Soil Deposits Research Articles

Impacts of straw mulching in longitudinal furrows on hillslope soil erosion and deposition in the Chinese Mollisol region

In the Northeast Mollisol region of China, straw mulching has a great effect on preventing soil loss from ridge tillage, but how furrow straw mulching (FSM) impacts the spatial distribution of erosion-deposition and sediment sources in longitudinal ridge tillage systems is still unclear. Therefore, this study was to quantify the effects of the FSM on the spatial distribution of soil erosion-deposition and sediment sources in longitudinal ridge tillage systems by using the magnetism tracing methodology and indoor simulation rainfall experiments. The experimental treatments included two surface treatments: without the FSM (NFSM) and with the FSM of 0.30 kg·m−2 amount, two rainfall intensities of 50 and 100 mm h−1 were included; each experiment was run for 60 min at a soil pan with a 5° slope gradient, 6.2 m length, 1.3 m width and 0.7 m depth. The results indicated that, compared with the NFSM treatment, the total slope runoff and soil loss in the FSM treatment at two rainfall intensities were decreased by 41.6 % and 99.5 % and by 37.9 % and 97.7 %, respectively, and the reduction in slope runoff and soil loss decreased with an increase of rainfall intensity. The total mass of sediments intercepted by straw mulching on the entire slope accounted for 36.9 % and 10.4 % of the total soil loss in the NFSM treatment, respectively. Erosion regimes dominated on the hillslope of the NFSM treatment with strong-weak alternation at two rainfall intensities, while for the FSM treatment, only deposition regime was observed at 50 mm h−1 rainfall intensity; a slight change with erosion-deposition on the ridge tops was observed and deposition in the furrows was observed at 100 mm h−1 rainfall intensity. Furthermore, the FSM treatment changed the main sediment source from ridge tops to furrows on the hillslope compared to the NFSM treatment, whose sediment contributions from the ridge tops and the furrows at the two rainfall intensities were approximately 16.4 % and 83.6 %, respectively. In conclusion, FSM should be promoted due to its high efficiency in decreasing slope runoff and intercepting sediments. The findings of this study served as a scientific reference for effectively controlling soil erosion along slopes in the Chinese Mollisol region.

Seismic wave amplification in a weakly nonlinear two-layered soil deposit

Based on numerous observations, local soil site conditions can significantly affect the formation of seismic responses. In this paper, we examine seismic responses caused by shear waves propagating through a two-layered soil deposit. The aim of the research is to study the phenomenon of amplification of shear waves due to the resonant properties of the soil deposit and the nonlinear characteristics of partial layers, which are assumed to be the cubically nonlinear continuous media. The target problem relates to a nonlinear boundary value problem, the solution of which is carried out using a semi-analytical approach. According to the approach, the problem’s solution is sought using the method of separation of variables, while the solution to the corresponding spectral problem is derived in the form of a power series. Additionally, good agreement is shown between theoretical studies and numerical simulations. The developed approach allows one to evaluate the amplification factor for a nonlinear two-layered soil deposit and to detect changes in the shape of amplification factor profiles when the frequency of an incident wave on a rigid bedrock is varied.

Periodic foundation piles for the seismic protection of structures

This study introduces a novel solution for seismic protection of structures based on resonant metamaterials, named Periodic Foundation Piles, which can be integrated with deformable soil deposits in order to filter shear waves in a specific frequency range. A Periodic Foundation Pile consists of an array of vertical periodic structural elements containing internal resonators suitably tuned to one or more natural frequencies of the soil deposit. The proposed system is equivalent to a discontinuous foundation pile and can be installed in the ground with approximately the same procedure for piles, thus making it suitable also for applications in existing structures. The performance of the Periodic Foundation Piles in reducing the amplitude of a seismic motion has been shown through non-linear site response analyses carried out using real acceleration records as input motion. A soil deposit with an increasing shear wave velocity profile has been considered; the nonlinear behaviour of the soil has been modelled through the Iwan model, calibrated using a normalized secant shear modulus curve accounting for the influence of the confining pressure on the stress-strain relationship. Numerical results, presented in terms of peak acceleration, horizontal displacement and shear deformation profiles, as well as in terms of Fourier amplitude and response spectra, indicate that Periodic Foundation Piles may noticeably reduce the amplitudes of seismic motion in a suitable frequency range, hence potentially representing an innovative strategy to mitigate the effects of earthquakes on structures.

