This session focuses on advances in the assessment, monitoring, and recovery of contaminated soils, providing a platform for interdisciplinary discussion across soil science, environmental geochemistry, ecology, and restoration science. We invite colleagues to present their studies on the following topics: Soil health and the mitigation of contaminating processes; Assessment of contaminated areas and risk using classical techniques, bioindicators, biomarkers, and/or digital tools; Evaluation of the cost-effectiveness of techniques and materials (e.g. phytoremediation, technosols, biochar, nanoparticles, and other organic and inorganic amendments) for soil remediation processes and their environmental applications; Modelling the behaviour of potentially hazardous substances and nutrients in contaminated and remediated soils; Soil-plant interactions in contaminated and recovered environments; Monitoring and the environmental response of ecosystems after the implementation of remediation programmes; Legal frameworks and the limitations of soil remediation strategies; among other.
This session will provide an opportunity to present studies and establish new partnerships, with the aim of developing multidisciplinary strategies that can contribute to the assessment and remediation of contaminated sites.
Orals: Thu, 7 May, 14:00–16:45 | Room 0.11/12
Soil degradation driven by long-term anthropogenic pressure affects up to 70% of European soils and poses major environmental and socio-economic risks. Nature-Based Solutions, particularly phytoremediation, have attracted attention as sustainable strategies for soil restoration. However, their long-term effects on soil functioning remain insufficiently understood. This study focuses on a contaminated site in northern France (Carrières-sous-Poissy, Île-de-France), where poplar (Populus sp.) plantations have been established as a phytoremediation measure. The site’s contamination is a result of extensive and long-term deposition of urban and industrial waste from the surrounding area, combined with the former use of improperly treated wastewater from the Paris region as fertilizer. The site includes two experimental fields with poplar plantations representing distinct stages of phytoremediation: a long-term stand installed 13 years ago, and a recently installed, one year old stand. The main objectives of this study are to 1) evaluate the contribution of poplar plantations to soil rehabilitation, 2) observe how contamination shapes key soil functions, and 3) assess the robustness of selected soil health indicators. To achieve these aims, it combines physicochemical indicators (pH, water holding capacity, soil texture, organic matter content), with biological indicators (extracellular enzymatic activity of hydrolases, cellulose degradation capacity, and soil respiration). Enzymatic analyses include β-glucosidase (β-GLU), urease (URE), alkaline phosphatase (PAK), acid phosphatase (PHOS) and arylsulfatase (ARS) activity, serving as proxies for major nutrient cycles (C, N, P, S). Cellulose degradation capacity represents a cost-effective, accessible, comprehensive indicator of soil functionality. Lastly, soil contamination is studied through targeted analysis of heavy metals and non-targeted screening of organic micropollutants that provides a broader understanding of the complexity of the contamination profile. Overall, grounded in systematic monitoring and supported by the HE EDAPHOS and PROLIPHYT projects, this study provides insights into the relationship between phytoremediation, contamination, and soil functionality.
How to cite: Chatzimarinaki, C., Manier, N., Boisson, Y., Huynh, N., Chalot, M., and Ciadamidaro, L.: Long-Term Nature-Based Solutions: Poplar Phytoremediation Effects on Soil Contamination and Soil Functionality, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-2978, https://doi.org/10.5194/egusphere-egu26-2978, 2026.
Arsenic (As) contamination is widespread in soils throughout the world, but remediation options can be limited, especially in anoxic conditions where trivalent arsenite (As(III)) dominates As speciation in the pore solution. As(III) adsorbs weakly to most sorbents and thus spreads readily in anoxic aquifers. Several laboratory assays indicate that in suspensions of zerovalent iron (ZVI), dissolved As(III) can be immobilised in several ways including reduction to insoluble zerovalent As (As(0)) or physical encapsulation in neoformed iron oxides. We previously exposed soil suspensions from an anoxic aquifer, in which As(III) predominates in solution, to ZVI suspensions under anoxic conditions, and quantified As immobilisation kinetics as well as the molecular speciation of Fe and As using X-ray absorption spectroscopy (XAS). As(III) was immobilised by oxidation to pentavalent arsenate (As(V)) which sorbed strongly to these oxides.
The current study investigated the immobilisation mechanisms of As(III) following in-situ injection of polyacrylic acid-coated nano-sized ZVI in the same anoxic aquifer. As concentrations measured at different distances from ZVI injection showed a heterogeneous response where a retarded As reduction, i.e. only after a year of monitoring, was observed in only a selected few groundwater wells. Eh and pH were subsequently measured, 2 years after ZVI injection, as a function of depth and distance away from ZVI injection using dynamic groundwater sampling, and As speciation was determined in extracted porewaters. Moreover, intact cores were sampled using sonic drilling, and the molecular speciation of As and Fe were characterised as a function of depth using XAS.
Lower Eh and higher pH values were found in the field compared to the earlier lab studies on soil suspensions from the same aquifer. As(III) was also not oxidised to As(V). Instead, both XANES and EXAFS analysis suggested that zerovalent As was formed, albeit not homogeneously throughout the treated aquifer. Unexpectedly, ZVI still occurred in zerovalent form to a large part despite the high surface area of nano-sized ZVI. This study thus illustrates the difficulty of reproducing field conditions during laboratory experiments and the sensitivity of immobilisation to geochemical conditions in the field. Moreover, immobilisation as zerovalent As did not sufficiently reduce As(III) concentrations, which remained the predominant As species in most porewaters, most likely because of the observed heterogeneity of the ZVI distribution in the aquifer.
How to cite: Cornelis, G., Kieschnik-Llamas, C., Sjöstedt, C., Gustafsson, J. P., and Berggren Kleja, D.: In-situ geochemistry of arsenite remediation by nanozerovalent iron in an anoxic aquifer: field versus lab, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-7195, https://doi.org/10.5194/egusphere-egu26-7195, 2026.
Antimicrobial resistance (AMR) represents a critical One Health challenge, linking human, animal, and environmental health. Agriculture, particularly the use of livestock manure as fertilizer, contributes significantly to the dissemination of antibiotic resistance genes (ARGs) and mobile genetic elements (MGEs) through soils and crops, posing risks to food security and public health. This study integrates multiple experiments to elucidate the fate of antibiotics and the dynamics of ARGs across the manure–soil–plant continuum. Pot experiments with pig manure-amended soil revealed enriched ARGs in the carrot rhizosphere and phyllosphere. Manure application increased ARG bioaccumulation in carrot tubers (up to 124-fold for specific genes) and facilitated transfer from skin to tuber. Estimated daily human ARG intake from manured carrots reached ~3 × 107 copies, but peeling reduced this by 28–91%. Field-scale isotope tracing (13C-labeled sulfamethoxazole) in lettuce demonstrated rapid antibiotic dissipation in non-planted soils (>98% in 180 days), yet rhizosphere accumulation and root-to-leaf translocation. Co-application with swine manure amplified soil ARG abundance (up to 5.35-fold) and root enrichment (2.38-fold), driven primarily by MGEs. High-risk ARGs persisted in leaves despite low residues. In paddy fields, swine compost elevated ARG abundance in soil and rice roots over growth stages, with increased detection frequencies indicating transfer from compost and irrigation water. No significant ARG differences appeared in grains across treatments. Metagenomic analysis via 13C-DNA stable isotope probing distinguished antibiotic-degrading bacteria (ADB) from non-degrading ones in contrasting soils. ADB harbored diverse chromosomal ARGs co-localized with MGEs and degradation genes, suggesting high horizontal gene transfer potential and soil-specific resistome networks. Hydroponic lettuce studies showed that manure sterilization reduced endophytic ARG/MGE subtypes by 50–86%, diminished pathogenic bacteria, and lowered high-risk ARG intake, highlighting its efficacy for risk mitigation. These findings provide comprehensive evidence that manure application propagates AMR through synergistic antibiotic–fertilizer effects, MGE-mediated transfer, and plant uptake. Integrated management, including manure sterilization, peeling of root vegetables, and soil-specific strategies, is essential to mitigate risks at the human–animal–environment interface.
How to cite: Wang, F., Heiling, M., Fujisawa, M., and Dercon, G.: Tracing antibiotic fate and antimicrobial resistance dynamics across the manure–soil–plant continuum, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-7955, https://doi.org/10.5194/egusphere-egu26-7955, 2026.
The Mining District of Almadén (Spain) provides a valuable natural setting for studying the biogeochemical behavior of mercury (Hg) under conditions shaped by long-term, legacy contamination. This study presents an evaluation of the Hg cycle through the simultaneous characterization of soils, atmospheric dynamics and Pinus pinea tissues (leaves and bark). The results reveal that, although soils present extreme concentrations (range: 2.9 – 123 mg kg-1 dominated by stable species (α-cinnabar), there is a critical labile fraction associated with organic matter and metacinnabar that acts as a continuous source of re-emission. Mobile monitoring demonstrated a drastic dichotomy in total gaseous mercury (TGM) levels, identifying nighttime atmospheric stability as the main forcing mechanism for Hg accumulation in the tree canopy. Pyrolytic speciation in vegetation revealed a functional divergence between tissues: the cortex acts as a passive physical trap for cinnabar and Hg2+ while the needles function as active physiological sinks of gaseous Hg0, validating an intracellular immobilization mechanism. Lastly, data integration indicates that the pine tree functions as a "biological pump" that recirculates atmospheric mercury into the soil; however, this cycle is disrupted in urban settings by street cleaning and management, which attenuates the soil burden in comparison to natural systems; and by wind driven atmospheric dilution.
How to cite: Avalos, O., Barquero Peralbo, J. I., Higueras Higueras, P. L., and Meloni, F.: Integrated Assessment of Mercury Cycling in Pinus pinea: From Soil Re-emission and Nocturnal Atmospheric Accumulation to Foliar Immobilization, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-8050, https://doi.org/10.5194/egusphere-egu26-8050, 2026.
