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On December 18, 2023, a magnitude MS6.2 earthquake struck Jishishan County, Gansu Province, triggering over 40 seismic subsidence sites within a seismic intensity VI zone, 32 km from the epicenter.The earthquake caused tens of millions in economic losses to mountain photovoltaic power stations. Extensive geological surveys and comparisons with similar landslides (such as soil loosening, widespread cracks, and stepped displacements) triggered by the 1920 Haiyuan MS8.5 earthquake and the 1995 Yongdeng MS5.8 earthquake, this study preliminarily identifies one subsidence sites as a seismic-collapsed loess landslide. To investigate its disaster-causing mechanism: the dynamic triaxial test was conducted to assess the seismic subsidence potential of the loess at the site, and the maximum subsidence amount under different seismic loads were calculated by combining actual data from nearby bedrock stations with site amplification data from the active source; simulation of the destabilization evolution of seismic-collapsed loess landslides by large-scale shaking table tests; and a three-dimensional slope model was developed using finite element method to study the complex seismic conditions responsible for site damage. The research findings provide a theoretical foundation for further investigations into the disaster mechanisms of seismic-collapsed loess landslides.

期刊论文 2025-12-31 DOI: 10.1080/19475705.2025.2457997 ISSN: 1947-5705

Thawing-triggered slope failures and landslides are becoming an increasing concern in cold regions due to the ongoing climate change. Predicting and understanding the behaviour of frozen soils under these changing conditions is therefore critical and has led to a growing interest in the research community. To address this challenge, we present the first mesh-free smoothed particle hydrodynamics (SPH) computational framework designed to handle the multi-phase and multi-physic coupled thermo-hydro-mechanical (THM) process in frozen soils, namely the THM-SPH computational framework. The frozen soil is considered a tri-phase mixture (i.e., soil, water and ice), whose governing equations are then established based on u-p-T formulations. A critical-state elasto-plastic Clay and Sand Model for Frozen soils (CASM-F), formulated in terms of solid-phase stress, is then introduced to describe the transition response and large deformation behaviour of frozen soils due to thawing action for the first time. Several numerical verifications and demonstrations highlight the usefulness of this advanced THM-SPH computational framework in addressing challenging problems involving thawing-induced large deformation and failures of slopes. The results indicate that our proposed single-layer, fully coupled THM-SPH model can predict the entire failure process of thawing-induced landslides, from the initiation to post-failure responses, capturing the complex interaction among multiple coupled phases. This represents a significant advancement in the numerical modelling of frozen soils and their thawing-induced failure mechanisms in cold regions.

期刊论文 2025-11-01 DOI: 10.1016/j.cma.2025.118252 ISSN: 0045-7825

The Arctic has been warming much faster than the global average, known as Arctic amplification. The active layer is seasonally frozen in winter and thaws in summer. In the 2017 Arctic Boreal Vulnerability Experiment (ABoVE) airborne campaign, airborne L- and P- band synthetic aperture radar (SAR) was used to acquire a dataset of active layer thickness (ALT) and vertical soil moisture profile, at 30 m resolution for 51 swaths across the ABoVE domain. Using a thawing degree day (TDD) model, ALT=K root TDD, we estimated ALT along the ABoVE swaths employing the 2-m air temperature from ERA5. The coefficient (K) calibrated has an R2=0.9783. We also obtained an excellent fit between ALT and K root(TDD/theta) where theta is the soil moisture from ERA5 (R2=0.9719). Output based on shared-social economic pathway (SSP) climate scenarios SSP 1-2.6, SSP 2-4.5, and SSP 5-8.5 from seven global climate models (GCMs), statistically downscaled to 25-km resolution, was used to project the impacts of climate warming on ALT. Assuming ALT=K root TDD, the projections of UKESM1-0-LL GCM resulted in the largest projected ALT, up to about 0.7 m in 2080s under SSP5-8.5. Given that the mean observed ALT of the study sites is about 0.482 m, this implies that ALT will increase by 0.074 to 0.217 m (15% and 45%) in 2080s. This will have substantial impacts on Arctic infrastructure. The projected settlement Iset (cm) of 1 to 7 cm will also impact the infrastructure, especially by differential settlement due to the high spatial variability of ALT and soil moisture, given at local scale the actual thawing will partly depend on thaw sensitivity of the material and potential thaw strain, which could vary widely from location to location.

