model to simulate the sedimentation process. The model was simulated for 10, 20, 30, 40 and 50 years. Yang's equation as a sediment transport function, Active layer as a bed sorting method and Toffaleti as a fall velocity method were best suited for the river reach. The delta deposition was formed between 11 km and 22 km upstream of the dam region in the Jhimruk river, with the sediment deposition depth reaching peaks of about 23 m, 38 m, 39 m, 41 m and 49 m in 10, 20, 30, 40 and 50 years, respectively. Similarly, the delta deposition was formed between 13 km and 33 km upstream of dam region in the Madi river, with the sediment deposition depth reaching peaks of about 47 m, 62 m, 60 m, 68 m and 75 m in 10, 20, 30, 40 and 50 years respectively. Headcutting of delta deposition occurred between 20 and 30 year due to high flood during low stage of reservoir. Furthermore, the study revealed that about 6.22%, 11.61%, 15.94%, 22.96% and 25.65% of the storage capacity of NMP reservoir will be depleted in 10, 20, 30, 40 and 50 years respectively. [ABSTRACT FROM AUTHOR]

While the Cretaceous Normal Polarity Superchron has documented instances of brief reversed polarity intervals, the absence of accurate age determinations for such abrupt shifts poses a challenge in leveraging them as reliable reference tiepoints. This study presents a cyclostratigraphic analysis of gamma‐ray data from the DSDP Site 402A. The identification of Milankovitch cycles allowed us to construct a 405‐kyr astronomically‐tuned age model for two reversed events that occurred in the Aptian. Our results estimate an age of 117.03 ± 0.14 Ma for the Chron M"‐1r" or ISEA and 116.17 ± 0.14 Ma for reversal "2," with timespans of ∼20 and ∼10 kyr, respectively. Sedimentation patterns are influenced by orbital eccentricity cycles with an average sedimentation rate of 5 cm/kyr. The short time intervals related to these reversals exposes the difficulty in their detection in cores through paleomagnetic analysis as well as in deep‐tow surveys. Plain Language Summary: The Cretaceous Normal Polarity Superchron (CNPS) was characterized as a "quiet zone," which includes no geomagnetic reversals during ∼38 Myr. A number of studies propose significant fluctuations in geomagnetic intensity, with distinct features observed in paleosecular variations, including periods of reversal events, and the actual occurrence, timespan and ages for these rapid magnetozones have been under debate in literature. This paper provides the age and constrains the timespan of two of these debated reversals (i.e., M"‐1r" or ISEA, and "2") during the CNPS. The determination of the age of the reversals during the CNPS is a fundamental support for global correlations. Key Points: Orbital tuning for M‐1r (ISEA) has an age of 117.03 ± 0.14 Ma and a timespan of 20 kyrThe reversal "2" has an age of 116.16 ± 0.14 Ma and a minimum timespan of 10 kyrDSDP Site 402A has an average 5 cm/kyr sedimentation rate and eccentricity Milankovitch cycles rules sedimentation patterns [ABSTRACT FROM AUTHOR]

Polyhydroxyalkanoates(PHAs) are considered a good alternative to petroleum-based plastics because of their good biodegradability and biocompatibility. The synthesis of PHAs using activated sludge can not only solve the problem of the high cost of pure cultures but also improve the utilization value of activated sludge. In this study, sludge activity recovery experiments were firstly conducted and the effects of different initial sludge concentrations on the activated sludge PHAs synthesis system were further investigated. the initial sludge concentrations were 1#SBR (2800 ± 50) mg/L, 2#SBR (4200 ± 50) mg/L, and 3#SBR (5500 ± 50) mg/L. The results showed that the activity, sedimentation performance and PHAs synthesis capacity of activated sludge were enhanced after the sludge activity recovery experiment. At the initial sludge concentration of 4200 mg/L, the activated sludge PHAs synthesis system was operated stably and the synthesis efficiency of PHAs was enhanced. In contrast, at the initial sludge concentration of 2800 and 5500 mg/L, the steady state of the activated sludge PHAs synthesis system was damaged to different degrees at different times, and the synthesis efficiency of PHAs was greatly reduced. [ABSTRACT FROM AUTHOR]

While the biogeochemical properties of the Israeli coastal shelf (ICS) are similar to adjacent pelagic waters, the external sources of inorganic nitrogen (N) are very different. The main source of 'new' N to the pelagic zone is deep winter mixing, with minor contributions from atmospheric deposition and eddy diffusion across the nutricline. For the ICS, major N sources include offshore water advection (260 × 10⁶ mol N y−¹), atmospheric input (115 × 10⁶ mol N y−¹), and riverine input (138 × 10⁶ mol N y−¹), which primarily consists of treated wastewater and stormwater runoff. Direct pollutant discharge from sewage outfalls and submarine groundwater discharge are relatively minor. Key N sinks are new production (420 × 10⁶ mol N y−¹) and sediment deposition and uptake (145 × 10⁶ mol N y−¹). Inputs of nitrate and ammonium were similar and dominant in winter. Unlike temperate shelves, where riverine input is dominant, here it was only slightly higher than atmospheric input, with net N advection onto the shelf being significant. External N inputs did not change net primary production (NPP) by more than ~30% or affect dominant pico and nanophytoplankton genera, except in localized patches. This study offers baseline values for future climate and environmental change assessments. [ABSTRACT FROM AUTHOR]

