Heliotropium L. genus belongs to the Boraginaceae family and is represented by approximately 250 species found in the temperate warm regions of the world, and there are 15 species of these species recorded in Turkiye. Heliotropium hirsutissimum Grauer grows in Bulgaria, Greece, N. Africa, Syria, and Turkiye. There is no record showing that H. hirsutissimum is a heat-tolerant plant. However, in our field studies, it was observed that H. hirsutissimum, which is also distributed in Hisaralan Thermal Springs of Sindirgi-Balikesir, Turkiye, grows in the thermal area with extremely high soil temperature (57.6 degrees C (similar to 60 degrees C)). It was thought that it would be useful to investigate the tolerance mechanism of the H. hirsutissimum plant to extremely high temperatures. For this purpose, the plant seeds were obtained from a geothermal area in the thermal spring. Growing plants were exposed to 20, 40, 60, and 80 +/- 5 degrees C soil temperature gradually for 15 days under laboratory conditions. We measured the effect of high soil temperature on some morphological changes, relative water content, thiobarbituric acid reactive substances, cell membrane stability, and hydrogen peroxide analysis to determine stress levels on leaves and roots. Changes in osmolyte compounds, some antioxidant enzyme activities, ascorbate content, and chlorophyll fluorescence and photosynthetic gas exchange parameters were also determined. As a result of the study carried out to determine the stress level, it was observed that there was not much change and it was understood that the plant was tolerant to high soil temperature. In addition, there was a general increase in osmolytes accumulation, antioxidant enzyme activities, and ascorbate level. There was no significant difference in photosynthetic gas exchange and chlorophyll fluorescence parameters of plants grown at different soil temperatures. The high temperature did not negatively impact the photosynthetic yield of H. hirsutissimum because this plant was found to enhance its antioxidant capacity. The increase in antioxidant activity helped reduce oxidative damage and protect the photosynthetic mechanism under high temperature conditions, while the significant increase in the osmolyte level helped maintain the water status and cell membrane integrity of plants, thus enabling them to effectively withstand high soil temperatures.

The accumulation or landfill of lithium slag will contaminate the surrounding soil and water quality with residual sulfides and harmful elements, causing serious environmental hazards. This study aims to use Lithium slag (LS) as a sustainable alternative for silica flour (SF) in high-temperature cementing and examines the effects of this substitution on the microstructural and mechanical properties of cement pastes. The results show that an appropriate amount of LS can reduce the permeability of oil well cement and increase its high temperature compressive strength. Compared with pure paste (RS), the compressive strength of the sample replaced by 30 % LS increased by 87.8 % and the permeability decreased by 57.1 % after 28 days of high temperature curing. From the phase point of view, the samples supplemented with LS can form Xonotlite and Katoite with dense structure and high temperature stability. These hydration products can reduce the matrix porosity and permeability, increase the matrix density, and effectively improve the compressive strength of the cement pastes. In addition, the environmental effect analysis showed that the leaching toxicity and radioactivity of the sample did not exceed the standard requirements. This study provides a new direction for the sustainable utilization of LS resources, which not only combats the environmental pollution caused by LS accumulation, but also reduces the cost of cementing materials.

Earthen sites of substantial significance have experienced considerable degradation. Chemical stabilization is a commonly used restoration technique, and temperature effects are a critical factor for this degradation, particularly for outdoor sites. However, significant gaps exist in research on the threats posed to stabilization materials by elevated temperatures. Therefore, this study investigates polyvinyl alcohol (PVA) as a representative organic stabilizer to examine the effects of temperature variations from 20 degrees C to 400 degrees C on mechanical properties and microstructure of PVA-stabilized soil. A combination of macro- and micro-scale characterization techniques, alongside theoretical modelling, is employed. The results show that constitutive models inspired by concrete effectively characterize the stress-strain behavior of PVA-stabilized soil under high-temperature conditions. Unconfined compressive strength of PVA-stabilized soil significantly decreases from 0.90-2.25 to 0.17-0.40 MPa as the temperature increases from 200 degrees C to 300 degrees C, which is attributed to structural changes of soil induced by thermal decomposition of PVA. The thermal degradation of PVA can generate harmful gases and cause a significant colour change. Therefore, organic materials like PVA are suitable for the restoration of earthen sites in non-fire-risk areas. However, caution is necessary when applying these materials in earthen sites at risk of fire hazards, especially those with vegetation cover.

