The Himalayan glacier valleys are encountering escalating environmental challenges. One of the contributing factors is thought to be the rising amounts of light-absorbing carbonaceous aerosols, particularly brown carbon (BrC) and black carbon (BC), that are reaching glacier valleys. The present study examines the optical and radiative characteristics of BC at Bhojbasa, near Gaumukh (similar to 3800amsl). Real-time in-situ BC data, optical characteristics, radiative forcing, heating rate, several meteorological parameters, and BC transport pathways to this high-altitude site are investigated. The daily mean concentration of equivalent black carbon (eBC) was 0.28 +/- 0.21 mu g/m(3) over the research period, and the eBC from fossil fuel (BCFF) is dominant with 78 % with a daily mean of 0.22 +/- 0.19 mu g/m(3)(,) and eBC from biomass burning (BCBB) is 22 % with a daily mean of 0.06 +/- 0.08 mu g/m(3). Meteorological data, Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) imaging, and backward air-mass trajectory analysis demonstrate the presence of BC particles and their plausible transit pathways from multiple source locations to the pristine Gangotri Glacier Valley. The estimated daily mean BC radiative forcing values are +6.71 +/- 1.80 W/m(2) in the atmosphere, +1.87 +/- 1.16 W/m(2) at the top of the atmosphere, and -4.84 +/- 1.01 W/m(2) at the surface with a corresponding atmospheric heating rate of 0.19 +/- 0.05 K/day. These findings highlight the critical role of ground-based measurements in monitoring the fluctuations of BC over such varied Himalayan terrain, as they offer important information on the localized trends and effects. Long-term measurements of glacier valleys are essential for a comprehensive evaluation of the impact of BC particles on Himalayan ecology and climate.
Light-absorbing carbonaceous aerosols, comprising black carbon (BC) and brown carbon (BrC), significantly influence air quality and radiative forcing. Unlike traditional approaches that use a fixed value of absorption & Aring;ngstrom exponent (AAE), this study investigated the absorption and optical properties of carbonaceous aerosols in Beijing for both local emission and regional transport events during a wintertime pollution event by using improved AAE results that employs wavelength-dependent AAE (WDA). By calculating the difference of BC AAE at different wavelengths using Mie theory and comparing the calculated results to actual measurements from an Aethalometer (AE31), a more accurate absorption coefficient of BrC can be derived. Through the analysis of air mass sources, local emission was found dominated the pollution events during this study, accounting for 81 % of all cases, while regional transport played a minor role. Carbonaceous aerosols exhibited a continuous increasing trend during midday, which may be attributed to the re-entrainment of nighttime-accumulated carbonaceous aerosols to the surface during the early planetary boundary layer (PBL) development phase, as the mixed layer rises, combined with the variation of PBL and anthropogenic activity. At night, variations in the PBL height, in addition to anthropogenic activities, effectively contributed to surface aerosol concentrations, leading to peak surface aerosol values during local pollution episodes. The diurnal variation of AAE470/880 exhibited a decreasing trend, with a total decrease of approximately 12 %. Furthermore, the BrC fraction showed a constant diurnal variation, suggesting that the declining AAE470/880 was primarily influenced by BC, possibly due to enhanced traffic contributions.
With global warming and the intensification of human activities, frozen soils continue to melt, leading to the formation of thermokarst collapses and thermokarst lakes. The thawing of permafrost results in the microbial decomposition of large amounts of frozen organic carbon (C), releasing greenhouse gases such as carbon dioxide (CO2) and methane (CH4). However, little research has been done on the thermo-water-vapor-carbon coupling process in permafrost, and the interactions among hydrothermal transport, organic matter decomposition, and CO2 transport processes in permafrost remain unclear. We considered the decomposition and release of organic C and established a coupled thermo-water-vapor-carbon model for permafrost based on the study area located in the Beiluhe region of the Qingzang Plateau, China. The model established accurately reflected changes in permafrost temperature, moisture, and C fluxes. Dramatic changes in temperature and precipitation in the warm season led to significant soil water and heat transport, CO2 transport, and organic matter decomposition. During the cold season, however, the soil froze, which weakened organic matter decomposition and CO2 transport. The sensitivity of soil layers to changes in the external environment varied with depth. Fluctuations in energy, water, and CO2 fluxes were greater in shallow soil layers than in deeper ones. The latent heat of water-vapor and water-ice phase changes played a crucial role in regulating the temperature of frozen soil. The low content of soil organic matter in the study area resulted in a smaller influence of the decomposition heat of soil organic matter on soil temperature, compared to the high organic matter content in other soil types (such as peatlands).