Effects of naturally sourced bitumen samples from Alberta oil sands region (Canada) on aquatic benthic invertebrates: A case study with Chironomus riparius

Athabasca oil sands in Alberta, Canada, are large bitumen deposits and are one of the world's largest petroleum reserves. This research contributes to the growing body of knowledge on the influence of this naturally occurring bitumen on freshwaters. Using laboratory-based exposure studies, we examined the life cycle responses of the aquatic midge Chironomus riparius to both naturally formed solid bitumen incorporated in the sediment and its corresponding aqueous extracts, denominated as elutriates. The 28-day partial life cycle assay involved bitumen samples from two distinct geological origins in the Athabasca River Basin (Clearwater and McMurray formations), comprising both weathered and freshly collected bitumen from a total of 4 different rivers. Our results demonstrate a measurable impact of sediment-embedded bitumen on C. riparius life history traits, namely on their growth and emergence patterns. Furthermore, we observed that bitumen samples from the Ells River (McMurray formation), which were freshly collected from exposed river bank soil deposits, exerted the strongest effects on most studied eco-physiological endpoints. Bitumen extracts from the Steepbank River and Athabasca River in the McMurray Formation and Steepbank River in the Clearwater Formation followed, underscoring the geographical variance in bitumen-induced toxicity. Exposure to elutriates, simulating “weathered” bitumen generally did not induce adverse effects in C. riparius life-cycle endpoints compared to elutriates prepared from freshly eroded bank soils. This emphasizes the importance of considering bitumen sources, their age, and the aquatic receiving environment when assessing potential adverse exposure effects. Our study shows that exposure to freshly eroded soils/sediments can potentially affect benthic invertebrates. More research is needed to understand how hydrological changes affect bitumen sediment exposure and the associated risks to aquatic biota.

Dry Deciduous Forests of the Poona District, Deccan, India

The deciduous vegetation grows in various ghats and hills in the Poona district. The present note describes the type from the Katraj ghats, on the south of Poona at a distance of 6 miles.The area consists of flat plateau at the top, eastern and western slopes and narrow valleys through which small rivulets flow during monsoons. The mountains are formed of trap rock, the strata of which dip towards east. Thus the eastern slopes are gentle with better developed soil but the western escarpments are steep comparatively dry with shallow soil. Seepage water is seen on eastern slope during monsoon. Alluvial soil deposits in the valley. The average rainfall is about 27".The following vegetation types are described:(I) Top of the plateau: They are mainly covered with Boswellia serrata which is regenerating profusely where biotic interference is excluded and the soil is dry shallow and gravelly.(II) The western slopes: These slopes bear a low type of forest. The following trees are common-Boswellia serrata, Lannea coromandelica, Diospyros montana and Largerstroemia parviflora. Shrubs-Acacia sp., Lantana camara, Zizyphus xylopyrus, Rhus mysorensis, Flacourtia, Cipadessa baccifera, Gymnosporia spinosa and Securinega sp.Herbs-Tridax procumbens, Leucas sp., Cocculus sp., Polyzygus tuberosus, Sida sp., Arisaema sp., Desmodium sp., Acanthospermum hispidum, Celosia sp. etc.This vegetation is also affected adversely by the biotic interference since lopping, coppicing and grazing are prevalent.(III) Eastern slope (top portion) ; It bears a community of Boswellia serrata-Diospyros montana-Lannea coromandelica on dry shallow and rocky soil. The commonest shrubs are Acacia sp., Zizyphus xylopyrus, Lantana camara, Cryptolepis buchanani, Woodfordia fruticosa, Cissuspallida and Securinega sp.The common herbaceous vegetation consists ot Locculus sp., Leucas sp., Tridax procumbens, Curculigo sp., Polyzygus tuberosus, etc.(IV) Eastern slope (lower portion): It bears a community of Tectona grandis-Lannea coromandelica-Diospyros-Boswellia serrata.Teak and Lannea coromandelica are predominant on the alluvial deposits towards the valley and higher up. Diospyros sp. and Boswellia become prominent in dry trap soil. Diospyros on alluvial soils is heavily infected by Viscum. But incidence of the parasite decreases in trees which are growing on dry trap rocks elsewhere in the area. Commonest shrubs in the community are Acacia sp., Clerodendron serratum, Zizyphus xylopyrus, Cissus pallida and Lantana camara. Commonest herbs are Leucas sp., Tridax procumbens, Hemidesmus indicus, Curcuma montana, Cocculus sp., Polyzygus tuberosus, Trichodesma sp., Crotalaria sp., Indigofera sp., Celosia sp., Aerva javanica, etc.Various stages of succession are seen in the area and regeneration of teak, Boswellta, Lagerstroemia. Lannea is common on different types of soils.

