Search Results (176)

Tomato (Solanum lycopersicum) production is increasingly threatened by Tuta absoluta, a destructive pest that compromises yield and quality. To explore sustainable alternatives to conventional insecticides, we investigated the jasmonate-mediated defense pathway by performing a genome-wide characterization of the JAZ gene family in S. lycopersicum. A total of 39 SlJAZ genes were identified and mapped to 12 chromosomes. Detailed analysis revealed conserved motifs, diverse exon–intron structures, four major phylogenetic groups, and the presence of multiple MeJA- and stress-responsive cis-elements. Synteny analysis indicated gene duplication events and evolutionary conservation with Arabidopsis and potato. Small RNA predictions suggested that 33 SlJAZ genes are targeted by 69 microRNAs, implying multilayered regulation. Transcriptome analysis under four treatment conditions—mesoporous silica nanoparticles (MSNs) ± pest infestation—revealed 21 differentially expressed SlJAZ genes. SlJAZ1, SlJAZ19, SlJAZ20, and SlJAZ22 were notably upregulated under the combined MSN and pest treatment, with expression patterns validated by qRT-PCR (R² = 0.92). Phenotypic assessment of leaf damage index, larval survival rate, and number of leaf mines showed reduced pest activity in MSN-treated plants. Regression analysis demonstrated significant negative correlations between expression levels of SlJAZ20, SlJAZ26, and SlJAZ29 and pest-related damage traits. These findings indicate that MSNs function as effective elicitors of JA-responsive defense in tomato and modulate the expression of specific JAZ genes linked to enhanced resistance. The study provides a valuable foundation for integrating nanotechnology with molecular defense strategies to promote sustainable pest management. Full article

The stability of open-pit mines under low-temperature conditions is critical for safe and efficient coal extraction. However, the mechanisms of rock damage and fracture under combined temperature and stress effects remain unclear, particularly regarding the evolution of mechanical properties under repeated freeze–thaw cycles and varying peripheral pressures. This study investigates the damage and rupture behavior of coal-bearing sandstone in cold-region open-pit mines through experimental testing and theoretical modeling. The research was conducted in three stages: (1) freeze–thaw and peripheral pressure experiments to evaluate mechanical property evolution; (2) acoustic emission monitoring to analyze internal fracture initiation, propagation, and coalescence under temperature–stress coupling; (3) development of a local deterioration model to quantify post-damage strength decay considering low-temperature erosion and freeze–thaw effects. Results show that increasing freeze–thaw cycles leads to a transition from brittle to ductile behavior, while higher peripheral pressures significantly enhance ductility. Mechanical parameters are highly sensitive to peripheral pressure but largely independent of freeze–thaw cycle count. Acoustic emission signals respond strongly to temperature, and temperature–stress coupling governs the three-stage evolution of fracture germination, extension, and penetration. The local deterioration model effectively captures post-peak residual strength and damage evolution. These findings indicate that in regions with higher microcrack density, fault propagation is driven by rapid coalescence under stress concentration, whereas in lower-density regions, it is dominated by gradual fracture growth and temperature-induced expansion. The results provide theoretical guidance for stability assessment and support design in open-pit coal mines in cold environments. Full article

Mining-induced surface subsidence is a typical geological hazard. Loose layer drainage disturbed by coal mining can exacerbate surface subsidence in terms of both the extent and amount, thereby increasing the risk of building deformation and environmental degradation in mining areas. However, currently the prediction results of surface subsidence considering these two factors are not precise enough, which contradicts the principles of green coal mining. Firstly, this paper introduces the probability integral method, which predicts mining-induced surface subsidence. Subsequently, based on the soil–water coupled theory and the derived characteristic curve of groundwater level decline, a surface subsidence prediction model that considers loose layer drainage is constructed using triple integral transformation. Finally, a more precise surface subsidence prediction model considering both factors is proposed based on the principle of superposition. The model is applied to the mining of working panel 1309 in Shanxi province, China, an area rich in coal yet scarce in water resources. When compared with the measured subsidence data, the proposed model achieves a root mean square error (RMSE) of 27 mm, while the RMSEs of existing models are 78 mm and 123 mm, respectively. The prediction accuracy has been significantly improved. In addition, the proposed model is further validated through fluid–solid coupling numerical calculations in FLAC3D. The subsidence results considering the single effect of each factor also demonstrated good validation accuracy. Overall, the proposed model can accurately describe the surface subsidence considering both factors. This research can provide a theoretical guide for assessing the environmental impact and building damage, while contributing to the sustainable development of land use and groundwater resource in mining areas. Full article

