Characterizing vertical profiles of in-situ particle properties is relevant because being only based on the surface or column-integrated measurements cannot unambiguously conclude the radiative impact on aerosol. Vertical profiles of in-situ aerosol properties on-board an unmanned aerial vehicle (UAV) were measured above El Arenosillo (37.1 N,-6.7 W) in the southwest of Spain during four flight missions. Measured properties included particle number size distribution, total particle concentration and multiwavelength absorption coefficient up to 3100 m during cold season (February 4, 2022 and December 11, 2023) and warm season (September 20, 2023 and April 2, 2024). The heterogeneity of particle properties has been shown around two types of events: a mineral particle event of desert origin during cold season and a new particle formation event during warm season. During cold season, a comparison between the flight missions with and without desert dust episodes shows that mineral particles decrease the planetary boundary layer (PBL) height. This behavior is probably related to absorber particles aloft atmosphere, which traps solar radiation and heat up the upper layer of the atmosphere and deteriorates the vertical dispersion. In the literature, this effect is called as 'dome effect'. During warm season, new particle formation was observed above PBL. This event could be related to the presence of precursor gases in the residual layer, and enhanced by a low concentration of pre-existing particles. The characteristic parameter during the observed event was the fine-to-total particle volume concentration ratio close to zero. These observations highlight the necessity to establish a long-term multi-temporal monitoring of vertical profiles for atmospheric parameters onboard UAV systems and to integrate in Earth observations networks. For example, radiative forcing is usually estimated from surface data, but the heterogeneity in the vertical profiles of atmospheric particles properties, which are used to the forcing quantification, is a result of inaccuracies.
Char and soot represent distinct types of elemental carbon (EC) with varying sources and physicochemical properties. However, quantitative studies in sources, atmospheric processes and light-absorbing capabilities between them remain scarce, greatly limiting the understanding of EC's climatic and environmental impacts. For in-depth analysis, concentrations, mass absorption efficiency (MAE) and stable carbon isotope were analyzed based on hourly samples collected during winter 2021 in Nanjing, China. Combining measurements, atmospheric transport model and radiative transfer model were employed to quantify the discrepancies between char-EC and soot-EC. The mass concentration ratio of char-EC to soot-EC (R-C/S) was 1.4 +/- 0.6 (mean +/- standard deviation), showing significant dependence on both source types and atmospheric processes. Case studies revealed that lower R-C/S may indicate enhanced fossil fuel contributions, and/or considerable proportions from long-range transport. Char-EC exhibited a stronger light-absorbing capability than soot-EC, as MAE(char) (7.8 +/- 6.7 m(2)g(-1)) was significantly higher than MAE(soot) (5.4 +/- 3.4 m(2)g(-1))(p < 0.001). Notably, MAE(char) was three times higher than MAE(soot) in fossil fuel emissions, while both were comparable in biomass burning emissions. Furthermore, MAE(soot) increased with aging processes, whereas MAE(char) exhibited a more complex trend due to combined effects of changes in coatings and morphology. Simulations of direct radiative forcing (DRF) for five sites indicated that neglecting the char-EC/soot-EC differentiation could cause a 10 % underestimation of EC's DRF, which further limit accurate assessments of regional air pollution and climate effects. This study underscores the necessity for separate parameterization of two types of EC for pollution mitigation and climate change evaluation.
Peloid is a natural product developed during the maturation process between a clay material and water and is used in health and wellness centres due to its mineralogical, physiochemical and biological properties. However, the potential therapeutic value of clays in Portugal has not been fully investigated. Therefore, the main objective of this research is to identify the effects of two mineralized waters: thermo-mineral water (sulphurous and hydroxylated water abundant in chloride ions, sodium and calcium) and seawater, on three residual soils from Alentejo, from a morphological, mineralogical and chemical perspective. The peloids morphology is more homogeneous than the residual soils, and the particle size decreases during the maturation process. Thermo-mineral water enriched the peloids in smectite (58-76 %), while seawater newly formed Na-minerals (decreasing smectite contents to 39-54 %). Smectite is essentially montmorillonite, although there is nontronite and beidelite. The residual soils and peloids have a silicilastic composition (32.23-52.85 %), between 14.22 and 20.53 % of Al2O3, and besides smectite, the mineralogical composition is composed of salts (only in seawater peloids), feldspars, iron oxides, carbonates, and quartz. Morphology and mineralogy enhance the influence of waters in peloids properties and suggest that this samples have potential therapeutic value. Furthermore, physicalchemical, rheological, thermal and biological analysis are needed to support these findings.
