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The occurrences of various illegal activities on beaches require effective geological and environmental investigation methods. Among these methods, the room‐temperature magnetic analysis of soils and sediments represents a nondestructive investigation method for various amounts, types, and grain sizes of magnetic minerals. Here, to verify the usefulness of magnetic analysis in forensic geology research, beach sediment samples from nine sites in the Shimokita Peninsula, Japan, were measured using magnetic analysis to determine the correlations between their concentration‐dependent magnetic parameters and actual regional characteristics. The results revealed that the values of various parameters, namely the low‐field magnetic susceptibility, anhysteretic remanent magnetization, and isothermal remanent magnetization (IRM), were relatively higher at sites near Ti and Fe sedimentary ore deposits. Further, thermomagnetometry results revealed that magnetite was the main magnetic carrier of the sediments. Moreover, pyrrhotite was detected around Ti–Fe mine sites. Furthermore, the results of the investigated parameters reflected the regional characteristics of the amount of magnetic minerals in the beach sediments. Low‐temperature IRM curves and the magnetic grain size parameter also displayed sample‐site‐reflective characteristics. Thus, we believe that magnetic analysis represents an effective method for estimating the provenance of beach sediments in forensic geology research. [ABSTRACT FROM AUTHOR]

To comprehensively consider the influence of boundary conditions, non‐Darcy flow, load forms, and soil stratification on soil consolidation, a one‐dimensional soil consolidation equation is established. By subdividing the soil layer and employing time discretization, the nonlinear consolidation equation is linearized, resulting in an analytical solution for layered soil foundation at any given time. Subsequently, an iterative approach for time solution is employed to obtain a semi‐analytical solution. The correctness of the solution is verified by comparison with solutions based on Darcy's flow and the semi‐analytical method under traditional drainage boundary conditions. Subsequently, the influence of interface parameters, loading conditions, flow index, and other factors on consolidation characteristics is analyzed. The results indicate that higher interface parameter values for continuous drainage boundaries correspond to faster average consolidation rates for stratified soil foundations, while these parameters have little effect on the time required for complete consolidation of the soil layers. Improved boundary drainage performance amplifies the influence of exponential flow on pore water pressure and average consolidation degree. Conversely, poor boundary drainage performance diminishes the impact of exponential flow on soil consolidation, rendering it negligible. Moreover, faster loading rates accentuate the influence of the flow index on the average consolidation degree defined by pore pressure. [ABSTRACT FROM AUTHOR]

ABSTRACT Specific interactions between bacteria and ectomycorrhizal fungi (EcMF) can benefit plant health, and saprotrophic soil fungi represent a potentially antagonistic guild to these mutualisms. Yet there is little field‐derived experimental evidence showing how the relationship among these three organismal groups manifests across time. To bridge this knowledge gap, we experimentally reduced EcMF in forest soils and monitored both bacterial and fungal soil communities over the course of a year. Our analyses demonstrate that soil trenching shifts the community composition of fungal communities towards a greater abundance of taxa with saprotrophic traits, and this shift is linked to a decrease in both EcMF and a common ectomycorrhizal helper bacterial genus, Burkholderia, in a time‐dependent manner. These results not only reveal the temporal nature of a widespread tripartite symbiosis between bacteria, EcMF and a shared host tree, but they also refine our understanding of the commonly referenced ‘Gadgil effect’ by illustrating the cascading effects of EcMF suppression and implicating soil saprotrophic fungi as potential antagonists on bacterial‐EcMF interactions. [ABSTRACT FROM AUTHOR]

Bare soil mapping is inevitable for the monitoring of soil resources, as it acts as a major indicator of urban development. Although remote sensing based indices are largely used for the delineation of bare soil, their effectiveness has always been a challenge due to overlapping spectral characteristics of the bare soil and built up areas. Recently, built up indices have been employed to increase the accuracy of bare soil mapping, which can induce discrepancies due to lesser sensitivity in smaller patches of bare soil areas in high density urban regions. In this context, modified normalized difference bare soil index (MNDBSI) is developed using a logical combination of index with additional constraint for the precise delineation of bare soil area using Sentinel 2 images. The qualitative and quantitative analyses adopted to evaluate the performance of the MNDBSI revealed an overall agreement value of above 95% and the improvement percentage of MNDBSI over the other indices compared in terms of spectral discrimination index and transformed divergence varied from 8% to 166% and 15% to 97%, respectively, across all study areas. The comparative analyses of results indicate that MNDBSI is an effective alternative to the existing indices for precise bare soil mapping which can be used as a promising indicator of urban expansion. [ABSTRACT FROM AUTHOR]

Establishing connections between soil health indicators and crop performance will help ensure that tests recommended to farmers relate to outcomes of interest. This study assessed the relationship of soybean [Glycine max (L.) Merr] yield with three common soil health indicators: soil organic matter (SOM), permanganate oxidizable carbon (POXC), and autoclaved citrate extractable nitrogen (ACE‐N). These tests were assessed alongside other factors (soil test phosphorus, soil test potassium [STK], mapped clay, planting date, summer precipitation, and location). Soil samples were collected from 457 producer‐managed fields between 2019 and 2021 in Arkansas, Michigan, North Carolina, and Wisconsin. Planting date and yield were reported by producers, while mapped clay and rainfall were determined using publicly available data. Simple linear regression was used to assess the relationship between soil health indicators and yield: the natural log of SOM and POXC were positively associated with soybean yield (R2 = 0.07, p < 0.001; R2 = 0.03, p < 0.001), while ACE‐N was not (p = 0.872). Multiple linear regression was used to further test the relationship of SOM and POXC with yield, while accounting for other factors that contribute to soybean yield. Models explained 27% of variation in yield, with significant factors including SOM or POXC, soybean planting date, STK, and mapped clay. Based on standardized coefficients, planting date was the most influential factor associated with yield. Broadly, our results indicate that improvements in yield are linked to higher SOM, but management decisions like planting early are critical for achieving high yields. [ABSTRACT FROM AUTHOR]

Translation abstract Numerical analysis of soil vibrations due to vibrating foundations: Guidance for model designGeotechnical engineers are increasingly concerned with wave propagation problems. Manufacturers of geotechnical analysis software added features for soil dynamic analyses to their products initially devised for static geotechnical analyses. Though, users often lack the experience for conducting such advanced numerical analyses. Working groups 1.4 “Soil dynamics” and 1.6 “Numerical analyses in geotechnical engineering” of DGGT German Society for Geotechnical Engineering established a joint subgroup “Numerical analyses in soil dynamics” to address this shortcoming. The present paper presents the work of the subgroup so far and provides some guidance on conducting numerical analyses in soil dynamics. [ABSTRACT FROM AUTHOR]

The study of whether life exists, is extinct, or not depends on various sophisticated experimental studies, as many different signatures of life can be used. The experimental procedures that can be performed to identify life can be further restricted by time, resources, and mobility constraints. Therefore, any research analyzing the presence of extraterrestrial life must be precise and unambiguous. This research focuses on the objective of the extraterrestrial life detection domain and seeks to provide an efficient protocol that can produce life detection decisions based on empirical data obtained through chemical analysis under time and resource-constrained conditions. While the majority of existing frameworks in this field are designed to identify biomolecules, our goal is to accomplish the same with minimal operational expense and mission complexity. We argue that the thoughtful integration of multiple biomolecular detections with lesser complexity and a robust framework can improve overall mission performance by satisfying the necessary time and resource constraints. In this study, a rapid multiple biomolecules-based life detection protocol (MBLDP-R) from soil samples is developed from scratch and embedded in an operational scientific rover subsystem targeted for planetary analysis missions. The study uses artificial biomolecule samples and simulated extraterrestrial environments to illustrate the suggested protocol's end-to-end process. First, we list a few significant biomolecules, including lipids, proteins, carbohydrates, nucleic acids, ammonia, and pigments. Then, a weighted qualitative test scoring is applied to sort out the best test method for the finally selected biomolecules which are used as operational analogue to showcase the protocol's in-situ analysis and decision-making capabilities. Based on the suitable biomolecules, a scientific exploration subsystem is developed, and the implemented protocol is built to perform onboard sample analysis. Evaluation results show that: (1) the proposed MBLDP-R protocol could effectively predict the classes with an average f1-score of 98.65% (macro) and 90.00% (micro), (2) the area under the Receiver Operating Characteristics (AUC-ROC) curve shows the sample categories to be correctly predicted 92% of the time (97% for Extant, 88% for Extinct, and 92% in the case of NPL), and (3) the protocol is time-efficient with an average completion time of 17.60 min, demonstrating the protocol's rapid nature in detecting biosignatures in soil samples. The research outcome yields useful additional data for related future studies, particularly in the design of scientific frameworks for mission-specific requirements with limited resources while also serving as a reference point for constraint evaluation methods for similar systems. [ABSTRACT FROM AUTHOR]