Submarine fan reservoirs are important accumulation zones for oil, gas, and natural gas hydrates, offering significant potential for hydrocarbon exploration. During the deposition period of the Sanya Formation in the southern part of the Changchang Sag of the Qiongdongnan Basin, a large submarine fan developed. However, the internal structure, source-sink system, and formation mechanism of this fan remain poorly understood, posing significant challenges to exploration in this area. This paper examines the source-to-sink sedimentary processes and deposition of submarine fans, using the Changchang Sag, in the Qiongdongnan Basin in the Northern South China Sea, as an example, which will provide valuable general guidance for deep water oil and gas exploration. Based on the theories of seismic stratigraphy and seismic sedimentology, this paper utilizes techniques such as seismic facies analysis, seismic attribute optimization, paleogeomorphology reconstruction, and source-to-sink sedimentary systemanalysis to analyze the 3D seismic data of the study area. Research indicates that the Sanya Formation in the Changchang Sag of the Qiongdongnan Basin comprises three depositional units: submarine fan, feeder channel, and Semi-deep marine to deep marine mudstone. The submarine fan is a fan formed by the coupling and convergence of submarine fans sourced from the southwest and southeast. Internally, it is divided into three sub-facies: the proximal fan of the sand-rich submarine fan, the main body of the sand-rich submarine fan lobes, and the distal lobes of the sand-rich submarine fan. The submarine fan sourced from the southwest extends nearly north-south and is primarily fed by sediment transported through three large, banded ancient valleys. The sedimentary filling is characterized by three-phase progradation. The submarine fan sourced from the southeast extends nearly east-west and is primarily fed by sediment transported through a single large, banded ancient valley. The sedimentary filling is characterized by two-phase lateral accumulation. During the deposition period of the Sanya Formation, certain areas of the southern uplift belt were exposed for extended periods and subjected to weathering and erosion. Sediments are transported to large ancient valleys through small supply channels. A large number of sediments were transported to the southern slope of the Changchang sag through the provenance channel system such as large ancient valleys and slope belts and deposited in the center of the sag. These make up a complete system of large ancient uplifts and submarine fan source-to-sink sedimentary systems. The sedimentary model is a lobed submarine fan controlled by semi-restricted ancient valleys and expansive basins. [ABSTRACT FROM AUTHOR]

The northwestern continental margin of the South China Sea, extending from the broad shelf and canyon-growth slope across the Xisha Trough, represents a relic crustal rift that eventually connects to the abyssal plain. However, the provenance and source-to-sink process of sediments in this special topography remains unclear. In this study, we present the detrital zircon U-Pb geochronology of surface sediments from the northwestern margin of the South China Sea to identify the sediment provenance, track the transport pathway, and understand the source-to-sink process in this margin. The results showed that detrital zircons exhibit a wide range of U-Pb ages from 3,062.9 to 41.5 Ma and are characterized by peaks centered on 140–154 Ma, 240–258 Ma, 425–452 Ma, and 738–991 Ma. Statistical analysis indicated that the clastic sediments on the shelf closely resemble those sourced from the Pearl River system. Conversely, sediments on the slope and abyssal plain demonstrated characteristics indicative of multiple sources, primarily originating from the Pearl River, with a minor contribution from the Red River. Further quantitative study revealed a progressive increase (from 8.2% to 43.2%) in the prevalence of Red River-derived sediments with ascending water depth on the shelf and slope, whereas sediment influx in the deepest sector remains predominantly sourced from the Pearl River. This study emphasizes the controls of topography and currents in modulating the transportation of coarse-grained and fine-grained sediments within the sourceto- sink system and provides a favorable solution for reconstructing the sedimentary process in continental margins. [ABSTRACT FROM AUTHOR]

Controlled sediment flushing operations (CSFOs) allow to recover reservoirs storage loss while rebalancing the sediment flux interrupted by dams but, at the same time, may cause unacceptable ecological impact. In this study, we investigated the responses of the food web of an upland stream to a CSFO, focusing on the effects of fine sediment deposition detected in three different mesohabitats, i.e., a pool, a riffle, and a step-pool. The field campaign lasted two years and included repeated measurements of fine sediment deposits, and sampling of periphyton, benthic macroinvertebrates and fishes. A moderate and patchy deposition occurred due to the CSFO with short and medium-term ecological impact on the lower trophic levels of the food web, which may affect the whole ecosystem functioning. The monitoring of all available mesohabitats in the investigated stream allowed to detect variations in the ecological response to CSFO, providing a more adequate assessment of the impact. As expected, sedimentation was larger in the pool but, in contrast to our hypotheses, the impact was lower and the recovery was longer for the benthic organisms inhabiting the riffle. In the case of fishes, no lethal impact of both brown trout and bullhead was recorded in the short term but the occurrence of longer lasting effects could not be excluded. To date, this is one of the few studies dealing with a detailed integrative assessment of the downstream impact of sediment management from reservoir on both abiotic and biotic components of stream ecosystem. [ABSTRACT FROM AUTHOR]

ABSTRACT Saddle dolomite is a Ca–Mg carbonate characterized by curved crystal faces, curved cleavage and sweeping extinction under cross‐polarized light. Saddle dolomite and, generally, Ca–Mg carbonates with curved crystal faces, are often assigned to the burial (hydrothermal) realm and serve as proxy archives for hydrogeochemical processes in sedimentary basins and orogens. At present, the physicochemical conditions leading to the formation of these peculiar warped carbonates are unclear, and the mechanisms inducing the curvature of their crystal lattice are debated. This study uses laboratory experiments to assess the factors controlling the formation of carbonates with curved crystal faces as a function of fluid temperature, reactant size, fluid salinity and fluid Mg : Ca. Results show that a range of magnesium calcites with curved surfaces form at elevated temperatures (ca 220°C) from calcium‐rich fluids (Mg : Ca = 0.43) within a wide range of fluid salinities (5 to 40 wt.%). Magnesium calcites that nucleate epitaxially on rhombohedral or saddle dolomite substrates exhibit warped surfaces, while those that nucleate on calcite seeds form flat surfaces. Although the two crystal habits can co‐occur, Mg‐calcites with curved crystal faces (Mg : Ca of 0.35 to 0.40) tend to be more calcium‐rich than those with flat faces (Mg : Ca of 0.58 to 0.74). In experiments with higher fluid temperature (230°C), calcite reactants undergo replacement by dolomite exhibiting planar crystal faces. The results collectively indicate that the formation of Ca–Mg carbonates with warped surfaces is likely related to a combination of geochemical and physical parameters and various threshold limits, as opposed to one specific parameter, for example, elevated fluid temperature, as is commonly reported in the literature. Although most of the present experimental precipitates are disordered magnesian calcites with bent crystal faces, it is reasonable, at the level of a tentative working hypothesis, that these represent precursors of many ancient saddle dolomites commonly found in burial settings. [ABSTRACT FROM AUTHOR]