Soil-plant-atmosphere interaction (SPAI) plays a significant role on the safety and serviceably of geotechnical infrastructure. The mechanical and hydraulic soil behaviour varies with the soil water content and pore water pressures (PWP), which are in turn affected by vegetation and weather conditions. Focusing on the hydraulic reinforcement that extraction of water through the plant roots offers, this study couples advances in ecohydrological modelling with advances in geotechnical modelling, overcoming previous crude assumptions around the application of climatic effects on the geotechnical analysis. A methodology for incorporating realistic ecohydrological effects in the geotechnical analysis is developed and validated, and applied in the case study of a cut slope in Newbury, UK, for which field monitoring data is available, to demonstrate its successful applicability in boundary value problems. The results demonstrate the positive effect of vegetation on the infrastructure by increasing the Factor of Safety. Finally, the effect of climate change and changes in slope vegetation cover are investigated. The analysis results demonstrate that slope behaviour depends on complex interactions between the climate and the soil hydraulic properties and cannot be solely anticipated based on climate data, but suctions and changes in suction need necessarily to be considered.
Contact Lens (CLs) are often disposed of via toilet or sinks, ending up in the wastewater treatment plants(WWTPs). Millions of CLs enter WWTPs worldwide each year in macro and micro sizes. Despite WWTPs'ability to remove solids, CLs can persist and potentially contaminate watercourses and soils. This study evaluates whether different CLs degrade in WWTP aeration tanks. Six daily CLs (Nelfilcon A,Delefilcon A, Nesofilcon A, Stenfilcon A, Narafilcon A, Somofilcon A) and four monthly CLs (Lotrafilcon B,Comfilcon A, Senofilcon A, and Samfilcon A) were immersed in aeration tanks for twelve weeks. Theirphysical and chemical properties, including water content (WC), refractive index (RI), chemical prop-erties (Fourier Transform Infrared Spectroscopy), and mechanical properties were assessed. Results show that all CLs maintained their physical appearance after 12 weeks. Neither Nelfilcon A norNarafilcon A exhibited significant changes in WC and RI, (p>0.05, Tukey test), while other daily lensesshowed variations in at least one parameter. Among monthly CLs, only Senofilcon A showed significant differences in both WC (p0.05 Tukey test). However, Somofilcon A displayed significant changes in stress at break (p<0.0001,Tukey test), and Elongation at Break (p<0.05, Tukey test). No changes were found in the chemicalstructure of any CLs suggesting that twelve weeks in WWTP aeration tanks is insufficient for CLsdegradation. Thesefindings highlight CLs as a potential emerging pollutant, emphasizing their persis-tence in sludge or migration into watercourses and soils (c) 2025 The Authors. Publishing services by Elsevier B.V. on behalf of KeAi Communications Co. Ltd. Thisis an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
Use of forest biomass may induce changes in the aerosol emissions, with subsequent impacts on the direct and indirect climate effects of these short-lived climate forcers. We studied how alternative wood use scenarios affected the aerosol emissions and consequent radiative forcing in Finland. In all alternative scenarios, the harvest level of forest biomass was increased by 10 million m3 compared to the baseline. The increased biomass harvest was assigned to four different uses: (i) to sawn wood, (ii) to pulp-based products, (iii) to energy biomass combusted in small-scale appliances or (iv) to energy biomass combusted in medium-to-large scale boilers. Aerosol emissions (black carbon (BC), organic carbon (OC) and sulphur dioxide (SO2)) under these scenarios were estimated using displacement factors (DFs). The global aerosol-climate model ECHAM-HAMMOZ was used to study instantaneous radiative forcing due to aerosol-radiation interactions (IRFARI) and effective radiative forcing (ERF), based on the differences in aerosol emissions between the alternative wood use scenarios and the baseline scenario. The results indicated that the use of sawn wood and energy biomass combusted in medium- to large-scale boilers decreased radiative forcings, implying climate cooling, whereas the increased use of pulpwood increased them. Energy biomass combustion in small-scale appliances increased IRFARI by 0.004 W m-2 but decreased ERF by -0.260 W m-2, specifically due to a strong increase in carbonaceous aerosols. Alternative use of forest biomass notably influenced aerosol emissions and their climate impacts, and it can be concluded that increased forest biomass use requires a comprehensive assessment of aerosol emissions alongside greenhouse gases (GHGs). Given the consequent reduction in radiative forcing from aerosol emissions, we conclude that the greatest overall climate benefits could be achieved by prioritising the production of long-lived wood-based products.