期刊论文 2025-10-01 DOI: 10.1061/JHYEFF.HEENG-6485 ISSN: 1084-0699

Small modular reactors (SMRs) are an alternative for clean energy solutions in Canada's remote northern communities, owing to their safety, flexibility, and reduced capital requirements. Currently, these communities are heavily reliant on fossil fuels, and the transition to cleaner energy sources, such as SMRs, becomes imperative for Canada to achieve its ambitious net-zero emissions target by 2050. However, applying SMR technology in permafrost regions affected by climate change presents unique challenges. The degradation of permafrost can lead to significant deformations and settlements, which can result in increased maintenance expenses and reduced structural resilience of SMR infrastructure. In this paper, we studied the combined effect of climate nonstationarity in terms of ground surface temperature and heat dissipation from SMR reactor cores for the first time in two distinct locations in Canada's North: Salluit in Quebec and Inuvik in the Northwest Territories. It was shown that these combined effects can make significant changes to the ground thermal conditions within a radius of 15-20 m around the reactor core. The change in the ground thermal conditions poses a threat to the integrity of the permafrost table. The implementation of mitigation strategies is imperative to maintain the structural integrity of the nuclear infrastructure in permafrost regions. The thermal modeling presented in this study paves the way for the development of advanced coupled thermo-hydromechanical models to examine the impact of SMRs and climate nonstationarity on permafrost degradation.

期刊论文 2025-09-01 DOI: 10.1061/JCRGEI.CRENG-804 ISSN: 0887-381X

Ongoing climate change is critically endangering cold regions, with the Arctic warming at nearly four times the global average. This rapid warming is not only accelerating the irreversible thawing of permafrost but is also reshaping the region's topography, vegetation, hydrology, infrastructure integrity, and carbon exchange. The destabilization of the ground through thaw of ice-rich permafrost, known as thermokarst, is increasing to mass-wasting events such as active-layer detachment failures (ALDs), shallow landslides that are becoming increasingly common in the Arctic. In light of these alarming developments, our study employs the Maxent statistical model to analyze ALD distribution, develop a susceptibility map for Alaska and Northwest Territories, Canada, in the current climate, and assess the potential impact to infrastructure. We identified high-susceptibility zones across critical regions, including the Brooks Range, Franklin Mountains, and West Crazy Mountains in Alaska, as well as the Dawson City and Mackenzie River areas in Canada. Particularly concerning is the vulnerability of linear infrastructure: 878 km of roads, 167 km of the Trans-Alaska pipeline, and 140 km of the Norman Wells pipeline are situated in areas of high to very high susceptibility to ALDs. These results highlight the urgent need for proactive strategies and infrastructure planning to deal with the growing threats from permafrost thaw and its wide-ranging effects.

期刊论文 2025-08-14 DOI: 10.1007/s10346-025-02603-x ISSN: 1612-510X

Small organic compounds (SOCs) are widespread environmental pollutants that pose a significant threat to ecosystem health and human well-being. In this study, the FrmA gene from Escherichia coli was overexpressed alone or in combination with FrmB in Arabidopsis thaliana and their resistance to multiple SOCs was investigated. The transgenic plants exhibited varying degrees of increased tolerance to methanol, formic acid, toluene, and phenol, extending beyond the known role of FrmA in formaldehyde metabolism. Biochemical and histochemical analyses showed reduced oxidative damage, especially in the FrmA/BOE lines, as evidenced by lower malondialdehyde (MDA), H2O2 and O-2(center dot-) levels, indicating improved scavenging of reactive oxygen species (ROS). SOC treatment led to significantly higher levels of glutathione (GSH) and, to a lesser extent, ascorbic acid (AsA) in the transgenic plants than in the wild-types. After methanol exposure, GSH levels increased by 95 % and 72 % in the FrmA/BOE and FrmAOE plants, respectively, while showing no significant increase in the wild-type plants. The transgenic plants also maintained higher GSH:GSSG and AsA:DHA ratios, exhibited upregulated glutathione reductase (GR) and dehydroascorbate reductase (DHAR) activities, and correspondingly increased gene expression. In addition, the photosynthetic parameters of the transgenic plants were less affected by SOC stress, which represents a significant photosynthetic advantage. These results emphasize the potential of genetically engineered plants for phytoremediation and crop improvement, as they exhibit increased tolerance to multiple hazardous SOCs. This research lays the foundation for sustainable approaches to combat pollution and improve plant resilience in the face of escalating environmental problems.

期刊论文 2025-08-05 DOI: 10.1016/j.jhazmat.2025.138352 ISSN: 0304-3894

Ginger is a significant ethnobotanical and pharmacological crop consisting of potential bioactive constituents responsible for their nutraceutical value, they can have anti-inflammatory, antiobesity, antidiabetic, antinausea, antimicrobial, pain alleviation, antitumor, antioxidant and protective effects on respiratory disease, and agerelated disease. Ginger possesses a substantial value, but its production and general quality are greatly harmed by various biotic and abiotic stressors, to which it is highly susceptible. Fungi are the most damaging disease-causing agents, one of the devastating fungal pathogens in ginger is Fusarium spp., a soil and seed-borne pathogen resulting in poor production, poor quality, and decreased economic returns to the farmers. It infects ginger in every stage of development and each plant part even during post-harvest storage. This review emphasizes a comprehensive understanding of the nutraceutical value of ginger compounds, and Fusarium disease in ginger with its pathogenicity. Moreover, this review elaborates on an improvement of ginger yield by the management of the Fusarium pathogen through the biological and biotechnological approach.