The middle and lower reaches of the Jinsha River, which is the upper reach of the Yangtze River in China, play crucial roles in the water security of people living in the middle and lower reaches of the Yangtze River. The construction of 11 dams in this region has significantly altered the aquatic environment. Although researchers have investigated the effects of cascade hydropower station development in the middle and lower reaches of the Jinsha River based on factors such as flow, sediment, and fish, the overall impact of this station on the aquatic environment remains unclear. Therefore, the purpose of this study is to comprehensively investigate the effects of cascade hydropower station development on the aquatic environment based on three factors: river, aquatic organism, and ecosystem factors. In terms of river factors, the development of cascade hydropower stations increases runoff in the dry season and decreases it in the flood season, leading to sediment deposition and water temperature stratification in cascade reservoirs, and changes in water quality. In terms of aquatic organism factors, cascade hydropower development not only changes the species composition but also reduces biodiversity. Effects of ecosystem factors including the ecological flow, value, and landscape as well as sustainability are summarized, with results indicating positive and negative impacts on river ecosystems. Finally, recommendations for future research on the effects of cascade hydropower development on the aquatic environment of rivers are provided. [ABSTRACT FROM AUTHOR]

High-latitude ecosystems have been overlooked in carbon budgets, which traditionally focus on mangroves, salt marshes, and seagrasses. The benthic assemblages and their Nature Contributions to People in Namuncurá – Burdwood Bank I and II, two offshore sub-Antarctic Marine Protected Areas (MPAs), are the conservation values. Here we show that the carbon reservoirs of these MPAs can be greater than those of their Antarctic counterparts, which, together with their extension, emphasize the need to maintain their protected status. Considering their total area, these MPAs stored in biomass 52,085.78 Mg C, corresponding 34,964.16 Mg to organic carbon (OC) and 17,121.62 Mg to inorganic carbon (IC). Surficial sediments stored 933,258,336 Mg C with 188,089,629 Mg of OC and 745,168,707 Mg of IC. However, when accounting for CO2 production through CaCO3 precipitation, the IC fractions decrease to 3,150.37 Mg C and 137,111,042 Mg C for biomass and sediments, respectively. We assume low sediment deposition due to the oceanic location, as direct sedimentation rates for these areas are unavailable. Most blue carbon assessments have focused solely on OC, despite the formation of CaCO3 releases CO2, decreasing net carbon storage. We compared various approaches for incorporating carbonates into carbon estimations. These results underscore the importance of including IC into carbon assessments and highlights the importance of sub-Antarctic benthic ecosystems as nature-based solutions to climate change. [ABSTRACT FROM AUTHOR]

Multiple vortex flow patterns are commonly observed in lateral pumping station forebays, particularly in basins with high sediment concentrations. These patterns can lead to pump blockage, sediment deposition, and other issues that disrupt pump station operations. The water-sediment two-phase flow in lateral pumping station forebays is significantly influenced by the start-up combination, yet our understanding remains limited. To address this, the mixture multiphase flow theory is introduced to describe water-sediment dynamics, and the mathematical model is validated with experimental data. By analyzing the characteristics and formation mechanisms of large vortex and multiple small vortex regions in the original scheme, nine different start-up combination schemes were proposed. The research results indicate that, due to the narrow channel and slope effect in the lateral forebay, some of the gravitational potential energy of the water-sediment mixture is converted into kinetic energy upon entering the forebay, thereby increasing the velocity in the main flow area. Additionally, due to the friction and dissipation effects of the two sidewalls, a pressure difference is generated in the main flow area, resulting in the formation of multi-level vortices. Furthermore, the various types of proposed start-up combinations can optimize the flow patterns in the forebay to a certain extent. The preferred scheme improved the uniformity of flow velocity by 18.63% and increased the deviation angle by 17.62°, resulting in a 75.47% reduction in vortex area compared to the original scheme. These research results provide theoretical guidance for optimizing start-up combinations and reorganizing flow field structures to achieve hydrodynamic dredging effects. [ABSTRACT FROM AUTHOR]

In light of the forebay of a lateral pump station in Shaanxi Province, numerical simulation and engineering tests were employed to analyze the correlation between the formation of multiple vortices and sediment deposition in the lateral forebay. Building upon this foundation, a total of 24 distinct rectification measures were proposed to scrutinize the alteration in flow regime within the lateral forebay, followed by an engineering test to validate the optimal scheme in the absence of rectification measures. The findings from the engineering test of the lateral forebay were consistent with the outcomes of the numerical simulation. This marked the inaugural proposition of a trapezoidal array clapboard within a lateral forebay. By adjusting the position, rotating the clapboard angle, and selecting the optimal scheme 24, the flow velocity uniformity at section C1-2 reached 93.16%, the deflection angle measured 94.32°, and the vortex area reduction rate was 87.73%, significantly mitigating the vortex impact on this section. Within section C1-3, the flow velocity uniformity attained 96.58%, the deflection angle measured 86.43°, and the vortex area reduction rate in this section amounted to 81.26%. Through the analysis of these two sections, the scheme's accuracy was validated. Additionally, the sediment deposition thickness decreased by 2.39 m under scheme 24, thus ensuring favorable operational conditions for the inlet forebay of the lateral pump station. [ABSTRACT FROM AUTHOR]