Accurate measurement of metal concentrations in soil and water is vital for healthy crop production and decision making for environmental surveys. While there are a multitude of laboratory‐based soil analysis methods, such as inductively coupled plasma‐optical emission spectroscopy (ICP‐OES), flame emission spectrometry, and atomic absorption spectroscopy, most are time and resource intensive. Additionally, there is a lack of information for rapid analysis of elements for aqueous soil extractions. The goal of this research is to establish elemental correlations between portable X‐ray fluorescence (pXRF) measurements of Mehlich III soil extractions and traditional elemental measurements via ICP‐OES. We hypothesize that certain metals can be accurately measured in aqueous soil extraction solutions by pXRF to the same degree as they are measured by ICP‐OES. To test this hypothesis, Mehlich III and 2% nitric acid solutions with known elemental concentrations were analyzed via ICP‐OES and pXRF. Soil samples extracted using Mehlich III were compared between ICP‐OES and pXRF to verify correlations. High correlations were found for As, Ca, Cd, Cr, Cu, Fe, Mn, Mo, Ni, Pb, Se, V, and Zn in both the Mehlich III and 2% nitric acid solutions at concentrations between 5 and 85 mg L−1. P, S, and Si did not show high correlations at concentrations <100 mg L−1. These results indicate that between 5 and 85 mg L−1, pXRF analysis of aqueous solutions and soil extractions is a reliable technique; however, at low concentrations (i.e., <5 mg L−1 for metals and <100 mg L−1 for P and S), pXRF is not well suited. Core Ideas: There is a significant lack of data validating portable X‐ray fluorescence (pXRF) values for aqueous soil extractions.Acidic and Mehlich solutions yielded an average correlation of >0.998 between pXRF and inductively coupled plasma‐optical emission spectroscopy for heavy metals.Mehlich III extractable Fe and Zn from soil was accurately measured by pXRF.pXRF is not a suitable technique for P, S, or Si <100 mg L−1.pXRF is a suitable method for metal analysis of aqueous soil extractions from 5 to 85 mg L−1. Plain Language Summary: Accurate measurement of nutrients in soil is important for farmers to grow healthy crops. There are many laboratory‐based analysis methods, but these require large amounts of time and resources. Thus, a method that can provide data quickly is important for increasing access to scientific results. The goal of this research is to determine if Mehlich III soil extractions analysis using portable X‐ray fluorescence (pXRF) is comparable to inductively coupled plasma‐optical emission spectroscopy (ICP‐OES). We hypothesize that pXRF and ICP‐OES measurement of certain elements in Mehlich III will be similar. To test this hypothesis, samples with known elemental concentrations were created and analyzed with ICP‐OES and pXRF. Mehlich III extracted soil samples were also analyzed to verify correlations. High correlations were found for 13 elements at concentrations between 5 and 85 mg L−1. These results indicate that between 5 and 85 mg L−1, pXRF analysis of soil extraction solutions is a reliable technique. [ABSTRACT FROM AUTHOR]

A major challenge to implementing effective soil health assessments is how to distinguish the effects of management from underlying soil variability driven by inherent soil properties. This challenge has important consequences for the use of soil health indicators as tools for monitoring and assessment because soil‐forming factors constrain the range of indicator values and the magnitude of management‐induced changes. Here, we present results from a statewide survey of 15 soil health indicators measured on 30 fields on commercial farms across four major land resource areas in Minnesota. Fields included in the study differed in tillage, cover crop implementation, and crop rotation. Within each field, we collected samples from upper and lower hillslope positions to quantify the effect of topography. We consistently detected differences in soil health indicators between regions (13/15 indicators) and hillslope positions (8/15 indicators). However, only wet aggregate stability was sensitive to management across regions and years, highlighting the importance of physical indicators of soil health. This result was surprising in light of existing literature supporting the sensitivity of many soil health indicators to management, but it is consistent with other studies conducted in high organic matter soils in the Upper US Midwest. Our results highlight the need for regionally representative datasets to guide the development of interpretations and benchmarks for soil health indicators. This is particularly important when soil health indicators are applied outside traditional research contexts (such as in commercial soil health testing), where interpretation must take place without the benefit of historical baseline data. [ABSTRACT FROM AUTHOR]

The grouted gravel pile is a new method of pile foundation, which has been widely used in engineering fields in recent years. However, the grout diffusion characteristics and full-field displacement response of soil during grouting have not been fully revealed and systematically studied in previous publications. This paper employed a transparent soil model test system to explore the effects of the grouting pressure (GP), soil pre-consolidation pressure (SPCP), and initial viscosity of grout (GIV) on the grouting performances and load-bearing characteristics of grouted gravel piles. The development laws of the grouting duration, displacement field of the soil, and ultimate load-bearing capacity of the pile were analyzed. The results show that the total grouting duration decreases with a higher GP, increases with the increasing GIV, initially increases and then decreases as SPCP increases. Both the range of horizontal and vertical displacements of the soil around the pile and the distribution of vertical displacements of the soil at the pile end were obviously enlarged with GP as well as with GIV. However, with the increasing SPCP, they showed a decreasing tendency. The vertical ultimate load-bearing capacity of the grouted gravel pile increases with GP, SPCP, and GIV to varying degrees. The findings of this study contribute to the understanding of the pile-soil interaction during grouting process of the grouted gravel pile, which may improve the design of construction parameters. [ABSTRACT FROM AUTHOR]

The one-dimensional consolidation analysis of clays considering creep compression is a classical issue in soil mechanics and geotechnical design. The major debate lies in how to predict the consolidation settlement for a thick layer in the field using parameters obtained from a thin specimen from the laboratory. Different hypotheses have been advocated, based on which various methods and constitutive models have been developed. However, there are still some questions unaddressed and concepts inconsistently used, which may mislead engineers in the selection of methods/models and may result in settlements underestimated on a risk design side. In this paper, a state-of-the-art review and a thorough comparison study are performed on the existing methods and models for the consolidation analysis of clays exhibiting creep, from theoretical derivations to numerical simulations in comparison with soil test data. An in-depth discussion is carried out on several key issues related to the thickness effects on the time-dependent compression behaviour of clays. The arguments of Hypothesis A and Hypothesis B are revisited based on the current development of constitutive theories. Three existing elastic visco-plastic (EVP) models that consider the creep compression implicitly during the whole consolidation process can perform well in predicting the settlement of clay layers with different thicknesses, and are in line with Hypothesis B. It is concluded that using existing EVP models based on porous-media continuum mechanics is a rigorous scientific method (also called "rigorous" Hypothesis B method), which is superior to the old Hypothesis A method which has logic errors and may result in unsafe underestimation of settlements. [ABSTRACT FROM AUTHOR]

