Soil Layer Research Articles

A Study on the Borehole Wall Stability Analysis and Slurry Ratio Optimization for Construction of Pile in Complex Marine Strata.

In order to address the issue of hole collapse, which frequently arises when boring piles are being constructed in intricate marine strata, this paper discusses the influence of the slurry ratio on the slurry performance as well as the mechanism of slurry wall protection. It performs this by means of theoretical analysis, laboratory ratio testing, engineering analogies, numerical simulation, and field testing. Our findings demonstrate that adding sodium polyacrylate and sodium carboxymethyl cellulose can enhance mud's viscosity, contribute to flocculation, and improve the connection between mud and soil layers. Refering similar engineering cases, three optimization schemes are proposed for achieving a mud ratio that offers wall protection in complex marine strata. Furthermore, the particle flow model of slurry viscous fluid is established. The collapse of holes in the sand layer is reflected in the uneven radial displacement of hole walls and the invasion of mud particles. Increasing the viscosity of mud gradually transforms the uneven radial deformation of pore walls in the sand layer into a uniform radial deformation, whereas increasing the proportion of mud significantly decreases the radial displacement of hole walls. Additionally, when the mud pressure in the hole is 300 kPa and 600 kPa, the wall protection effect is better, and there is no particle penetration by substances such as sand. It is found that a high mud pressure can promote the diffusion of mud particles into the sand layer, while low mud pressure cannot balance the pressure on deep soil. The results of the field tests show that the ratio of water-clay-bentonite-CMC-Na-sodium carbonate = 700:110:90:1.5:0.5 used (where the mass percentage of each material is 77.8% water, 12.2% clay, 10% bentonite, 0.16% CMC-Na, and 0.05% sodium carbonate) can effectively prevent hole collapse and reduce the thickness of the sand layer at the bottom of the hole by 50%.

Salinity distribution in agricultural land by geophysical, hydrochemical and geostatistical approaches: a pilot area located in Qelabshowah–Belqas, East Nile Delta region, Egypt

The study area is situated in the Qelabshowah–Belqas region, known for its Quaternary deposits. This research aims to demonstrate the two-dimensional (2D) variation of subsurface layers and salinity distribution using geoelectrical data, hydrochemical analysis, and geostatistical analysis. DC resistivity measurements were taken at fifteen vertical electrical sounding (VES) survey points using a Schlumberger array (AB/2 = 100 m) along three profiles. In addition, an electrical resistivity tomography (ERT) survey was conducted with a dipole–dipole array across one profile. Seven surface water samples were collected in the area. From the 1D and 2D inversion of VES and ERT data sets, three-to-four geoelectric layers were identified, including unconsolidated surface deposits, saturated clayey sand, saturated sand, and a salt-rich layer. The 2D inversion of VES data revealed an ancient salt-rich layer deposited in swampy conditions over a conductive wet sand layer along profile one due to salt mineral infiltration and dissolution. The 2D inversion of ERT data showed accurate lateral geometric accuracy compared to the 2D inversion of VES data, highlighting geological features, such as caves in the second layer and a buried water canal on the ground surface. Surface water samples showed high salinity levels with sodium hazards, indicating an Na–Cl composition. Geoelectric and hydrochemical data sets were geostatistically analyzed using spherical variogram supported ordinary Kriging interpolation. The analysis indicated weak to moderate spatial dependency for true resistivity parameters, while sodium content (SC) and permeability index (PI) showed strong spatial correlation. The 2D spatial distribution resistivity maps based on the 1D inversion of VES data displayed a general decrease in resistivity with depth, likely due to clay minerals or moist soil in the second layer and saline irrigation water infiltration in the third layer. The 2D spatial distribution of SC and PI showed a high concentration zone, posing a potential risk to agricultural crops regardless of soil permeability. It is recommended to use these maps when cultivating plants that can tolerate high sodium levels during the reclamation process.