Laboratory studies, which field trial was conducted in the 2020-2021 growing season at the Eastern Mediterranean Agricultural Research Institute, were conducted at Gümüşhane University. In this study, the findings showed that urea was used as the top fertilizer in different growth stages of the 'Yakamoz' bread wheat cultivar used as material, and the effects of urea application periods and flour type, on the quality traits, such as dry matter, ash, protein, acidity, fresh and dry gluten, gluten index, sedimentation, and falling number were investigated. For this purpose, in addition to the control application, tillering, stem elongation, milky and dough stages were chosen as urea application periods. Laboratory studies were carried out in randomized plots using the split-plot design with three replications. In the present study, all quality traits showed statistically significant differences for urea application periods; these values were ranged as follows: Dry matter: 90.20-90.77%, ash: 1.037-1.213%, protein: 14.01-15.15%, acidity: 0.037- 0.056%, wet gluten: 41.49-43.67%, dry gluten: 14.75%-15.46, gluten index: 69.28-80.38%, sedimentation: 20.0-21.0 mL, late sedimentation: 23.5-29.8 mL and falling number: 753.8-881.7 s. In addition, other quality parameters except dry matter, protein and sedimentation changed statistically for flour type. Accordingly, whole wheat flour for ash (1.443%), acidity (0.051%) and gluten index (82.53%); white flour showed high values for wet (44.90%) and dry (15.96%) gluten, late sedimentation (35.60 mL) and falling number (836.4 s). As a result, while applying urea as a top fertilizer, it is recommended to choose the stem elongation stage for high gluten index, delayed sedimentation and protein, and the dough maturity stage for high dry matter. It would be appropriate to represent more genotypes and different nitrogen sources in further studies to be more inclusive. [ABSTRACT FROM AUTHOR]

The occurrence and abundance of Astrospartus mediterraneus (Risso, 1826) have significantly increased in the last three decades in several areas of the Mediterranean Sea. In the Tavolara–Punta Coda Cavallo Marine Protected Area (NE Sardinia, Tyrrhenian Sea, Mediterranean Sea), 60 specimens were observed mainly on the granitic shoals of the Tavolara Channel, an area characterized by very intense currents and high sedimentation. The basket stars were mainly found living as epibionts of gorgonians (Eunicella verrucosa, Paramuricea clavata and Leptogorgia sarmentosa) and massive sponges (Spongia officinalis, S. lamella, Sarcotragus foetidus). We also documented 21 small specimens (3–20 mm in diameter of the oral disc) observed in June 2024 between 27 and 52 m depth on E. verrucosa and P. clavata colonies. The bimodal size-frequency distribution of these specimens suggested that, probably, specimens belong to two different reproductive events occurring in spring 2023 and 2024. [ABSTRACT FROM AUTHOR]

In recent years, Conversational Analysis (CA) has seen an increasing interest in longitudinal studies (Deppermann & Pekarek Doehler, 2021). The recurrent experience of interactional practices leads interactants to develop routines that may sediment into entrenched patterns over time (Dreyer, 2022). Longitudinal CA thus aims to track the emergence and sedimentation of interactional practices over time. In this contribution, we analyse interactional practices of participation in play-situations. Participation in joint activities is a universal form of human sociality (Goodwin & Goodwin, 2005). Here, we focus on how children perform their own agentive participant's work and how mothers support their children in doing so. Investigating a longitudinal data set of mother-child play-interactions at ages 1 and 5, we ask whether participation patterns emerge as early as in the first year and are sedimented in the fifth year, as well as whether the synchronisation of embodied action provides crucial resources for the achievement of active participation in joint activities. [ABSTRACT FROM AUTHOR]

We use the complex model combining the spatially 2D bottom material transport model, the 3D suspension transport model, and the 3D hydrodynamics model. The results of numerical experiments obtained on the basis of a complex model for calculating sedimentation and changes in the relief of the bottom surface are presented, and the intensity of abrasion for the coastal zones of the Tsimlyansk reservoir with the most intense geoecological situation is estimated. Based on the developed software package, calculations of the processes of coastal erosion and changes in the bottom relief were performed, taking into account the spatial and temporal variability of relief formation. [ABSTRACT FROM AUTHOR]

Residual dosage has a significant impact on the settling characteristics of coal slurry flocs and the sedimentation efficiency of coal slurry. This study conducted sedimentation stirring experiments to measure the supernatant grayscale, floc size, settling velocity, and residual anionic polyacrylamide (APAM) under varying energy inputs. The investigation focused on the correlation between different levels of APAM residual and the settling characteristics of coal slurry flocs. The results show that having APAM residuals in the first three stages helps with sedimentation. This leads to lower residual levels, higher grayscale in the supernatant, bigger floc sizes, and better settling velocities. However, in the fourth stage, as APAM residual levels increased once more, the supernatant grayscale decreased linearly, floc breakup became severe, and settling velocities neared stagnation. In the second stage, a correlation was noticed between higher APAM residual levels and better settling properties of coal slurry flocs. By studying residual dosage and energy input, guidance on how to optimize the sedimentation efficiency of the thickener and reduce dosage can be provided. [ABSTRACT FROM AUTHOR]