Utilizing Chlorophyll as a Natural Chelating Agent for the Remediation of Heavy Metal Pollution: A Density Functional Theory Study

Heavy metal pollution, driven by industrialization, urbanization, and inadequate waste management, poses significant environmental and health risks. Toxic elements such as lead (Pb), mercury (Hg), cadmium (Cd), and arsenic (As) persist in ecosystems and bioaccumulate within biological systems, leading to severe health effects. Major contamination sources include industrial processes, agricultural practices, and improper waste disposal. Unlike organic pollutants, heavy metals do not degrade over time, allowing long-distance transport and deposition in soils and sediments. Traditional remediation methods often generate secondary waste, while adsorption techniques face material regeneration challenges. Natural chelating agents like chlorophyll, integral to photosynthesis, offer a promising alternative due to their ability to form stable complexes with heavy metals, reducing their bioavailability and toxicity. This study explores chlorophyll's potential in sequestering heavy metals through Density Functional Theory (DFT) to analyze the electronic structure and bonding characteristics of metal-chlorophyll complexes, aiming to develop sustainable and eco-friendly remediation strategies.

Analysis of subsidence zone of the village access road in Jatirunggo, Semarang Regency using microtremor data

The rehabilitation of the subsidence phenomenon in Jatikurung sub-village, Jatirunggo village, Pringapus Subdistrict, Semarang Regency, Central Java, has been carried out for a long time however, it has never been successful. Every time an embankment is made, it is only a matter of time before another subsidence occurs. This research aims to investigate the subsurface structure of the subsidence sites. It is proposed to be used as a reference for structural planning in the treatment of road subsidence. Subsurface information is very useful in addressing the subsidence problem more effectively and precisely. The method used was by recording microtremor data and analyzing shear wave velocity and Poisson ratio as parameters to determine the type of subsurface layer. The obtained results are in the form of clay layers to bedrock layers at a depth of 35m. The movement occurred because of the soft or loose soil below and at the edge of the road above the impermeable clay layer. In addition, to the north side of the collapse point is a fairly deep cliff, which is a burden on the bedrock. When it was raining, the soil filled with water and there was even a flow of water in the soil deposits (piping) resulting in the ground movement toward the lower part.

Исследование физико-механических свойств сгущенных хвостов обогащения и формируемого искусственного массива в выработанном пространстве карьера

The article presents the results of studying physical and mechanical properties of thickened concentration tailings, as well as regularities in their changes during the dumping process in mined-out spaces of open-pits. The necessity of experimental studies is explained by the existing discrepancy between the parameters of the artificial hydraulic deposition of soils and the design solutions, in particular, the spreading angles, the lack of a ponding zone created within the rock mass body, as well as the insignificant influence on the intakes of the dewatering plant. The following characteristics of the thickened tailings that define the parameters of the hydraulic deposition technology and the artificial massif formed inside the pit at the design stage were taken as the research objects: density, mineral density, absolute and relative moisture content, storactivity, viscosity, shear stress, flowing angle, and water conductivity. These characteristics were tested using conventional methods. Representative samples were collected at the discharge points of the thickened tailings in the open pit and directly at the discharge point of the thickener No.2 at the paste thickening plant. It was established that as the thickened tailings are transported to the place of their deposition inside the open pit, no changes take place in their density, moisture content, and water conductivity, but the rheological properties, such as viscosity, shear stress, angle of spreading undergo a significant change, which should be taken into account in design solutions. Being familiar with the technology of thickening, transportation and storage of paste mixtures in open-pit mines allows us to consider the mechanical impact on the pulp flocculi and their destruction, consisting in the rupture of the macromolecules, as the main cause of changes in the structure and properties of the thickened tailings.