Analysis of laterally loaded floating piles using a refined Tajimi model

AbstractThis paper presents a novel mathematical model for the analysis of laterally loaded floating piles embedded in a homogeneous soil layer of finite thickness. The governing equations of the soil surrounding the pile are established by treating soil as a Tajimi‐type continuum, and their solution yields a closed‐form expression that provides the lateral force developing to resist pile deflection. Accordingly, analytical expressions are obtained for the swaying, swaying‐rocking and rocking pile head stiffness, as well as for pile displacement and rotation along its length. The derived expressions are functions of parameters that have direct physical meaning, such as pile and soil elastic stiffness. As such, they pose as an attractive alternative to numerical methods for the low‐cost calibration of Winkler‐based model empirical parameters associated with small pile deflections. The presentation concludes with a parametric study focused on exploring the sensitivity of pile stiffness and deformations to the main problem parameters, and on highlighting differences in the lateral response of floating and end‐bearing piles.

STATE-OF-THE-ART APPLICATION OF THE LOG-PILING METHOD IN THE ROLE OF SHALLOW GROUND IMPROVEMENT FOR LIQUEFACTION MITIGATION

<p>This research paper focuses on evaluating the log piling technique as a sustainable, cost-effective, and environmentally friendly solution for reducing soil liquefaction risks during earthquakes. Although this method has been used extensively in Japan, mainly aiming for complete soil layer penetration, its economic viability is questionable in cases requiring very deep soil improvements. The study highlights that shallow ground improvement can notably enhance the seismic behavior of the soil-improvement-structure system, as evidenced by the reduced total and penetration settlements caused by liquefaction. The paper presents a methodology for determining the optimal dimensions of the modified ground zone using both small and medium-scale 1-g shaking table tests. </p> <p>The small-scale tests involve a detailed parametric study, examining variables like improvement width, pile spacing, and the depth-to-thickness ratio of the improved layer. Medium-scale tests, on the other hand, are geared towards identifying the minimum effective pile length. This approach provides a practical guideline for engineers to implement log piling for small residential buildings. Additionally, the paper utilizes finite element method (FEM) effective stress analysis, incorporating a PLAXIS 2D-based constitutive model (PM4Sand) calibrated with laboratory undrained cyclic torsional tests. This model accounts for the changes in effective stress during seismic activities. Finally, the study correlates its numerical findings with the results from the 1-g shaking table experiments, offering a well-rounded perspective on the effectiveness of log piling in mitigating liquefaction risks during seismic events</p> <p> </p>

Stability Analysis of Seismic Slope Based on Relative Residual Displacement Increment Method

The seismic stability analysis of a slope is a complex process influenced by earthquake action characteristics and soil mechanical properties. This paper presents a novel seismic slope stability analysis method using the relative residual displacement increment method in combination with the strength reduction method (SRM) and the actual deformation characteristics of the slope. By calculating the relative displacement of the key point inside the landslide mass and the reference point outside the landslide mass after each reduction, the safety factor of the slope is determined by the strength reduction factor (SRF) corresponding to the maximum absolute value of the relative residual displacement increment that appears after a continuous plastic penetration zone. The method eliminates interference caused by significant displacement fluctuations of key points under earthquake action and reduces the subjective error that can occur when manually identifying displacement mutation points. The proposed method is validated by dynamic calculations of homogeneous and layered soil slopes and compared with three other criteria: applicability, accuracy, and stability.

Organic fertilizer substituting 20% chemical N increases wheat productivity and soil fertility but reduces soil nitrate-N residue in drought-prone regions.

Organic fertilizer substitution is an effective measure for increasing both the quantity and quality of wheat grain while reducing chemical fertilizer input. However, the effects of reducing nitrogen (N) fertilizer combined with organic fertilizer substitution on grain yield, grain protein content and protein yield, plant N accumulation and translocation, N use efficiency, soil fertility, N apparent surplus and nitrate-N residue in rain-fed drought-prone areas remains limited. In this study, field experiments were conducted over four consecutive seasons (2019-2023) at two sites with four treatments: zero N application (ZN), farmer N application (FN), reduced 20% N of FN (RN), and organic fertilizer substituting 20% N of RN (OSN). The results showed that compared with the ZN treatment, the FN, RN and OSN treatments increased grain yield and its components, grain protein content and protein yield, aboveground N accumulation at the anthesis and maturity stages, pre-anthesis N translocation, post-anthesis N accumulation, N use efficiency, soil fertility. Compared with RN and FN, OSN increased grain yield by 17.12% and 15.03%, grain protein yield by 3.31% and 17.15%, grain N accumulation by 17.78% and 15.58%, and N harvest index by 2.63% and 4.45% averaged across years and sites, respectively. Moreover, OSN increased the contents of organic matter, total N, available P and available K in both 0-20 and 20-40 cm soil layers, decreased N apparent surplus and nitrate-N residue in 0-100 cm, and pH in both 0-20 and 20-40 cm soil layer. Fundamentally, this study suggests that integrating a 20% reduction N from conventional farmer practices with the utilization of organic fertilizer to replace 20% of the chemical N fertilizer (OSN) represents an effective strategy. This approach shows promise in enhancing wheat grain yield, grain protein yield, and N use efficiency. Additionally, it supports the improvement of soil fertility while simultaneously reducing soil nitrate-N residues and the apparent surplus of N in rain-fed drought-prone regions.