Human activities release Pharmaceutically Active Compounds (PhACs) onto arable land, where they can accumulate and disrupt the ecological balance. The soil’s microbial community continuously alters the composition of organic matter, as it serves as the primary source of nutrients for this matter. The quality and quantity of organic matter may vary even within a single vegetation period. Observing the extent of transformation in the different phases is essential, as organic matter is primarily responsible for the soil’s ability to retain micropollutants. An incubated sorption experiment was conducted to simulate a vegetation period using a Phaeozem, examining this question. Enzyme activity results indicate that the microbial community transforms soil organic matter, reducing its quantity and thus its ability to retain PhACs. At the beginning of the incubation period, among the physicochemical properties of PhACs, the H-donor/acceptor counts and the size of their van der Waals surface area were the determining factors in the sorption processes. At the end of the incubation period, due to the reduction in organic matter and the transformation of functional groups, the adsorbed PhACs decreased significantly, while desorption increased because electrostatic interactions began to dominate the sorption processes. Consequently, the mobility rate of the PhACs with hydrophobic properties may increase in the arable land by the end of the vegetation period. The primary properties of PhACs identified should be considered when assessing soil persistence. It’s vital to account for the temporal evolution of soil conditions and avoid relying on a single observation, as this only partially represents the soil’s actual state.
The presentation is based on a paper with the title published in the Journal of Environmental Management.
Funding: National Research, Development and Innovation Office K142865 and DKOP- 23_03, Bolyai Research Scholarship (BO/00 199/25/10)
How to cite: Szalai, Z., Szabó, L., Kondor, A. C., Vancsik, A., Király, C., Booth, C., and Bauer, L.: Soil organic matter decomposition as a key driver of pharmaceutical retention, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-11874, https://doi.org/10.5194/egusphere-egu26-11874, 2026.
Soil contamination derived from abandoned mining sites represents one of the most persistent environmental threats in Europe and worldwide. In regions such as the Principality of Asturias (NW Spain), historical mercury mining has generated large areas of affected sites, where soils exhibit high concentrations of arsenic (As) and mercury (Hg). In recent years, the use of engineered nanomaterials has emerged as a promising approach to modify contaminant mobility in soils, either by enhancing immobilization or by improving extractability. However, significant uncertainties remain regarding the behavior of metalloids such as arsenic (As), whose interactions with soil minerals may differ substantially when nanomaterials are introduced. This study evaluates whether graphene oxide (GOx) can enhance As phytoremediation, focusing on plant uptake and accumulation in a mining polluted soil. A pot experiment was conducted using soil (S) from El Terronal, an abandoned mining site, and soil amended with 1% GOx nanoflakes (SGO). Eupatorium cannabinum plants were transferred to the pots (n = 10 per treatment) and grown for 7 and 30 days. Plant performance (biomass, shoot/root length) and As concentration and speciation in tissues were determined. Soil physicochemical properties, total concentration, As availability (TCLP), and As fractionation (Wenzel method) were analysed.
GOx significantly modified As dynamics in the soil-plant system. Leaching tests revealed higher As release in GOx-amended soils, likely due to FeOOH dissolution and reduction, as well as protonation of GOx under acidic leaching conditions (soil pH decrease after GOx application). Plant uptake showed that GOx enhanced As retention in roots, promoting phytostabilization rather than phytoextraction. After 30 days, As concentration in roots increased markedly in SGO (442 mg kg⁻¹; As(III): 11.1%) compared to S (38.5 mg kg⁻¹; As(III): 5.4%). Shoots also showed higher As content in plants growing in the SGO treatment (73.0 mg kg⁻¹; As(III): 15.8%) than in S (21.3 mg kg⁻¹; As(III): 11.6%). However, translocation factors (TF) remained <1 in all cases (S: 0.76; SGO: 0.17), indicating restricted movement of As to aerial tissues. Bioaccumulation factors (BAF) exceeded 1 in both soils and increased under GOx (S: 1.96; SGO: 3.94), reflecting enhanced As accumulation rather than translocation.
Overall, GOx enhanced arsenic accumulation in roots, highlighting its potential for phytostabilization-based remediation strategies. These results provide important insights into the behavior of GOx in real contaminated soils and emphasize the evaluation of nanoremediation technique as post-mining soil restoration solution.
References:
[1] Baragaño, D., Forján, R., Welte, L., & Gallego, J.R. (2020). Nanoremediation of As and metals polluted soils by means of graphene oxide nanoparticles. Scientific Reports 10(1), 1896
[2] Peña-Álvarez, V., Baragaño, D., Prosenkov, A., Gallego, J.R., Peláez, A.I. (2024). Assessment of co-contaminated soil amended by graphene oxide : effects on pollutants, microbial communities and soil health. Ecotoxicology and Environmental Safety 272, 116015.
How to cite: Salgado-Almeida, B., Sánchez, S., González, A., Gallego, J. L. R., Berrezueta, E., and Baragaño, D.: Enhancing arsenic phytoremediation through graphene oxide–induced mobilization in polluted mining soils, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-12333, https://doi.org/10.5194/egusphere-egu26-12333, 2026.
This study combines batch adsorption experiments and surface complexation modelling to investigate the interactions of arsenate [As(V)] and arsenite [As(III)] with agricultural soils from an arsenic (As) contaminated district of Punjab, India. Batch adsorption studies were conducted to investigate the impact of contact time, As loadings, ionic strength and solution pH on As retention under conditions representative of the regional environment. As adsorption was significantly higher in surface soil layers than in bottom layers, largely due to variations in surface area, organic matter content, pH, and mineralogical components. Experimental data were interpreted using a generalized composite triple layer model (GC-TLM), representing the average surface reactivity of the natural soil assemblage. Modelling results indicate that As(V) predominantly forms inner-sphere surface complexes, whereas As(III) forms both inner and outer-sphere complexes. The model successfully reproduced adsorption isotherms and pH-edge behaviour within reasonable RMSE, demonstrating its applicability to natural soils. These findings improve the mechanistic understanding of As-soil interactions and provide a basis for predicting As mobility in agricultural soils of Punjab.
How to cite: Nazir, H. and Moozhikkal, R.: Arsenic Interactions in Agricultural Soils from Punjab, India: Insights from Triple Layer Surface Complexation Modeling, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-13204, https://doi.org/10.5194/egusphere-egu26-13204, 2026.
How reactive is a new metal contamination compared to the same metal already present in a soil? After a contamination event, upon hydrological fluctuations and associated redox variations, natural processes of redistribution and mineral transformation impact the speciation of the allochthonous metal input, thus affecting its (bio)availability and toxicity. This may lead to homogenization of the total metal pool of the soil with respect to the autochthonous metal, or to a shift in the total metal reactivity and associated risk. Because the terms “redistribution” or “natural attenuation” do not properly catch the meaning of this concept, the new term “natural assimilation” is proposed, that encompasses both the spatial redistribution and the parallel change in speciation of an allochthonous metal input in a soil that already contains a given amount of the same metal (autochthonous). Although such processes have been relatively well studied at the bulk soil scale, little is known about how the new metal input behaves compared to the preexisting soil metal pool at the microscopic scale, mainly because of technical difficulties in distinguishing autochthonous and allochthonous metal phases at that micro-scale.
Here, we are developing a methodology to allow such a distinction, by using isotope tracers to differentiate two metal pools in the soil, and combining spatially resolved analysis of the metal source proportions (isotope ratios mapped by laser ablation-inductively coupled plasma-mass spectrometry, LA-ICP-MS) and of the metal speciation (by synchrotron-based micro-X-ray absorption spectroscopy). In this pilot study, we performed laboratory incubations of natural soils already rich in iron (Fe) and zinc (Zn), in which isotopically labelled Zn-ferrihydrite (enriched in 57Fe and 68Zn) was amended. We then exposed the soil microcosms to wetting-drying cycles over several months in order to trigger redox fluctuations and subsequent Fe and Zn redistribution and transformation. Our preliminary 57Fe Mössbauer spectroscopy data shows significant oscillations of the Fe oxidation state along with redox cycles. In parallel, we observe mineral transformation and reductive dissolution of the Zn-ferrihydrite within a few weeks along with Fe and Zn release into the soil solution. Thin sections of the reacted soils will first be mapped by micro-XANES at the Fe and Zn K-edges to determine the Fe and Zn speciation with a spatial resolution, and subsequently by LA-ICP-TOF-MS to determine the Fe and Zn source distribution.
This project is expected to create a proof-of-concept applicable to many environmental systems and experimental setups, opening new avenues of research on the fate of metallic elements in soils and sediments, with a focus on the differential reactivity of several sources of the same metal.
How to cite: Lefebvre, P., Yao, Y., Umfahrer, B., Günther, D., and Kretzschmar, R.: Tracking the mechanisms of natural assimilation of metal contaminations at the micro-scale: a pilot study, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-13586, https://doi.org/10.5194/egusphere-egu26-13586, 2026.
The digital transformation and the transition towards low-carbon energy systems have intensified global demand for mineral resources, particularly those classified as Critical Raw Materials (CRM) by the European Union (EU). In this context, strontium (Sr), included in the EU CRM list since 2020, has gained strategic relevance during the last years. Spain plays a key role in the European strontium supply chain, with the Montevive celestite deposit (Granada, southern Spain) representing the largest strontium reserve in the EU. However, the progressive exploitation of lower-grade ores and the potential presence of hazardous trace elements raise concerns regarding both resource efficiency and occupational health.
This study, developed within the framework of the ROTATE project, aims to characterize the elemental composition of the Montevive celestite deposit, evaluate the presence of CRMs and rare earth elements (REEs), and assess the potential health risks to mine workers. A total of 22 soil samples were collected from five distinct mining areas (CDS, FDM, PIS, LAN, and D) and analyzed using X-ray fluorescence (XRF) and inductively coupled plasma techniques (ICP-MS/ICP-OES). Method validation was evaluated through certified reference materials and duplicate sample analyses.