The aim of this study was to determine whether opportunistic citizen science can support the detection of life history traits in invasive insects. Using the invasive leaf-mining micromoth Macrosaccus robiniella (Clemens 1859) (Lepidoptera: Gracillariidae) as a model species, we analyzed data from iNaturalist submitted by citizen scientists to assess the variability in its leaf mines on its native host, Robinia pseudoacacia L., 1753 (Fabaceae), across both the moth’s invaded (Europe, North America–Eastern United States) and native range (North America–Southern and Western Unites States, Eastern Canada). We examined 86,489 photographs collected over the past 20 years to compare the occurrence and proportions of different M. robiniella leaf mine types between invaded and native ranges using three search variants: (I) M. robiniella, (II) all endophagous invasive insects associated with R. pseudoacacia, and (III) the host plant itself. The first two datasets revealed differences in the ratio of leaf mine types between Europe and North America (when analyzed separately for native and invaded areas), whereas the third dataset showed no significant differences in either the presence or proportion of mine types between invaded and native ranges. Leaf mine types atypical of M. robiniella, which resemble damage caused by other invasive insects such as Parectopa robiniella Clemens, 1863 (Lepidoptera: Gracillariidae) and Obolodiplosis robiniae (Haldeman, 1847) (Diptera: Cecidomyiidae)—also associated with R. pseudoacacia—have been observed in Europe for at least a decade. Our main conclusion is that, when investigating the life history traits of invasive herbivorous insects, focusing data collection on the host plant rather than on the insect species alone can reduce biases associated with opportunistic citizen science and help reveal true ecological patterns. Full article

In the mining of deep mineral resources and tunnel engineering, the degradation of mechanical properties and the evolution of energy of through-double-joint sandy slate under triaxial loading and unloading conditions are key scientific issues affecting the stability design of the project. The existing research has insufficiently explored the joint inclination angle effect, damage evolution mechanism, and energy distribution characteristics of this type of rock mass under the path of increasing axial pressure and removing confining pressure. Based on this, in this study, uniaxial compression, conventional triaxial compression and increasing axial pressure, and removing confining pressure tests were conducted on four types of rock-like materials with prefabricated 0°, 30°, 60°, and 90° through-double-joint inclinations under different confining pressures. The axial stress/strain curve, failure characteristics, and energy evolution law were comprehensively analyzed, and damage variables based on dissipated energy were proposed. The test results show that the joint inclination angle significantly affects the bearing capacity of the specimen, and the peak strength shows a trend of first increasing and then decreasing with the increase in the inclination angle. In terms of failure modes, the specimens under conventional triaxial compression exhibit progressive compression/shear failure (accompanied by rock bridge fracture zones), while under increased axial compression and relief of confining pressure, a combined tensioning and shear failure is induced. Moreover, brittleness is more pronounced under high confining pressure, and the joint inclination angle also has a significant control effect on the failure path. In terms of energy, under the same confining pressure, as the joint inclination angle increases, the dissipated energy and total energy of the cemented filling body at the end of triaxial compression first decrease and then increase. The triaxial compression damage constitutive model of jointed rock mass established based on dissipated energy can divide the damage evolution into three stages: initial damage, damage development, and accelerated damage growth. Verified by experimental data, this model can well describe the damage evolution characteristics of rock masses with different joint inclination angles. Moreover, an increase in the joint inclination angle will lead to varying degrees of damage during the loading process of the rock mass. The research results can provide key theoretical support and design basis for the stability assessment of surrounding rock in deep and high-stress plateau tunnels, the optimization of support parameters for jointed rock masses, and early warning of rockburst disasters. Full article

