Effects Of Erosion Research Articles

Effects of rainfall intensity and slope gradient on soil sealing and crusting, erosion, and phosphorus solubilizing bacteria

Soil erosion significantly affects various soil properties and processes, yet its impacts on soil microbial populations remains unclear. Understanding the effects of soil erosion on soil microbial properties enables the formulation of recommendations to protect soils and reduce their vulnerability. This study aimed to determine the effects of rainfall intensity and slope on soil crusting, erosion and bacterial communities in soils with various texture and mineralogy. Three kaolinitic soils with low to medium clay content (K1, K2, and K3) and three smectitic soils with high clay content (S1, S2, and S3) were subjected to simulated rainfall at three intensities (45, 70 and 100 mm/h) and two slopes (5° and 8°). Infiltration rate was measured using a graduated cylinder in 2-minute rotations of the simulator. Runoff and sediment yield were collected in a beaker. Crust strength was measured using a cone penetrometer, and its thickness was determined with a vernier caliper. Bacterial isolates were obtained by plating serial dilutions in nutrient agar and incubating them at 25°C for 24–48 h48 hous. The phosphate solubilising bacteria were then identified. The smectitic soils formed the strongest crusts with S2 exhibiting significantly (p < 0.05) higher crust strength (18.54 Kpa) at an intensity of 45 mm/h and slope of 8° On the other hand, soil K3 (kaolinitic) had the lowest crust strength (5.4 Kpa) at an intensity of 100 mm/h and slope of 8° Soil loss increased with higher rainfall intensity and steeper slopes for the kaolinitic soils with K1 being most erodible (468.2 kg/ha) at an intensity of 100 mm/h and slope of 8° The number of phosphate solubilising bacteria decreased with increasing rainfall intensity. Furthermore, this study revealed that soil properties played a more significant role in shaping bacterial composition and phosphate solubilisation than rainfall intensity alone. These findings highlight the complex interactions between soil erosion, bacterial communities, and soil properties, which are crucial for devising effective soil conservation strategies.

Effect of Leading-Edge Erosion on the Performance of Transonic Compressor Blades

In this paper, an experimental and numerical investigation of the effect of leading-edge erosion in transonic blades was performed. The measurements were carried out on a linear blade cascade in the Transonic Cascade Wind Tunnel of DLR in Cologne at two operating points with an inflow Mach number of 1.05 and 1.12. The numerical simulations were performed by ANSYS Germany. The type and specifications of the erosion for the study were derived from real engine blades and applied to the leading edges of the experimental cascade blades using a waterjet process, as well as modeled in detail and meshed within the numerical setup. Numerical simulations and extensive wake measurements were carried out on the cascades to evaluate the aerodynamic performance. The increase in losses was quantified to be 4 percent, and a reduction in deflection and a rise in pressure were detected at both operating points.

Sea level rise estimation and projection from long-term multi-mission satellite altimetry and tidal data in the Southeast Asia region

ABSTRACT The Southeast Asian (SEA) region represents a complex coastal geographical location. Most countries in SEA are encircled by the ocean, with lowlands coastal areas. The advantages of long-term satellite altimetry and tide gauge measurements have enabled climate-related research, particularly sea level rise, to be examined extensively in spatial and temporal scales. In this study, sea level anomaly (SLA) derived from 26 years of multi-mission satellite altimeter data plus approximately 28 years of tidal data have been utilized. Then, the projection for every 10 years starting from 2030 until 2100 has been analysed using machine learning regression. The projections are then evaluated based on the global model of the Intergovernmental Panel on Climate Change (IPCC). The findings presented that sea level rise trends around SEA with overall means of 4.70 ± 0.37 mm yr−1 for the satellite altimeter and 3.41 ± 0.24 mm yr−1 for the coastal tide gauge. Sea level projection from coastal tide gauge and satellite altimeter are expected to rise up to 34.87 and 33.71 cm, respectively, in 2100. These outcomes prove that the altimetry data from Radar Altimeter Database System (RADS) and the redundant tidal data are capable in measuring the sea level in SEA. These results are also expected to be valuable for multidisciplinary environmental studies in SEA, such as coastal flooding, coastal erosion, and other effect of global warming. Thus, it would make a meaningful contribution towards Sustainable Development Goal (SDG) 13, climate action, by providing the sea level rate and prediction information.