Atmospheric brown carbon (BrC) from wildfires is a key component of light-absorbing carbon that significantly contributes to global radiative forcing, but its atmospheric evolution and lifetime remain poorly understood. In this study, we investigate BrC evolution by synthesizing data from one laboratory campaign and four aircraft campaigns spanning diverse spatial scales across North America. To estimate initial conditions for evaluating plume evolution, we develop a method to parametrize the emission ratios of BrC and other species using commonly measured inert tracers, acetonitrile and hydrogen cyanide. The evolution of BrC absorption in the free troposphere is characterized as a function of hydroxyl radical (OH) exposure, yielding an effective photochemical rate constant of 9.7-1.6 +4.8 x 10-12 cm3 molecule-1 s-1. The relatively slow reaction rate results in small BrC decay within the first few hours after emission, making it difficult to distinguish from source variability. This helps explain the absence of clear evolutionary trends in near-field studies. Assuming an OH concentration of 1.26 x 106 molecules cm-3, this rate constant corresponds to an e-folding lifetime of approximately 23 h. After extensive photooxidation (OH exposure similar to 1012 molecules cm-3 s), 4 +/- 2% of the emitted BrC persists, representing a recalcitrant fraction with potential long-term climate impacts. These results improve our understanding of BrC variability and photochemical processing and provide critical constraints for modeling its impacts on climate.
Thermochemical processing of biowaste generates renewable carbon-rich materials with potential agronomic uses, contributing to waste valorization. This study evaluates the application of hydrochar obtained from hydrothermal carbonization of food waste, those obtained by different post-treatments (washing, aging, and thermal treatment), as well as biochar obtained by pyrolysis as soil amendments. For this purpose, the effect of char addition (1-10 wt% d.b.) on a marginal agricultural soil on germination and growth of Solanum lycopersicum (tomato) plants was assessed. All the hydrochars exhibited a chemical composition suitable for agronomic use, characterized by high nutrient content, abundant organic matter, and low concentration of phytotoxic metals. In contrast, biochar exceeded the permissible limits for Cr, Cu, and Ni concentrations rendering it unsuitable for application to agronomic crops. The high temperature of thermal post-treatment and pyrolysis favored mineral and heavy metal concentration while washing significantly reduced nutrient content (N, S, P, K, Mg) along with the electrical conductivity. The addition of biochar or both washed and thermally post-treated hydrochar negatively affected tomato growth. Reduced chlorophyll content was associated with the decreased expression of genes encoding enzymes involved in antioxidant metabolism. This led to photosynthetic membrane damage, as evidenced by chlorophyll fluorescence-related parameters. Conversely, the addition of aged (<= 5 wt %) and fresh (1-10 wt%) hydrochars increased both germination and plant growth compared to unamended soil, indicating that hydrochar from food waste does not require additional post-treatments to be used as a soil amendment.
Loose sandy soil layers are prone to liquefaction under strong earthquakes, causing damage to civil engineering structures inside or upon the liquefied ground. According to the present Japanese design guideline on liquefaction countermeasures for river levees, the entire depth of the liquefiable subsoil below river embankments should be improved. However, this approach is not economical against deep liquefiable subsoil. To rationalize the design approach, this contribution investigated the performance of a floating-type cement treatment method, in which only the shallower part of the liquefiable subsoil is reinforced. A series of centrifuge shaking table model tests was conducted under a 50g environment. The depth of improvement (cement treatment) was varied systematically, and the effect of the sloping ground was examined. The experimental results revealed that the settlements of river embankments can be reduced linearly by increasing the depth of improvement. Moreover, the acceleration of embankments can be reduced drastically by the vibration-isolation effect between the cement-treated soil and the liquefiable soil. These effects contribute to the safe retention of the embankment shape even when the liquefied sloping ground causes lateral flows. Towards practical implementation, discussions on the effect of permeability on cement-treated soil were expanded. Furthermore, the stress acting on cement-treated soil during shaking was measured using an acrylic block to explain the occurrence of cracks in the soil. (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/).
Predicting cumulative surface slope displacements induced by rainfall infiltration is crucial for accurately assessing the risks to potentially affected infrastructure. In this paper the numerical modelling of the case history of Miscano slope is presented. Plaxis 2D code has been used adopting two constitutive laws: the linear elastoplastic model (Mohr-Coulomb, MC) and the Hardening Soil with small strain stiffness (HSsmall). The aim is to test the suitability of these constitutive laws in predicting the hydro-mechanical behaviour of clayey soil slope. Based on long-term field measurements, the parameters of MC and HSsmall have been determined by back analysing the first-year field measurements in terms of cumulative surficial horizontal displacements and pore water pressure. Subsequently, the numerical models have been validated against the analogous field measurements collected from the second year. The numerical models predict with a good agreement the field measurements for both years. In terms of cumulative surficial horizontal displacements, the HSsmall underestimates the field measurements by 21.2% at the end of the first year, while that based on MC exhibits a 32.8% overestimation. Moreover, the initialization procedure clearly affects the cumulative surficial horizontal displacements results obtained with both the HSsmall and MC models for the second year. In fact, the best results have been achieved when the second-year net rainfall have been applied starting from the initial phase used to generate the lithostatic stress state.