The dynamic effects in soil water retention curves (SWRCs) have been the focus of much research. However, most studies implemented short column tests in a few centimeters, under which a semi-permeable porous media inevitably minimizes or magnifies the dynamic effects. In this study, full-scale sand column tests were conducted to eliminate this flaw by preparing a saturated zone under the unsaturated one. The soil suction and moisture profiles were monitored using high-precision tensiometers and spatial time-domain reflectometry, thereby providing a rational overshooting range of the dynamic SWRC. The results confirm that the dynamic primary drainage curve overshoots the static one. The dynamic effects were estimated quantitatively from the soil moisture re-equilibrium time (τS) and dynamic coefficient (τp), falling within reasonable ranges from previous studies. The τp increases log-linearly with decreasing moisture content and can be estimated well from the corresponding τS and the first derivative of SWRC. Also, the τp increases as the soil becomes finer and better graded, which agrees with more-prominent dynamic effects for lower-permeability reservoirs from petroleum studies but disagrees with more-significant dynamic effects for higher-permeability sand from soil-hydrology studies. The analysis shows that the dynamic effects are not dominated solely by the τp or permeability but also by the groundwater dynamics, which can be seen as a pressure boundary from the saturated zone. This finding explains the significant dynamic effects for both high- and ultra-low-permeability geomaterial. Therefore, the present full-scale soil column setup with a prepared saturated zone is recommended for academic investigations of dynamic SWRCs. [ABSTRACT FROM AUTHOR]

A test plot of 15 ha in area has been set as a climate monitoring facility in Shchelkovo district, Moscow oblast, in 2022. Within the boundaries of the test plot, which represents one forest survey unit, a significantly diverse soil cover has been revealed, i.e., 18 soil varieties ranging from subtype to subspecies. Microrelief is considered to be the main factor of carbon stock heterogeneity: the soils of closed depressions occupied by sphagnum mosses differ significantly in carbon stocks in the litter and in the upper 10 cm of soil. For the rest of the territory, the main factors influencing the carbon stock are the percentage of physical clay in the illuvial part of the soil profile, as well as the composition and phytomass of ground vegetation. The highest variation coefficient in C stocks (40%) was registered for the 10–30 cm layer, being due, above all, to the varying thickness of the genetic horizons composing it. Geospatial analysis allows us to pass to the spatial assessment of variation in soil properties and further modeling and forecasting the carbon stock dynamics taking into account the spatial heterogeneity of the territory. Identifying the factors that control carbon stocks in soils will help to work out modeling scenarios aimed at developing measures on increasing carbon accumulation in forest ecosystems through changes in the vegetation structure. [ABSTRACT FROM AUTHOR]

This study evaluates the possible agricultural application of calcium carbonate derived from niobium extraction. This carbonate is stored in dams, and it is enriched with radionuclides from 232Th series, which imposes restrictions on its use. Activity concentration evaluation in soil was performed before the tillage of lettuce (Lactuca sativa L.) and the soil–plant transfer factor was determined. Results showed the dilution factor applied to the carbonate in the soil causes insignificant increments in soil activity concentration. In cultivated lettuce, high activity concentrations of 228Ra and 226Ra were found independently when using either the control or carbonate amended soil. [ABSTRACT FROM AUTHOR]

Clayey soils that exhibit swelling and shrinkage behaviour have paved the way for various engineering problems such as foundation failure, slope stability issues, failure of earthen dams, cracking of clay liners, etc. The shrinkage behaviour of soil is often quantified by employing various direct and indirect experimental techniques to establish the Soil Shrinkage Curve (SSC), a relationship between soil volume change and moisture content. However, SSC can reveal only the overall volume change and does not exclusively comprehend the variation of volumetric shrinkage in linear and radial directions. Hence, a series of desiccation tests were performed on marine and inland clayey soils of different consistencies to evaluate the contribution of volumetric shrinkage in these orientations. From this study, it has been observed that the linear component of volumetric shrinkage was higher for soil samples with a consistency state between 1.0 and 1.5 times the liquid limit. However, the radial component of volumetric shrinkage was found to be higher at the end of the desiccation test for soils with an initial moisture content at or below the liquid limit. Furthermore, the results obtained from the present study have been utilised to establish the influence of soil properties on radial, linear, and total volumetric shrinkage. [ABSTRACT FROM AUTHOR]

The most species-rich grasslands worldwide are known from the Carpathian Mts and their periphery in East-Central Europe. They occur in forest-steppe regions, transitional between temperate forest and arid steppe biomes. Their climate, largely suitable for forests, raises questions about the origin of these grasslands. Have they been forested in the past, or locally maintained through a disturbance regime? We addressed these questions to contribute to the broader understanding of Holocene dynamics of open habitats in temperate Europe. We employed soil charcoal analysis and soil morphology to reconstruct past representation of woody species with fine spatial resolution. Our study area was Romanian Transylvania, a region renowned for a well-developed forest-steppe. Six soil profiles along a climatic gradient were assessed: four in forest-steppe grasslands, two in grasslands in adjacent forest region (forest grasslands). The results revealed profound differences between forest-steppe and forest grasslands. Forest-steppe profiles showed Phaeozems with low specific anthracomass of woody species and continuous dominance by Juniperus, suggesting a long-term presence of grasslands. Forest grasslands showed Luvisols with higher anthracomass and abundant charcoal of broad-leaved trees, indicating establishment after deforestation. The high radiocarbon ages of charcoals in basal soil horizons point to a glacial origin of soils and the link of forest-steppe grasslands to glacial forests. Siberian hemiboreal forests and related grasslands may be modern analogues of the reconstructed ecosystems, sharing many species with present day forest-steppe. We suggest that disturbances such as fire, herbivore grazing, and human activities have played an important role in shaping the forest-steppe over time, contributing to the formation of today's richest grasslands. [ABSTRACT FROM AUTHOR]

The demand for food is increasing and the use of soil organic amendments in agricultural management practices has been instructed to increase crop yield and reduce dependence on synthetic inorganic fertilizers at low cost to limited resource farmers. However, the effect of organic amendments on the quality and nutritional composition of edible plants has received little attention. Locally available organic amendments (sewage sludge SS, chicken manure CM, cow manure Cow, vermicompost Vermi, and biochar Bio) were chosen to test their impact on field-grown sweet potato, Ipomoea batatas L. yield, root quality, and root nutritional composition. The results indicated that utilizing Cow manure in growing sweet potatoes significantly promoted root yield and root nutritional composition. Cow treatment produced the greatest number of roots compared to Bio, CM, SS, and the control treatments. The results also revealed that the concentrations of vitamin C (260. 3 µg g−1), β-carotene (45.4 µg g−1), soluble sugars (16.7 mg g−1), and total phenols (196.3 3 µg g−1 fresh roots) were greater in the roots of plants grown in Cow compared to the roots of the control treatment. The results indicated the low impact of biochar whereas Cow is recommended for enhancing sweet potato yield and nutritional composition. [ABSTRACT FROM AUTHOR]

Fabric anisotropy is a sought-after micro index to correlate macro mechanical responses of granular materials. In this work, the discrete-element method is utilised to simulate multi-directional bender element tests in granular soils to obtain the evolution of wave velocities during drained conventional triaxial (CT) and true triaxial (TT) tests; the contact normal-based fabric is simultaneously monitored for bridging the fabric anisotropy and wave velocity anisotropy. The results show that stress-normalised wave velocities and microscopic fabric, including contact normal distribution and coordination number, remain nearly constant until a stress ratio threshold is reached. After the threshold value is reached, stress-normalised wave velocities start to decrease, especially in the minor principal stress direction, accompanied by significant adjustment of coordination number and fabric anisotropy. The results also reveal that the normalised wave velocity depends on the contact normal densities in the wave propagation and particle oscillation directions. With the contact normal distribution represented by a density function, a good linear relationship between the microscopic fabric anisotropy and macroscopic wave velocity anisotropy is obtained for both CT and TT tests. [ABSTRACT FROM AUTHOR]

Recent earthquakes in New Zealand and Japan showed that pre-shaking histories significantly affected the reliquefaction resistance of soils. In this study, a series of experimental tests was conducted to elucidate the coupled effects of inherent and induced anisotropy on reliquefaction resistance of Toyoura sand, which have not been studied before. Accordingly, loose and dense Toyoura sands were prepared with two different methods: dry deposition and moist tamping. The specimens were sheared cyclically using a hollow cylinder torsional shear apparatus under various cyclic stress ratios up to different residual shear strains (γres) and reconsolidated at different states. The experimental results were assessed from various perspectives, including stress–strain relationships, failure mechanisms, liquefaction/reliquefaction resistance, excess pore water pressure (EPWP) generation and compressibility in conjunction with micromechanical interpretations. It was shown that fabric evolution affects the reliquefaction characteristics of Toyoura sand substantially. Interestingly, a unique correlation exists between EPWP and shear strain accumulation for all tests. An energy-based model was developed to uniquely correlate the dissipated energy with the cyclic resistance based only on residual shear strains; this model shows great promise to develop a unified, energy-based criterion for quantifying the liquefaction/reliquefaction resistance of soils with different fabrics. [ABSTRACT FROM AUTHOR]