Crafting resilience: persistence and adaptation of the ceramic manufacture at Roca Vecchia from the Middle to the Final Bronze Age phases

Through the second millennium BC, Bronze Age communities of Southern Italy have shown a remarkable degree of resilience in coping with changes in both macro-trends of cultural interaction and the landscape. In this paper, we will examine long-term processes of adaptation to shifting historical and environmental conditions from the vantage point of the impasto ware production at the site of Roca Vecchia (Melendugno-Lecce, IT), one of the main hubs of interaction for the Bronze Age of the Central Mediterranean. Sixty-eight ceramic individuals coming from the Middle to the Final Bronze Age levels and seven soil deposits from the site surroundings were analysed by petrography and fifteen were selected for SEM–EDX examination. We explore how changes in the complex history of the settlement and the surrounding landscape are matched in technological choices operated by the community of practice responsible for producing impasto pottery at Roca, in a moment when the long-range connection with the Aegean world was at its historical peak.

Source and Migration Pathways of Heavy Metals in Soils from an Iron Mine in Baotou City, China

The exploitation of iron ore could cause heavy metals pollution in the soils, which threatens the ecosystem and human health. In this study, soil, stream sediment, tailings, rock, and atmospheric deposition samples were collected from an iron mine in Baotou City. The concentrations of As, Cd, Cr, Cu, Hg, Ni, Pb, Zn, Al2O3, CaO, K2O, MgO, Na2O, SiO2, and Fe2O3, as well as the mineral composition and heavy metal speciation of the samples, were analyzed for pollution assessment and source identification of heavy metals. The results reveal that the concentration of Cu in the soils was significantly higher than the background value, and an unpolluted to moderately polluted state was the main pollution level. By analyzing the relationship between Cu/Al2O3 and CaO in different samples, as well as the characteristics of the chemical index of alteration (CIA), mineral composition, and the chemical speciation of Cu in soils and profiles, the results suggest that tailings were the source of Cu pollution in soils. The distribution characteristics of Cu and CaO in stream sediments indicated that hydraulic transport may be one of the main migration pathways. In addition, wind transport may also be a pathway of migration.

Recycled Excavation Soils as Sustainable Supplementary Cementitious Materials: Kaolinite Content and Performance Implications.

In response to the environmental implications of the massive quantities of excavation soil generated by global urbanization and infrastructure development, recent research efforts have explored the repurposing of calcined excavation soils as sustainable supplementary cementitious materials (SCMs). As it is still at an early stage, current research lacks systematic analysis across diverse soil deposits regarding their reactivity and mechanical properties within cementitious binders, despite recognized geographical variability in kaolinite content. Through comprehensive experimentation with soils sourced from four major southern Chinese cities, this study presents a pioneering assessment of the compressive strength, pozzolanic reactivity (X-ray diffraction, Fourier-transform infrared spectroscopy, solid-state nuclear magnetic resonance), and microstructural development (mercury intrusion porosimetry, scanning electron microscopy) of mortars modified by various calcined excavation soils (up to 28 days curing). The experimental data suggest that soils with a kaolinite content above 53.39% produce mortars of equal or superior quality to plain cement mixes, primarily due to their refined pore structures, microstructural densification, and enhanced hydration reactions. The findings highlight kaolinite-specifically, aluminum content-as the principal indicator of excavation soil viability for SCM application, suggesting a promising avenue for sustainable construction practices.

Investigating a hybrid extreme learning machine coupled with Dingo Optimization Algorithm for modeling liquefaction triggering in sand-silt mixtures

Liquefaction is a devastating consequence of earthquakes that occurs in loose, saturated soil deposits, resulting in catastrophic ground failure. Accurate prediction of such geotechnical parameter is crucial for mitigating hazards, assessing risks, and advancing geotechnical engineering. This study introduces a novel predictive model that combines Extreme Learning Machine (ELM) with Dingo Optimization Algorithm (DOA) to estimate strain energy-based liquefaction resistance. The hybrid model (ELM-DOA) is compared with the classical ELM, Adaptive Neuro-Fuzzy Inference System with Fuzzy C-Means (ANFIS-FCM model), and Sub-clustering (ANFIS-Sub model). Also, two data pre-processing scenarios are employed, namely traditional linear and non-linear normalization. The results demonstrate that non-linear normalization significantly enhances the prediction performance of all models by approximately 25% compared to linear normalization. Furthermore, the ELM-DOA model achieves the most accurate predictions, exhibiting the lowest root mean square error (484.286 J/m3), mean absolute percentage error (24.900%), mean absolute error (404.416 J/m3), and the highest correlation of determination (0.935). Additionally, a Graphical User Interface (GUI) has been developed, specifically tailored for the ELM-DOA model, to assist engineers and researchers in maximizing the utilization of this predictive model. The GUI provides a user-friendly platform for easy input of data and accessing the model's predictions, enhancing its practical applicability. Overall, the results strongly support the proposed hybrid model with GUI serving as an effective tool for assessing soil liquefaction resistance in geotechnical engineering, aiding in predicting and mitigating liquefaction hazards.