The present paper addresses the effect of placing an intake, as a diversion structure, in different positions and with various angles in a 180° bend to investigate the scour depth around a circular pier in an SSIIM2 numerical model. The simulation was conducted by placing the intake at the 75°, 90°, 115°, 135°, and 150° positions with 45°, 60°, and 90° angles. The results indicated that the greatest effect was associated with the installation of the intake with a 90° angle at the 135° position, which decreased the maximum scour depth by a considerable amount, about 70%, compared with the bend without an intake. However, the maximum scour depth occurred with the installation of the intake at the 150° position with an intake angle of 45° and increased by 20% compared to the bend without an intake. Furthermore, the maximum and minimum scour hole wall slopes around the pier in the case of the bend with an intake respectively increased by 6.24 times and decreased by 5.1 times compared to the bend without an intake at the upstream pier. The maximum sedimentation height around the pier decreased by about 40% in the bend with an intake compared to the one without an intake. [ABSTRACT FROM AUTHOR]

The common spur dikes, which are used for river path control and bank protection, are utilized without any slots or with additional structures such as a collar or vane. The present research has been conducted to optimize the slot position in the spur dikes' body, reduce the scour depth, and improve the sedimentation conditions using the CFD model. The numerical result was compared with the Nayyer et al. 2019. A numerical and experimental investigation of the effects of combination of spur dikes in series on a flow field. Journal of the Brazilian Society of Mechanical Sciences and Engineering, 41(6), 1–11) experimental outcome. Results showed that the (LS-W-Wi, TS-W, TS-W-Wi) combination contained the slots in the web and wing of the first and third spur dike, and the slot at the web of the middle spur dike was found as the best combination of slots under clear-water conditions. This combination was conducted to reduce the scour depth by 6.8% and increase deposition by 52% compared to the spur dikes without slots, which causes reducing scour depth and an increase in the sedimentation rate of materials between two consecutive spur dikes in series. Also, the maximum scours depth decreases by up to 20%. The results revealed that the presence of slots in spur dike and their different positions have complicated and considerable influences on the form and morphology of the bed. [ABSTRACT FROM AUTHOR]

Rapid urbanization has an accelerated impact on catchment hydrology and geomorphology due to land use and land cover changes as a result of anthropogenic development activities in river catchment areas that cause increased surface runoff and higher sediment yield. The present study investigates the channel changes and sediment transport phenomena, including bed material movement from the upstream to the estuaries of the Pahang River Basin, Peninsula Malaysia. The river geometry survey associated with the spatial variation in sediment transport has confirmed that changes in river bed profile occur due to the erosion and sediment deposition along the Pahang River. The sediment size distribution for the Pahang River was very coarse sand and gravel after the December 2014 flood. The river geometry survey showed a gentle slope that can induce lower discharge typical of alluvial rivers relating to flood events. Quantitative assessment of sediment load is, therefore, of critical importance for future river basin management. [ABSTRACT FROM AUTHOR]

This is the second of a two-part New Zealand Journal of Geology and Geophysics Special Issue on understanding sedimentary systems in Aotearoa-New Zealand's Hikurangi Subduction Margin (HSM). This volume includes six research papers that explore sediment-tectonic interactions operating over a range of spatio-temporal scales. We take a distinctive perspective moving from the subduction deformation front in the Hikurangi Trough, upslope to the subduction wedge, and onshore to the Coastal Ranges. Temporally, papers span the onset of subduction in the Miocene, to disentangling provenance of turbidity currents triggered by the 2016 CE Kaikōura Earthquake. Collectively, the studies in the special issue reveal a complicated and continually evolving margin, where active tectonics and volcanism, coupled with vigorous climatic and oceanographic drivers, modulate erosion, transport, and depositional cycles of vast volumes of terrigenous sediment into ocean basins. Despite decades of significant research advances in our knowledge of the HSM, considerable scope remains for future work. A deeper understanding of fundamental tectonic-sediment interactions operating on active margins, along with the significant geohazards they pose remain outstanding research needs. Collectively, Volumes 1 and 2 highlight enduring interest in the HSM as a globally important natural laboratory for the study of subduction zone geoscience. [ABSTRACT FROM AUTHOR]

Sedimentological and rock magnetic analysis was performed on 67 turbidite samples recovered from Lithostratigraphic units I–III at IODP Site U1520 with the aim to characterise the sedimentary processes and post-depositional diagenesis within a Quaternary sequence in the Hikurangi Trough, New Zealand. Lithostratigraphic Unit I was rapidly emplaced with frequent turbidite deposition with high sedimentation rate (∼1.9 m/kyr). In contrast, in units II–III, the turbidites were finer grained and more thinly bedded, and were deposited at less than half the deposition rate of Unit I. The turbidites were classified into three clusters based on the magnetic properties. Clusters 1 and 2 are characterised by a high coercivity and SIRM/χ, but low to moderate Bcr/Bc. The recognition of gyroremanent magnetisation acquisition in their clusters indicates the diagenetic sulfidization. Cluster 3 was represented by low coercivity and SIRM/χ, but high Bcr/Bc, indicating lack of sulfidization. Restricted occurrence of Cluster 3 in Unit I may be ascribed to the high sedimentation rate, which prevents sulfidization at the sulfate–methane transition zone. Degree of sulfidization might be related with sedimentary features of turbidites in the trough, such as grain size, bed thickness and depositional rate. [ABSTRACT FROM AUTHOR]