Aril paleness is a physiological disorder that might be related to genetics, climate, and orchard management, and is progressed to negatively influence the quality of pomegranates in Iran. The final fruits are not economically valuable for costumers and not exportable. Thus, the present research investigated the intensity of aril paleness disorder in different cultivars including Shisheh Kab, Malas-e-Saveh, and Malas-e-Yazdi cultivated in Birjand, Southern Khorasan, Iran. Treatments included spraying potassium sulfate concentrations of 0 (control), 3 and 5% at late summer (exactly at aril color change stage) on trees for two consecutive years. Fruit and aril weight, anthocyanins, and phenols significantly increased on treated fruit compared to control. Comparison among cultivars indicated that the lowest amounts of quality parameters were observed in Shisheh Kab. Considering the multiple variables that affect the severity of the aril paleness, attention to cultivar type, climate, and the use of nutritional elements based on the soil and leaf analysis was recommended. [ABSTRACT FROM AUTHOR]

The main purpose of this study was to improve the accuracy and reliability of nutrient analysis on soilless substrates by comparing two different saturated medium extract (SME) methods, using either water (SMEW) or DTPA (diethylenetriamine-pentaacetic acid, SMED) as extractants. A series of analyses were performed to compare ion levels quantified from either SMEW or SMED. Substrate pH, electrical conductivity (EC) and nutrient data were analyzed from a survey of substrate components (coconut coir, peat, bark, perlite, vermiculite), and blended greenhouse propagation substrates using the SMEW and SMED methods. In addition, a series of SMEW and SMED extracted samples were sent to three commercial soil testing laboratories for nutrient analysis. The objectives of these analyses were to (1) validate that published relationships between SMEW and SMED methods were consistent with correlation curves for pH, EC and nutrient levels across a wide range of soilless substrates, (2) compare statistical variability of results from SMEW and SMED methods and (3) compare variability in results between different laboratories. The results validated that previously published standards for interpreting SMEW extractions can be used for SMED method for macronutrients and EC due to an approximately 1:1 relationship for test results between extraction methods. Up to 2 orders of magnitude higher levels of micronutrients were extracted for iron (Fe), manganese (Mn), zinc (Zn), and copper (Cu) using SMED compared with SMEW, with low correlation between extractants. Concentrations of ions from SMED extractions were less variable than SMEW for micronutrient analysis but were comparable for macronutrient analysis. Results from this study were combined with published research to provide suggested ranges using SMED for soilless substrates. [ABSTRACT FROM AUTHOR]

Concrete pipes both reinforced and unreinforced still serve as efficient subsurface infrastructure, especially when used as culverts and sewer lines. In which its structural performance greatly affected by pipe-soil interaction through installation types. In this study the effect of concrete bedding on the behavior of buried unreinforced concrete pipe is investigated through full-scale experimental testing program which the concrete pipes are embedded in gravelly sand soil that is loose and dense. With thickness of 30 cm over pipe crown and subjected to different surface loadings. Seven standard 300 mm internal diameter precast unreinforced concrete pipes were evaluated in a lab soil box test facility. Two loading conditions are used, namely earth fill that simulated by a uniform loading platform, and wheel load that simulated using a patch loading platform with dimensions of 254×508 mm2 (10×20 in.2), which is used by AASHTO to mimic the wheel load of an HS20 truck. The results demonstrated that controlled installation utilizing dense compaction granular backfill could achieve 70% of the pipe strength acquired by employing the typical concrete bedding of the indirect design approach. For concrete bedding under patch loads, the greatest bedding factor (ratio between the supporting strength of buried concrete pipe to the three-edge bearing test strength) obtained is 4.53. The failure loads of pipes with concrete bedding is greater than pipes with compacted soil bedding by 30% for uniform loading and 43% for patch loading. [ABSTRACT FROM AUTHOR]

To address the engineering problem of wall collapse and destabilization during the construction of the slurry trench wall, the stability of the slurry trench wall under the condition of three-dimensional (3D) unsaturated stable seepage is studied using the upper limit analysis method and in combination with the three-dimensional rotating failure mechanism. The expression of the factor of safety (FS) for the unsaturated soil slurry trench was deduced by the gravity increase method. Additionally, a genetic algorithm was used to search for the minimum FS and the critical slip surface, and the obtained results were compared and validated with existing literature results. The effects of relevant parameters on the stability of the slurry trench under the condition of unsaturated seepage were analyzed in detail. The results of this paper indicated that ignoring the 3D effect of the slurry trench will underestimate the stability of the slurry trench. The presence of suction in unsaturated soil is beneficial to the stability of the slurry trench, and the impact of suction is closely associated with seepage conditions and the characteristics of the soil. The increase in surcharge load can lead to a decrease in the FS, and its effect on slurry trench stability increases with the enhancement of the three-dimensional effect. The impact of different seepage conditions on the sliding surface of the channel wall of clay strata is more significant, while the effect on the trench wall of sand strata is negligible. [ABSTRACT FROM AUTHOR]

As a typical special soil, red clay found in Guizhou Province, China, must be improved before it can be used for projects owing to its high plasticity. As a soil curing agent, the Consolid system is applicable to a wide range of soils, has good improvement effects and a simple operation, and is environmentally friendly. The effects of the dosage and curing age of the Consolid system on the unconfined compressive strength and shrinkage properties of the cured red clay–gravel mixture are studied. The results showed that both these properties of the red clay–gravel mixture were significantly improved by the Consolid System, and the higher the dosage of the Consolid system, the better the improvement effect. The thermal methods of thermogravimetric analysis and differential scanning calorimetry were used to determine that the bound water content was related to the amount of Consolid system admixture. With the increase in the dosage of the Consolid system, the weakly bound water content of red clay appeared to be reduced to different degrees, while the strongly bound water content was reduced to a lesser extent. The reduction in the weakly bound water led to an increase in the molecular gravitational force between the soil particles. This promoted the agglomeration of the soil particles to form a stronger agglomerate structure, thereby enhancing its mechanical properties. The physical phase analysis of cured soils with different amounts of Consolid system admixture was carried out by X-ray diffraction analysis. No chemical reaction occurred during improvement, but the crystal spacing was reduced. This phenomenon could be a factor improving the shrinkage properties. In addition, the shrinkage properties of the soil improved because of the low number of exchangeable cations on the mineral surface, allowing the cured soil to enter a charge equilibrium state quickly. [ABSTRACT FROM AUTHOR]

To enhance our understanding of soil behavior at critical states, considering that natural soil is composed of granular matter, a quasi-static inertia number taking soil compaction into account is proposed. In analyzing classical triaxial test data of soil, the scaling law of quasi-statically deforming grains at the critical state is explored; a simple linear relationship is found between the coefficient of friction and the proposed number. This scaling law describes quantitatively the influence of initial compaction, shear rate, confining pressure, and particle size on the frictional strength of granular soils when they reach the critical state. The number proposed is employed to describe the scaling of volumetric behavior of granular soils undergoing quasi-static deformation. The difference between the particle volume fraction at the critical state and that at the initial compacted state is also found to be linearly correlated with the quasi-static inertia number, for soil at the critical state. [ABSTRACT FROM AUTHOR]