The representation and assessment of static liquefaction in mine tailings is a significant challenge due to the severe environmental and social damage it can cause. This phenomenon, known for its catastrophic nature, is triggered when the undrained shear strength is exceeded by a static loading stress. In this study, the constitutive models HSS and NS were evaluated to calibrate the experimental curves from an isotropically consolidated undrained (CIU) triaxial test on a low-plasticity silt derived from mine tailings. An axisymmetric model was developed in Plaxis 2D for calibration, followed by a sensitivity analysis of the parameters of both constitutive models, using the RMSE to validate their accuracy. The results indicate that the proposed methodology adequately simulates the experimental curves, achieving an RMSE of 8%. After calibration, a numerical model was implemented to evaluate the propagation of the PFS of a mine tailings storage facility using both models, in terms of excess pore pressures, shear strains, and p’-q diagrams at three control points. The results show that both models are capable of representing the PFS; however, the HSS model reproduces the experimental curves more accurately, establishing itself as an ideal tool for simulating undrained behavior and, consequently, the phenomenon of static liquefaction in mine tailings. Full article

Underground blasting vibrations are a critical factor influencing the stability of mine slopes. However, existing studies have yet to establish a quantitative relationship or clarify the underlying mechanisms linking blasting-induced vibrations and slope deformation. Taking the Shilu Iron Mine as a case study, this research develops a dynamic mechanical response model of slope stability that accounts for blasting loads. By integrating slope radar remote sensing data and applying the Pearson correlation coefficient, this study quantitatively evaluates—for the first time—the correlation between underground blasting activity and slope surface deformation. The results reveal that blasting vibrations are characterized by typical short-duration, high-amplitude pulse patterns, with horizontal shear stress identified as the primary trigger for slope shear failure. Both elevation and lithological conditions significantly influence the intensity of vibration responses: high-elevation areas and structurally loose rock masses exhibit greater dynamic sensitivity. A pronounced lag effect in slope deformation was observed following blasting, with cumulative displacements increasing by 10.13% and 34.06% at one and six hours post-blasting, respectively, showing a progressive intensification over time. Mechanistically, the impact of blasting on slope stability operates through three interrelated processes: abrupt perturbations in the stress environment, stress redistribution due to rock mass deformation, and the long-term accumulation of fatigue-induced damage. This integrated approach provides new insights into slope behavior under blasting disturbances and offers valuable guidance for slope stability assessment and hazard mitigation. Full article

The time-dependent creep behavior of coal is essential for assessing long-term structural stability and operational safety in deep coal mining. Therefore, this work develops a full-stage creep constitutive model. By integrating fractional calculus theory with statistical damage mechanics, a nonlinear fractional-order (FO) damage creep model is constructed through serial connection of elastic, viscous, viscoelastic, and viscoelastic–plastic components. Based on this model, both one-dimensional and three-dimensional (3D) fractional creep damage constitutive equations are acquired. Model parameters are identified using experimental data from deep coal samples in the mining area. The result curves of the improved model coincide with experimental data points, accurately describing the deceleration creep stage (DCS), steady-state creep stage (SCS), and accelerated creep stage (ACS). Furthermore, a sensitivity analysis elucidates the impact of model parameters on coal creep behavior, thereby confirming the model’s robustness and applicability. Consequently, the proposed model offers a solid theoretical basis for evaluating the sustained stability of deep coal mining and has great application potential in deep underground engineering. Full article