Failure analysis of the end surface of the burner nozzle made of UMCo50 material in long-term high temperature oxygen-enriched sulfur-chlorine environment

As the core device of coal water slurry gasification technology, the failure of the burner nozzle will bring serious technical and safety problems. The purpose of this paper is to determine the mechanism of burner failure based on the characteristics of corrosion products and cracks. The results showed that the Cr2O3 oxide film on the surface of UMCo50 was damaged under the effect of mechanical erosion, high temperature and stress, and the corrosive elements S and Cl in the combustion chamber made it further cracked and peeled off. Therefore, the matrix was corroded and cracks occurred. During the crack propagation process, more M23C6 carbides were precipitated at the grain boundary, it caused Cr-depleted at the grain boundary, which reduced the corrosion resistance of the matrix near the grain boundary. The exfoliation of carbides distributed along the grain boundary also accelerated crack propagation. Through XPS and XRD analysis, it was found that the main corrosion products on the crack surface of the failed parts were: Cr2O3, CoCr2O4, CoO, Fe2O3, FeS. According to the causes of failure analysis, the corresponding improvement measures are put forward.

Submerged pulsating water jet erosion of ductile material

This article deals with the manifestations of erosion of statically acting concentrated multiple droplet impingements on materials over different lengths of time in order to assess the erosion evolution when the materials are submerged, as compared with the action of droplets on the materials under atmospheric conditions. The study aims to determine the extent of the erosive effects of droplets in underwater conditions. Experiments were conducted in a plastic pool in which the water level was varied from h = 80 to h = 120 mm to identify the effect of hydrostatic pressure at p120 = 0.1025 MPa and p80 = 0.1021 MPa. The results were compared with that of a control group of samples obtained under atmospheric air conditions. To observe the erosive damage evolution, 15 (n = 5) sites on the ductile materials EN AW-Al 99.5 and CW004A were exposed to high-intensity droplet impingement at defined exposure times. The exposure time varied from 0.125 s to 1.875 s, with increments of 0.125 s. As a droplet generator, an ultrasonic pulsating water jet with a frequency f = 20 kHz, a pressure p = 30 MPa and a nozzle diameter d = 0.4 mm was used to achieve the theoretical subsonic speed of the droplets. The results exceeded the assumptions regarding the possible attenuation of water pulses. It was found that under the theoretical speed of the jet vw = 225 m/s, the submerged condition causes attenuation in its erosive action. The incident area in the case of submerged treatment was more symmetrical. The erosion shift in term of prolonging incubation erosion stage was found to be a result of the increasing hydrostatic pressure. The results suggest that this method can also be used under submerged conditions for treatment or material drilling.

Çocuklarda Yaygın Kullanılan Şurup Formundaki İlaçların Karyojenik ve Eroziv Potansiyellerinin Değerlendirilmesi