期刊论文 2025-08-01 DOI: 10.1016/j.micpath.2025.107597 ISSN: 0882-4010

The flexible joints and segmental lining serve as effective seismic measures for tunnel in high-intensity seismic area. However, the tunnel axial deformation at flexible joints has not been fully incorporated into analytical models. This study presents a novel mechanical model for flexible joints that considers tension (compression)shear-rotation deformations, replacing the traditional shear-rotation springs model. An improved semi-analytical solution has been developed for the longitudinal response of a tunnel featuring a three-way flexible joint mechanical model subjected to fault movement. The nonlinear elastic-plastic foundation spring, the soil-lining tangential interaction, and the axial force of tunnel lining have been considered to improve the applicability and precision of proposed method. The proposed solution is compared with existing models, such as short beams connected by shear and rotation springs, by examining the predictions against numerical simulations. The results indicate that the predictions of the proposed model align much more closely with the outcomes of the numerical simulations than those of the existing models. For the working conditions selected in 4, neglecting the tension-compression deformation at flexible joints an 81.8% error in the peak axial force of the tunnel and a 20.2% error in the peak bending moment. The reason is that ignoring the axial deformation of these joints results in a larger calculated axial force on the lining, which subsequently leads to increased bending moment and shear force. Finally, a parameter sensitivity analysis is conducted to investigate the effect of various factors, including flexible joint stiffness, segmental lining length, and the length of the tunnel fortification zone.

期刊论文 2025-08-01 DOI: 10.1016/j.tust.2025.106590 ISSN: 0886-7798

This manuscript presents a comprehensive presentation of ground temperature data collected at 16 nodes of the 121 of the Crater Lake Circumpolar Active Layer Monitoring (CALM) site on Deception Island, Antarctica, from 2008 to early 2022. Each one of the 16 shallow boreholes has been equipped with miniature temperature loggers, providing valuable insights into the thermal regime of the ground at a depth of 50 cm, which corresponds to the mean depth of the top of the permafrost table as observed by annual mechanical probing in the CALM site. Despite a 9-month long gap in data collection during 2017 due to persistent snow cover, the time series remains largely intact, with annual measurements taken every 3 h. The manuscript details the methodologies employed for data collection, including the use of iButton loggers, and outlines the challenges faced in retrieving and processing the data in the harsh Antarctic environment. The cleaned dataset, which consolidates data from various nodes while removing erroneous records, is made freely accessible to the scientific community without any additional processing of the data such as offset corrections or gaps interpolation. This resource is expected to facilitate further research into the thermal dynamics of the active layer and permafrost and its implications for climate change since both are influenced by external factors such as snow cover, air temperature and others. Overall, the presented dataset contributes to the limited body of knowledge regarding Antarctic permafrost and provides a foundation for future investigations into the effects of climate change on frozen ground dynamics. The dataset serves as a vital tool for researchers aiming to model ground thermal behaviour and assess the impacts of environmental changes in polar regions.

期刊论文 2025-07-21 DOI: 10.1002/gdj3.70019 ISSN: 2049-6060

Southern boundary areas of high-latitude permafrost regions may represent the future permafrost temperature regimes; therefore, understanding the carbon stocks and their stability in these systems can shed light on the permafrost carbon cycle under a warming climate. In this study, we sampled soils at three sites representing three differing land covers (forest swamp, dry forest, and shrub swamp) located in the southern boundary area of a high-latitude permafrost region and investigated their carbon fractions and the relationships of these fractions with soil physicochemical parameters in the active and permafrost layers. The results show that the proportion of active carbon is higher in permafrost than in the active layer under forest swamp and dry forest, implying that carbon pools in the permafrost are more decomposable. However, in shrub swamp, the active carbon components in the permafrost layer are lower than in the active layer. Soil pH and water content are the most significant factors associated with soil organic carbon concentration both in the active layers and in the permafrost layers. Our results suggest that, although soil organic carbon concentrations largely decrease with depth, the proportion of the forest swamp, dry forest labile carbon is higher in the permafrost layer than in the active layer and that the vertical distribution of labile carbon proportions is related to land covers.

期刊论文 2025-07-15 DOI: 10.1002/ppp.70002 ISSN: 1045-6740
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