Cadmium (Cd) contamination in soil threatens global food production and human health. This study investigated zinc (Zn) addition as a potential strategy to mitigate Cd stress using two barley genotypes, Dong-17 (Cd-sensitive) and WSBZ (Cd-tolerant). Hydroponically grown seedlings were treated with different Cd (0, 1.0, 10 mu M) and Zn (0, 5, 50 mu M) levels. Results showed that Zn addition effectively alleviated Cd induced growth inhibition, improving SPAD values, photosynthetic parameters, fluorescence efficiency (Fv/Fm), and biomass. Zn reduced Cd contents in roots and shoots, inhibited Cd translocation, and ameliorated Cd induced ultrastructural damage to organelles. Transcriptomic analysis revealed distinct gene expression patterns between genotypes, with WSBZ showing enhanced expression of metal transporters, antioxidant defense, and stress signaling genes. Significantly, cell wall related pathways were upregulated in WSBZ, particularly lignin biosynthesis genes (PAL, C4H, 4CL, COMT, CAD/SAD), suggesting cell wall reinforcement as a key Cd tolerance mechanism. Zn induced upregulation of ZIP family transporters and downregulation of Cd transporters (HvHMA) aligned with reduced Cd accumulation. These findings provide comprehensive insights into molecular mechanisms of Zn mediated alleviation of Cd toxicity in barley, supporting improved agronomic practices for Cd contaminated soils.
Ongoing climate change and cryospheric degradation are intensifying sediment transport in cold mountain regions, leading to elevated sediment loads that adversely impact downstream areas. However, the influence of freeze-thaw processes on daily catchment-scale sediment transport in glaciated basins remains poorly understood. Here, we estimate the effect of freeze-thaw processes on daily suspended sediment concentrations (SSC) in the Vent-Rofental basin, Austria. Using Bayesian change-point hierarchical regression, we assess the influence of streamflow, frozen ground extent (FGE), and diurnal freeze-thaw cycles (FTCs) across three distinct freeze-thaw states: thawing spring, thawed summer, and freezing autumn. While streamflow is the dominant driver of sediment transport, its effect is modulated by freeze-thaw conditions and an interaction with temperature. FGE was found to reduce daily SSC, attributed to a reduction in the sediment contributing area. A discernible shift in suspended sediment dynamics is observed as the catchment transitions from frozen to thawed, marked by a change-point when nearly all (97%) of the catchment is thawed. The thawed summer state exhibited the highest SSC due to elevated glacier melt. While the effect of diurnal FTCs on catchment-scale fluvial sediment dynamics is ambiguous, a credible temperature-adjusted effect in the thawing spring state may indicate enhanced sediment transport by amplifying snowmelt erosion. This study suggests that as glaciers retreat, snowmelt- and freeze-thaw-driven erosion, in addition to erosive rainfall, will become increasingly influential in determining sediment fluxes.
The recent combination of significantly reduced launch costs and the confirmed presence of water ice on the Moon presents new opportunities for lunar construction beyond the constraints of traditional In-Situ Resource Utilization (ISRU). This study investigates an alternative approach that incorporates Earth-supplied cement with lunar-derived resources to manufacture concrete directly on the lunar surface. In this concept, cement is transported from Earth, while lunar rocks are processed into aggregate and water ice is electrolyzed to provide the water and atmosphere necessary for concrete mixing. The resulting precast blocks are assembled into modular arch structures and covered with regolith for thermal and radiation protection. A comparative cost analysis shows that if launch costs fall from current levels (approximately US $1,410/kg) to projected levels under systems like Starship (US $10/kg), transportation costs for materials and equipment to build a habitat for two could drop from around US $138.6 million to just US $0.98 million. This roughly 99% reduction implies that conventional concrete-based construction may become economically viable for early lunar infrastructure. However, further research is needed in key areas such as performance of concrete structure under vacuum condition, in-situ water extraction efficiency, and optimization of regolith covering design.
Purpose of ReviewForest roads, which are important for accessing and managing forest areas, are particularly vulnerable to damaging impacts of severe climatic events. Understanding how weather changes affect forest roads is important for their efficient management and to ensure their reliability in supporting forest products supply chains. This paper reviews research conducted on the impact of climate factors on forest roads over the past two decades. The aim of our study was to develop a conceptual framework to support adaptation and mitigation strategies in forest road network management, ensuring sustainable wood flow despite a changing climate.Recent FindingsThrough a review of scientific articles and their results, we provided insights and recommendations to increase the resiliency of forest road infrastructures against the effects of climate change. Framed within the principles of climate-smart forestry, this study also offers practical suggestions to maintain the efficiency and safety of wood transportation networks under changing weather conditions, supporting sustainable forest operations and climate adaptation.SummaryThis review highlights how changes in precipitation and temperature patterns caused by climate change can impact forest road infrastructure and wood transportation. Based on the analysis of the reviewed articles, we identified key consequences such as increased erosion, road deformation, and reduced frozen periods. The research provides dedicated actions to ensure sustainability of forest resources and their infrastructure. This review is a key step towards more resilient and adaptive forest road management practices, helping to reduce the impacts of climate change on forest transportation and ecological systems.