Introduction and Aim: This study aims to evaluate the cariogenic and erosive effects of pediatric liquid medicines (PLM) on the enamel of primary teeth, which have been increasingly used in children with acute or chronic diseases. Materials and Methods: Five long-term and widely used pediatric drugs (Augmentin, Zimaks, Calpol, Vitabiol, and Ferro Sanol B) were selected for this study. In order to evaluate the erosive and cariogenic potentials of the drugs, the sucrose concentrations, pH values and calcium concentrations they dissolve from the enamel tissue were determined. The samples were subjected to acid incineration with MARS XPress (CEM Brand) Microwave oven. Calcium concentrations were then measured by Inductively Coupled Plasma-Mass Spectroscopy (ICP MS). Results: Most of the pediatric liquid drugs (80%) have a pH of less than 5.5. It is therefore critical for enamel to be affected. The syrup with the highest acidity value was Ferro sanol B (average pH 2.96 ± 0.01) and the lowest acidity value was Calpol (average pH 6.42 ± 0.03). All of the pediatric syrup samples we used in our study contain sucrose. Conclusion: As a result, it has been observed that syrups used for various reasons in early childhood may cause erosion on tooth surfaces at different pH and acidity values. All syrups examined have cariogenic effects as they contain sucrose. Calcium transition from enamel to all solutions was observed in all three time intervals for all pediatric liquid drugs. In general, the amount of dissolution increased as the holding time increased. The lowest calcium dissolution rate was observed in the Augmentin syrup sample at the first minute (15.87 mg/L), the highest calcium dissolution rate was observed in the Zimaks syrup sample (609.69 mg/L) at the eighth hour. There is no statistical correlation between the pH values of the syrups and the amount of calcium dissolved from the enamel.) Keywords: Pediatric syrup drugs, ICP-MS, Ph meter

Microwave-assisted catalytic pyrolysis with char-supported Fe-Mn catalysts: A new method for utilizing furfural residue

The primary objective of this study was to investigate the effects of bimetallic-modified biochar catalysts on the products obtained from microwave-assisted catalytic pyrolysis (MACP) of furfural residue (FR). Bimetallic modified biochar catalysts were prepared by the impregnation method with FeCl3 and MnCl2. The results showed that iron (Fe) had a greater erosion effect on the pore structure of the catalyst. Moreover, the presence of bimetals increased the contents of H2 and CO2, decreased the contents of CO and CH4 in the pyrolysis gas, with Fe demonstrating significantly higher selectivity for H2 compared to Mn. The bimetallic modification additionally increased the relative content of phenols, with 2F6M (xFyM, where x and y represent the weight percentages of Fe and Mn) reaching the highest value at 62.22 % with a total loading mass of 8 wt%. Nevertheless, the catalytic effect of the catalyst was influenced by the pore structure, resulting in the lowest phenolic content for 4F4M. At a loading mass of 2 wt%, the catalytic effect of Fe modification surpassed that of Mn. Furthermore, as the Mn content increased, the catalytic effect became more pronounced, particularly when the loading mass exceeded 4 wt%. The results demonstrated that the bimetallic modification effectively enhanced the catalytic performance of the catalyst, promoting the generation of both phenols and H2.

Study on Erosion Wear of Single- and Double-Orifice Throttling Tools for Underground Coal Gasification

In underground coal gasification, as a choke regulating the formation gas lift pressure, the throttling tool can effectively reduce the production cost, the number of ground heating and insertion equipment, and gas consumption. Because in this process, the coal is transformed into composite synthetic gas through a series of technical treatments, the throttling tool is in a working environment with high temperature and pressure. In the process of transportation of combined synthetic gas, the pulverized coal parts produced by incomplete coal combination move with the gas in the throttling tool. The high temperature and high-pressure gas carrying large-diameter pressed coal parts will cause serial erosion and wear to the throttling device, resulting in failure and well-controlled safety risks. Therefore, according to the Joule–Thomson effect, this paper independently designs downhole throttling tools with single- and double-hole structures. According to actual field conditions, the erosion wear of throttling tools with different systems in high-temperature gas–solid two-phase flow was simulated and predicted, and the internal flow field characteristics of throttling means were analyzed. The difference between the wall wear distribution, wall collision position, and wall erosion effect of different structure throttling mechanisms with the change in gas velocity was investigated, which guides the practical use of the subsequent throttling tools.