Rainstorm erosion difference and topographical changes induced by heavy rainfall between afforestation and grassland restoration catchments on the Chinese Loess Plateau

The frequency and intensity of heavy rainfall on the Chinese Loess Plateau (CLP) are increasing due to global climate change, which has caused severe soil erosion. However, precise evaluation of heavy rainfall-induced soil erosion, deposition, and related topographical changes at the catchment scale is lacking, and there is uncertainty as to how effectively trees can inhibit erosion, especially during heavy rainfall. In this study, we selected a pair of catchments with afforestation and natural grassland restoration on the CLP. Precise evaluation of erosion and topographic changes induced by heavy rainfall was conducted based on airborne light detection and ranging (LiDAR) data. In the grassland catchment, the gully bed area increased by 17.6 %, the gully slope and inter-gully land area decreased by 1.4 %, and the length of the gully shoulder line decreased by 4.4 %. Conversely, the forestland catchment experienced a decrease in gully bed area of 8.8 %, an increase in gully slope area of 5.3 %, a decrease in inter-gully land area of 9.9 %, and a decrease in the length of the gully shoulder line of 11.4 %. Following heavy rainfall, both catchments experienced a substantial increase in terrain relief. Soil erosion in the gully slope accounted for >90 % of the total erosion in both catchments, while deposition in the same area contributed to >75 % of the total deposition. The grassland catchment experienced a unit area erosion of 233,908 m3 km−2, which was 4.7 times greater than that of the forestland catchment (49,768 m3 km−2). In both catchments, erosion predominantly transpired in the steep slope region adjacent to the gully shoulder line, accounting for >15 % of the gully slope erosion area. The grassland catchment exhibited a continuous distribution pattern of erosion and deposition, whereas the forestland catchment exhibited a scattered and intertwined distribution pattern. This study is essential for further research on erosion and topographic changes induced by extreme weather events and to determine appropriate measures.

Applicability of 1D site response analysis to shallow sedimentary basins: A critical evaluation through physics‐based 3D ground motion simulations

AbstractOne‐dimensional site response analysis (1D SRA) remains the standard practice in considering the effect of local soil deposits and predicting site‐specific ground motions, although its range of applicability to realistic seismic wavefields is still in question. In this 1D approach, horizontal and vertical ground shaking are assumed to be induced by vertically propagating shear and compressional waves, respectively. A recent study based on analytical two‐dimensional (2D) plane waves and simple point source earthquake simulations has shown two mechanistic limitations in this 1D modelling technique for general inclined seismic waves, that is, systematic over‐prediction of the vertical motion and wave trapping in the 1D soil column. In this article, we evaluate in detail the applicability of this 1D modelling approach to realistic three‐dimensional (3D) simulated seismic wavefields in shallow sedimentary basins. Linear‐viscoelastic 1D SRA predictions using two types of input motions that are commonly used in practice—rock outcrop and in‐column motions, are compared with the reference true site response results from 3D earthquake simulations in terms of various measures in the frequency and time domain. It is shown that the horizontal motion in the 3D seismic wavefield exhibits dominant shear wave propagation phenomenon, while the vertical motion is a combined effect of compressional and shear waves and can be over‐predicted by the 1D approach when the incident seismic waves are inclined. Direct evidence of the wave refraction process that leads to the vertical motion over‐prediction is provided. 1D SRA with in‐column inputs can yield motions that have significantly longer duration compared to the true 3D site response solution due to trapped waves, casting in doubt the frequent need for increased soil damping in existing site studies to compensate for wave attenuation due to scattering alone. Sensitivity investigation on the increase of soil profile damping by a multiplier Dmul shows Dmul values compatible with those found in the literature for both horizontal and vertical motions. It is shown that the level of Dmul optimized for a best match of the spectral acceleration is dependent on the characteristic of the input motion and a larger Dmul is typically required for the vertical component. In contrast, 1D SRA with outcrop motions predicts motions with shorter significant duration due to its inability to capture the basin‐edge generated surface waves. A suite of ground motion simulations was performed to assess the sensitivity of the observations to the basin geologic structure including the velocity gradient, rock‐basin impedance contrast and basin depth. The analysis results show that the accuracy of the simplified 1D procedure is dependent on the wavefield composition of both the input motions and the true 3D site response solution. While the horizontal motions in shallow sedimentary basins can, to the first order, be reasonably captured by the simplified 1D approach, 1D SRA for the vertical component is in general not reliable and contributions from inclined shear waves should be accounted for in site‐specific evaluation of the vertical design ground motion.