Accuracy assessment demonstrated that ICP techniques significantly outperformed XRF, allowing reliable quantification of 34 elements contained in the certified reference materials, compared to only 20 elements detected by XRF. Precision assessment based on duplicate ICP analyses showed high analytical precision, with coefficients of variation below 5 % for 40 analytes, which exhibited concentrations above the quantification limit.
The average mineralogical composition was dominated by celestine, calcite, quartz and magnesite. Spatial variability within the deposit was evaluated using statistical analyses (Tukey’s HSD tests), revealing marked compositional differences in the LAN area relative to the remaining zones, with strong negative correlations between silicate phases (SiO2 and Al2O3) and sulphate minerals (SrSO4 and BaSO4). Similarly, LAN sector exhibited higher total rare earth element concentrations than the other areas, dominated by Ce, La, Nd and Y, indicating a potential secondary CRM resource.
Finally, a quantitative occupational health risk assessment was conducted considering inhalation of airborne particulate matter as the sole relevant exposure pathway, under a conservative worst-case scenario assuming the absence of personal protective equipment. For this exposure route, both non-carcinogenic and carcinogenic risks remained well below accepted regulatory thresholds for all evaluated elements considered individually, as well as for the aggregated risk (Hazard Quotient < 1; Carcinogenic Risk < 10-5). Considering the dust control measures and personal protective equipment currently implemented at the site, occupational exposure levels and associated health risks for workers are expected to be negligible.
Overall, this study provides an integrated assessment of resource potential, analytical reliability, and occupational health risks in a strategic European strontium deposit, supporting informed decision-making for sustainable mining and critical raw material supply in the EU.
How to cite: Izquierdo-Díaz, M., Serrano García, H., Montalvo Piñeiro, J., Barrio-Parra, F., Sánchez-Canales, M., De Miguel García, E., and Ariza-Rodríguez, N.: Comparison of XRF and ICP Techniques for Geochemical Characterization of a Celestite Deposit, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-20680, https://doi.org/10.5194/egusphere-egu26-20680, 2026.
The global energy transition is expected to substantially increase the demand for critical metals, particularly nickel, which plays a key role in the production of batteries for electric vehicles. This growing pressure on mineral resources also leads to the generation of large volumes of mining residues, raising concerns about soil contamination and long-term environmental impacts. Nature-based solutions, such as phytomining / agromining, have emerged as promising strategies to both mitigate soil contamination and promote the recovery of valuable metals from mining wastes.
In this study, we investigate the potential of Typha domingensis for nickel phytoextraction from lateritic nickel mining residues, predominantly composed of nickel-bearing goethite. A field experiment was established with four treatments and four replicates: (i) fertilised control, (ii) fertilisation combined with citric acid addition, (iii) fertilisation combined with microbial inoculation, and (iv) fertilisation combined with both microbial inoculation and citric acid. Plants are cultivated for 120 days to maximise their metal translocation potential to aboveground biomass, representing the first of three planned cutting cycles per year.
The experimental design aims to evaluate how organic acids and microorganisms may enhance nickel bioavailability and plant uptake under field conditions, and also test a non-hyperaccumulator plant as a phytoextractor. Plant biomass from the first harvest will be collected in March 2026, and plant tissues will be analysed for nickel concentration following microwave-assisted acid digestion (EPA 3052) and analysis by ICP-OES.
This contribution presents the experimental framework and first insights from the ongoing field trial, highlighting its relevance for the assessment of cost-effective and scalable remediation strategies for nickel-contaminated soils and mining residues. By integrating phytoextraction into the broader context of the energy transition, this study contributes to the discussion on sustainable land management and the reuse of mining wastes through nature-based solutions.
How to cite: Castilho, Y., Duim Ferreira, A., Varussa, A., Trentin, T., Gomes Viana, D., and Osório Ferreira, T.: Nickel phytoextraction by Typha domingensis in lateritic mining residues: first insights from a field trial, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-13201, https://doi.org/10.5194/egusphere-egu26-13201, 2026.
Keywords: Agriculture, Soil quality, Trace elements contamination, Portable XRF.
Acknowledgement: FTA acknowledges a STFT, Ministry of Science and Technology (Bangladesh) scholarship. AR acknowledges a Cookson Scholarship. RC acknowledges a PGRTA Studentship from the University of Manchester (UoM). We thank all the technical support staff in the Manchester Analytical Geochemistry Unit at the UoM for the PXRF and laboratory facilities.
References
1. Zhao et al. (2014). https://doi.org/10.1016/j.scitotenv.2013.09.086
2. Islam et al. (2024). https://doi.org/10.1016/j.envres.2024.118551
3. Hossain (2019). https://doi.org/10.1002/gj.3595
4. FAO (2004). https://faolex.fao.org/docs/pdf/est97999E.pdf
How to cite: Ahmed, F. T., Roshan, A., Cracroft, R., Richards, L. A., and Polya, D. A.: Portable XRF (PXRF) Analysis of Agricultural Soils in Central Bangladesh - Approaches to Quantify Anthropogenic Trace Element Inputs , EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-23001, https://doi.org/10.5194/egusphere-egu26-23001, 2026.
Metal contamination in industrial and urban surface dust (SD) poses significant risks to both human health and ecological systems. Hence, it is essential to identify and quantify the sources of pollution to support improved surface dust and soil management strategies. In this study, 22 surface dust samples were collected from the Bhiwadi Industrial Cluster (BIC) to evaluate total metal concentration, their pollution levels and remediation of metal form surface dust through soil washing technique by using various soil organic and inorganic agents. In the soil washing technique, the removal of metals was studied by using organic acids (OA) like acetic acid (AA), citric acid (CA), malonic acid (MA), sodium citrate (SC) salt, ethylenediaminetetraacetic acid (EDTA) and combining organic acids (AA+CA+MA) assisted with the ultrasonic process. For investigating removal efficiency, OA and SC salt were employed at 0.2 M concentrations, whereas EDTA and a combination of OAs were used at 0.1 M concentrations. Results showed that the average concentrations of Cd, Cr, Cu, Fe, Mn, Ni, Pb, V, and Zn in surface dust samples were 44.4, 172, 40, 3.6, 11, 10, 29, 2, and 17.7 times higher than their respective background values in the Upper Continental Crust (UCC). SD samples showed none to very strong contamination (Contamination Factor: CF >> 6) and the Pollution Load Index (PLI) exceeded unity, indicating a deterioration of soil quality. Geo-accumulation index in SD samples was in extremely high contaminated category for Cd, Cr, Cu, Mn, Ni, Pb and Zn and in the moderate category for Fe and V. The soil washing results suggested that a significant amount of metal can be removed from contaminated soils through washing techniques. The average metal removal percentage ranged from 0.01 to 8% (V = 0.01% and Cd = 8%) in AA, 0.4 to 17.2% (Fe = 0.4% and Cd = 17.2%) in CA, 0.02 to 11.7% (Cr = 0.02% and Pb = 11.7%) in EDTA, 0.8 to 18.1% (Fe = 0.8% and Cd = 18.1%) in EDTA, 0.02 to 1.1% (Cr = 0.02% and Cu = 1.1%) in SC and 1.7 to 24.15% (Cr = 1.7% and Cd = 24.1%) in the combination of OAs. Combining washing agents can markedly increase the removal efficiency as compared to single OA and EDTA, except for Pb. Metals can be removed efficiently by increasing the washing agent concentration, contact time and ultrasonic assistance. Therefore, soil washing might be an effective technique for metal remediation in surface dust/soils before disposing in open areas.
How to cite: Verma, Dr. A.: Pollution Levels and Chemical Remediation of Metal-Contaminated Surface Dust Using Soil Washing Techniques , EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-1260, https://doi.org/10.5194/egusphere-egu26-1260, 2026.
Many historical copper and cobalt mining operations were abandoned before the implementation of modern mining and environmental regulations, leaving behind large volumes of unmanaged mine tailings with elevated metal concentrations in forms of spoil heaps. Today, these sites represent both a source of soil contamination and a potential secondary resource of critical and strategic raw materials.
This research explores the application of magnetic soil washing as an innovative strategy for the reclamation of these Cu–Co contaminated mine soils and tailings, while simultaneously exploring their potential revalorization within a circular economy framework. Soil washing is an ex-situ decontamination process based on concentrating pollutants into a smaller fraction of soil, leaving the matrix with a lower content of pollutants.
Particularly, the high-mountain Texeo copper–cobalt mine (Asturias, Spain) was studied as a representative example of such legacy mining facilities. The area hosts a sulphide-rich geological setting, where copper and cobalt mineralization is mainly associated with iron-bearing phases derived from hydrothermal processes.
Here, a systematic soil sampling campaign was first conducted to assess the spatial extent and intensity of metal contamination. After this preliminary campaign, two large samples from areas with high (>1500 ppm of Cu; > 230 ppm of Co) and low (>600 ppm of Cu; > 60 ppm of Co) concentrations were selected and gathered. Afterwards, laboratory-scale remediation tests were carried out using wet high-intensity magnetic separation (WHIMS) for two soil fractions: coarse-sandy (2000-500 µm) and silt/clays (<500 µm).
Magnetic soil washing was applied to these two particle-size fractions to assess the partitioning of Cu- and Co-bearing phases between magnetic and non-magnetic products. The process aims to concentrate metal-rich phases into a reduced volume, facilitating their potential recovery, while decreasing contaminant levels in the bulk soil material to support its reclamation. The results were also reinforced with a mineralogical analysis of samples through X-Ray Diffraction and SEM-BSE imagery.