To explore the influence of mine roof on the damage and failure of sandstone surrounding rock under different pressure rates, mechanical experiments with different strain rates were carried out on sandstone rock samples. The strength, deformation, failure, energy and damage characteristics of rock samples with different strain rates were also discussed. The research results show that with the increases in the strain rate, peak stress, and elastic modulus show a monotonically increasing trend, while the peak strain decreases in the reverse direction. At a low strain rate, the proportion of the mass fraction of complete rock blocks in the rock sample is relatively high, and the shape integrity is good, while rock samples with a high strain rate retain more small-sized fragmented rock blocks. This indicates that under high-rate loading, the bifurcation phenomenon of secondary cracks is obvious. The rock samples undergo a failure form dominated by small-sized fragments, with severe damage to the rock samples and significant fractal characteristics of the fragments. At the initial stage of loading, the primary fractures close, and the rock samples mainly dissipate energy in the forms of frictional slip and mineral fragmentation. In the middle stage of loading, the residual fractures are compacted, and the dissipative strain energy keeps increasing continuously. In the later stage of loading, secondary cracks accelerate their expansion, and elastic strain energy is released sharply, eventually leading to brittle failure of the rock sample. Under a low strain rate, secondary cracks slowly expand along the clay–quartz interface and cause intergranular failure of the rock sample. However, a high strain rate inhibits the stress relaxation of the clay, forces the energy to transfer to the quartz crystal, promotes the penetration of secondary cracks through the quartz crystal, and triggers transgranular failure. A constitutive model based on energy damage was further constructed, which can accurately characterize the nonlinear hardening characteristics and strength-deformation laws of rock samples with different strain rates. The evolution process of its energy damage can be divided into the unchanged stage, the slow growth stage, and the accelerated growth stage. The characteristics of this stage reveal the sudden change mechanism from the dissipation of elastic strain energy of rock samples to the unstable propagation of secondary cracks, clarify the cumulative influence of strain rate on damage, and provide a theoretical basis for the dynamic assessment of surrounding rock damage and disaster early warning when the mine roof comes under pressure. Full article

This study analyzes the impact of the type of transported material (overburden, lignite, mixture) on the rate of core damage accumulation in Type St conveyor belts in open-pit mines. The research was conducted using the DiagBelt+ diagnostic system, which enables the assessment of belt core condition without dismantling the belt. Data were collected from over 100 conveyor belt loops, covering segments of varying lengths, ages, and operational histories. Damage density and area were assessed, and differences were analyzed depending on the material type. The results indicate that belt age and damage density vary significantly with material type, while the Resurs indicator (percentage of expected operating time) shows no clear dependence on the material type. A multiple regression analysis was also performed to predict failure density based on operational variables, such as Age, Resurs results, Loop Length, and Segment Length. The regression model explains approximately 46% of the variability in damage density, indicating the need for further research to improve predictive accuracy. The study emphasizes the importance of using non-destructive diagnostic systems to optimize maintenance planning and enhance conveyor belt reliability. Full article

Land degradation from trace metal pollution in North Africa severely compromises soil fertility. This study investigates the synergistic remediation potential of Eucalyptus biochar (EuB) and Casuarina glauca in iron mine soil contaminated with Fe, Zn, Mn, Pb, Cd, and As. Seedlings were grown for six months in: non-mining soil (NMS), contaminated soil (CS), and CS amended with 5% EuB (CS + EuB). Comprehensive ecophysiological assessments evaluated growth, water relations, gas exchange, chlorophyll fluorescence, oxidative stress, and metal accumulation. EuB significantly enhanced C. glauca tolerance to multi-trace metal stress. Compared to CS, CS + EuB increased total dry biomass by 14% and net photosynthetic rate by 22%, while improving predawn water potential (from −1.8 to −1.3 MPa) and water-use efficiency (18%). Oxidative damage was mitigated. EuB reduced soluble Fe by 71% but increased Zn, Mn, Pb, and Cd mobility. C. glauca exhibited hyperaccumulation of Fe, Zn, As, Pb, and Cd across treatments, with pronounced Fe accumulation under CS + EuB. EuB enhanced nodule development and amplified trace metals sequestration within nodules (Zn: +1.4×, Mn: +2.4×, Pb: +1.5×, Cd: +2.0×). The EuB-C. glauca synergy enhances stress resilience, optimizes rhizosphere trace metals bioavailability, and leverages nodule-mediated accumulation, establishing a sustainable platform for restoring contaminated lands. Full article

Exploiting clay for brick production results in soil damage. There are no field evaluations for its recovery with organic amendments comprising biochar. We conducted a small-scale experiment to assess the recovery effects of soil using biochar, both alone and in combination with compost. On a remnant of soil from clay mining, we applied the following to plots of 2.25 m² in a randomized complete block design: (1) biochar + efficient microorganisms (EMs), (2) compost + EMs, (3) compost + biochar + EMs, and (4) a control group without amendments. Composite soil samples from each plot were collected at the beginning of the experiment and at 30, 120, and 210 days. We analyzed some physicochemical properties of the soil and recorded the number and morphotypes of seedlings. We found that biochar + EMs and biochar + compost + EMs had positive effects in the short term, particularly in reducing bulk density. No synergistic effect was observed between biochar and compost, contrary to what was expected, which may be due to the short term of the experiment and prevailing low temperatures. The compost + EM treatment resulted in greater seedling diversity. In conclusion, bulk density can be used as an early indicator of soil improvement when biochar alone or combined with compost is used. Biochar may be a striking solution for promoting sustainable soil management after clay mining in high-elevation conditions. Full article

