In sensitive ecosystems of the Arctic, even slight disruptions may produce serious damage. Therefore, the extent of contamination in such zones should be evaluated. A comparison was made between concentrations of metals in Sanionia uncinata in three areas of the European Arctic: (1) the vicinity of the Polish Polar Station in the SW part of Spitsbergen on Wedel Jarlsberg Land, (2) Longyearbyen (Spitsbergen) influenced by local sources of pollution and (3) Iceland relatively free from local pollution. The tested hypothesis was that S. uncinata from Iceland contains significantly lower concentrations of metals than the same moss from Spitsbergen. The maximum concentrations of metals in the examined moss from Longyearbyen reached values for Cr and Mn higher than those known as harmful for plants and for Ni and Zn values within the harmful ranges with no visible harmful effects. S. uncinata from Iceland contained significantly lower concentrations of Cd, Mn, Pb compared to this species from Spitsbergen. S. uncinata seems to be a useful indicator for metal fallout in the European Arctic. This study presents the effects of local sources of contamination on metal levels in S. uncinata from Longyearbyen, Wedel Jarlsberg Land and Iceland as well as verification of S. uncinata as a suitable bioindicator in this Arctic area. The benefit of the study is a to better understanding contamination problems of Arctic habitats.

The soilbags reinforcement has been widely used for soft soil foundation improvement due to its high compressive strength and deformation modulus considering the time limit of many projects and the characteristics of the reclaimed soil. However, despite the strength and deformation properties of soilbags reinforcement, the drainage characteristics of soilbags reinforcement is a crucial factor that creates a large challenge to foundation improvement for soft soil. Thus, this study developed a four-staged surcharge preloading on soilbags-reinforced soft soil foundation and focused on its drainage consolidation effectiveness. The contrasting laboratory tests were performed in four identical experimental boxes with clayey soil from the Nanjing, China. Four-staged preloading were applied on the soilbags-reinforced testing model, respectively, the data of the settlement and water discharge during the test are monitored, and after the tests, the water content and shear strength at different positions are measured. And three contrasting tests considering the possible drainage channels of soilbags reinforcement were also conducted. The results show that the consolidation effect is achieved with the soilbags reinforcement in terms of the settlement, pore water pressure, water content and shear strength after consolidation.

A novel slope stabilization technique was recently developed incorporating screw piles with vegetated flapped soilbags. These screw piles are subjected to lateral stress from soil slope and their deformation can be difficult to quantify, given the fluctuating pore-water pressure and heterogeneous soil conditions. This study proposes the use of in-situ spectral analysis of surface waves (SASW) test to estimate the small-strain soil stiffness which can then be factored to calculate the lateral deformation of the pile in finite element modelling based on prescribed pore-water pressure change. A case of bioengineered slope in Kanchanaburi province, Western Thailand was studied, involving field monitoring of pile head tilt, pore-water pressure, suction, and soil moisture over one year. The findings revealed pile head tilt of up to 0.2 degrees in response to rainfall and rise in pore-water pressure and soil moisture over one year period. A series of finite element modelling were performed using factored shear moduli from in-situ SASW test and the monitored pore-water pressure variation to reproduce the amount of pile head tilting as observed in the field during one year. It was revealed that by assuming operational shear modulus ranging between 0.0075 and 0.01 times small-strain soil stiffness, a satisfactory agreement was obtained between field measurement and analysis of pile movement. This findings provides a basis for further studies on performance of bioengineered slope utilizing screw piles. (c) 2025 Japanese Geotechnical Society. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http:// creativecommons.org/licenses/by-nc-nd/4.0/).

The restraining effect of soilbags inhibits soil dilatancy, enhancing the strength and stiffness of the wrapped soil. As a permanent slope protection structure (SSPS), the application of counterpressure enhances stability by improving slope surface stiffness and limiting deformation. While reinforced slopes have been extensively studied, mechanistic investigations into the stability and failure processes of SSPS remain limited. This study numerically investigated the macro-meso mechanisms of SSPS instability using the discrete element method. Macroscopically, rainfall infiltration increases water absorption, resulting in longitudinal settlement, deformation, and eventual instability. With a friction coefficient of 0.5, the lower soilbags resist sliding forces until the front soilbags are damaged. Inadequate sufficient friction causes the front soilbags to be displaced outward, leading to structural collapse as the lower soilbags bear the additional load. Microscopically, geosynthetic wrapping restrains soil dilatancy, promoting tighter particle arrangements and secondary reinforcement through soilbag expansion. During instability, primary contact forces concentrate on longitudinal settlement, vertical back pressure, and downslope sliding, with force chain evolution revealing slip band formation. Soilbags facilitate coordinated particle deformation and stress distribution, transitioning from anisotropic to isotropic states as instability progresses. These findings enhance the understanding of SSPS instability mechanisms, providing guidance for more reliable design and construction practices.