Preliminary results reveal a pronounced preferential concentration of Cu and Co in the magnetic fractions, particularly within the fine-grained material, reflecting their strong association with iron-rich sulphide and oxide phases. The resulting non-magnetic products exhibit a marked reduction in metal content, supporting the technical feasibility of magnetic soil washing to decouple environmental risk from resource value. These findings position magnetic separation as a promising, non-chemical and potentially scalable remediation pathway capable of transforming contaminated mine spoil heaps from environmental burdens into strategic secondary resources.
How to cite: Boente, C., Salgado, L., R. Gallego, J. L., Menéndez-Aguado, J. M., Díaz, A. M., Romero-García, S. A., Sánchez-Palencia, Y., and Ortiz, J. E.: Decontamination and revalorization of Cu–Co polluted mine spoil heaps through magnetic soil washing, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-3331, https://doi.org/10.5194/egusphere-egu26-3331, 2026.
Posters on site: Thu, 7 May, 08:30–10:15 | Hall X3
Groundwater in many industrial regions is highly contaminated with heavy metals such as zinc (Zn) and cadmium (Cd), posing risks to ecosystems and human health. Therefore, we tested a surface flow constructed wetland planted with reed canary grass (Phalaris arundinacea L.) as a remediation strategy. The selection of plant species is critical for achieving continuous metal removal from constructed wetlands. Most Cd and Zn accumulating plants reported in the literature do not grow under permanent flooding, are invasive, or do not tolerate the climatic conditions in Germany. P. arundinacea is one of the highest-yielding cool-season grasses characterized by a high translocation ratio of Cd and Zn. However, information on metal tolerance and removal from highly mineralized waters under field conditions is lacking in the literature. P. arundinacea cv. Lipaula was cultivated in intermediate bulk containers (IBCs) filled with a sand-and-gravel substrate (~730 individuals per square meter). Groundwater with high concentrations of zinc (300 mg/L), cadmium (4.5 mg/L), and sulphate (1500 mg/L) was supplied from experimental wells near the study site in Duisburg, Germany. Over two consecutive phases of 7 and 6 weeks, the IBCs were irrigated either with uncontaminated tap water (reference) or with groundwater diluted with tap water—ranging from 1:30 and 1:15 in the first phase to 1:1 and undiluted groundwater in the second. Each treatment was threefold replicated. Treatment effects were evaluated by morphometric plant parameters as well as fresh and dry biomass (FM, DM) and by analysis of Zn and Cd in plant tissue (ICP-MS). Moreover, element retention in the substrate was evaluated by NH4NO3 extracts. Plants treated with undiluted groundwater developed slight chlorosis but produced more biomass, with tendencies toward increased shoot (1550 ± 200 g/m²) and root (1600 ± 150 g/m²) dry mass and longer root systems. The plant contained up to 2529 mg/kg Zn and 17.6 mg/kg Cd (DM) in the shoots and up to 3778 mg/kg Zn and 68.8 mg/kg Cd (DM) in the roots. Considering total metal uptake (metal concentration × dry biomass), this corresponds to a potential removal of 33 kg Zn/ha and 215 g Cd/ha via the aboveground biomass over the entire 13-week growth period. Our findings demonstrated that P. arundinacea tolerates high levels of heavy metals and represents a promising phytoremediation plant species for heavy metal removal in constructed wetlands.
How to cite: Hinrichs, C., Arnstadt, T., Daum, D., and Wiche, O.: Phalaris arundinacea as a promising phytoremediation candidate for the removal of zinc and cadmium in surface flow constructed wetlands , EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-1757, https://doi.org/10.5194/egusphere-egu26-1757, 2026.
In highly metal-contaminated soils, the application of phytoremediation techniques is often constrained by the limited number of suitable plant species that can tolerate the adverse conditions. To overcome these limitations, plant growth is often supported by the application of growth-promoting rhizosphere bacteria (PGPR) and biochar. Still, information on the effects of combined biochar and PGPR applications on soil metal availability and plant responses beyond the most profoundly studied accumulator species is very scarce. In a greenhouse experiment, we cultivated the commercially available bioenergy grasses Phalaris arundinacea and Festuca arundinacea on soil contaminated with four concentrations of Zn, Cd, Cu, and Pb, in the absence or presence of Bacillus subtilis and biochar in the growth substrate (quartz sand). In the highest metal treatment, the plants received 1000 mg/kg Zn, 6 mg/kg Pb, 5 mg/kg Cu, and 0.5 mg/kg Cd in readily plant-available forms. The other metal treatments accounted for 50%, 25%, and 0% (reference) of the highest concentrations. Within each concentration level, the soil was either left untreated (reference) or additionally treated with Bacillus subtilis, 10% biochar or a combination of B. subtilis and biochar. Each treatment was fourfold replicated. After 5 weeks of plant growth, morphometric plant parameters of roots and shoots were measured. The rhizosphere soil was characterized regarding available element fractions and B. subtilis cell density. Root and shoot accumulation of elements was evaluated by ICP-MS. When metal treatment was low, the application of biochar and B. subtilis had no significant effect on plant growth. However, when exposed to high metal concentrations, plants treated with B. subtilis showed more than 60% higher biomass, irrespective of plant species. In contrast, the application of biochar and the combined treatment with biochar and B. subtilis had no significant effects on plant development. Preliminary results on root and shoot element concentrations indicated that B. subtilis did not influence net shoot and root uptake of elements. Ongoing analysis will elucidate the processes involved. We conclude that the application of B. subtilis is a promising strategy for enhanced plant tolerance and phytoremediation efficiency on highly polluted soils. We cannot rule out that combinations of B. subtilis with biochar might have synergistic effects when other soils and plant species are considered. Nonetheless, our data show that these combinations do not enhance phytoremediation per se when the plants are exposed to high metal concentrations in the growth medium.
How to cite: Wiche, O., Hinrichs, C. H., Samarska, A. S., Neumann, D., and Arnstadt, T.: Effects of biochar and root inoculation with Bacillus subtilis on plant growth and phytoremediation efficiency of Phalaris arundinacea and Festuca arundinacea in highly zinc and cadmium-polluted soils , EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-1827, https://doi.org/10.5194/egusphere-egu26-1827, 2026.
Soil, particularly in agricultural areas, may be impacted by military operations, nowadays even in Europe. An example is Ukraine which is also an important exporter of agricultural products and thus contributes to providing food for the world population.
Here we present results of an international project aimed at the monitoring of the state of agricultural land in Ukraine affected by military operations. Samples from 15 different locations were analyzed for the basic characterization of the soil organic matter. Content of the oxidizable carbon and the ratio of humic and fulvic acids were determined. Further, soil samples were subjected to thermogravimetric and infrared spectroscopy measurements. Quality or stability of soil organic matter was addressed using the respirometric technique as suggested by Kolář at al. [1, 2]. The results were compared with corresponding data from monitoring of Czech agricultural soils.
References
1. Kolář L., Klimeš F., Ledvina R., Kužel S. A method to determine mineralization kinetics of a decomposable part of soil organic matter in the soil. Plant Soil Environ. 49(1), 8-11 (2003).
2. Kolář L., Ledvina R., Kužel S., Klimeš F., Štindl P. Soil Organic Matter and its Stability in Aerobic and Anaerobic Conditions. Soil & Water Res. 1(2), 57-64 (2006).
Acknowledgement
This work was supported by The NATO Science for Peace and Security Programme, project Nr. G6296. https://land-security.org/.
How to cite: Pekař, M., Enev, V., Kalina, M., Klučáková, M., Širůček, D., and Závodská, P.: Soil and military operations, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-3723, https://doi.org/10.5194/egusphere-egu26-3723, 2026.
This study was conducted at a brownfield site in Carterville, Illinois, USA that was once an Illinois Ordnance Plant during World War II. The site was used for United States Army offices and ammunition manufacturing. After World War II, the site was turned over to Southern Illinois University to be used for vocational education and as a coal research facility. Over time, this location has experienced anthropogenic processes which have led to negative effects on the soil, including possible trace element contamination. According to US Soil Taxonomy, about 89% of the soils at the site are Epiaqualfs and Albaqualfs (Haplic Stagnosols and Planosols (Albic) in the World Reference Base (WRB)) while the other 11% are Hapludalfs and Fragiudalfs (Luvisols and Luvisols (Fragic) in WRB). This study was designed to examine the soils at the brownfield site for As, Cd, Cr, Cu, Hg, Ni, Pb, Sb, and Zn to determine whether they present human or environmental health concerns. Samples were collected with a hand probe from 130 locations at four depths (0-10, 10-20, 20-40, and 40-75 cm) in a grid. For part of the site, samples were collected at a density of 1.6 per ha, while the rest of the site was collected at 0.4 samples per ha. Air dried and ground (< 2 mm) samples were then scanned for 60 s each using an Evident Scientific Vanta Max portable X-ray fluorescence (PXRF) analyzer. Initial trace element pollution concerns were evaluated using the United States Environmental Protection Agency (EPA) Regional Screening Levels. Geographic information system interpolation maps were created to identify possible trace element hot spots. Using the screening levels, the majority of the trace elements analyzed are below the level of concern. However, As levels are higher than the EPA regulatory levels across the entire site. Cr levels exceed screening levels for Cr VI but are lower than allowed limits for Cr III. However, the PXRF does not allow for Cr speciation, so it is currently not known if Cr represents a concern. These results show that levels of As and Cr are a potential concern across the Carterville brownfield site due to anthropogenic pollution. Future research will investigate pollution indices to further codify potential negative human and environmental health impacts due to contamination at the site.
How to cite: Howell, C., Brevik, E. C., Weindorf, D. C., Indorante, S., and Weidhuner, A.: Trace Element Distribution at a Brownfield Site in Southern Illinois, USA, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-4117, https://doi.org/10.5194/egusphere-egu26-4117, 2026.