Effect of Erosion on Surface Roughness and Hydromechanical Characteristics of Abrasive-Jet Machining

The article contains the fundamental results of the experimental and numerical investigations for pneumo-abrasive unit nozzles with different geometries. The research was purposed by the pressing need to develop an inexpensive and effective working nozzle design of the air-abrasive unit which can be applied for surface processing before some technological processes are performed, as well as for surface coating, descaling after thermal treatment, processing of hollow holes of the crankshafts, smoothing of the inner surfaces of the narrow channels between the impeller blades after electric discharge machining for ultrahigh-pressure combination compressors. Several designs were considered, ranging from the simplest to those with a complicated inner channel geometry. The impact of the nozzle material and challenging inner surface application on its characteristics has also been studied. The research was done using the application of modern CFD complexes for numerical modeling of the air-abrasive mixture discharge from the working nozzle of the pneumo-abrasive unit. In addition, physical experimentation was provided. The methods applied in the research allow for profound, systematic research of spraying units operating on the air-abrasive mixture within a wide range of geometrical and mode parameters. The novelty of the gained results lies in the development of the mathematical model of the pneumo-abrasive nozzle operating process, the working out of a cheaper nozzle design, getting information about air-abrasive mixture distribution along the nozzle length, giving practical recommendations for calculation and designing a working nozzle for the jet-abrasive unit.

Responses of soil microbial metabolic limitations to erosion under contrasting soil types and management practices

AbstractSoil microbial metabolism plays an important role in supporting soil services and functionalities but is usually restricted by the availability of soil nutrients. Although soil microbial metabolism limitation (SMML) has been widely addressed with regard to various driving factors, its response to erosion has not been examined but is urgently needed given the important influence of erosion on global environments. To understand how erosion affects SMML and whether erosion's effect varies with tillage practices and soil types, we conducted a simulated erosion experiment to compare eroded and noneroded plots with contrasting soil types (Mollisol vs. loess soils) and managements (conventional tillage versus no‐tillage in plots with crops versus without crops). We measured soil extracellular enzymatic activities and quantified SMML with extracellular enzymatic stoichiometry models. In both soils, the microbes were limited by carbon (C) and phosphorus (P), but not by nitrogen, and microbial C and P limitations were greater in Mollisol than loess soils. For the Mollisol, erosion significantly increased the relative C limitation, whereas the presence of crops eliminated this increase. For the loess soils, erosion enhanced the relative C limitation regardless of crop presence and tillage management. Erosion consistently increased microbial P limitation in plots with crops, with greater effects under no‐tillage (+2.9%) compared to conventional tillage (+0.7%) conditions regardless of soil type (p &lt; 0.05). In plots without crops, microbial P limitation was increased by erosion under no‐tillage (+2.1%) but was decreased under conventional tillage (−5.6%) (p &lt; 0.05). Additionally, conventional tillage exacerbated microbial C limitation but alleviated microbial P limitation. These results indicated that erosion shifted microbial C and P limitations depending on soil type, tillage practice and the presence of plants, highlighting the importance of considering all these factors when assessing soil microbial metabolic limitation at various spatial scales.

The evolution of Kariat Arekmane Coast (province of Nador-Morocco) diachronic study and evaluation of proposed solutions

The coastline of the Nador region, in particular at Kariat Arekmane, is undergoing rapid changes influenced by natural and human factors, including submersion and erosion. An analysis of the coastline in this area has been performed in order to better understand these changes. The study began with a granulometric analysis, followed by a diachronic analysis of the coastline using the DSAS method in a GIS-ARCGIS environment. The results reveal significant variations in the study area, alternating between accretion and erosion. On average, the annual erosion rate is 0.66 m/year, while the accretion rate is 0.21 m/year. The average coastal change at Kariat Arekmane is 1.102 m/year, divided into two sectors: the first, undergoing severe erosion, comprises sandy shores and cliff areas, while the second, the western beach, benefits from accretion due to protective rock structures. The main causes of these coastal changes are coastal infrastructures and hydrodynamic forces. To solve this problem, several solutions for preserving Arekmane's coastline are currently being proposed and evaluated. Appropriate coastal management is essential to protect this region and mitigate the adverse effects of coastal erosion.