This study investigates the effect of different in situ conditions like flaw infill, heat-treatment temperatures, and sample porosities on the anisotropic compressive response of jointed samples with an impersistent flaw. Jointed samples of different porosities are prepared by mixing Plaster of Paris (POP) with different water contents, i.e. 60% (i.e. for lower porosity) and 80% (i.e. for higher porosity). These samples are grouted with different infill materials, i.e. un-grouted, cement and sand-cement (3:1)-bioconcrete (SCB) mix and subsequently subjected to different temperatures, i.e. 100 degrees C, 200 degrees C and 300 degrees C. The results reveal the distinct stages in the stress-strain responses of samples characterized by initial micro-cracks closure, elastic transition, and non-linear response till peak followed by a post-peak behaviour. The un-grouted samples exhibit their lowest strength at 30 degrees joint orientation. The ratios of maximum to minimum strength are 3.11 and 3.22 with varying joint orientations for lower and higher porosity samples, respectively. Strengths of cement and SCB mix grouted samples are increased for all joint orientations ranging between 16.13%-69.83% and 18.04%-73% at low porosity and 22%-48.66% and 27.77%-51.57% at high porosity, respectively as compared to the un-grouted samples. However, the strength of the grouted samples is decreased by 66.94%-75.47% and 77.17%-81.05% at lower porosity, and 79.37%-82.86% and 81.29%-95.55% at higher porosity for cement and for SCB grouts with an increase in the heating temperature from 30 degrees C to 300 degrees C, respectively. These observations could be due to the suppression of favourable crack initiation locations, i.e. flaw tips along the samples due to the filling of the crack by grouting and generation of thermal cracks with temperature. The mechanism of strength behaviour is elucidated in detail based on fracture propagation analysis and the anisotropic response of with or, without grouted samples. (c) 2025 Institute of Rock and Soil Mechanics, Chinese Academy of Sciences. 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/).

Climate change and its impact on agricultural production due to the occurrence of extreme weather events appear to be more imminent and severe than ever, presenting a global challenge that necessitates collective efforts to mitigate its effects.There have been many practical and modelling studies so far to estimate the extent of climate change and possible damages on agricultural production, suggesting that water availability may decrease by 50% and agricultural productivity between 10 and 30% in the coming years ahead. Though there have been many studies to estimate the possible level of damage by the climate change on the production of many agricultural crops, no study has been conducted on the greenhouse tomato production. Therefore, this study was conducted to discover the effects of extreme high temperatures during the 2022-2023 growing season on the high-tech Turkish tomato greenhouse industry through a survey. The results showed that all greenhouses lost yield, ranging from 6 to 53%, with an average of 12.5%. Survey data revealed that irrigation and fog system water consumption increased by 29.32% and 31.42%, respectively, while fertilizer and electricity consumption rose by 23.66% and 19%. Some 76.5% of the growers declared difficulty in climate control, 11.7% reported tomato cluster losses with no information on yield loss, 9% experienced yield losses despite no cluster losses, and 61.7% observed a decline in tomato quality, leading to reduced sales prices. Considering these findings, it is recommended that greenhouses must adopt advanced climate control technologies, expand fog system capacities, and integrate renewable energy sources to enhance resilience against climate-induced challenges. Additionally, improving water-use efficiency, optimizing cooling strategies, using new and climate-resistant varieties and adjusting cropping seasons could help mitigate yield losses due to extreme temperatures. The study results offer extremely valuable insights into greenhouse production for researchers, technology developers, and policymakers for the mitigation of climate change effects and the development of more sustainable production systems.

The impact of temperature on soil dynamics has long been a topic of widespread interest. However, the effects of high-temperature environments caused by phenomena such as wildfires and tunnel fires on soil remain poorly understood. This study, using purple soil from Chongqing, China as a representative, investigates the effects of high-temperature conditions on the mechanical properties and microstructure of this soil type. The results show that unconfined compression strength, deformation modulus, and strain energy density at peak of purple soil tend to increase with the increase of the treatment temperature from 20 degrees C to 1000 degrees C. This enhancement becomes pronounced when the temperature exceeds 600 degrees C. The physical and chemical changes are employed to elucidate the evolution of mechanical properties, and significant reinforcement effect primarily attributed to the 'welding action' of clay minerals. The variation in pore size distribution becomes significant when the treatment temperature approaches 800-1000 degrees C, and soil samples become vesicular structure at 1000 degrees C. These transformations depend on the decomposition of CaCO3, as well as the redistribution and confining effects of melted illite. Therefore, following high-temperature treatment, purple soil exhibits the capacity to alleviate environmental degradation from the perspective of mechanical properties. Purple soil exposed to temperatures between 800 and 1000 degrees C exhibits properties akin to those of clay bricks, making it a viable material for construction purposes. This research holds substantial significance for environmental engineering, geological engineering, and the development of construction materials following thermal treatment.