Two biochar-based adsorbents, namely original corn cob biochar (BC) and attapulgite (ATTP)-biochar composite (BA), were prepared via two-step pyrolysis at 400℃ and 700℃ under oxygen deficiency for petroleum hydrocarbons removal from water. Experimental results revealed that attapulgite modified the structure of biochar, increased the quantity of surface functional groups, and thereby significantly enhancing its adsorption capacity. Petroleum hydrocarbon adsorption experiments showed that adsorption kinetics was more accurately characterized by the pseudo-second-order model, and isothermal adsorption by the Freundlich model, supported by R2 and error analysis. This finding suggested that chemisorption through multi-molecular layers was the predominant mechanism of adsorption. Regarding the effect of pH, BC exhibited the maximum adsorption capacity under weakly acidic conditions (pH=5.0), while BA achieved optimal adsorption performance in neutral to weakly alkaline environments (pH=7.0-9.0), and BA exhibited an adsorption rate 41.8% higher than that of BC. In terms of salinity, it exerted a notable influence on the adsorption capacity of biochar; however, BA demonstrated superior adaptability over a wider salinity range (0.5% to 8.0%), and a 65.14% increase in overall adsorption efficiency compared to BC. Gas chromatography-mass spectrometry (GC-MS) and Fourier transform infrared spectroscopy (FTIR) indicated that the adsorption mechanism primarily encompassed surface adsorption, interfacial adsorption, micropore filling, hydrogen bonding, π-π bond interactions, and chelation effects. Additionally, specific redox reactions might have occurred alongside the adsorption process. In conclusion, this low-cost, environmentally friendly, and highly efficient carbon material held considerable promise for the removal of oil pollutants in saline-alkali environments.
How to cite: Wu, Y., Shao, Y., Wang, W., and Yuan, L.: Enhancement of petroleum hydrocarbon adsorption performance by attapulgite modified biochar: Performance and mechanism analysis, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-4954, https://doi.org/10.5194/egusphere-egu26-4954, 2026.
The Almadén area (Ciudad Real, Spain) is one of the world’s most important historic mercury mining districts, where centuries of extraction and processing have generated a persistent environmental legacy. Owing to its high toxicity, volatility, and long residence time in the environment, mercury remains a critical contaminant, particularly with respect to its mobility in soils and its transfer to biota and the human food chain.
In this context, the investigation of mercury and other potentially toxic elements in edible plant species is of particular relevance, as it provides insight into metal uptake mechanisms, bioaccumulation processes, and the potential environmental and health risks associated with plant consumption. Edible plants can act as effective bioindicators of soil contamination, offering valuable information on metal mobility, bioavailability, and exposure pathways affecting both ecosystems and human populations.
The main objective of this study is to assess the concentrations and distribution of mercury and other potentially toxic elements in edible plants from the Almadén area and to examine their relationships with soil physicochemical properties, in order to elucidate metal transfer processes within the soil–plant–atmosphere system, with special emphasis on Hg. Representative soil and plant samples are jointly analyzed, allowing comparisons among different plant species and sampling locations and enabling the identification of key factors controlling metal accumulation.
The results provide a robust basis for evaluating the risks associated with metal contamination in edible plants, identifying areas of increased environmental impact, and improving the environmental characterization of one of the most significant historic mining regions worldwide. In addition, this study contributes to the identification of plant species with a high capacity for metal accumulation, supporting the development of future strategies for environmental management, phytoextraction, and phytoremediation in contaminated soils.
How to cite: García-Donas Castillo, N., Barquero, J. I., Higueras, P., Jaeger, J., Avalos, O., Mbomio, F., and García-Donas, A.: Accumulation of Mercury and Other Potentially Toxic Elements in Edible Plants Associated with Soil Contamination in Historic Mining Areas, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-5852, https://doi.org/10.5194/egusphere-egu26-5852, 2026.
Polyfluoroalkyl Substances (PFAS) is a general class of organic compounds used for various industrial and household purposes including as a fire retardant. Because of their extreme structural stability under various conditions, PFAS compounds are known to persist in the environment causing toxicity to higher animals including humans. Both US EPA and EU set the maximum contaminant levels of PFAS in water ranging from 10-100 ppt. Soil is an important source and sink for PFAS compounds and adsorption is known to be an important process regulating the fate of these compounds. Thus, it is important to evaluate adsorption mechanisms of PFAS compounds on soil. Although various research studies focused on PFAS adsorption on soil, the application of detailed spectroscopic probes to isolate the mechanisms is rare. Here we propose to examine adsorption mechanism of selected PFAS compounds (PFOS: Perfluorooctanesulfonic acid and PFOA: Perfluorooctanoic acid) on a Tennessee native soil, Loring silt loam (Oxyaquic Fragiudalfs) using in situ attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopic probes under various solution properties. Since soil mineralogy plays a dominant role in surface interactions with organic molecules, PFOS and PFOA adsorption mechanisms on kaolinite, an important mineral in Loring silt loam, have been studied as well. Our initial findings suggested that PFOS makes an outer-sphere surface complex with Loring silt loam at pH 5 and ionic strength of 0.01 M NaCl. When inorganic P (Pi) was added, infrared (IR) bands relevant to PFOS adsorption decreased and some evidence of IR bands pertaining to Pi appeared, thereby corroborating outer-sphere adsorption. Adsorption of POFA on Loring soil indicated a similar outcome. Our results will help understand the mechanisms of biogeochemical cycles of PFAS compounds in the soil environment.
How to cite: Rakshit, S., Blankenship, D., and Reddy, C.: Biogeochemical Cycling of Selected PFAS Compounds in Tennessee Loring Silt Loam, Insights from in situ-ATR-FTIR Probes, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-7981, https://doi.org/10.5194/egusphere-egu26-7981, 2026.
Biochar is a carbon material that can be produced from renewable biomass and has been primarily used in soil remediation and regarded as a functional carbon material due to its cost-effective and environmentally friendly characteristics. Aside from the primary aim of pollution remediation, biochar in this study was prepared using the invasive plant Leucaena leucocephala to achieve the forest conservation goal. Biochar was sequentially modified by acid washing followed by iron loading. The textural properties were enhanced, raising the BET surface area from 68 to 102 m2/g and improving pore volume 266%. Magnetically iron-modified biochar (Fe-ATB) achieved efficient phosphate recovery, exhibiting a 17-fold increase in binding affinity over pristine biochar. Magnetite formation (∼31% Fe oxide) enabled high magnetic recovery efficiencies in both aqueous (96.0%) and soil (91.2%) systems, supporting its economic viability for reusable adsorption cycles. Further research will be conducted on an emerging contaminant, Ibuprofen (IBP), using green waste from mixed wood as the source of biochar, adopting a more sustainable approach. To enhance IBP adsorption and degradation, additional modification of microbe loading will be applied to Fe-ATB. Out of 27 bacterial strains tested, six strains including Cellulosimicrobium funkei, Promicromonospora thailandica, Serratia marcescens, Bacillus aryabhattai, Sphingorhabdus buctiana, and Gordonia terrae exhibited high IBP tolerance up to 500 mg kg-1. Therefore, applying iron-modified and microbe-loaded biochar is expected to improve IBP degradation, adsorption, and overall removal efficiency in IBP-contaminated soil and water, while facilitating magnetic separation and circular utilization, thereby contributing to sustainable remediation strategies.
How to cite: Jien, S.-H. and Maisyarah, S.: Engineering Iron–Microbe Interfaces on Biochar to Regulate Phosphate Fixation and Ibuprofen Retention across Soil–Water Continua, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-9052, https://doi.org/10.5194/egusphere-egu26-9052, 2026.
Anaerobic paddy soils are a major source of methane (CH4) emissions. When the soil is contaminated with arsenic (As), the reducing environments favor the predominance of the highly mobile and toxic As(III). This indicates that flooded paddy soils can simultaneously pose risks associated with greenhouse gas emissions and As toxicity. Sulfate-reducing bacteria (SRB) compete with methanogens for electron donors, while the sulfide produced during sulfate reduction can react with As to form stable As-sulfide phases. Therefore, this study aimed to evaluate the simultaneous mitigation of CH4 emissions and immobilization of As in paddy soils by applying sulfate-based amendments, including ammonium sulfate (NS), iron sulfate (FS), or potassium sulfate (KS). Ten grams of soil were treated with 0.3% NS, FS or KS, with untreated soil used as a control. The soil was amended with either 30 mL of 1000 mg/L deionized water or As(V) solution, and incubated under N2-purged anaerobic conditions at 25°C in the dark. Greenhouse gas emissions were monitored and As concentration and speciation in soil solution were analyzed. Ammonium sulfate, FS, and KS reduced CH4 emissions by 95.6%, 81.4%, and 94.2%, respectively, compared with the control under deionized water conditions, while under As solution conditions, CH4 reduction reached 100% for NS and KS, and 21.3% for FS. At the same time, total As immobilization increased by 26.9%, 31.2%, and 7.23% compared with the control, and the reduction of As(V) to As(III) was suppressed by 55.0%, 19.3%, and 100% in the NS, FS, and KS treatments, respectively. Iron sulfate was less effective at CH4 mitigation than NS and KS because Fe acted as an additional electron donor, enhancing methanogenesis. In addition, FS induced the strongest reduction of As(V) to As(III) through active Fe redox reactions, but showed the highest total As immobilization. Dehydrogenase activity followed the order NS > FS > KS under both deionized water and As solution conditions, likely because NS supplies both sulfate and readily available nitrogen, strongly stimulating microbial metabolic activity. Overall, sulfate-based amendments effectively suppressed CH4 emissions and enhanced As immobilization in paddy soils by stimulating SRB-driven processes. These results indicate that sulfate-based amendments represent a promising strategy for simultaneously mitigating greenhouse gas emissions and As risks in rice paddy systems.
Acknowledgments
This research was supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (RS-2024-00414790).