The Albian–Aptian Goru Formation represents a fluvio-deltaic reservoir in both the Central and Southern Indus Basin, Pakistan. Using high-resolution core data, this study provides comprehensive insights into the depositional environment and its role in influencing reservoir heterogeneities in the studied formation. The sedimentological investigations demonstrate five lithofacies, namely, (i) massive sandstone (Sm), (ii) horizontal to low-angle planar laminated sandstone (Sl), (iii) planar cross-laminated sandstone (Sc), (iv) heterolithic beds (Hw and Hr), and (v) massive mudstone (Mm). Facies associations reflect shallow marine depositional settings varying from deltaic in the NE to strand plain in the SW. The framework grains of the established lithofacies exhibit quartzo-feldspathic petrofabrics, which have been sourced from stable craton-continental block settings. The petrophysical data in the core depth zone show high shale content in Well-A and lower parts of Well-B. In Well-A, the crossover between the density and neutron logs is not observed, which suggests unsaturated sands, while Well-B exhibits a permeable zone as indicated by neutron-density crossover, low gamma ray values, and relatively high porosity. The petrographic analysis and scanning electron microscopy indicate high effective porosities contributed by both primary (intergranular and intercrystalline) and secondary porosity (owing to fracturing and dissolution). The upper part of Well-B shows high porosity values up to 28% due to highly fractured quartz. Porosity values are low in the lower parts of the Well-A and Well-B due to intensive calcite cementation, chlorite recrystallization, proto matrix as well as pseudo matrix. This suggests that both Well-A and Well-B have a common source but the reservoir properties can be attributed to the depositional and post-depositional variations in the petrofabric of the studied lithological units. The Cretaceous Goru Formation in Southern Indus Basin, the Pariwar formations in Jaisalmar Basin, and Bhuj Formation in Kutch Basin share same geological history and sedimentary processes. Thus, these studies can be utilized in the exploration of Cretaceous reservoirs in these basins. [ABSTRACT FROM AUTHOR]

Investigating the geochemical composition of bulk sediments stands as a crucial method for unraveling the complexities of various sedimentary processes. However, the intricacies arising from extensive datasets and alterations in sediment due to diverse factors often impede the clear identification of underlying patterns in geochemical fluctuations. In addressing these, employing multivariate statistical analyses has proven to be an invaluable tool for elucidating intricate patterns within large dataset. In this study, we focus on the utilization of Principal Component Analysis (PCA), a multivariate statistical technique, to uncover the underlying sedimentary processes influencing distinct geochemical dataset. Specifically, our attention is directed towards the examination of geochemical data from the previously published geochemical data of metasediments from Shimla and Chail group (referred to as SCM) and the mudflat sediments of Diu Island (referred to as DMS). Our PCA outcomes reveal that the initial three principal components (PC1, PC2, and PC3) account for 52.51% and 79.30% of the total variance within the SCM and DMS geochemical data, respectively. Notably, the negative loading of SiO2, alongside positive loadings of incompatible elements and those associated with mafic rocks on PC1 within the SCM dataset, indicates sediment origins ranging from felsic to intermediate sources. Additionally, the coexistence of Th, U, Zr, and Sc, exhibiting positive loadings in PC1 and PC2, suggests a significant influence of reworking and recycling from felsic to intermediate sources. In the context of the DMS dataset, PCA analysis highlights the dominant influence of in-situ productivity and mafic sediment sources along the positive axis of PC1. Conversely, the negative axis of PC1 is shaped by intermediate and potentially other sources. Further granularity in interpretation reveals the positive axis of PC2 being attributed to weathering proxies, while the dominance of plagioclase minerals in the clayey fraction controls the positive axis of PC3. Through this investigation, our study underscores the essential role of PCA-assisted geochemical data analysis in unraveling the intricate web of processes contributing to the variance observed within sedimentary systems. By effectively distilling the multifaceted factors driving geochemical variability, this approach emerges as a pivotal asset in enhancing our understanding of sedimentary dynamics. [ABSTRACT FROM AUTHOR]

The article questions the paradigmatic nature ascribed to "the zone"—and the concomitant dismissal of the camp's—by some analyses of the politics of capital's operations, and problematizes the very notion of the paradigm. Elaborating on previous reflections concerning contemporary agro-industrial zones in Italy, the article rethinks camps against state-centric and exceptionalist readings that consider them purely as sites of exclusion. At the same time, it retains a stress on the symbolic dimension of forms of containment and extraction, going beyond a narrow political-economic approach. The zone and the camp, it is argued, are mutually imbricated "infrastructure spaces" of present-day agro-capital's operations, which, however, result from the sedimentation of spatialized techniques for labor disciplining, reproduction, and containment that have developed alongside capitalist forms of agriculture throughout the contemporary period. The camp is thus defined as a function of the political, sovereign dimensions of extraction, that may operate within but also beyond the state. Furthermore, it is underlain by differential attributions of humanness, and therefore by a specific biopolitical anthropology. Engaging in a genealogy of the (humanitarian and/as labor) camps that today proliferate in agro-industrial zones, I argue that to understand the spatial formations emerging from and sustaining the politics of contemporary capital operations a recursive analytics is necessary, that thus questions the purchase of paradigms on the grounds of their atemporality and complicates the positing of mere historical continuities. [ABSTRACT FROM AUTHOR]

This study illustrates the deposition of thermo responsive p(N-isopropyl acrylamidehydroxypropyl methacrylate) p(NIPAAm-HPMA) copolymer thin films by initiated chemical vapor deposition (iCVD) method using tert-butyl peroxide (TBPO) as the initiator. Copolymers were deposited at three different HPMA flow rates and the effects of NIPAAm/HPMA flow rate ratio on the deposition rate, structure and responsive properties of the as-deposited films were investigated. The highest deposition rate of 50 nm/min was observed for the copolymer deposited using lowest NIPAAm/HPMA monomer ratio studied. The deposition rate showed a significant increase with decreasing NIPAAm/HPMA flow ratio. Results of FTIR and XPS spectroscopy analyses revealed a significant preservation of structural retention in iCVD p(NIPAAm-HPMA) thermo-responsive films. Lower critical solution temperatures (LCST) of p(NIPAAm-HPMA) films were determined by carrying out a temperature-dependent contact angle analysis. Accordingly, it was shown that LCST was varied between 19 and 23 oC, which was observed to be dependent on the NIPAAm/HPMA monomer ratio. That LCST range is considerably below the literature-reported values for pNIPAAM, which makes the as-deposited copolymer suitable for applications that require thermos-responsive properties at lower temperatures. [ABSTRACT FROM AUTHOR]