Paleopalynological Analysis of Primulaceae Family Evolution during the New Holocene Period in Elbasan, Albania

This paper presents pioneering paleopalynological data concerning the Primulaceae family during the New Holocene period in Elbasan, Albania. Fossil pollen data were extracted from soil deposits dating back to the last 20th centuries, shedding light on the evolutionary trajectory of Primulaceae Family plants in the region. Soil samples, primarily weighing approximately 0.5 kg and retrieved from depths ranging from 4 m to the surface, were collected at five stations in the Elbasan area using a dry rotary drilling probe between October and November 2023. The study aims to unveil the evolutionary dynamics of Primulaceae plants during the New Holocene, offering novel insights into their paleoenvironmental interactions. The Holocene epoch marks a critical period characterized by significant shifts in climate and ecological conditions. Understanding plant evolution during this era provides valuable insights into environmental dynamics and human impact on vegetation. A total of 485 Primulaceae palynomorphs were identified across all analysed soil samples, indicating consistent presence throughout the New Holocene period. The abundance and distribution of Primulaceae pollen suggests enduring resilience and adaptation within the local ecosystem. Furthermore, the study highlights a significant correlation between changes in vegetation patterns and human cultivation practices, underscoring anthropogenic influences on regional flora dynamics. The prevalence of Primulaceae palynomorphs across soil layers underscores the plants adaptability to varying environmental conditions. Human activities, particularly cultivation practices, emerge as key drivers shaping vegetation dynamics in the Elbasan region. The consistent presence of Primulaceae palynomorphs underscores their resilience amidst changing environmental dynamics. Human intervention emerges as a significant determinant of regional vegetation patterns, highlighting the intertwined relationship between human activities and plant evolution.

Influence of spatial variability of soil shear-wave velocity considering intralayer correlation on seismic response of engineering site

Shear-wave velocity uncertainty significantly impacts seismic response analysis at engineering sites. Previous studies focused on the correlations of shear-wave velocities within soil layers. However, the influence of the vertical spatial variability of shear-wave velocity within individual soil layers was not considered. This study selected a typical Site Class II engineering site to investigate this influence based on the equivalent linear seismic response analysis method of layered soil deposits. Existing field test data on shear-wave velocity were used to discretize the shear-wave velocity within soil layers into a one-dimensional (1D) random field through covariance matrix decomposition and local average process theory. Monte Carlo simulations generated random shear-wave velocity profiles with different vertical correlation distances. Three artificial records with different earthquake return periods were used as input motions at the engineering bedrock for the 1D free-field model. Considering soil shear-wave velocity uncertainty, the peak shear strain increased by 19–27% with the input ground motion amplitude. Moreover, the site peak shear strain variability increased by 25–34% with the vertical correlation distance. The proposed 1D random field model effectively simulated the interlayer correlation and spatial variability of shear-wave velocity within soil layers, demonstrating its significance in seismic response analysis.

Hyper KANAKO System을 활용한 토석류 피해 저감을 위한 계통적 사방대책의 평가

Understanding the local and regional topography and land use of an area is crucial to prevent debris flow recurrence sites caused by heavy rainfall. Scientific techniques, such as numerical modeling, are available for effective planning of management measures and predicting potential debris flow deposition sites from future rainfall events because they consider topography and land use. Quantitative evaluation results were produced by determining the arrangement, size, and type of check dams and modeling debris flow mitigation in the Hyper KANAKO system. The results revealed the original catchment had an increased vulnerability to soil erosion, transport, and deposition compared to the catchment with check dams. Furthermore, the systemic arrangement of check dams proved to be effective in reducing debris flow deposits when compared to a standalone arrangement. Future research is necessary to improve the erosion control planning, maintenance, and evaluation processes. The numerical model and resulting data from this study will be effectively utilized in decision-making by stakeholders to reduce the risk of future sediment-related disasters.