How to cite: Kim, H. and Park, J. H.: Stimulating sulfate reducing bacteria by sulfate-based amendments to reduce methane emissions and immobilize arsenic in paddy soils, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-10550, https://doi.org/10.5194/egusphere-egu26-10550, 2026.
The UN, through the FAO and UNEP, emphasizes that soil health is vital for food production, with 95% of food deriving from soil. However, one-third of global soils are already degraded, posing a threat to food security and nutrition. Emerging contaminants, such as pharmaceutical products (PPs), are now continuously detected in water, soils, food, animals, and plants. Their increasing presence in agricultural soils is of particular concern. Nevertheless, scientific evidence regarding the ecotoxicity of PPs and their impact on soil ecosystem functions—processes in which soil microbiota play a crucial role—remains scarce. This study aimed to determine and evaluate the toxic effects of four pharmaceuticals—the antiseptic chlorhexidine, the antibiotic sulfadimethoxine, the anticonvulsant sodium valproate, and the steroidal anti-inflammatory prednisolone—on soil microbiological activity using standard ecotoxicity tests. The experiment included the following assays: OECD TG 216 (Soil Microorganisms: Nitrogen Transformation Test); OECD TG 217 (Soil Microorganisms: Carbon Transformation Test); and ISO 18187:2018 (Soil quality – Contact test for solid samples using the dehydrogenase activity of Arthrobacter globiformis). The results indicated that, at the tested doses, these PPs did not significantly reduce the overall microbiological activity of the reference soil, suggesting an EC50 greater than 100 mg kg⁻¹ for these compounds. Soil nitrifying activity was highly variable; however, sulfadimethoxine was the only compound found to inhibit nitrification after 28 days of incubation. In contrast, chlorhexidine exhibited a clear toxic effect on the dehydrogenase activity of A. globiformis. This finding implies that environmental consequences could be significant if chlorhexidine is present at relatively high concentrations in soils. Our results suggest that natural biodegradation by soil microorganisms is key to mitigating the toxic effects of the studied pharmaceuticals. Further research is necessary to investigate potential cumulative, synergistic, and long-term environmental impacts.
How to cite: Alejos-Campo, A., Fernéndez-Gómez, E., Rentería, R., Roca-Pérez, L., Mercado, B., Andreu, O., and Boluda, R.: Ecotoxicity of Selected Pharmaceuticals and Their Effects on Soil Microbiota, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-11836, https://doi.org/10.5194/egusphere-egu26-11836, 2026.
Urban soils often retain heavy metal contamination from historical industrial activity, leading to long-term degradation of soil and water quality. Conventional remediation approaches, including physical removal and chelate-assisted phytoextraction, are often expensive, disruptive, and limited in their capacity to restore ecological function. This research investigates the potential of co-planted systems to enhance both contaminant removal via phytoextraction and ecological recovery. Greenhouse and in-situ trials employing four hyperaccumulator species (Helianthus annus, Zea mays, Trifolium pratense, Lolium perenne) compare co-planted assemblages with monocultures to assess effects on plant growth, heavy metal uptake, and soil chemistry. Salix viminalis was also included as a companion plant due to previous evidence of woody species facilitating growth and heavy metal uptake. By examining differences in growth rates, plant tissue heavy metal concentration and root exudate composition between monocultures and co-planting treatments the project seeks to identify synergistic mechanisms that promote effective remediation while supporting ecosystem resilience.
Early greenhouse trials have demonstrated that heavy metal uptake (figure 1), soil acidity and total organic carbon (TOC) of root exudates can be increased in co-planted treatments. For example, non-purgeable organic carbon (NPOC) increased in Helianthus annus root exudates from 2ppm to 7ppm when planted with Salix viminalis. However, the differences are not universal; introducing Lolium perenne increased Ni uptake for plots with Zea mays (0.011mg/kg/day to 0.057mg/kg/day), whereas it inhibited Ni uptake for Helianthus annus (0.81mg/kg/day to 0.21mg/kg/day). As root exudates are often composed of organic and amino acids, they have potential to significantly affect both the soil microbiome and heavy metal mobility. Therefore, ongoing investigations will observe the plant physiological mechanisms affecting heavy metal mobility in soils, by identifying key metabolites in root exudate samples and their release in co-planted treatments versus monocultures.
Ultimately, this work demonstrates how diverse planting strategies can improve heavy metal uptake of remediator species whilst increasing soil nutrient content and enhancing ecosystem multifunctionality. The findings thus far have indicated a complex network of plant-plant and plant-soil interactions with practical implications for scalable, low-cost land management practices in urban areas – For instance, pairing Zea mays with Lolium perenne and woody species in marginal industrial areas, to increase Ni uptake and soil carbon.
Figure 1 – Results from preliminary ICP-OES detection for Nickel concentration in leaf material of Zea maize when cultivated in monocultures, compared to co-planted with Helianthus annus or Lolium perenne. Units are mg/kg/day to show rate of nickel accumulation over time.
How to cite: Basi, A., Hamilton, L., and Batty, L.: Urban legacy pollution: Novel techniques for phytoremediation of marginal brownfield sites, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-13500, https://doi.org/10.5194/egusphere-egu26-13500, 2026.
Heavy metals (HMs) contamination in agricultural soil interferes with vital plant physiological processes, significantly constraining the growth of medicinal plant Pseudostellaria heterophylla (P. heterophylla). To mitigate HMs stress, Sedum alfredii (S. alfredii) has been applied as an efficient hyperaccumulator for phytoremediation. However, intercropping S. alfredii with P. heterophylla and the associated soil hydrochemical properties responses remain largely unknown. This study aims to mitigate the stress of HMs, i.e., Lead, Cadmium and Copper, in the contaminated soil by intercropping S. alfredii and P. heterophylla. The growth of P. heterophylla will be evaluated with leaf and root development, and HMs removal efficiency will be analysed with the concentrations of HMs in plant tissues and residual soil. Additionally, soil hydrochemical properties will be measured. This study will elucidate how intercropping S.alfredii and P. heterophylla influences soil HMs bioavailability by affecting soil hydrochemical properties. A clear and detailed description of the experiment and measurements will be provided, and the results will be carefully analysed to identify key findings, explain underlying mechanisms, and highlight new insights.
The authors would like to acknowledge the financial support provided by the State Key Laboratory of Climate Resilience for Coastal Cities (ITC-SKLCRCC26EG01) and the Research Grants Council of HKSAR (C5033-23G).
How to cite: Pi, Z., Yan, W., and Ng, C. W. W.: Intercropping Sedum alfredii and Pseudostellaria heterophylla to mitigate heavy metal stress in contaminated soil, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-15856, https://doi.org/10.5194/egusphere-egu26-15856, 2026.
Tin mining activities in Bangka Regency, Indonesia have left behind severely degraded landscapes characterized by low nutrient availability and heavy metal contamination. Despite these constraints, post-mining soil has the potential for conversion into productive agricultural areas that could contributes to local food security. The utilization of post-mining soils for crop production such as leafy vegetables (spinach), can be achieved through the use of soil amendments that can improve soil fertility and bind heavy metals. The present study investigated the effects of rice husk biochar and compost amendments on soil properties, plant growth, and heavy metal uptake in spinach (Amaranthus sp.) through a pot experiment using various amendment doses. Soil parameters analyzed included pH, total nitrogen (N), available phosphorus (P), exchangeable potassium (K), organic carbon (C), lead (Pb), and cadmium (Cd). Plant responses were assessed based on plant height, fresh biomass, leaf area, SPAD chlorophyll index, and Pb concentration in leaves. The results indicated that the combined application of compost and biochar significantly increased soil pH, total N, and organic C. This treatment also markedly improved spinach growth, as indicated by greater plant height and fresh biomass yield. Biochar application alone was more effective in reducing heavy metal concentrations in soil, while the combined application of biochar and compost was more effective in decreasing Pb accumulation in spinach leaves. These findings highlight the potential of integrated biochar and compost as strategy for improving soil health and mitigating heavy metal risks in post-tin mining soils.
How to cite: Pitaloka, N. D., Maftukhah, R., Rahmawati, F., Arundanti, S. A., Wahyuni, T., Ngadisih, N., Wulandari, C., and Keiblinger, K. M.: Evaluating Post-Tin Mining Soil Regeneration and Heavy Metal Immobilization in Spinach (Amaranthus sp.) Using Biochar and Compost as Soil Amendments, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-16187, https://doi.org/10.5194/egusphere-egu26-16187, 2026.
Post-tin mining soils are highly degraded environments that often contained elevated concentrations of potentially toxic elements, posing persistent risks to food safety when reused for agriculture. This four-year field experiment evaluates whether soil amendment strategies can promote soil regeneration while reducing heavy metal transfer to major staple crop, cassava (Manihot esculenta Crantz). Six treatments were established in an intercropped plot system with legume species: control (no amendment), dolomite, compost, charcoal, charcoal + compost, and charcoal + sawdust. Temporal changes in soil pH and soil organic carbon (SOC) were monitored as key indicators of soil recovery. Cassava yield was measured, and Pb, Cd, and As concentrations in cassava edible part were analysed to trace the temporal changes in heavy metal uptake. All amended treatments showed progressive increases in soil pH and SOC over the four-year period, indicating gradual recovery of soil chemical quality of post-tin mining soils. Cassava yield increased accordingly, with the charcoal + compost treatment consistently producing the highest yields. From a food safety perspective, Pb, Cd, and As concentrations in cassava tissues exhibited a clean declining trend all treatments through time, demonstrating a temporal reduction in metal bioavailability and plant uptake. The strongest decreases in tissue metal concentrations were associated with treatments that most effectively increased SOC and stabilized soil pH. This long-term case study demonstrates that targeted soil rehabilitation strategies can mitigate contamination risks while restoring agricultural function to post-mining soils. Tracing soil regeneration alongside temporal patterns of plant tissue contamination provides a robust framework for evaluating the food safety of mining-impacted lands and supports sustainable land management.