This paper focuses on the numerical study of spherical particle sedimentation, taking into account hydrodynamic interactions. Infinite impulse response (IIR) digital filters, specially tailored to solve the sedimentation dynamics, were used in the present study to numerically solve the coupled ordinary differential equations with the time-dependent coefficients of the problem. Hydrodynamic interactions are modeled using the Rotne–Prager–Yamakawa (RPY) approximation, to which a correction is made to better account for short-range interactions. In order to validate both the proposed numerical resolution method and the RPY correction, this paper begins with the study of two interacting spherical particle sedimentation methods. Comparisons with previously published analytical or numerical results confirm the relevance of the present approach. [ABSTRACT FROM AUTHOR]

This present investigation delves into the intricate 210Pb and 137Cs radionuclides dating to govern the study of sedimentation rate, age modeling, and lifespan of the Perumal lake in the Cuddalore district, Tamil Nadu. In the study area, the 01 core sediment was excavated at the length of 51 cm, and concern for the 210Pb and 137Cs radionuclides dating using an Alpha spectrometer 7200-04 and a Gamma-ray spectrometer GC-3520 instruments. From the robust outcome, the bathymetry survey investigates the bottom topography, with a mean depth of 3.1 m and a maximum length of 11.54 km. Subsequently, the mean value of bulk density, porosity, and water content in the vertical profile of the sediment esteems as 1.52 g/cm3, 32.47 g/cm3, and 1.61%, and sediment textures unveils predominately consists of clay composition and attributes with higher content of 210Pb radionuclide in the sediments to affirms the rate and accumulation of the sediments in the aquatic environment. From the Constant Rate Supply (CRS) method, the 210Pb radionuclide activity shows the mean accumulation rate (kg/m2/year) and sedimentation rate (cm/year) indicates 0.57 ± 0.05 (kg/m2/year) and 0.84 ± 0.07 (cm/year) dated since 1944AD to 2023AD. The mean sedimentation rate of 137Cs radionuclides activity for 1963AD and 1986AD implies 0.57 ± 0.04 (cm/year) and 0.43 ± 0.03 (cm/year). From the computation, the lifespan of the lake is 369.05 years and 543.86 years with respect to 210Pb and 137Cs activities, respectively. The sedimentation rate is crucial in diminishing the lake from the future accumulation of water and sediments in the aquatic environments. [ABSTRACT FROM AUTHOR]

Flocculation sedimentation state observation could be used to facilitate interaction visualization in laboratories and establish theories for industrial manufacture. Herein, kaolinite was obtained from different sources and labeled as K1 and K2. Those characteristic characterizations indicated that silica sand was difficult to remove from refined commercial kaolinite with different sources. Some biosafe and removable surfactants have been used to evaluate the flocculation sedimentation state of kaolinite-surfactant slurry for a long time, indicating those surfactants could accelerate the settling velocities within a certain range, which could be attributed to sufficient surfactant-kaolinite interactions, but decelerate the settling velocities with the excess surfactant addition, which could be attributed to the surfactant-water colloidal characteristic. Then, the flocculation sedimentation mechanism was illustrated in detail based on the kaolinite-surfactants interaction, indicating that the excellent flocculation sedimentation state was beneficial to silica removal with sedimentation method, but the difficult flocculation sedimentation state was beneficial to size classification with differential centrifugation. [ABSTRACT FROM AUTHOR]

Soil erosion and sediment yield is a global problem that increasingly contributes to soil degradation. Although erosion analysis requires the availability of erosion and sedimentation data, the lack of sediment monitoring stations and the resulting limitations in collecting sediment measurements have necessitated the use of experimental models in many areas. The present study aimed to compare Factorial Scoring Model (FSM) and Modified Pacific South-West Inter-Agency Committee (MPSIAC) model for estimating erosion in the Mazdaran Basin (Firoozkuh, Iran). For this purpose, the required maps were prepared for both models, and the sediment rate was estimated using the two models to compare their efficiency using the corresponding maximum error (ME) and coefficient of determination (R2) values. The results showed that considering sediment based on the FSM model, the studied catchment consisted of regions with a high and very high sediment yield, while the MPSIAC model identified regions with low, medium, and high sediment yield. With an R2 value of 0.62 and an ME value of 2.24, the MPSIAC model provided more accurate estimates of the sediment yield in the studied area. Using the MPSIAC model, sediment yield was 6687.86 tons per year or the equivalent of 2.64 tons/ha per year. [ABSTRACT FROM AUTHOR]

Submarine conduits are features responsible for transporting clastic debris from continents to the deep ocean. While the architecture of conduits has been extensively studied, the process of their inception remains unclear. This study highlights the possibility that some conduits are initiated by depositional processes involving turbidity currents. Here, we present the results of eight experiments where gravity currents were allowed to develop their own pathways. The simulation tank represented natural scales of continental shelves, slopes, and basins. The initial experiments involved sediment-laden flows with low density (1–10% in volume). In first experiment runs (Series I), sediment deposition occurred primarily on the shelf and slope, resulting in an asymmetric transverse profile. This asymmetry facilitated subsequent conservative currents (1034 to 1070 kg/m3 due to salt dissolution) flowing alongside during the second series, resulting in the formation of a constructive submarine conduit. This feature is analogous to gully formations observed in various locations. This study correlates these findings with gully-like features and proposes a model where non-confined density flows can evolve into confined flows through the construction of asymmetric topography. An evolutionary model is proposed to explain the mechanism, which potentially elucidates the formation of many submarine conduits. [ABSTRACT FROM AUTHOR]