Simulation of soil temperature under maize: An inter-comparison among 33 maize models

Accurate simulation of soil temperature can help improve the accuracy of crop growth models by improving the predictions of soil processes like seed germination, decomposition, nitrification, evaporation, and carbon sequestration. To assess how well such models can simulate soil temperature, herein we present results of an inter-comparison study of 33 maize (Zea mays L.) growth models. Among the 33 models, four of the modeling groups contributed results using differing algorithms or “flavors” to simulate evapotranspiration within the same overall model family. The study used comprehensive datasets from two sites - Mead, Nebraska, USA and Bushland, Texas, USA wherein soil temperature was measured continually at several depths. The range of simulated soil temperatures was large (about 10–15 °C) from the coolest to warmest models across whole growing seasons from bare soil to full canopy and at both shallow and deeper depths. Within model families, there were no significant differences among their simulations of soil temperature due to their differing evapotranspiration method “flavors”, so root-mean-square-errors (RMSE) were averaged within families, which reduced the number of soil temperature model families to 13. The model family RMSEs averaged over all 20 treatment-years and 2 depths ranged from about 1.5 to 5.1 °C. The six models with the lowest RMSEs were APSIM, ecosys, JULES, Expert-N, SLFT, and MaizSim. Five of these best models used a numerical iterative approach to simulate soil temperature, which entailed using an energy balance on each soil layer. whereby the change in heat storage during a time step equals the difference between the heat flow into and that out of the layer. Further improvements in the best models for simulating soil temperature might be possible with the incorporation of more recently improved routines for simulating soil thermal conductivity than the older routines now in use by the models.

Assessment of Axial Resistance of Piles Considering Consolidation Setup and Aging Setup Using Direct Pile Cone Penetration Test Methods

This paper focuses on evaluating the increase in axial pile resistance subjected to both consolidation and aging setups. Consolidation and aging setup models were first developed to estimate the setup parameters based on databases collected from literature, which include 10 instrumented piles for consolidation setup and 26 test piles for long-term aging. The eight top-performing pile cone penetration test (CPT) methods that were evaluated in a previous study were used to estimate the side resistance of soil layers at 14 days after pile driving. The developed consolidation and aging setup models were then used to extrapolate the results to evaluate the side resistance of each soil layer at the end of consolidation and for long-term aging. The estimated side and total resistances were compared with the measurements from pile load tests considering both consolidation and aging setups. The resistances estimated before and after completion of excess pore water pressure dissipation indicates that significant aging takes place after consolidation setup. The value of consolidation setup parameter ( Ac) was 0.53, and, for aging, the setup parameter ( Ag) was 0.23 in clay and 0.16 in sand. The results show that all pile CPT methods with/without using a consolidation setup model tend to underestimate the unit side resistance of clay soil layers. The use of pile CPT methods in combination with an aging model improved the accuracy of pile CPT methods, and this was verified using load test results for five piles subjected to aging. The Philipponnat and University of Florida (UF) methods showed the best performance on estimating the total resistance of piles subjected to aging.

Soil-Microbial CNP Content and Ecological Stoichiometry Characteristics of Typical Broad-Leaved Tree Communities in Fanjing Mountain in Spring