Measurements of Shear Wave Velocity for Collapsible Soil

This paper examines the effects of collapsible soil structure on shear wave velocity. The study attempts to simulate hydraulic fill sand deposits, which represent a natural soil deposition process that can result in a collapsible soil structure. A series of resonant column tests and bender element tests on Ottawa sand was conducted on sand specimens and prepared by dry pluviation and simulated hydraulic fill methods subjected to various confining pressures. Shear wave velocities measured from both methods of deposition are compared and discussed. Results from this study show that for soil specimens with the same void ratio, samples prepared by simulated hydraulic fill have a lower shear modulus and shear wave velocity than the specimens prepared by dry pluviation, and the differences are more pronounced at higher confining pressures. The resonant column test results performed in this study were consistent with results from the discrete element analysis, full-scale testing, and centrifuge testing. The discrete element analysis suggests that soil fabric and number of particle contacts are the key factors affecting the shear wave velocity. These factors are dependent on the methods of deposition. Results from this study examining hydraulic fill collapsible structure shear wave velocity provide a step forward toward a better correlation between soil dynamic properties measured in field and laboratory tests.

Shelterbelt effects on soil redistribution on an arable slope by wind and water

Soil erosion is the most severe form of land degradation globally. Farmland shelterbelts are important for reducing erosion, especially erosion caused by the co-occurrence of water and wind. However, few studies have focused on how the distance from the shelterbelt associated with farmland topography affects the redistribution of soil quality indicators. The aims of this study is to reveal the relative importance of these two factors to soil quality under typical wind and water erosion conditions concurrent with the Songnen Plain, China. Topsoils (0–10 cm) were sampled at seven distances from the shelterbelt with three replicates, where topography heterogeneity was also considered. We found that the silt/clay content and soil nutrients at sites farther from the shelterbelt were significantly greater than those at sites closer to the shelterbelt (P < 0.05). Similarly, deposition was dominant at sites farther from the shelterbelt and downslope positions, while erosion was dominant at sites closer to the shelterbelt and upslope positions. Moreover, we discovered that the relative influence of distance from the shelterbelt and farmland elevation varied with individual soil quality indicators. Soil nutrients increased through the deposition of more fine-textured soil (silt/clay) positions farther from the shelterbelt. The downslope region responds to soil deposition by enhancing the plough pan thickness and lowering the bulk density and pH. Overall, distance from the shelterbelt and farmland elevation had interactive effects on soil quality, and erosion was primarily affected by distance from the shelterbelt (63.4 %), followed by elevation (22.7 %). Furthermore, the sites closer to the shelterbelt (i.e., 20 to 420 m) warrant particular attention due to the deposition of coarse-texture materials here. This work is crucial for an improved understanding of the synergistic effects of long-term water and wind co-occurrence on soil quality evolution.

LIQUEFACTION-INDUCED DAMAGE IN THE CITIES OF ISKENDERUN AND GOLBASI AFTER THE 2023 TURKEY EARTHQUAKE

&amp;lt;p&amp;gt;On February 6th 2023 two major earthquakes struck southeast Turkey, M7.7 Kahramanmaras and M7.6 Elbistan, respectively. Unfortunately, due to the impact of these catastrophic events more than 50 000 casualties and 35 000 collapsed buildings have been reported since then. The aim of the study is to demonstrate preliminary site response analysis and assessment of re-liquefaction potential of sites which have been affected by the earthquakes &amp;amp;ndash; especially the cities of Iskenderun and Golbasi. Both site-specific areas have clear evidences of liquefaction and lateral spreading events which imply the focus of the presented paper. A series of geophysical MASW and microtremor tests have been performed in order to determine shear wave velocities up to depth of 30 m as well as the fundamental natural frequency of the soil deposits.&amp;amp;nbsp;&amp;lt;/p&amp;gt; &amp;lt;p&amp;gt;Moreover, samples have been collected from sand and silt ejecta in order to evaluate some basic physical properties &amp;amp;ndash; grain-size curves, specific gravity and plasticity parameters. On the basis of the obtained data seismic classification of the investigated sites according to current design codes has been made and in-depth distance to relatively stiff layer has been assumed. For the sake of evaluating risk of re-liquefaction the widely-used simplified stress-based approach to triggering assessment has been adopted considering some rules of the thumb (e.g., sieve analysis and plasticity properties evaluation). Lastly, post-liquefaction reconsolidation settlement and lateral displacement have been determined in terms of future earthquakes&amp;lt;/p&amp;gt;