How to cite: Maftukhah, R., Mentler, A., Pitaloka, N. D., Ngadisih, N., Murtiningrum, M., Hood-Nowotny, R., and Keiblinger, K.: Temporal Dynamics of Heavy Metal Uptake and Food Safety Risk in Cassava Grown on Rehabilitated Post-Tin Mining Soils, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-17404, https://doi.org/10.5194/egusphere-egu26-17404, 2026.
The presence of non-essential metals threatens agricultural productivity and food safety in many regions of Europe, particularly where historical contamination coexists with ongoing land use. Gentle remediation options, such as soil amendments coupled with appropriate vegetation, offer cost-effective and environmentally compatible means to reduce metal mobility and exposure risk, while restoring safe, productive use on contaminated land. Within this context, this study investigated a historically metal-impacted field in Arnoldstein (Carinthia, Austria) to assess amendment-driven immobilization and its persistence over time.
Arnoldstein has a long history of Pb-Zn mining and smelting dating back to the 15th century. Despite the smelter’s closure in 1992, elevated Cd, Pb and Zn concentrations remain in the topsoil in the surrounding area, exceeding national assessment values for agricultural and horticultural use and constraining safe biomass production.
Building on prior studies that tested various amendments, a field experiment was established in Arnoldstein in 2013-2014 to compare an organic (poplar N-enriched biochar, P-BC), a mineral amendment (gravel sludge plus iron oxide, GSFe), and their combination (P-BC + GSFe) for aided phytostabilisation using Miscanthus x giganteus. Amendments were applied at a rate of 1% (w/w) to a depth of 10 cm. Across treatments, NH4NO3-extractable Cd, Zn and Pb in the amended topsoil were significantly reduced relative to control. Metal concentrations in miscanthus shoots remained low and were largely unaffected by treatment, indicating limited translocation despite improved immobilization in soil.
Within the Interreg project “PoLaRecCE”, the site was revisited in autumn 2024, after a decade without active management, to evaluate the long-term performance of the soil amendments. Resampling showed that reduced bioavailability of Cd, Zn and Pb persisted, demonstrating durable field-scale immobilization beyond short-term effects under real field conditions without intensive management. The current phase extends the assessment to soil health indicators to evaluate broader functional recovery.
How to cite: Hartmann, F., Brumen, F., Soja, G., Rechberger, M., Radke, M., Jedlaucnik, V., and Puschenreiter, M.: Long-term efficiency of metal immobilization by soil amendments in a metal contaminated area in Austria, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-17884, https://doi.org/10.5194/egusphere-egu26-17884, 2026.
The mining industry constitutes a fundamental pillar of modern society and has gained increasing strategic relevance in the current geopolitical context. The growing demand for critical raw materials should not be limited to the exploration of new geological deposits, but should also incorporate alternative and innovative approaches such as urban mining, recycling, and waste valorisation.
Traditionally, mining wastes have been accumulated in waste dumps, often with a primary focus on ensuring geotechnical stability, while environmental restoration efforts have largely been limited to geomorphological reshaping and visual landscape mitigation. However, many waste dumps contain elements currently classified as critical raw materials, which frequently co-occur with contaminants due to their inherent toxicity.
In this context, the duality between the valorization of mining wastes for the recovery of critical raw materials and the mitigation of their potential environmental impacts through restoration techniques becomes particularly relevant. This study presents several case studies that integrate the reprocessing of mining waste dumps for the recovery of valuable elements, as well as the valorisation of mining wastes as soil amendments, with restoration strategies based on phytoremediation and the application of organic and inorganic amendments, including carbon foams, biochar, and nanomaterials.
The results highlight the importance of adopting a holistic approach to mining waste management, in which environmental restoration and critical raw material recovery are addressed simultaneously as part of a sustainable strategy aligned with the principles of the circular economy.
How to cite: Baragaño, D., Salgado, B., Sánchez, S., Ratié, G., Berrezueta, E., Arranz, J. C., Fernández, J., and López-Antón, M. A.: The duality between critical raw material recovery and the restoration of mining waste dumps, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-18754, https://doi.org/10.5194/egusphere-egu26-18754, 2026.
Land degradation is a major environmental challenge in post-mining landscapes, where soil structure, fertility, carbon storage and potentially hazardous elements availability are severely compromised. Designed Technosols have emerged as a promising strategy for restoring soil functionality in such disturbed areas under different climatic conditions. Their effectiveness under field conditions over time requires systematic evaluation but these studies are scarce. A study was conducted at the São Domingos mine (Iberian Pyrite Belt, Portugal), where the first pilot project using designed Technosols for environmental rehabilitation was implemented in late 2020 (1.5 ha).
From the rehabilitation implementation system, physicochemical characteristics of Technosol and vegetation development have been monitored to understand the underlying temporal dynamics. Additionally, to physicochemical analysis in the soil samples collected periodically, the evolution of the temporal change was assessed via remote sensing for the area. Adjacent areas without Technosol application were used as control.
In general, mine areas without Technosol maintain their high environmental risk due to acid characteristics and high availability of potentially hazardous elements-PHE. Technosol remains their eutrophic and alkaline properties, supporting dense vegetation cover and improvement chemical characteristics of the area (pH, fertility and diminution of PHE spreading). Nonetheless temporal patterns following Technosol application have been observed.
For instance, Organic C and total N exhibited similar trends, with the highest values at implementation (130.58 g/kg and 7.92 g/kg, respectively), followed by a moderate decline over time, although it was statistically significant only after six months. C stock dynamics further supported these trends. Below-ground C stock increased gradually from (96.65 to 106.81 t C/ha) over 27 months and remained within the same overall range as the implementation, indicating high stabilization potential. Overall, Above-ground C stock increased from 11.55 to 108.85 t C/ha, peaking at 302.31 t C/ha after six months. Temporal evaluation using NDVI showed an increase in area and intensity of the index from 0.03 to 0.9. Overall, the grouped trends demonstrate that Technosols simultaneously promote biological activity, the improvement of C and N balance and enhance both below- and above-ground C stocks.
To evaluate the drivers of the rehabilitation system evolution, remote sensing products to derive topographic and hydrologic covariates (slope, aspect, topographic position, and connectivity proxies) are included to evaluate their influence on C stock, PHE availability and runoff connectivity in adjacent areas to the Technosol area. This study provides important indicators framework linking contamination dynamics and ecosystem recovery as well as the effectiveness of the environmental system with designed Technosol at long term.
This work was funded by national funds through FCT—Fundação para a Ciência e a Tecnologia under the projects UID/04129/2025 (LEAF) and LA/P/0092/2020 (TERRA).
How to cite: Benhalima, Y., Dadina, A., Pena, S., Abreu, M. M., S. Santos, E., and Arán, D.: Field evidence of environmental recovery after designed Technosol application in sulfide mine environment, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-20795, https://doi.org/10.5194/egusphere-egu26-20795, 2026.
Nickel agromining harnesses hyperaccumulator plants to recover critical metals from metal-rich soils, offering a low-impact alternative to conventional mining and a pathway for the valorisation of contaminated or marginal land. However, the economic viability of this approach remains constrained by limited nickel yield in aboveground biomass, motivating the development of strategies to enhance plant metal uptake. This study evaluated a broad range of agronomic strategies to enhance shoot Ni accumulation in the Ni hyperaccumulator Alyssum argenteum under controlled glasshouse conditions.
Plants were grown in a substrate spiked to 600 mg kg⁻¹ Ni and subjected to three categories of treatments applied independently: (i) the biodegradable chelating agent EDDS and a set of low-molecular-weight organic acids (citric, oxalic, malic, and acetic acids), (ii) plant growth regulators representing auxin (IAA, NAA), cytokinin (BAP) and gibberellin (GA) classes, and (iii) plant growth-promoting bacteria (Pseudomonas fluorescens, P. putida, P. protegens, and a consortium). At harvest, nickel yield was quantified as shoot Ni per plant (leaf + stem). In parallel, physiological and biochemical responses were assessed, including photosynthetic pigments (chlorophylls, carotenoids, and anthocyanins), histidine, hydrogen peroxide (H₂O₂), and reduced glutathione (GSH).
All three treatment classes produced substantial positive effects on shoot Ni yield. Among phytohormones, IAA and GA produced the strongest enhancements, with mean shoot Ni increases typically exceeding +50% vs control and, under the highest application levels, surpassing +100% vs control. The strongest overall responses were observed for the chemical amendments, with malic and oxalic acids, followed by citric acid and EDDS, frequently increasing shoot Ni by >+100% vs control, depending on dose. In the biological treatments, inoculation with P. putida and the consortium consistently enhanced shoot Ni yield, with increases of up to ~+50% vs control.
Enhanced shoot Ni accumulation was accompanied by treatment-specific changes in pigment composition, histidine concentrations, and redox markers (H₂O₂ and GSH), indicating that improved Ni yield was associated with modulation of photosynthetic performance, metal complexation, and oxidative stress responses rather than simple biomass effects. While more detailed statistical analyses are pending, these results demonstrate that targeted chemical and biological amendments can markedly enhance harvestable Ni yield in A. argenteum, providing a strong experimental basis for optimising nickel agromining systems
How to cite: Yin, Q. (., Carfrae, J., Graham, M., Ngwenya, B., and Novo, L.: Enhancing harvestable nickel yield in Alyssum argenteum through chemical, hormonal and biological amendments: implications for nickel agromining, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-22793, https://doi.org/10.5194/egusphere-egu26-22793, 2026.