This study aims to investigate the impact of diverse forest stand types and soil depths on soil ecological stoichiometry characteristics, shedding light on nutrient limitations and cycling patterns within the mid-subtropical forest ecosystem in southwest China during spring. The research focused on four representative forest stands situated in Fanjing Mountain: Castanopsis fargesii (C. fargesii), Cyclobalanopsis multiervis (C. multiervis), Cyclobalanopsis argyrotricha (C. argyrotricha), and Rhododendron argyrophyllum Franch (R. argyrophyllum). Sample plots were established in these forest types, and soil samples were collected from the 0–20 cm and 20–40 cm soil layers in March, spring of 2023. Various soil parameters, including pH, soil organic carbon (SOC), total nitrogen (TN), total phosphorus (TP), soil microbial biomass carbon (MBC), soil microbial nitrogen (MBN), and soil microbial phosphorus (MBP) were measured, and their stoichiometric ratios were calculated. The findings of the study were as follows: (1) In the 0–20 cm soil layer, C. argyrotricha exhibited the highest soil organic carbon, followed by C. fargesii, C. multiervis, and R. argyrophyllum with the lowest content. No significant differences in soil organic carbon were observed among the four forests in the 20–40 cm soil layer. Additionally, C. argyrotricha displayed a significantly higher soil C:N ratio compared to other forest types in different soil layers. In the typical broad-leaved forest area of Fanjing Mountain, the TP was classified as deficient. (2) In the 0–20 cm soil layer, the MBC of C. fargesii surpassed C. multiervis, C. argyrotricha, and R. argyrophyllum by 26.59%, 42.92%, and 24.67%, respectively. There were no significant differences in soil MBC:MBP ratio and MBN:MBP ratio, regardless of forest species and soil depths. The low availability of soil nitrogen in different forest stand types in Fanjing Mountain strongly limits soil microorganism biomass. (3) The correlation between SOC, TN, TP, and their stoichiometric ratios varied across different soil layers. Therefore, in managing the Fanjing Mountain forest area, attention should be paid to supplementing N and P in the soil.

Predicting the ultimate bearing capacity of spudcan in stiff-over-soft clay based on a failure model varying with soil parameter

A jack-up platform is prone to a ‘punch-through’ accident when working on the stiff-over-soft clay foundation. To assess the risk of punch-through, it is necessary to plot the bearing capacity-penetration curve for evaluating the penetration depth of the pile leg or to calculate the ultimate bearing capacity of the spudcan and compare it with the preload. However, accurate prediction of spudcan bearing capacity is not easy. In this paper, the failure mode about the stiff-over-soft clay under different geological conditions when punch-through occurs is discussed using coupled Eulerian lagrangian (CEL) method, varying the strength ratio between soft and stiff soil layers, the thickness of stiff soil relative to the spudcan diameter, and the non-homogeneity factor of soil strength. Based on the soil failure model with varying soil parameters, a new calculation method for ultimate bearing capacity of spudcan is proposed and then verified against existing centrifuge test results. The results show that the shape of soil shear plane in stiff clay is significantly affected by the strength ratio of soil layer and the non-homogeneity factor of soil strength. And the presented new method whose prediction errors compared with centrifuge test results are less than 5%, has better calculation accuracy than the ISO (International Organization for Standardization) method, which is valuable in guiding the calculation of the ultimate bearing capacity of the spudcan and ensuring the safe operation of the jack-up drilling units on stiff-over-soft clay.

Tree water uptake patterns across the globe.

Plant water uptake from the soil is a crucial element of the global hydrological cycle and essential for vegetation drought resilience. Yet, knowledge of how the distribution of water uptake depth (WUD) varies across species, climates, and seasons is scarce relative to our knowledge of aboveground plant functions. With a global literature review, we found that average WUD varied more among biomes than plant functional types (i.e. deciduous/evergreen broadleaves and conifers), illustrating the importance of the hydroclimate, especially precipitation seasonality, on WUD. By combining records of rooting depth with WUD, we observed a consistently deeper maximum rooting depth than WUD with the largest differences in arid regions - indicating that deep taproots act as lifelines while not contributing to the majority of water uptake. The most ubiquitous observation across the literature was that woody plants switch water sources to soil layers with the highest water availability within short timescales. Hence, seasonal shifts to deep soil layers occur across the globe when shallow soils are drying out, allowing continued transpiration and hydraulic safety. While there are still significant gaps in our understanding of WUD, the consistency across global ecosystems allows integration of existing knowledge into the next generation of vegetation process models.