The roughness of the fracture surface directly affects the strength, deformation, and permeability of the surrounding rock in deep underground engineering. Understanding the effect of high temperature and thermal cycle on the fracture surface roughness plays an important role in estimating the damage degree and stability of deep rock mass. In this paper, the variations of fracture surface roughness of granite after different heating and thermal cycles were investigated using the joint roughness coefficient method (JRC), three-dimensional (3D) roughness parameters, and fractal dimension (D), and the mechanism of damage and deterioration of granite were revealed. The experimental results show an increase in the roughness of the granite fracture surface as temperature and cycle number were incremented. The variations of JRC, height parameter, inclination parameter and area parameter with the temperature conformed to the Boltzmann's functional distribution, while the D decreased linearly as the temperature increased. Besides, the anisotropy index (I-p) of the granite fracture surface increased as the temperature increased, and the larger parameter values of roughness characterization at different temperatures were attained mainly in directions of 20 degrees-40 degrees, 60 degrees-100 degrees and 140 degrees-160 degrees. The fracture aperture of granite after fracture followed the Gauss distribution and the average aperture increased with increasing temperature, which increased from 0.665 mm at 25 degrees C to 1.058 mm at 800 degrees C. High temperature caused an uneven thermal expansion, water evaporation, and oxidation of minerals within the granite, which promoted the growth and expansion of microfractures, and reduced interparticle bonding strength. In particular, the damage was exacerbated by the expansion and cracking of the quartz phase transition after T > 500 degrees C. Thermal cycles contributed to the accumulation of this damage and further weakened the interparticle bonding forces, resulting in a significant increase in the roughness, anisotropy, and aperture of the fracture surface after five cycles. (c) 2025 Institute of Rock and Soil Mechanics, Chinese Academy of Sciences. 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/).

High-temperature thermal desorption is effective for remediating organic-contaminated sites, but its damage to soil functions and high energy consumption raise concerns. In this work, the variation of fertility indicators of two soils with thermal treatment temperature was investigated experimentally. To overcome the difficulties in measuring soil thermophysical properties under sealing and high-temperature conditions, two apparatus matching with the Hot Disk device were established and by which massive data were measured. The results show that, as temperature rises up to 500 degrees C, the combustion and decomposition of organic components and soil minerals gradually enhance, leading to a decrease in most fertility indicators, but an increase in grain size and pH. Available phosphorus and exchangeable potassium decrease with temperature rise first, but increase over 400 degrees C. Soil thermal conductivity and specific heat are positively correlated with temperature and water content. Water diffusion will intensify over 40 similar to 60 degrees C, leading to an intense increase in soil thermal conductivity. The results are expected to provide data basis and theoretical guidance for the comprehensive consideration of remediation effects, land reuse, and energy consumption in practical applications of thermal desorption remediation.

To achieve the repeatability of aerospace thermal components, C/TaC-SiC composites were fabricated. Cycle ablation and bending tests were carried out. After 3 x 60 s of ablation beyond 2100 degrees C, the mechanical property retention rate was 80.9%. Interestingly, a reaction similar to ouroboros ring, in which the cyclic reactions of TaC being oxidized to Ta2O5 and Ta2O5 being reduced to TaC, occurred in the central ablation region of C/TaC-SiC composites. On the one hand, the continuous generation of TaC could prevent liquid state Ta2O5 from being blown off central ablation region, playing a similar role in water and soil conservation. On the other hand, liquid Ta2O5 covered the surface of C/TaC-SiC composites during ablation process, contributing to block the inward permeation of oxidized gases. In addition, novel Grotto structures were detected in the transitional ablation region of C/TaC-SiC composites. The formation reason of the Grotto structure has also been discussed.

Context or problem: As global temperatures steadily increase, the frequent occurrence of extreme hightemperature events has significantly hampered peanut (Arachis hypogaea L.) production in low-latitude regions. Objective or research question: Previously, 24-epibrassinolide (EBR) was identified as a substance capable of mitigating abiotic stress damage in plants. However, it remains unclear whether and by what mechanisms EBR can diminish the yield loss caused by heat stress in peanuts. Methods: During the flowering phase, two distinct peanut cultivars, Qinghua7 (heat-resistant type) and Shanhua101 (heat-sensitive type) were exposed to a 10-day heat stress treatment (+4.2 degree celsius). EBR or water was sprayed on the 1st, 3rd, and 5th days of heating, and water-sprayed natural peanuts was used as control, to assess the effect of EBR on antioxidant capacity, photosynthetic performance, and yield in heat-stressed peanuts. Results: EBR application increased activities of superoxide dismutase, peroxidase, catalase, and ascorbate peroxidase in heat-stressed peanut leaves. Simultaneously, EBR decreased hydrogen peroxide and superoxide anion production, along with a reduction in malondialdehyde content. Additionally, EBR notably alleviated the oxidation damage to chloroplast membranes and grana lamella under heat stress. Thus, an increase in maximum photochemical efficiency, comprehensive performance index, rubisco activity, net photosynthetic rate, and biomass accumulation was observed in heat-stress peanuts. Synergistic enhancement provided by EBR on antioxidant capacity and photosynthetic performance resulted in improved plant growth, kernel weight, and effective pods per plant, led to a reduction in yield loss for heat-stressed cultivars Qinghua7 and Shanhua101 by 26.92 % and 55.18 %, respectively. Conclusions: The application of EBR enhanced the antioxidant capacity of peanut leaves. This, in turn, mitigated oxidative damage to chloroplast membranes, resulting in improved photosynthetic performance. Ultimately, this intervention led to a reduction in yield loss for heat-stressed peanuts, achieved through an increase in kernel weight. Implications or significance: The foliar spraying of EBR holds significant promise in crop production, offering a broad application prospect. This practice is beneficial for enhancing the heat resistance of peanuts and potentially other field crops, equipping them to better withstand the increasingly severe climate challenges anticipated in the future.