For the characterization of fiber-reinforced soil under static loading conditions, there is a wealth of literature. However, study on the dynamic behavior of fiber-reinforced soil is very limited. Now that earthquakes are occurring frequently around the world, the dynamic soil analysis has become important for all classes of geotechnical engineering problems. Through numerical simulation of triaxial specimens, the current study explores the behaviour of fiber-reinforced cohesionless soil. The numerical model was validated using existing laboratory triaxial compression testing literature. The stress–strain response of fiber-reinforced sand has been investigated using static and cyclic triaxial testing, as well as other combinations of fiber contents. Fiber-reinforced sand is tested for bulk modulus, shear modulus, and damping values. Effects of fiber contents on static and dynamic stress–strain response of fiber-reinforced soil are highlighted. It has been observed from results that, with an increase in fiber content modulus of elasticity, bulk modulus and shear modulus values increase while damping coefficients decrease for the same. It is believed that the highlighted numerical approach will be an alternative to laboratory experiments to determine the dynamic properties of fiber-reinforced soil. [ABSTRACT FROM AUTHOR]

Finding effective phosphorus (P) recommendation strategies to optimize corn (Zea mays L.) yield under varying yield levels and environmental conditions is continuously sought after. A 16‐year study was conducted in Concord, NE, on Nora silt loam soil initially measuring 16 ± 3 mg kg−1 Bray‐1 P. The study evaluated the impact of different P fertilization strategies on corn yield across various growing conditions (dry, normal, and wet years). Treatments included no P or N (NPNN), no P (NP), P applied at crop removal phosphorus (CRP), and maintaining soil P at 15 (B15), 30 (B30), and 45 (B45) mg kg−1 Bray‐1 P, with similar nitrogen (N) rates except for NPNN. Results showed a 25% and 33% reduction in soil test phosphorus (STP) for NPNN and NP treatments, respectively. The total P required by B30 and B45 treatments was 1.8 times more than that for CRP and B15. Although B30 and B45 treatments increased corn grain P concentration by 6%–12% compared to B15 and CRP, they did not increase yields in normal and dry years. The NP led to yield reductions of 9% and 12% in normal and wet years, respectively. In contrast, CRP achieved an 8% higher yield than B15 during wet years. Economic analysis revealed that B45 yielded a 56% higher net return in normal years, while CRP offered the highest return on investment (ROI) at 4.9. This study highlights the complexity of managing soil P under varying environmental conditions, emphasizing that while maintaining higher STP levels (B30 and B45) can enhance grain P concentration, it does not significantly boost yield and ROI compared to CRP and B15. Core Ideas: Applying P based on crop removal increases soil test phosphorus (STP) over time.Continued P application based on crop removal phosphorus (CRP) reduces yield loss risk compared to maintaining soil at critical level (15 ppm Bray‐1 P).High STP levels (>30 Bray‐1 P mg kg−1) increase grain P concentration and removal without consistent yield improvement.CRP‐based application maximizes net income and return on investment compared to maintaining soil at critical P levels. [ABSTRACT FROM AUTHOR]

SoilDoc is a soil testing kit designed to determine site‐specific fertility status and enhance the accessibility of soil test services for smallholder farmers in the tropics. This study aimed to validate the use of the kit in the Southern Highlands (Mbeya and Njombe) and the Eastern Zone (Mvomero) of Tanzania. Composite soil samples collected from 144 smallholder farm fields were analyzed using 0.01 M CaCl2 extraction solution as per SoilDoc protocols. Out of 144 sites, 24 sites were randomly selected for nutrient response trials. The treatments were (i) absolute control, (ii) N alone, (iii) P Low N (Recommended P and half of recommended N), (iv) recommended NP, (v) NPK, (vi) NPS, (vii) NKS, and (viii) NPKS, replicated three times. Maize yields were subjected to analysis of variance. Relative yield for each nutrient applied was subjected to Cate and Nelson procedure to determine critical ranges. Across all sites, the control yielded least (0.55–5.20 Mg ha−1). Application of NPS, NPK, NP, or NPKS produced the highest yield (2.5–6.9 Mg ha−1). The SoilDoc critical ranges were 0.30–0.48 mg P kg−1; 0.15–0.27 cmolc K kg−1, and 4.1–4.8 mg S kg−1. Mbeya and Njombe soils appeared deficient in either NS, NP, NPK, or NPK, while in Mvomero 53% of soils were deficient in N alone and 31% of soils were deficient in NS. In the absence of field‐specific soil tests, applying N, P, S, and K in Mbeya and Njombe and N and S in Mvomero would be best bets for maximizing yield and return on fertilizer investment. Core Ideas: Maize (Zea mays L.) response to applied N, P, K, and S varied with SoilDoc test results.Application of NPS and NPKS resulted in highest maize yield of 2.5–8.8 Mg ha−1.The SoilDoc critical values are 0.30–0.48 mg P kg−1; 0.15–0.27 cmolc K kg−1, and 4.0–4.8 mg S kg−1.Nutrient‐deficiency groups consist of N alone, S alone, NS, NK, NP, NPK, NPS, NKS, and NPKS. [ABSTRACT FROM AUTHOR]

Accurate soil stratification is crucial for levee safety evaluation, yet limited field sampling often hinders comprehensive analysis. This study applies the Partitioning Around Medoids (PAM, also known as K-Medoids) clustering approach for levee soil stratification using data from multiple probe drilling sites. Focusing on a Yellow River levee section in China as a study case, the PAM clustering approach effectively identifies its distinct soil types and reconstructs its soil stratification by analyzing key soil properties relevant to levee seepage and stability characteristics, including coefficient of permeability, angle of internal friction, and cohesion. The resulting soil stratification, when applied to seepage and stability analyses of the levee section, yields relatively high safety factors, indicating low failure risks under design flood conditions. These analytical results align with recent monitoring records, validating the effectiveness of the approach. A sensitivity analysis on the number of clusters, the key parameter in the PAM clustering approach, demonstrates the typical existence of an optimal value balancing computational accuracy and practical interpretability. A comparison with a hierarchical clustering approach further confirms the robustness of the PAM clustering approach. This study contributes to improving levee soil stratification methodology and enhancing levee safety evaluation, particularly when dealing with limited and spatially distributed sampling data. [ABSTRACT FROM AUTHOR]

Soil salinization poses a significant ecological challenge, emerging as a critical constraint to agricultural development in the arid and semi-arid regions of China, especially in southern Xinjiang. In particular, Yuepuhu County, situated in Kashgar, faces a distinctive issue. Impermeable thin clay layers within the vadose zone impede year-round leaching of salts, significantly impacting the growth of cotton. Through a combination of indoor testing, experiments, and statistical analyses, this study elucidated the varying permeability of soil layers at different depths and explored the forms and accumulation characteristics of soil salts in Yuepuhu County. It unveiled patterns of water and salt movement in soils with variable permeability layers, identifying key influencing factors. The research also proposed an irrigation regime suitable for cultivating vadose zone soils in the local context. The findings revealed a progression of increasing soil complexity and decreasing burial depth of clay layers from northwest to southeast, aligned with the direction of groundwater flow. With increasing depth, a noticeable reduction in soil saturated hydraulic conductivity was observed, indicating significant variability in permeability. Predominantly chloride-sulfate type saline soils in Yuepuhu County contained potassium (K+) and sodium (Na+) as the main cations in surface soils. Salinity strongly correlated with calcium (Ca2+) and magnesium (Mg2+). Chloride (Cl−), sulfate (SO42−), K+, Na+, and bicarbonate (HCO3−) reflected the degree of soil salinization in Yuepuhu County. The clay interlayers in variable permeability zones significantly impeded water and salt movement in the vadose zone. Moving from west to east, thicker and shallower clay interlayers hindered downward water movement, increasing the difficulty of salt leaching. Additionally, the irrigation regime influenced water and salt movement in the vadose zone. Under the same soil structure, flood irrigation with a higher water flux resulted in more significant salt leaching, and lower total dissolved solids (TDS) in irrigation water were more favorable for effective salt leaching. Collectively, our findings provided a theoretical foundation for improving and managing local saline soils, as well as guiding the implementation of rational agricultural irrigation practices. [ABSTRACT FROM AUTHOR]