Long-Term Effects of Different Tillage Systems and Their Impact on Soil Properties and Crop Yields

The scientific aim of this article is to elucidate the effects of various tillage practices on soil properties and crop yields; additionally, it seeks to highlight the significant potential of specific farming systems in enhancing soil organic carbon, thereby positively influencing CO2 emissions from soil. In the experimental station of Vytautas Magnus University, Kaunas District, Lithuania (54°52′50″ N and 23°49′41″ E), a long-term field experiment has been established since 1999, and studies have been conducted since 2003. The soil of the experimental site is classified as Epieutric Endocalcaric Planosol (Endoclayic, Episiltic, Aric, Drainic, Endoraptic, Uterquic), according to the World Reference Base (WRB, 2022). Two primary factors were assessed. Factor A incorporated practices of straw removal versus straw chopping and spreading, while Factor B evaluated a spectrum of tillage techniques: conventional deep plowing and two no-tillage practices, one of which involved cover crops. The findings from this long-term study highlight a significant increase in SOC stocks across all treatments over the 20-year period. Notably, the no-tillage practices, coupled with the spreading of chopped straw, demonstrated the most substantial growth in SOC levels, particularly in the top 0–10 cm soil layer. This trend underscores the effectiveness of minimizing soil disturbance and incorporating organic matter in boosting SOC stocks. The different tillage systems influence CO2 emissions from soil. Initially, direct sowing into uncultivated land, both with and without cover crops, led to a notable reduction in CO2 emissions compared to conventional plowing. However, this effect was found to vary over the growth cycle of the plant, highlighting the dynamic interaction between tillage practices, soil properties, and environmental conditions. Collaborative research efforts that involve farmers, scientists, policymakers, and other stakeholders are crucial for the development of holistic, practical, scalable solutions that enhance the sustainability and productivity of agricultural systems. This study contributes to the growing body of knowledge on sustainable agriculture, providing insights for farmers, agronomists, and policymakers in their quest to promote environmentally sound and productive agricultural systems.

Investigation on ground vibration displacements induced by high-speed trains moving on elastic-plastic multi-layered ground by 2.5D FEM

Considering the soil as nonlinear material, the ground vibration displacements caused by high-speed train (HST) moving on the elastic-plastic multi-layered ground are investigated using a 2.5-dimensional finite element model (2.5D FEM), in which the improved Mohr-Coulomb model and the post-Eulerian integration algorithm are also introduced. The accuracy of the established model is validated with published data. Results show that, under different train speeds, the ground vibrations at the track center for the multi-layered soil media are predominantly affected by the properties of the topsoil layer. The ground vibration displacements within 2 m from the track center are controlled by resonance conditions. The displacement attenuation curves fluctuate more in the soft layer than the hard one when the train speed reaches or exceeds the Rayleigh wave speed of all soil layers. Additionally, increasing the elastic modulus of topsoil can effectively reduce the ground vibration displacements in the range of 0.0 m–2.5 m from the track center, and the effects of buried depth for the soft soil layer being slight and thus ignorable.

Analysis of Landslide Handling With Mini Pile Reinforcement Using Plaxis Software on The “X” Toll Road Project

The Semarang-Demak Toll Road faces geotechnical problems due to geological conditions that include hilly areas and basins, with bedrock such as claystone, shale, and lignite that are prone to weakening. A landslide occurred at the Semarang-Demak Toll Road site between Sta. 1+250 and Sta. 2+715, despite various methods of embankment work that were not entirely successful, therefore causing damage. The analysis showed a discrepancy between the theoretical factor of safety and the actual landslide condition, requiring slope reinforcement technology such as mini piles that effectively inhibit soil movement. Mini piles, in the form of reinforced concrete with a length of 7 to 10 meters and a spacing of 2 meters between piles, plus the use of geotextiles, analyzed using the Plaxis 2D program showed an increase in the factor of safety. Although there were slight differences between the reinforcement models, the combination of mini piles and geotextiles proved effective, especially when placed in hard soil layers or over soft soil at a depth of 7 meters from the surface, overcoming the embankment loads at the site.