Biomass residues from the agricultural industry, logging and wood processing activities have become a valuable fuel source. If processed under pyrolysis combustion, several products are generated. Bio-oil and gases are essential alternatives to fossil coal-based fuels for energy and electricity production, whose need is constantly growing. Biochar, the porous carbon-based lightweight product, often ends up as a soil fertilizer. However, it can be applied in other industrial sectors, e.g., in plastics production or in modifying cementitious materials intended for construction needs. This work dealt with the application of small amounts of softwood-based biochar up to 2.0 wt.% on hydration kinetics and a wide range of physical and mechanical properties, such as water transport characteristics and flexural and compressive strengths of modified cement pastes. In the comparison with reference specimens, the biochar incorporation into cement pastes brought benefits like the reduction of open porosity, improvement of strength properties, and decreased capillary water absorption of 7-day and 28-day-cured cement pastes. Moreover, biochar-dosed cement pastes showed an increase in heat evolution during the hydration process, accompanied by higher consumption of clinker minerals. Considering all examined characteristics, the optimal dosage of softwood-derived biochar of 1.0 wt.% of Portland cement can be recommended.
Root mechanical traits, including load for failure in tension (Fr), tensile strength (Tr), tensile strain (epsilon r), modulus of elasticity (Er), and tensile toughness (Wr), are critical for plant anchorage and soil stability. These traits are shaped by root morphology, type (absorptive and transport roots), and mycorrhizal associations (arbuscular mycorrhizal and ectomycorrhizal fungi). This study investigates the relationships among these traits. We examined mechanical traits across eight woody species with different mycorrhizal associations, categorizing roots into absorptive and transport types. Root morphological traits - root diameter (RD), specific root length (SRL), root tissue density (RTD), and root biomass (RB) - were measured. Tensile tests were conducted to assess mechanical properties. Statistical analyses, including regression and principal component analysis (PCA), were used to elucidate trait relationships. Transport roots exhibited superior mechanical properties compared to absorptive roots, with RD and RB showing significant positive correlations with mechanical traits. AM roots demonstrated higher tensile strength, strain, and toughness than EM roots. PCA highlighted RD and SRL as dominant factors influencing root mechanical performance, while RB contributed significantly to transport roots' structural stability. This study underscores the critical role of root morphological traits and mycorrhizal associations in determining mechanical performance. These findings highlight the ecological trade-offs between mechanical stability and resource acquisition, offering novel insights into root functional strategies and their implications for ecosystem stability.
Jadomycin B, produced by the soil bacterium Streptomyces venezuelae ISP5230, induces cytotoxicity in human breast cancer cells in vitro and has antitumoral effects in animal models. In models of multidrugresistant, triple-negative breast cancer, jadomycin B has shown promise as it is not a substrate of ABCB1 and ABCG2 drug efflux transporters. The generation of reactive oxygen species and inhibition of topoisomerases are potential mechanisms of jadomycin B-mediated DNA damage and apoptosis. However, the mechanisms of jadomycin B's anticancer activity have not been fully elucidated. By gradually exposing MDA-MB-231 triple-negative human breast cancer cells to jadomycin B, we hypothesized that resistance could be selected to further understand jadomycin B's pharmacological mechanisms. A 3-fold increase in the jadomycin B IC50 was observed in MDA-MB-231 cells exposed to increasing jadomycin B concentrations (0-3 mu M) over 7 months, herein 231-JB cells. The 231-JB cells were cross-resistant to jadomycin F and S but not to the comparator drugs mitoxantrone, doxorubicin, and SN-38. The 231-JB cells did not have increased mRNA expression of topoisomerase-2 nor ABCB1 and ABCG2. Cyclooxygenase-2 (COX-2) increased by 25-fold, but expression of prostaglandin E2 receptor 4 did not significantly change. Cotreatment with celecoxib (15-45 mu M), a COX-2 inhibitor, resensitized the 231-JB cells to jadomycin B (IC50 1/4 1.41 +/- 0.24 to 0.75 +/- 0.31 mu M vs 2.28 +/- 0.54 with 0 mu M celecoxib). To our knowledge, this work represents the first report of the involvement of COX-2 in jadomycin B activity in vitro, proving to be an exciting new target for the exploration of jadomycin B anticancer activity. Significance Statement: Cyclooxygenase-2 (COX-2), the rate-limiting enzyme in prostaglandin production, is associated with procancer signaling. COX-2, ABCB1, and ABCG2 overexpression are typically correlated in cancer, contributing to chemotherapy resistance. We observed increased COX-2, but not ABCG2 or