Effect of chlorine salt erosion on flexural performance of GFRP and steel bars hybrid reinforced beams

Hybrid reinforced beams subjected to chloride salt erosion are susceptible to chloride ion infiltration, leading to corrosion of longitudinal reinforcement within the beams and thus impacting their flexural capacity. This study aims to assess the impact of varying reinforcement material area ratio and chloride salt erosion environments on the flexural behavior of hybrid GFRP-steel reinforced concrete beams. This is achieved through bending tests conducted on one reinforced concrete beam and seven concrete beams incorporating hybrid GFRP-steel reinforcement, coupled with finite element analysis. The results demonstrate that the better reinforcement material area ratio (RMAR) for hybrid reinforced beams is 1.36. When compared to the non-eroded beam, beams exposed to chloride salt erosion consistently exhibited a failure mode characterized by steel yield-concrete crushing failure, and the development of cross-sectional strain of the erosion beams aligning with the assumption of a plane section. The more severe erosion conditions lead to increased beam deflection, reduced maximum crack width, and reduced load-bearing capacity. Based on these findings, formula for accurately predicting the upper limits of load-induced crack widths at all levels and the formula for the load carrying capacity are deduced. Moreover, the feasibility of the nonlinear spring finite element method is validated. The results of this study offer significant reference value for the design and practical application of hybrid reinforcement beams.

First-principles study of F adsorption by TiN with its oxide surface in three-dimensional NAND flash memory

Three-dimensional (3D) NAND flash memory is a key technology in the field of mainstream memory solutions, which is primarily due to its extremely low bit cost. The architecture of 3D NAND, characterized by its vertically stacked design, substantially enhances the capacity of individual chips. This advancement is completely consistent with the demands for high-capacity data storage in contemporary environments, securing its widespread adoption in diverse application scenarios. As storage density increases, the complexity of process integration increases, bringing new challenges. The word lines in 3D NAND are typically filled by using gate replacement techniques, and compared with chemical vapor deposition (CVD), atomic layer deposition (ALD) is favored for its superior step-coverage, especially for depositing tungsten (W) at the gate. However, due to the complexity of the replacement gate deposition structure, fluorine (F) residues are found in the voids of the tungsten metal gate filling structure and diffuse into the surrounding structure under subsequent process conditions, corroding other films such as silicon oxide and degrading device performance and reliability. To alleviate the problem of fluorine attack, a thin layer of titanium nitride is usually deposited as a barrier layer before deposition of tungsten gate, which blocks the fluorine in the tungsten gate and prevents its diffusion into the oxide layer. Previously, there were studies to increase the ability to stop F diffusion by varying the thickness of the F blocking layer (TiN). However, increasing the thickness of TiN will further increase the complexity of high aspect ratio etching in the 3D NAND process, which will have adverse effect on subsequent processes. To further minimize the effect of fluorine erosion, residual fluorine elements can be removed by introducing annealing in the subsequent process flow. In the actual 3D NAND process, elemental fluorine (F) is adsorbed and accumulates on the TiN surface, and is further activated by subsequent high-temperature processes, leading to severe fluorine erosion. The delay between TiN deposition and subsequent processing steps is hypothesized to facilitate fluorine adsorption due to the oxidation of TiN. This work corroborates this hypothesis through first-principles calculations, and demonstrates the role of TiN oxidation in fluorine adsorption. In this work, we evaluate the effect of this oxidation on the fluorine-blocking effectiveness of the TiN barrier layer. We simulate the adsorption of fluorine-containing by-products on TiN and its oxides, providing theoretical insights into mitigating fluorine attack. The higher degree of oxidation of TiN is more likely to cause F adsorption, and Ti exposed surface TiN is more prone to oxidation, which is more likely to cause F adsorption in unoxidized condition and oxidized condition. Based on these insights, we implemente an ammonia purge treatment in 3D NAND manufacturing, which effectively minimizes fluorine attack, reducing the leakage probability of word line by 25% and wafer warpage by 43%.