Alfalfa Cultivation Patterns in the Yellow River Irrigation Area on Soil Water and Nitrogen Use Efficiency

Establishing lucerne field is an efficient way to protect natural steppes, alleviate conflicts between meadows and livestock, and promote the development of animal husbandry. However, problems such as extensive field management, valuing yield over quality, and low resource utilization are endemic in production. Exploring reasonable cultivation patterns can contribute to improving the current situation of artificial grassland production and promoting the high-quality development of husbandry and prataculture. Lucerne the field experiment was carried out in Jingtai, Gansu Province, China in 2021–2022; this study compared and analyzed the effects of three cultivation patterns—ridge tillage with plastic film mulching (PM), ridge tillage with biodegradable film mulching (BM), and traditional flat planting (FP)—on soil water, heat, and fertilizer, as well as lucerne growth, yield, quality, and water and nitrogen use efficiency. The results show that: (1) during the growth period of lucerne, PM and BM treatments augment the average moisture content of the soil layer of 0–120 cm by 31.19% and 24.03% compared to the FP treatment, respectively. In the soil layer of 0–40 cm, PM and BM treatments abate the soil moisture content of the ridges by an average of 19.29% and 7.89% compared to that in the ditches, respectively. In the soil layer of 40–120 cm, PM and BM treatments elevate the soil moisture content of the ridges by 4.40% and 4.65% on average compared to that in the ditches, respectively. The average soil temperature in a soil layer of 5–25 cm shows PM > BM > FP. In contrast with the FP treatment, PM and BM treatments increase the soil temperature of the ridges by an average of 1.87 °C and 0.96 °C and decrease that of the ditches by an average of 0.47 °C and 0.46 °C, respectively. After two years of planting, the three cultivation patterns all promote the soil nutrient content. Compared to the FP treatment, PM and BM treatments increase the organic matter content by 9.94% and 19.94%, respectively. (2) Ridge tillage with film mulching can evidently stimulate the growth of lucerne and enhance yield and quality. Compared to the FP treatment, PM and BM treatments enhance plant height by an average of 15.37% and 4.04%, stem diameter by an average of 34.14% and 14.58%, yield by an average of 21.20% and 14.77%, crude protein content by an average of 13.47% and 7.68%, and relative feed value by an average of 8.71% and 4.41%, respectively. (3) During the two-year growing period, the irrigation amount of lucerne was 508.60–615.30 mm, and the evapotranspiration was 563.70–761.80 mm. Compared to the FP treatment, PM and BM treatments hoist water use efficiency by an average of 43.50% and 17.56%, nitrogen partial factor productivity by an average of 21.20% and 15.22%, and net income by an average of 14.78% and 11.05%, respectively. In summary, in ridge tillage, both ordinary film mulching and biodegradable film mulching can create a favorable soil environment for lucerne growth and heighten production effect. The former has a better effect on advancing the lucerne production effect, and the latter exhibits superior performance in improving soil fertility.

Automatic Object Detection in Radargrams of Multi-Antenna GPR Systems Based on Simulation Data for Railway Infrastructure Analysis

Ground-penetrating radar (GPR) is a non-invasive technology that uses electromagnetic pulses for subsurface exploration. In the railroad sector, it is crucial to assessing soil layers and infrastructure, offering insights into soil stratification and geological features and aiding in identifying subsurface hazards. However, the automation of radargram analysis is impeded by the lack of ground truth—accurate real-world data used to validate machine learning models—thus affecting the deployment of advanced algorithms. This study focuses on generating high-quality simulated data to address the shortage of real-world data in the context of object detection along railroad tracks and presents a fully automated pipeline that includes data generation, algorithm training, and validation using real-world data. By doing so, it paves the way for significantly easing the future task of object detection algorithms in the railway sector. A simulation environment, including the digital twin of a GPR antenna, was developed for artificial data generation. The process involves pre- and post-processing techniques to transform the three-dimensional data from the multichannel GPR system into two-dimensional datasets. This ensures minimal information loss and suitability for established two-dimensional object detection algorithms like the well-known YOLO (You Only Look Once) framework. Validation involved real-world measurements on a track with predefined buried objects. The entire pipeline, encompassing data generation, processing, training, and application, was automated for efficient algorithm testing and implementation. Artificial data show promise for better performance with increased training. Future AI and sensor advancements will enhance subsurface exploration, contributing to safer and more reliable railroad operations.