There are many fertilizer additives and alternatives that aim to increase plant nutrient use efficiency and reduce nutrient losses to the environment, here referred to collectively as enhanced efficiency fertilizers (EEFs). However, there is often insufficient published scientific field trial results across a variety of locations, climates, soils, cropping systems, and management scenarios to prove their efficacy and conditions for use. Guidelines for common minimum datasets and data stewardship in evaluating the agronomic performance and environmental impact of EEFs are needed for researchers to follow. Such guidelines will improve hypothesis testing centered on product efficacy and provide producers with guidance on how these technologies function and perform when integrated with other management practices within the 4R Nutrient Stewardship Framework. A scientific committee was formed to develop a set of protocol guidelines for evaluating EEFs in replicated, plot‐based field trials on an international scale. The guidelines are composed of experimental design and core metadata, crop and soil analyses, environmental loss measurements, and data stewardship, and include both recommended and required components to allow for flexibility and adaptability depending on the trial location, objectives, infrastructure capacity, product type, and depth of understanding of the potential EEF efficacy. This approach will ensure consistency and compatibility in experimental design and data collection to support data integration, analysis, and reuse leading to large‐scale impact and end‐user confidence. [ABSTRACT FROM AUTHOR]

AbstractBacillus species and organomineral fertilizers can improve various crop responses. The objective of this study was to evaluate the efficiency of organomineral fertilizer with B. subtilis and B. licheniformis, in comparison to mineral fertilizer, on soybean growth, leaf nutrient content, grain yield, and soil characteristics. Two soybean field experiments (305 km apart) were set up in southeastern Brazil. Two sources of fertilizers (inoculated granulated organomineral, 5-26-0 + 0-0-32 N-P2O5-K2O, and coated mineral fertilizer, 10-52-0 + 0-0-60 N-P2O5-K2O), and four doses of P plus K (no fertilizer, 50, 75, 100 kg ha−1 of each P2O5 and K2O) were applied. At 60 days after sowing, plant height and leaf analysis were assessed. Weight of 1000 seeds, grain yield, and soil analysis were evaluated (120 days after sowing). In both fields, there was interaction between source and P plus K dose factors for soybean grain yield. In Site 1, the highest grain yield (4,543.69 kg ha−1) was observed for 100 kg ha−1 of P2O5 and K2O dose of coated mineral fertilizer; in Site 2, the highest grain yield (4,638.55 kg ha−1) was observed for 75 kg ha−1 of P2O5 and K2O dose of organomineral fertilizer. These factors also affected N, P, and K leaf contents. Less effects were observed on plant height, weight of 1000 seeds, and soil characteristics. Inoculated organomineral fertilizer can be used for total or partial supply of nutrients without a clear difference from mineral fertilization. Smaller doses of inoculated organomineral fertilizer could be used without compromising soybean grain yield. [ABSTRACT FROM AUTHOR]

Biodegradability testing in soil helps to identify safe synthetic organic chemicals but is still obscured by the formation of soil-bound 'non-extractable' residues (NERs). Present-day methodologies using radiocarbon or stable (13C, 15N) isotope labeling cannot easily differentiate soil-bound parent chemicals or transformation products (xenoNERs) from harmless soil-bound biomolecules of microbial degraders (bioNERs). Hypothesizing a minimal retention of hydrogen in biomolecules, we here apply stable hydrogen isotope – deuterium (D) – labeling to unravel the origin of NERs. Soil biodegradation tests with D- and 13C-labeled 2,4-D, glyphosate and sulfamethoxazole reveal consistently lower proportions of applied D than 13C in total NERs and in amino acids, a quantitative biomarker for bioNERs. Soil-bound D thus mostly represents xenoNERs and not bioNERs, enabling an efficient quantification of xenoNERs by just measuring the total bound D. D or tritium (T) labeling could thus improve the value of biodegradability testing results for diverse organic chemicals forming soil-bound residues. Non-extractable residues formation limits biodegradability testing in soil. Here, the authors show that hydrogen isotope tracers are hardly retained in microbial biomass, enabling an efficient distinction between biogenic and xenobiotic residues. [ABSTRACT FROM AUTHOR]

Recently, there has been significant consumer demand for traditional tomato varieties due to their favourable organoleptic qualities; however, the cultivation of these ancient varieties is becoming more restricted due to inadequate shelf life and low productivity. The "Pisanello" is a Tuscany tomato variety mainly cultivated in the provinces of Pisa, Lucca, and Livorno, and the main producers of this ancient tomato are small local farmers. The purpose of this work was, firstly, to study the range of quality parameters of this landrace tomato grown using different cultivation techniques, both in soil and soilless systems. For this purpose, the physicochemical parameters of Pisanello tomatoes grown in six different farms in Tuscany using both soilless and soil methods were investigated. Secondly, Pisanello tomatoes grown using different soilless techniques (rockwool and aeroponics) and soil-grown tomatoes (Pisanello and Goldmar F1) were evaluated from organoleptic and nutraceutical points of view. The sensory profile evaluation of all types of tomatoes under investigation was carried out. The aeroponic cultivation of Pisanello induced higher organoleptic qualities than those of tomatoes cultivated in rockwool (+34% for titratable acidity and +18% for total soluble solids). On the other hand, soilless rockwool-grown tomatoes showed a better sensory profile with respect to aeroponic cultivation. Nevertheless, the Goldmar F1 tomato, morphologically similar to 'Pisanello', received lower scores from the sensory panel compared to the Tuscany landrace tomato. This indicates that ancient tomato varieties selected over decades remain the preferred choice for consumers. Therefore, from a long-term viewpoint, the valorisation of local tomato varieties such as Pisanello can promote the regional commercialization of novel niche products originating from ancient fruit thanks to their acceptability by consumers. [ABSTRACT FROM AUTHOR]

The aim of this study is to carry out a petrological and geotechnical study of the lateritic soils of Ngaoundal (Adamawa-Cameroon). Hence, geotechnical identification, X-ray difractometry, and chemical analysis (XRF) were used to characterize soils. Field investigations show that the average thickness of the lateritic layers is 1.3 m; the soils encountered are nodular with a silty/clay matrix. The dominant color is dark brown (7.5YR 5/6) with a lumpy structure and silty or clayey texture. Mineralogical analysis (XRD) and chemical data (XRF) show that these materials are made up of quartz (38.27%), goethite (13.98%), gibbsite (10.59%), kaolinite (8.62%), hematite (7.88%), magnetite (8.38%), anatase, and boehmite. These soils are silico-ferrugino-aluminous. Their silica/sesquioxide ratios correspond to those of true laterites. X-ray diffraction analysis of the soil samples revealed the absence of swelling clays. Geotechnical analyses indicate that these soils have specific weights between 2.580 and 2.648 g/cm3. The liquidity limits show an average of 54.5%, with an average plasticity index of 29.73%. According to the (HRB) classification, these soils belong to the class of silty/clayey gravels and sands known as A-2–7. The values for maximum dry density and optimum water content range from 2.040 to 2.188 g/cm3 and from 9.5 to 13.6% respectively. The CBR bearing capacity index shows values ranging from 78.0 to 95.1%, which proves that these materials belong to bearing capacity class S5. The geological and geotechnical data confirm that the Ngaoundal materials are suitable for road construction (sub-base and base layers). [ABSTRACT FROM AUTHOR]

This study investigated the performance of the adaptive neuro-fuzzy inference system (ANFIS), feed forward neural network (FFNN), Soil and Water Analysis Tool (SWAT), Hydrologic Engineering Center's Hydraulic Modeling System (HEC-HMS), Hydrologiska Byråns Vattenbalansavdelning (HBV), and support vector regression (SVR) models for rainfall-runoff modeling using gauged and satellite rainfall, and their fusions in the Gilgel Abay watershed, Ethiopia. Afterward, simple average ensemble (SAE), weighted average ensemble (WAE), and neural network ensemble (NNE) techniques were applied to combine the outputs of individual models under three scenarios. The performance of the models was evaluated using Nash-Sutcliffe efficiency (NSE) and root mean square error (RMSE). The results demonstrated that the ANFIS model outperformed all the other single models with validation stage NSE values of 0.864 and 0.875, and RMSE values of 23.58 and 21.84 m3/s for gauge and fusion rainfall data, respectively. Among the physical-based models, SWAT gave better modeling performance with the validation stage NSE values of 0.81 and 0.821 for gauge and fusion rainfall data, respectively. Moreover, an ensemble of artificial intelligence and physical-based models greatly improved the overall modeling performance. The NNE improved the performance of single models up to 15.7 and 21.2 5% for fusion and satellite-based rainfall modeling, respectively. [ABSTRACT FROM AUTHOR]