Effects of Soil Erosion on the Tillage-Layer Quality and Limiting Factors of Sloping Farmland

Soil erosion is the key factor leading to the degradation of tillage-layer quality, which directly threatens regional food and ecological security. To study the characteristics of soil structure, water retention capacity, and nutrient changes in the tillage layer of purple soil sloping farmland under different erosion conditions, a shovel soil erosion test was performed to distinguish the factors that hinder the tillage-layer quality of sloping farmland under different erosion degrees. The degradation of soil structure showed that with the intensification of erosion, soil bulk density, soil capillary porosity, and sand content displayed an overall increasing trend; the soil water retention degradation was expressed by the average increase in the soil water holding capacity and the average decrease in the infiltration rate; soil nutrient degradation was derived from the average decrease in soil nutrient content. At the initial stage of erosion, the soil nutrient degradation was extremely sensitive to soil erosion, which was the limiting factor of the tillage layer; when the erosion reached stage E-15 (erosion 15 cm), the soil nutrients, soil permeability, and soil capillary porosity became the limiting factors; for E-20 (erosion 20 cm), the limiting factors added an index on the basis of stage E-15, namely, soil total porosity. When soil erosion continued for 53 years, the tillage-layer quality index was lower than the threshold value (0.46). Reconstructing soil profile of the tillage layer is an effective way to break the limitations of the barrier factors and improve the tillage-layer quality.

Saltwater Intrusion Into a Confined Island Aquifer Driven by Erosion, Changing Recharge, Sea‐Level Rise, and Coastal Flooding

AbstractAquifers on small islands are at risk of salinization due to low elevations and limited adaptive capacity, and present risks will be exacerbated by climate change. Most studies addressing small‐island saltwater intrusion (SWI) have focused on homogeneous sandy islands and one or two hydraulic disturbances. We herein investigate SWI dynamics in a layered, confined island aquifer in response to multiple environmental perturbations related to climate change, with two considered in tandem. Our field and modeling work is based on an island aquifer that provides the drinking water supply for an Indigenous community in Atlantic Canada. Observation well data and electrical resistivity profiles were used to calibrate a numerical model (HydroGeoSphere) of coupled groundwater flow and salt transport. The calibrated model was used to simulate the impacts of climate change including sea‐level rise (SLR), storm surge overtopping, changing aquifer recharge, and erosion. Simulated aquifer conditions were resilient to surges because the confining layer prevented deeper saltwater leaching. However, reduced recharge and erosion resulted in saltwater wedge migration of 170 and 110 m, respectively when considered individually, and up to 295 m (i.e., into the wellfield) when considered together. Despite the confining conditions, SLR resulted in wedge migration up to 55 m as the confining pressures were not sufficient to resist wedge movement. This is the first study to harness an integrated, surface‐subsurface hydrologic model to assess effects of coastal erosion and other hydroclimatic stressors on island aquifers, highlighting that climate change can drive extensive salinization of critical groundwater resources.

The impact of soil erosion on environments: A case study of the Oued Beht Watershed (Morocco)

Soil erosion poses a significant environmental challenge in the Oued Beht watershed, Morocco, impacting local ecosystems and water quality. This study investigates the causes and effects of soil erosion in this region, utilizing Geographic Information System (GIS) tools and field techniques to analyze land use changes, agricultural practices, soil properties, and precipitation patterns. The findings establish a clear link between soil degradation and declining water quality in nearby aquatic environments. Major contributors to soil erosion include intensive agriculture, climate change, deforestation, vegetation degradation, and steep terrain. To predict future erosion rates, models were used, emphasizing the need for proactive management strategies. To address these issues, the study suggests implementing sustainable agricultural practices and soil conservation measures like agroforestry, vegetative buffer strips, and slope management. These measures can effectively reduce soil erosion and its adverse effects on water quality. The study underscores the importance of integrated management approaches to preserve biodiversity and soil fertility in the region. The findings provide crucial information for policymakers to adopt sustainable land conservation and management policies, ensuring the protection of aquatic ecosystems and environmental sustainability in the Oued Beht watershed.