Two earthquakes, Mw = 7.8 Kahramanmaras,-Pazarcik, and Mw = 7.6 Elbistan, occurred on February 6, 2023, approximately 9 h apart. These earthquakes caused devastating effects in a total of 11 nearby cities on the east side of T & uuml;rkiye (Adana, Adiyaman, Diyarbakir, Elazig, Gaziantep, Hatay, Kahramanmaras,, Kilis, Malatya, Osmaniye, and S,anliurfa) and the north side of Syria. These earthquakes provided an outstanding prospect to observe the effects of liquefaction in silty sand and liquefaction-like behavior in clays (cyclic softening) on the stability of structures. This paper specifically presents the post-earthquake reconnaissance at three sites and evaluations of four buildings within these sites in Adiyaman Province, Golbas, i District. First, important role of post-earthquake piezocone penetration test (CPTu) in characterizing the subsurface conditions was presented. Then, the effect of soil liquefaction and cyclic softening on the performance of four buildings during the earthquakes was evaluated. These structures represent the typical new reinforced concrete buildings in T & uuml;rkiye with 3 to 6-story, situated on shallow (raft) foundations, and demonstrated diverse structural performances from full resilience to moderate and extensive damage during the aforementioned earthquakes. Based on the interim findings from these sites, the potential factors that caused moderate to severe damage to buildings were inspected, and preliminary-immediate insights were presented on the relationship between structural design, soil properties, and the performance of buildings with shallow foundations.

Environmental changes, such as climate warming and higher herbivory pressure, are altering the carbon balance of Arctic ecosystems; yet, how these drivers modify the carbon balance among different habitats remains uncertain. This hampers our ability to predict changes in the carbon sink strength of tundra ecosystems. We investigated how spring goose grubbing and summer warming-two key environmental-change drivers in the Arctic-alter CO2 fluxes in three tundra habitats varying in soil moisture and plant-community composition. In a full-factorial experiment in high-Arctic Svalbard, we simulated grubbing and warming over two years and determined summer net ecosystem exchange (NEE) alongside its components: gross ecosystem productivity (GEP) and ecosystem respiration (ER). After two years, we found net CO2 uptake to be suppressed by both drivers depending on habitat. CO2 uptake was reduced by warming in mesic habitats, by warming and grubbing in moist habitats, and by grubbing in wet habitats. In mesic habitats, warming stimulated ER (+75%) more than GEP (+30%), leading to a 7.5-fold increase in their CO2 source strength. In moist habitats, grubbing decreased GEP and ER by similar to 55%, while warming increased them by similar to 35%, with no changes in summer-long NEE. Nevertheless, grubbing offset peak summer CO2 uptake and warming led to a twofold increase in late summer CO2 source strength. In wet habitats, grubbing reduced GEP (-40%) more than ER (-30%), weakening their CO2 sink strength by 70%. One-year CO2-flux responses were similar to two-year responses, and the effect of simulated grubbing was consistent with that of natural grubbing. CO2-flux rates were positively related to aboveground net primary productivity and temperature. Net ecosystem CO2 uptake started occurring above similar to 70% soil moisture content, primarily due to a decline in ER. Herein, we reveal that key environmental-change drivers-goose grubbing by decreasing GEP more than ER and warming by enhancing ER more than GEP-consistently suppress net tundra CO2 uptake, although their relative strength differs among habitats. By identifying how and where grubbing and higher temperatures alter CO2 fluxes across the heterogeneous Arctic landscape, our results have implications for predicting the tundra carbon balance under increasing numbers of geese in a warmer Arctic.