Nanofertilizers release nutrients slowly and in a controlled manner, matching the plants' growth needs. By reducing the need for chemical inputs such as fertilizers and pesticides, nanotechnology contributes to more sustainable agricultural practices. The present study used nano-urea with Azotobacter on strawberry cv. 'Winter Dawn' under protected cultivation to evaluate its impact on soil fertility status and leaf nutrient content. Formulations as per the treatment requirements were sprayed onto the strawberry plants. The plants provided with nano-urea formulations exhibited enhanced levels of nitrogen (2.49%), phosphorus (0.37%), and potassium (2.60%) compared to the plants treated with conventional urea. Soil nutrient analysis showed enhanced levels of NPK in soil samples from traditional application treatments. A higher concentration of microorganisms in the soil was observed when urea was applied at the nano level. Nano-urea combined with Azotobacter can significantly impact the soil's NPK levels. This innovative blend enhances nutrient availability in the soil and promotes sustainable agricultural practices. By leveraging the nanotechnology-infused urea alongside the nitrogen-fixing process of Azotobacter bacteria, the soil experiences a synergistic boost in nitrogen, phosphorus, and potassium content. This dynamic duo fosters a conducive environment for plant growth while minimizing nutrient leaching and environmental degradation. [ABSTRACT FROM AUTHOR]

Little is known of helminth parasites in Micronesia in archaeological contexts. This study presents a parasitological analysis of soil and sediment samples from Ebon Atoll in the Marshall Islands, eastern Micronesia. Microscopic eggs of the dog (Canis lupus familiaris) nematode Toxocara canis, which could have adversely affected the health of local people as well as their dogs, were found at two sites, in one example in habitation layers dated to 1830–1625 calBP (95% CI), extending the date for the known presence of dogs in the Marshall Islands by at least 600 years. This study represents the first confirmed evidence of pre‐European helminth parasites in Micronesia. As similar Melanesian and Polynesian studies have previously been reported, the study also completes the initial, pre‐contact helminth record for the three main island regions of Oceania. [ABSTRACT FROM AUTHOR]

In this review article, the main techniques for spectroscopic studies of gases in field conditions are considered. The issues related to the study of gas emissions from soils and the determination of their concentrations are analysed. The main types of spectroscopy used in portable devices for soil gas analysis, along with their design features and sampling approaches, are provided. Various studies aimed at optimising the operation of devices for analysing gases emitted from the soil, taking into account agronomic, agrochemical, and ecological specifics, are also presented. The effect of using different types of lasers and reflecting elements on the accuracy of optical measurements and the sensitivity to various substances in the gases is analysed. [ABSTRACT FROM AUTHOR]

This study aims to provide substantial theoretical support for employing vacuum preloading‐airbag pressurization (VP‐AP) to enhance soft soil foundations. By integrating the airbags and prefabricated vertical drains (PVDs) within the analytical framework, the consolidation models are developed to accommodate double smear zones and well resistance. Analytical solutions for various airbag pressurization scenarios are derived under the equal‐strain assumption. A model test is subsequently conducted to investigate the settlement process of soft soil using the VP‐AP method. The validity of the proposed theoretical model is corroborated through comparison with existing analytical solutions and experimental data. The accuracy of the predictive model is further substantiated by the model test results. Lastly, this research offers an in‐depth analysis of soil consolidation behavior under diverse influencing factors. The findings indicate that the VP‐AP method demonstrates superior efficacy over conventional vacuum‐surcharge preloading when the airbag pressure matches the external load pressure. Additionally, an increase in the radius of airbags enhances the soil consolidation efficiency. The analytical model presented in this study elucidates the consolidation mechanisms of the VP‐AP method, with experimental research confirming the efficacy of this approach and the predictive model established herein. [ABSTRACT FROM AUTHOR]

This paper proposes an improved discretization‐based kinematic approach (DKA) with an efficient and robust algorithm to investigate slope stability in nonuniform soils. In an effort to ensure rigorous upper‐bound solutions which may be not satisfied by the initial DKA based on a forward difference method (DKA‐FD), a central and backward difference "point‐to‐point" method (DKA‐CD and DKA‐BD) is proposed to generate discretized points to form a velocity discontinuity surface. Varying (including constant) soil frictional angles along depth are discussed, which can be readily considered in the improved DKA‐CD. Work rate calculations are performed to derive upper‐bound formulations of slope stability number, and critical failure surface is correspondingly obtained at limit state. The comparison with forward and backward difference methods clearly reveals that the improved DKA‐CD could significantly reduce the mesh‐dependency issue and enhance efficacy of slope stability analyses in nonuniform soils. [ABSTRACT FROM AUTHOR]

In this paper, we present the long-term occupation of the Perputxent Valley with the purpose of exploring the factors that could explain the long-lasting and trans-cultural occupation of resilient sites and landscapes for nearly two millennia. The first part describes the archaeological research carried out based on remote sensing and intensive coverage survey methods and geoarchaeological analysis. The characterisation of the intensive agricultural uses has been studied from the geochemical analysis of the soil and sedimentary record. The objective is to reconstruct the palaeoenvironmental processes and the possible evidence of the agricultural practices. This research has identified the residential spaces, the sites and the agrarian land-uses, especially intensive farmlands. The second part analyses the evidence of this long-term settlements in the context of the archaeological, ethnographic and historical record of the region. Understanding these practices of agriculture and land-use can contribute to understandings of what makes societies sustainable. [ABSTRACT FROM AUTHOR]

An experimental campaign is conducted on a 100g centrifuged monopile model, impact driven, into saturated dense sand, down to three embedding depths, corresponding to three slenderness ratios of 5, 4 and 3. These models are instrumented with optical fibres to measure the bending moment profile along the monopile. A new method is developed to determine the experimental soil reaction curves by considering the distributed moment part from the measured bending moment. This distributed moment is assessed by the one-dimensional finite-element (1D FE) model of the PISA (pile soil analysis) method. The key features of this study are: (a) the monopile behaves from pure rotation to combined rotation–flexure as the slenderness ratio is enhanced from 3 to 5, inducing a less pronounced linear rotation–deflection response at ground level; (b) although the distributed moment assessed in the PISA project is very low, the developed method is useful to explore the experimental local behaviour of laterally loaded monopiles; (c) the 1D FE PISA model captures reasonably well the overall behaviour of laterally loaded centrifuged driven monopiles, even if it is less accurate for the local behaviour. [ABSTRACT FROM AUTHOR]

The feasibility of Carrillo's method is confirmed for consolidation problems of unsaturated soils under instantaneous loading in this study. In the plane strain and axial symmetry consolidation models, the coupled governing equations expressed by the excess pore-air and pore-water pressures are transformed into the equivalent uncoupled equations expressed by two functions of excess pore pressure using a decoupled method. Then, two rigorous theorems are used to prove that Carrillo's method is suitable for unsaturated soil consolidation under the plane strain and axial symmetry conditions. Finally, the mathematical formulas by Carrillo's method for unsaturated soil consolidation under plane strain and axisymmetric conditions are presented, and are verified against those of the existing analytical solutions. It turns out that the combinations of existing solutions to the conditions of a single direction flow by the proposed formulas can directly furnish the solutions to unsaturated soil consolidation with both horizontal and vertical flows. [ABSTRACT FROM AUTHOR]