Geosynthetic solutions for river and coastal protection works

Riverine floods and coastal erosion are some of the most frequent natural calamities in India that affect millions of people, cause loss of lives, and damage infrastructure and agriculture. Application of geosynthetic products provides a sustainable, eco-friendly, quick &amp; economical solution among all the conventional river and coastal protection works. This paper focuses on geosynthetic solutions to the river and coastal erosion with the help of case studies. To safeguard against the frequent floods, the banks of the river Brahmaputra near Lakhimpur were strengthened while providing geosynthetic anti-erosion measures. A sandfilled geotextile mattress of 0.1m thickness was provided on the river bank slopes of the Brahmaputra River, Assam. Also, this paper reveals the successful application of specially engineered nonwoven geotextile bags with high abrasion resistance, to mitigate the effects of erosion of the banks of Churni River, West Bengal. This solution reinforces the embankment's edge and increases the factor of safety against repeated floods. The third case study discusses the coastal protection work at Kattupalli, Tamilnadu where a 620ms long shoreline was protected against progressive beach erosion. An embankment was formed using 6 numbers of 3.0m theoretical diameter and 20.0m long high-performance geotextile tubes in crosssection and a small geotextile tube was used for scour protection ahead of the structure. The embankment thus formed also provided ways for beach nourishment and land reclamation at the site.

Dating the late Miocene marine sediments around the southern middle Durance valley (Provence, SE France): new evidences for a Tortonian age

The present study aims dating the topmost 50 m of a 115 m-long core retrieved from a valley located in the Cadarache Area (Upper Provence, South East France). Based on burial dating by in situ produced cosmogenic nuclides (10Be, 26Al and 21Ne), and paleomagnetic analyses, a Tortonian age was determined for the sedimentary succession exhibited in the core. In addition, thin sections, grain size analyses and quartz morphoscopy were used to characterize a shallow marine environment and to correlate the sediment core to the surrounding exposed sections. When comparing the studied sedimentary record to global sea level estimates, we establish that the local Tortonian transgression was not synchronous with the global scale sea level high-stand, but happened more likely later, during a global regressive trend. The timing of the Tortonian flooding in Upper Provence was therefore most probably driven by regional tectonic forcing. Finally, the Tortonian shallow marine sediments are topped by lacustrine tight carbonates. These carbonates protect the marine sediments from the following major erosional events resulting from the Messinian sea level drop and from interglacial-glacial fluctuations that both yielded to the present-day valley topography.

An overview of riverbank erosion prediction techniques applied to the Mekong Delta, Vietnam

In recent times, the Mekong Delta has been experiencing severe riverbank erosion, causing significant damage to property, homes, land, and riverside infrastructure. The region is facing increasing intensity of erosion events, attributed to the impact of climate change and the effects of hydropower dams and water control systems upstream on the Mekong River. This paper discusses five key methodologies currently applied for riverbank erosion prediction in the Mekong Delta: digital map overlay, historical topographic data analysis, geophysical and terrain change analysis, physical phenomenon simulation using analogous conditions, and empirical formula-based prediction. Each method's theoretical foundation, procedural steps, and potential limitations are explored in depth.

Mitigation strategies and measures for the protection of working railway bridges from landslides and erosion phenomena: the case study of Liguria

The Italian territory is marked by complex geology, morphology and hydrography. For this reason, hydrogeological instability is a primal issue to phenomena such as landslides, flooding and associated erosion phenomena. Within this context, the protection of existing infrastructures plays a significant role along with maintaining operational continuity and promptly restoring circulation after a forced traffic interruption. In October 2020, the railway line Cuneo-Breil-Ventimiglia was interested in a series of landslides and erosion phenomena, due to a sequence of strong meteorological events. The paper presents the study, planning, design and realization of the mitigation measures. An investigation campaign, involving both the existing structures and the geological context, al-lowed to obtain a 3D reconstruction of both the bridges and the nearby slopes, as well as the characterization of materials, the identification of high-risk areas and the design of the solution to reinforce the existing slopes and mitigate the erosion effect on bridges foundations. The software Rocscience Slide has been intensively used for the geotechnical modelling of landslides as well as to design structural works such as soil nailing. Meanwhile, the hydraulic study of the river was performed to assess the hydraulic compatibility of the riverbed construction sites.