We review the progress of research on permafrost and periglacial dynamics over the last two decades and explore future periglacial landscapes in Svalbard, High Arctic. This area has been subjected to rapid air and ground warming at a rate of 0.10.2 degrees C yr-1, as well as simultaneous thawing of the top layer of permafrost at a rate of about 1 cm yr-1 over the last two decades. Periglacial features studied include ice-wedge polygons, mudboils, sorted patterned ground, pingos, solifluction lobes, active-layer detachment slides, and rock glaciers. These landforms are concentrated within narrow alluvial plains and valley-side slopes but separated by geomorphological specifics and ground materials. Decadal-scale monitoring highlights climatic control of the morphology and dynamics of three landforms & horbar;ice-wedge polygons, mudboils, and rock glaciers & horbar;and the impact of long-term warming on their dynamics. Despite the location close to the southern limit of continuous permafrost, multiple cold spells in mid-winter activate thermal contraction cracking, which permits the growth of ice wedges. If such cold spells continue under a warmer climate, ice wedge could still grow below the deepening active layer. In a mudboil-small polygon landscape, seasonal frost heaving (or thaw settlement) of the central mound is coupled with closing (or opening) of the marginal crack. This movement would be maintained under a warmer climate and at a deeper active layer if the active layer is kept very humid. Although the contemporary cold climate is generally unfavorable for the growth of well-developed rock glaciers in Svalbard, slow permafrost creep at a rate of a few centimeters per year produces basal bulging of the valley-side talus slopes. The warming trend in the last decade has led to a steady acceleration of the movement. Further warming in the near future is expected to develop longer valley-side rock glaciers.

To explore an effective method for deformation monitoring and behavior prediction of expansive soil slope, field tests are conducted for a flexible slope protection scheme with soilbags that has been implemented in an expansive highway soil slope. A new monitoring system, i.e., the universal Beidou deformation monitoring system, is developed to overcome the limitations of traditional Global Navigation Satellite System (GNSS) software and hardware, simplify the hardware structure and realize the power sharing mode; furthermore, this system can create and upload a large amount of monitored data to a cloud platform to enable real-time calculation. Compared with traditional GNSS, the volume of equipment required is reduced by approximately 75%, and the cost is reduced by approximately 80%. Secondly, a multilevel safety early-warning evaluation system is constructed by integrating the monitoring results of the universal Beidou deformation monitoring system, bag damage states, rainfall conditions, and slope fissure development; additionally, a deformation early-warning mechanism of flexible support of soilbags was established. Finally, the deformation and collapse of flexible supports of soilbags can be successfully predicted in the field. This research on flexible support of soilbags provides new ideas and methods of deformation monitoring, safety evaluation, and early warning for expansive soil slopes.

The constraining effect of soilbags inhibits soil dilatancy, enhancing the strength and stiffness of the wrapped soil, and resulting in a considerable increase in bearing capacity. This study numerically investigated the macromeso geotextile failure behavior, stress state, fabric anisotropies of wrapped soil and interlocking reinforcement mechanisms of three-layer soilbags under unconfined compression using the three-dimensional discrete element method (DEM). Macroscopically, the failure modes of wrapping geosynthetic depended on the friction between soilbags. With zero friction, failure initiated at the edges of the wrapping geosynthetic; whereas with a friction coefficient of 0.5, failure began in the middle and extended to the edges, showing a progressive failure pattern. Microscopically, the reinforcement of soilbag changed the contact pattern of the particle system from peanut-like to uniformly distributed ellipse. The load transfer to the boundaries caused the occurrence of wrapped soil expansion and geotextile rupture. Additionally, geosynthetic wrapping created an interlocking effect with the surrounding soils, forming a positive feedback to reinforce the wrapped soil before geotextile failure. New understanding on failure modes, stress states, interlocking effect and fabric anisotropies provides a solid foundation for designing reliable and stable soilbag geotechnical permanent protective structures.

The earthquakes in Pazarc & imath;k (Mw 7.7) and Elbistan (Mw 7.6), occurring along the East Anatolian Fault Zone (EAFZ) on February 6, 2023, caused significant damage and destruction to the built environment within the affected area. In this study, the preliminary site investigations were conducted in the G & ouml;lba & scedil;& imath; district, where the impacts of both earthquakes were severely felt, offering scientifically valuable information regarding the soil damage. Comprehensive liquefaction analyses were performed using the geotechnical laboratory test data on soil specimens collected from the G & ouml;lba & scedil;& imath; district. These analyses confirmed the liquefaction-induced ground failures observed immediately after the two earthquakes. Furthermore, microzonation data collected in the G & ouml;lba & scedil;& imath; district were consolidated, and seismic site response analyses were conducted. Simulations showed that local soils in the region could amplify seismic waves by a factor of two. Utilizing the calculated Peak Ground Acceleration (PGA) and amplification factors, GIS-based distribution maps of the entire area were developed. These maps serve as practical resources for practitioners and local planners, aiding in spatial settlement decisions and urban transformation planning. They contribute significantly to enhancing the understanding of earthquake hazards in the region.