Research on geosynthetic-reinforced soil (GRS) walls in tiered configurations is increasing gaining attention, with numerical methods being predominantly used in the past. In recent years, there has been a growing trend in conducting shaking table tests to further explore this area. However, traditional limit equilibrium (LE) methods are more preferred for design purposes. This study utilized a modified top-down approach, which is based on LE and pseudo-static methods to investigate the horizontal seismic force on the distribution of required tension along each reinforcement layer. The approach is initially extended from static analysis to seismic analysis for multitiered GRS walls. Parametric analyses are conducted to study the impacts that horizontal seismic coefficient, reinforcement length and spacing, internal friction angle of soil, height ratio of upper/lower tier, offset distance have on the internal stability of two-tiered GRS walls. Meanwhile, influences of wall batter and number of tiers on the critical offset distance for different seismic coefficients are assessed. Results indicate that the internal stability differs between the upper and lower tiers under seismic conditions, particularly with higher seismic forces, where the lower tier requires greater reinforcement tension to enhance its stability. Additionally, the critical offset distance grows with the increase in seismic coefficient, and it is sensitive to the internal friction angle of soil and the height ratio. • An approach based on the top-down method which is modified to calculate the distribution of required reinforcement tension of multitiered GRS walls under seismic conditions is proposed. • An in-depth seismic analysis of the internal stability of GRS walls in tiered configurations is first conducted. • Impacts of horizontal seismic coefficient, reinforcement length and spacing, internal friction angle of soil, offset distance, and height ratio of upper and lower tiers are investigated. • The variation of critical offset distance under various seismic coefficients and wall parameters is revealed. [ABSTRACT FROM AUTHOR]

The combination of the best properties of Polycarbonate (PC) and Acrylonitrile-butadiene-styrene (ABS) has resulted in the development of commercially available PC/ABS blends that have been found to be useful in many molding applications. PC has excellent mechanical and optical properties, but predominant use of bisphenol A in PC synthesis raises concerns regarding its potential environmental harm. In this study, we have studied the alternative for the PC/ABS blend by replacing PC with the bio-based PC and ABS with the Acrylonitrile-styrene-acrylate (ASA). A blend of bio-based PC and ASA was prepared by the melt blending techniques and investigated mechanical, thermal, and degradation (hydrolytic and soil burial degradation) properties. [ABSTRACT FROM AUTHOR]

With the purpose of economizing the routine soil testing for micronutrients and avoiding the use of multiple soil extraction procedures, a laboratory investigation was attempted to evaluate a new chemical extractant for assessing the availability of common micronutrients (Fe, Cu, Mn, Zn, Mo, and B) in soils of widely varying properties (n = 32). The new extractant designated as OM-MES-VERA# contained 0.01 M oxalic acid, 0.02 M maleic acid, 0.02 M 2-(N-Morpholino) ethane sulfonic acid (MES), 0.0025 M ethylene diamine tetraacetic acid di-sodium salt, 0.02 M acetic acid, and 0.1% polyacrylamide (final pH adjusted to 6.0). OM-MES-VERA extracted significantly higher amounts of micronutrient cations and B from soils compared to the conventional diethylene triamine pentaacetic acid (DTPA, pH 7.3) extractable micronutrient cations and hot water soluble B, respectively, but lesser amount of Mo compared to Mehlich-3 universal extractant. Soil test values by both OM-MES-VERA- and conventional extractants were correlated with soil properties. The labile (E and L) values of micronutrient cations and Mo estimated by isotopic dilution method, ammonium bicarbonate-DTPA, pH 7.6 extractable soil B (as an estimate of E for B) and B concentration in maize (as an estimate of L for B) were successfully regressed on soil test values of micronutrients by OM-MES-VERA and conventional soil extractants except in the case of DTPA (pH 7.3) for E-value of Fe and L-value of Mn. The OM-MES-VERA extractant can be considered to assess the availability of common micronutrients in soils of diverse soil properties. [ABSTRACT FROM AUTHOR]

A series of plate loading tests on clay has been conducted in the centrifuge. The aim of the tests is to create a data set, which is freely downloadable, to validate numerical tools that account for geometrical nonlinearities. The tests include two sources of geometrical non-linearities. The first source is the reducing clay layer thickness below the plate, which causes an increase in resistance. The second source is the backflow of the clay around the tip of the plate. The backflow has a reducing effect on the plate resistance. This paper outlines four tests: two involving a wide plate and two with a small plate. Each plate geometry is investigated under both smooth and rough side model boundaries. An material point method (MPM) schematization is used for numerical analysis. The schematization and parameter selection are initially validated by comparing the MPM results against CPTu data in each test. The numerical analysis examines the impact of a finite layer thickness by analyzing various layer thicknesses. Furthermore, the analysis shows the influence of the backflow on the plate resistance by analyzing different ratios of shaft to plate width. In this study, the pore pressures below the plate and vertical and horizontal displacement fields are considered in addition to the load displacement curves. The MPM simulations are in good agreement with the centrifuge data. [ABSTRACT FROM AUTHOR]

The escalating trend of land degradation poses a significant challenge, especially in sloping agricultural terrains, driven by the increasing global demand for food and the limited availability of flat arable land. In response to these challenges, farmers are compelled to shift their focus towards cultivating sloping terrains. This research aimed to employ a comprehensive methodology that integrates onsite field surveys, meticulous laboratory soil analyses, and geospatial data for mapping soil erodibility. The parameters under scrutiny encompass various crucial aspects, including soil texture (ranging from coarse sand to very fine sand, silt, and clay), soil structure, organic matter content, and permeability. The meticulous examination of these factors serves as the foundation for calculating soil erodibility, utilizing the well-established Wischmeir and Smith formula developed in 1978. The research findings present a nuanced understanding of soil erodibility in the study location, revealing a spectrum spanning low to very high erodibility. Specific units, such as Unit 1, Unit 2, Unit 3, Unit 7, Unit 9, Unit 10, Unit 13, and Unit 16, exhibit very low to low erodibility. In contrast, Unit 4, Unit 6, Unit 14, and Unit 15 showcase moderate erodibility, while units like Unit 5, Unit 8, Unit 11, Unit 12, Unit 17, and Unit 18 are characterized by moderately high to very high erodibility. These insightful results shed light on the diverse erodibility levels within the studied locations and provide valuable guidance for formulating sustainable land management practices. [ABSTRACT FROM AUTHOR]

Livestock grazing has been proposed as a cost-effective way to reclaim post-mining lands. It can enhance soil fertility and biodiversity, but its impacts on soil quality and microbial communities vary across soil types. Moreover, waste from grazing raises concerns about pathogens that could pose risks to animal and human health. This study investigated the effects of grazing on post-mining perlite-rich soil in central Thailand. A comparative analysis of soil physicochemical properties and bacterial diversity was conducted between grazed and ungrazed sites. Bacterial diversity was assessed using 16S amplicon sequencing. The perlite-rich soil was found to be sandy, acidic, and to have low nutritional content. Grazing significantly improved the soil texture and nutrient content, suggesting its potential as a cost-effective reclamation strategy. The 16S metagenomic sequencing analysis revealed that microbial communities were impacted by livestock grazing. Specifically, shifts in the dominant bacterial phyla were identified, with increases in Firmicutes and Chloroflexi and a decrease in Actinobacteria. Concerns about increased levels of pathogenic Enterobacteriaceae due to grazing were not substantiated in perlite-rich soil. These bacteria were consistently found at low levels in all soil samples, regardless of livestock grazing. This study also identified a diverse population of Streptomycetaceae, including previously uncharacterized strains/species. This finding could be valuable given that this bacterial family is known for producing antibiotics and other secondary metabolites. However, grazing adversely impacted the abundance and diversity of Streptomycetaceae in this specific soil type. In line with previous research, this study demonstrated that the response of soil microbial communities to grazing varies significantly depending on the soil type, with unique responses appearing to be associated with perlite-rich soil. This emphasizes the importance of soil-specific research in understanding how grazing affects microbial communities. Future research should focus on optimizing grazing practices for perlite-rich soil and characterizing the Streptomycetaceae community for potential antibiotic and secondary metabolite discovery. The obtained findings should ultimately contribute to sustainable post-mining reclamation through livestock grazing and the preservation of valuable microbial resources. [ABSTRACT FROM AUTHOR]