As open-pit mining extends to greater depths, slope stability is becoming a critical factor in ensuring safe production. This issue is particularly pronounced in geological settings with weak interlayers, where sudden slope failures are more likely to occur, demanding precise and reliable stability assessment methods. In this study, a typical open-pit slope with weak interlayers was investigated. Acoustic testing and ground-penetrating radar were employed to identify rock mass structural features and delineate loose zones, enabling detailed rock mass zoning and the development of numerical simulation models for stability analysis. The results indicate that (1) the slope exhibits poor overall integrity, dominated by blocky to fragmented structures with well-developed joints and significant weak interlayers, posing a severe threat to stability; (2) in the absence of support, the slope’s dissipated energy, displacement, and plastic zone volume all exceeded the failure threshold (Δ < 0), and the safety factor was only 0.962, indicating a near-failure state; after implementing support measures, the safety factor increased to 1.31, demonstrating a significant improvement in stability; (3) prior to excavation, the energy damage index (ds) in the 1195–1240 m platform zone reached 0.82, which dropped to 0.48 after reinforcement, confirming the effectiveness of support in reducing energy damage and enhancing slope stability; (4) field monitoring data of displacement and anchor rod forces further validated the stabilizing effect of the support system, providing strong assurance for safe mine operation. By integrating cusp catastrophe theory with energy-based analysis, this study establishes a comprehensive evaluation framework for slope stability under complex geological conditions, offering substantial practical value for deep open-pit mining projects. Full article

This study focuses on the alpine meadow ecosystem of the Qinghai–Tibet Plateau, which plays a vital role in carbon sequestration and water resource protection. However, mining activities have severely damaged the ecosystem, posing challenges for ecological restoration. The study selected the Jiangcang mining area and analyzed the physical, chemical, and carbon characteristics and heavy metal content of soil samples from the slag platforms and slopes (0–20 cm), which were restored in 2015 and 2020 to explore the effects of different soil reconstruction methods on soil function and ecological resilience. The results show that the minimum data set (MDS) can effectively replace the total data set (TDS) in assessing soil quality. The assessment indicates good restoration effects in 2020, with some areas rated high in soil quality. Although issues such as high bulk density, high electrical conductivity, low moisture content, nitrogen deficiency, and low organic matter limit ecological restoration, the carbon sequestration capacity of the restored soil is strong. This study provides scientific evidence for ecological restoration in cold mining areas, indicating that capping measures can enhance soil resistance to erosion, nutrient retention, and carbon sink functions. Full article

High temperatures significantly affect the physical and mechanical properties of rocks in deep geoengineering projects, such as geothermal development, deep mining, and the geological disposal of nuclear waste. Therefore, it is essential to explore the relationship between the thermal damage (TD) of granite and its influencing factors. This paper characterizes the TD of granite specimens subjected to high temperatures of up to 800 °C and proposes a predictive model for this thermal damage. A database, which includes publicly available experimental data of advanced microscopic observations of granite specimens exposed to high-temperature treatments and their changes in physical and mechanical properties, was compiled and analyzed. The collected data revealed a consistent trend: crack development among quartz, feldspar, and biotite minerals was observed to intensify notably between 400 °C and 600 °C, as indicated by changes in the mechanical properties. Based on these characteristics, the relationships between TD and its influential parameters were determined using regression models and several machine learning algorithms. The derived models indicated good predictability performance with a coefficient of determination (R²) varying between 0.60 and 0.97, with the boosted ensemble tree model being the best. Nevertheless, mineral contents were not found to be good predictors of TD, even if they control the evolution of the crack during the heat treatment. It was concluded that the findings of this study could serve as a valuable tool for assessing the thermal damage of rocks. Full article