Hydraulic fracturing is the primary method used for oilfield stimulation, and the migration and settlement pattern of proppant plays a crucial role in the formation of high conductivity propping fractures in the reservoir. This study summarizes two growth modes of sand dune: the ‘overall longitudinal growth’ mode and the ‘push growth along fracture length direction’ mode. To investigate these modes, a two-phase velocity test is conducted using PIV, and the exposure difference is utilized to separate the tracer and track the single-phase velocity. By analyzing the slickwater flow field and proppant velocity field, the micro-motion mechanism behind the two dune growth modes is quantitatively examined. The results indicate that mode 1 growth of the sand dune occurs when a pump with a large mesh number, high polymer viscosity, and large displacement is used. On the other hand, mode 2 growth is observed when a pump with a small mesh number, low polymer viscosity, and small displacement is employed. It is important to note that there is no clear boundary for the migration and sedimentation mode of proppant, as they can transition into each other under certain conditions. These modes only exist during specific stages of sand dune growth. In the case of the ‘backflow’ pattern, the settlement of proppant is primarily influenced by the vortex structure of slickwater. Conversely, in the ‘direct’ pattern, the proppant is propelled forward by the drag of the fluid and settles due to its own gravity. Once the proppant placement reaches equilibrium, the direction of proppant velocity follows a normal distribution within 0°. This approach establishes a connection between the overall placement of the sand dune and the microscopic movement of the proppant and slickwater. Optimizing construction parameters during fracturing construction can enhance the effectiveness of distal proppant placement in fractures. [ABSTRACT FROM AUTHOR]

This paper presents the construction of a numerical three-dimensional model of the area of the Żelazny Most Mining Waste Storage Facility (MWSF). In the study area, the difficult geological conditions associated with glaciotectonics are accompanied by a complex hydrotechnical system of sediment deposition and sedimentary water drainage. In order to effectively reflect the water flow paths, a detailed schematization was carried out, using 700,000 boreholes and more than 300 hydrogeological cross-sections. In addition, numerous drainage sections, streams, and ditches were included to reliably assess the amount of saline water entering the underlying aquifers. This research was supported by magnetic resonance sounding (MRS) studies of the reservoir's sediments. The MWSF is currently being expanded, so the work primarily focuses on illustrating changes in the hydrodynamic field resulting from the inclusion of the new southern section. Models of similar facilities have been implemented before, but in the current one, the combination of meticulous analysis of the hydro-structural system, the water balance, a significant amount of data, the size of the facility, and the use of an unstructured discretization grid in the calculations is undoubtedly innovative and will be an important contribution to the development of analogous solutions around the world. [ABSTRACT FROM AUTHOR]

Sediment deposition is critical in maintaining riparian plant communities by providing essential nutrients and posing growth challenges. This study focuses on Cynodon dactylon, a dominant clonal species in the riparian zones of the Three Gorges Reservoir, and its interaction with sediment deposition over three years. Results indicated an average sediment deposition depth of 2.85 cm in the lower riparian regions. Observations revealed that C. dactylon coverage increased progressively at lower elevations despite its dominance diminishing with rising elevation levels. Additionally, positive linear correlations between C. dactylon coverage and sediment deposition depths were identified during flood periods, underscoring the species' role in enhancing sediment deposition. These findings suggest that C. dactylon plays a significant role in sediment accumulation, which may bolster its growth and survival prospects during subsequent growing cycles. The study highlights the importance of riparian vegetation, mainly perennial clonal species like C. dactylon, in promoting sediment accumulation and contributing to the stability and functionality of riparian ecosystems. [ABSTRACT FROM AUTHOR]

To maintain a reasonable sediment regulation system in the Loess Plateau, it is critical to determine the effects of check dam construction on sediment production and topographic changes. An indoor simulation experiment was conducted to investigate sediment production at the outlet section of the gully and micro‐topographic changes within the channel before and after dam construction. The results showed that check dam significantly affected the run‐off and sediment transport processes in the watershed. Specifically, the cross‐sectional morphology index (η) and the width‐depth ratio increased by 10.23% and 40.44%, respectively, while sediment content and particle size decreased by 39.29% and 18.58%, respectively. Additionally, the relative importance of section parameters and micro‐topographic parameters that affect sediment production rate and particle size was ranked using the random forest algorithm. The roughness after check dam construction was identified as a relatively important topographic factor affecting sediment production and particle selection by erosion. These findings provide valuable information for future check dam construction and development in the Loess Plateau region. [ABSTRACT FROM AUTHOR]

Study Design: Retrospective Upright MRI Study. Objectives: Determine the relationship between lumbar disc herniation and presence of the nerve root sedimentation sign on upright kinematic MRI patients. Methods: T2-weighted axial upright kMRI images of 100 patients with the presence of disc herniation in at least 1 lumbar disc between L1/L2 and L5/S1 were obtained. Sedimentation sign, spinal canal anterior-posterior (AP) diameter, disc height, disc herniation size, type of herniation, and zone of herniation were evaluated. A positive sedimentation sign was defined as having either the majority of nerve roots running ventrally or centrally in the canal or conglomeration of the nerve roots at the mid-disc level. Herniation types were defined as either no herniation, disc bulge, protrusion, extrusion, or sequestration. Zones of herniation were categorized as either central, lateral, or far lateral. Results: The kappa value of intra-observer reliability was.915. The kappa value of disc levels with a negative sedimentation sign were seen more frequently (n = 326, 65.2%) than those with a positive sedimentation sign (n = 174, 34.8%). The spinal canal AP diameter was significantly decreased at the L3/L4 and L4/L5 level in patients with a positive sedimentation sign. Discs with a positive sedimentation sign had a larger average size of disc herniation compared to those with a negative sign at all levels. A relationship between positivity of the sedimentation sign and disc herniation type was significant at L2/L3, L3/L4, and L4/L5. Conclusions: Patients with a positive sedimentation sign were seen to have larger disc herniations and more severely degenerated discs. [ABSTRACT FROM AUTHOR]