Cryogenic Pits and Quaternary Glacial Evidence in Central Iran

Quaternary glaciation studies in Central Iran reveal that it is not implausible to anticipate glaciation traces in this region. It is feasible to provide conclusive evidence about the behavior of ice sheets by referring to geomorphological factors and climatic statistical analyses. Factors such as flatness and accidental geographical features contribute to the existence of ice sheets in the Namdan Fars region. The digital reconstruction of past climatic conditions، using the Wright method، along with the absence of lake terraces around Kaftar Lake، signifies the presence of ice instead of water in the lake. The multi-axial morphology of the Namdan Plain، the shape and form of main valleys and passes، and the existence of numerous glacial cirque traces in the surrounding heights are also indicators of this phenomenon. The lack of evidence of ancient settlements in the plain، despite the availability of water and fertile soil، can be attributed to the region's historical thermal conditions. Investigating ancient glaciers helps us understand the natural history of the land. This knowledge can aid planners in devising macro strategies for regional development and water resource management، as glacial performance has always been associated with optimal water levels. Although glacial activities can create aquifers، the movement of ice sheets or ice surfaces does not support the accumulation of sediments required for creating aquifers with sufficient water storage. Instead، their performance leads to the creation of suitable agricultural soil layers. In summary، regional glaciers play a positive role in transforming and creating favorable agricultural soils and can be beneficial in adapting to climatic changes and extending statistical periods.

Analysis of Landslide Handling With Mini Pile Reinforcement Using Plaxis Software on The “X” Toll Road Project

The Semarang-Demak Toll Road faces geotechnical problems due to geological conditions that include hilly areas and basins, with bedrock such as claystone, shale, and lignite that are prone to weakening. A landslide occurred at the Semarang-Demak Toll Road site between Sta. 1+250 and Sta. 2+715, despite various methods of embankment work that were not entirely successful, therefore causing damage. The analysis showed a discrepancy between the theoretical factor of safety and the actual landslide condition, requiring slope reinforcement technology such as mini piles that effectively inhibit soil movement. Mini piles, in the form of reinforced concrete with a length of 7 to 10 meters and a spacing of 2 meters between piles, plus the use of geotextiles, analyzed using the Plaxis 2D program showed an increase in the factor of safety. Although there were slight differences between the reinforcement models, the combination of mini piles and geotextiles proved effective, especially when placed in hard soil layers or over soft soil at a depth of 7 meters from the surface, overcoming the embankment loads at the site.

Root hairs facilitate rice root penetration into compacted layers

Compacted soil layers adversely affect rooting depth and access to deeper nutrient and water resources, thereby impacting climate resilience of crop production and global food security. Root hair plays well-known roles in facilitating water and nutrient acquisition. Here, we report that root hair also contributes to root penetration into compacted layers. We demonstrate that longer root hair, induced by elevated auxin response during a root compaction response, improves the ability of rice roots to penetrate harder layers. This compaction-induced auxin response in the root hair zone is dependent on the root apex-expressed auxin synthesis gene OsYUCCA8 (OsYUC8), which is induced by compaction stress. This auxin source for root hair elongation relies on the auxin influx carrier AUXIN RESISTANT 1 (OsAUX1), mobilizing this signal from the root apex to the root hair zone. Mutants disrupting OsYUC8 and OsAUX1 genes exhibit shorter root hairs and weaker penetration ability into harder layers compared with wild type (WT). Root-hair-specific mutants phenocopy these auxin-signaling mutants, as they also exhibit an attenuated root penetration ability. We conclude that compaction stress upregulates OsYUC8-mediated auxin biosynthesis in the root apex, which is subsequently mobilized to the root hair zone by OsAUX1, where auxin promotes root hair elongation, improving anchorage of root tips to their surrounding soil environment and aiding their penetration ability into harder layers.

Soil Moisture Profiles of Ecosystem Water Use Revealed With ECOSTRESS

AbstractWhile remote sensing has provided extensive insights into the global terrestrial water, carbon, and energy cycles, space‐based retrievals remain limited in observing the belowground influence of the full soil moisture (SM) profile on ecosystem function. We show that this gap can be addressed when coupling 70 m resolution ECOsystem Spaceborne Thermal Radiometer Experiment on Space Station retrievals of land surface temperature (LST) with in‐situ SM profile measurements. These data sets together reveal that ecosystem water use decreases with depth with 93% of sites showing significant LST coupling with SM shallower than 20 cm while 34% of sites have interactions with SM deeper than 50 cm. Furthermore, the median depth of peak ecosystem water use is estimated to be 10 cm, though forests have more common peak interactions with deeper soil layers (50–100 cm) in 37% of cases. High spatial resolution remote sensing coupled with field‐level data can thus elucidate the role of belowground processes on land surface behavior.