Posters virtual: Wed, 6 May, 14:00–18:00 | vPoster spot 2
EGU26-294 | ECS | Posters virtual | VPS17
Potential of Radon Deficit as a Monitoring Tool in Organic Soil Remediation: A Machine Learning-Based Predictive ApproachWed, 06 May, 14:36–14:39 (CEST) vPoster spot 2
The characterization and monitoring of soils and groundwater affected by non-aqueous phase liquids (NAPLs) remains a challenge due to the difficulty and high costs associated with their spatial delineation through intrusive methods (e.g., core-recovery drilling). The radon deficit technique is a promising screening method that enables the identification of potentially impacted areas based on the ubiquity of this gas, its operational simplicity and capability for rapid in situ measurement, and its preferential partitioning into NAPLs. However, subsurface sampling does not allow discrimination between impacts occurring in the vadose zone and those in the saturated zone. This work proposes the application of machine learning algorithms (Random Forest) as a tool to analyze the spatial variability of radon activity data in contaminated sites, with the aim of quantitatively determining their dependence on information related to contamination processes in both the vadose and saturated zones, as well as evaluating the ability of these algorithms to assess the potential of the radon deficit technique for monitoring remediation processes in NAPL-impacted sites.
This study uses information collected during sampling campaigns conducted at a NAPL-impacted site at various depths within the vadose and saturated zones. The collected data (radon activity, lithological characteristics, and organic contamination information) were integrated into a machine learning algorithm that enabled the spatial analysis of the joint behavior of the variables, resulting in a predictive model to assess the potential of the radon deficit technique for monitoring remediation processes.
The results suggest that the radon deficit is a useful screening and monitoring method for NAPL-impacted sites, and demonstrate the value of machine learning not only as a predictive tool but also as an analytical resource to interpret complex relationships and validate indirect environmental monitoring techniques.
How to cite: Montalvo Piñeiro, J., Barrio Parra, F., Serrano García, H., Izquierdo Díaz, M., De Miguel García, E., and Lorenzo Fernández, D.: Potential of Radon Deficit as a Monitoring Tool in Organic Soil Remediation: A Machine Learning-Based Predictive Approach, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-294, https://doi.org/10.5194/egusphere-egu26-294, 2026.
EGU26-18654 | ECS | Posters virtual | VPS17
Soil and vegetation diversity responses to designed Technosol applied in a sulfide mine under semi-arid conditions: field evidence at long termWed, 06 May, 14:39–14:42 (CEST) vPoster spot 2
The recovery of sulfide mine areas using designed Technosols and vegetation is often evaluated under controlled conditions, whereas field-scale evidence remains scarce. The first pilot (1.5 ha) with designed Technosols, produced from agro-industrial and urban wastes, was installed at the São Domingos mine (Iberian Pyrite Belt, Portugal)in two areas subject to continuous leaching of acid mine drainage, for environmental recovery purpose. An adjacent area without Technosol was used as control. The areas with and without Technosol were sown with a commercial herbaceous mixture including some autochthonous shrub species. After 4.5 years from recovery system (Technosol+vegetation) installation, the physicochemical quality of soil (pH, EC, fertility, nutrients and potentially hazardous elements-PHE availability) and the vegetation status (species composition, % cover, total biomass, seed bank diversity) were evaluated. A total of 25 randomly distributed sampling points were established with both soil and vegetation samples collected at each point (T1-Technosol area: 15, T2-Technosol area 2: 5, control: 5). The aim of the study was to evaluate the chemical quality of soil and vegetation status in the Technosol and control areas at long-term.
The application of the designed Technosol significantly improved the soil quality of the mine area compared to the control, increasing pH (from 4.08 to 7.76) and organic C content (62.49 vs. 2.42 g kg⁻¹). The available fractions of macronutrients were higher in the Technosols areas while available PHE amounts were approximately 73% lower than in the control area. Vegetation reflected soil improvement, with 20 taxa (10 families) registered and higher family richness in the Technosol areas (10 vs. 4) .Technosols areas were dominated by Poaceae and Asteraceae showing almost complete soil cover (~96%). The control area was barely covered (<9%) mainly by Poaceae with Linaceae and Brassicaceae. The soil seed bank showed higher plant diversity in Technosols samples (8 families), while no germination was recorded in the control (assay conducted under controlled conditions for 3 months).
Comparing the two areas with Technosol, no remarkable differences was obtained for pH (7.75–7.78 and low PHE availability but EC EC (500.6 vs. 236.4 µS/cm), available P content (321.7 vs. 191.1 mg kg⁻¹) and CEC (61.1 vs. 46.6) were different. Despite the application of similar Technosol and seeding, the plant communities diverged for the plant diversity (8 families vs. 5) and dominance of grasses. Although the vegetation cover and biomass amounts were similar between the Technosol areas, a differentiation of the carbon stock obtained (948.8 vs. 645.2 g C/m-2). Seed bank family richness was similar (6 families each) but composition differed Poaceae, Asteraceae, Urticaceae and Apiaceae families were common, while presence of Brassicaceae and Solanaceae or Malvaceae and Amaranthaceae depended on the Technosol area. This field case study provides a practical workflow linking soil improvement, contamination dynamics and vegetation recovery. It highlights the effectiveness of Technosol in environmental recovery of sulfide mine areas at long term and the spatial heterogeneity evolution.
This work was funded by national funds through FCT—Fundação para a Ciência e a Tecnologia under the projects UID/04129/2025 (LEAF) and LA/P/0092/2020 (TERRA).
How to cite: Estrada, A., Benhalima, Y., Santos, E., and Arán, D.: Soil and vegetation diversity responses to designed Technosol applied in a sulfide mine under semi-arid conditions: field evidence at long term, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-18654, https://doi.org/10.5194/egusphere-egu26-18654, 2026.
EGU26-14632 | ECS | Posters virtual | VPS17
MIC/MBC resistance fingerprints to As(III) in Bacillus and Pseudomonas as bioindicators across water and solid matrices in southern PerúWed, 06 May, 14:48–14:51 (CEST) vPoster spot 2
Arsenic (As) contamination in soils and waters is a critical challenge to human health, agricultural productivity, and ecological integrity. In soil-water systems, As can modify microbial community structure and physicochemical properties; therefore, indicators that integrate As availability and biological stress across heterogeneous matrices are needed. This study evaluated whether phenotypic As resistance patterns in environmental bacteria can be used as bioindicators and whether native, As-tolerant Bacillus and Pseudomonas stains could support recovery-oriented assessments.
Soil/sediment and water samples were collected at six sites across three high-Andean areas in southern Perú: Desaguadero (Puno; deep well and spring), Sicuani (Cusco; two springs), and Espinar (Cusco; Salado River). Solid matrices included riverbed sediments, saturated solids at spring outlets, and excavated well soils (drill cuttings/spoil around the wellhead). In soil/sediment, pseudo-total As was determined by aqua regia digestion. In waters, dissolved As, was quantified alter filtration (0.45 µm) and acidification (HNO3 (pH < 2).
Tolerance assays were performed on nutrient agar amended with 100, 1000, 1500, and 2000 mg L-1 As (III) at 30°C for 24-72 h to estimate the minimum inhibitory concentration (MIC). The minimum bactericidal concentration (MBC) was then determined by subculture in As-free broth (triplicate; OD600). A total of 59 isolates were obtained: Bacillus (n = 40, water = 12, solid matrix = 28) and Pseudomonas (n = 19, water = 3, solid matrix = 16). Biochemical profiling assigned Bacillus to the B. cereus complex (cereus/thuringiensis), B. subtilis group, and Bacillus spp.; Pseudomonas to P. aeruginosa, P. stutzeri, P. mendocina and Pseudomonas spp.
Bacillus showed higher resistance than Pseudomonas: with growth observed in 37/40, 28/40, 20/40 and 4/40 isolates at 1000, 1500 and 2000 mg L-1, respectively, and higher tolerance enriched in solid matrix isolates (1500 mg L-1: 17/28 vs 3/12; 2000 mg L-1: 4/28 vs 0/12). In Pseudomonas, growth occurred in 16/19, 9/19 3/19 and 0/19 isolates at the same concentrations. The most tolerant isolates were B2539 (Bacillus sp.; MBC = 2200 mg L-1) and P2501 (P. aeruginosa), with an MBC = 1400 mg L-1). These results support MIC/MBC “resistance fingerprints” as quantitative bioindicators to compare sites and matrices in As-affected environments.
Keywords: arsenic; microbial bioindicators; riverbed sediment; springs, soil; Bacillus; Psedomonas; souther Perú.
How to cite: Cjuno Huanca, O. L., Valderrama Negrón, A. C., Quino Favero, J. M., and Silva Santos, E.: MIC/MBC resistance fingerprints to As(III) in Bacillus and Pseudomonas as bioindicators across water and solid matrices in southern Perú, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-14632, https://doi.org/10.5194/egusphere-egu26-14632, 2026.
EGU26-19332 | Posters virtual | VPS17
Changes in soil structure and sorption capacity after mixed treatment with macromolecular compounds and orange peels-derived activated carbonsWed, 06 May, 14:51–14:54 (CEST) vPoster spot 2
Soil provides 95% of our food and provides other essential ecosystem services, such as water purification, biodiversity, and climate regulation. Unfortunately, numerous agroecological functions of soil are increasingly threatened by the intensifying, primarily anthropogenic, processes of soil degradation. This deteriorates the surface, sorption, and buffering properties of soils, the spread of pollutants into watercourses and groundwater, and adverse changes in porosity, organic matter composition and content, wettability, aggregation, and microbial community, resulting in soil partially or completely losing its ability to function properly. Therefore, it is so important to develop new soil conditioners that can reduce the effects of anthropogenic pressure and make soils more resistant to negative phenomena.
The main aim of this study was to estimate the impact of newly developed biochars and activated carbons from orange peels as well as water-soluble polymers (exopolysaccharide of bacterial origin (Rhizobium leguminosarum bv. trifolii), ionic polyacrylamides) on the structure and sorption capacity of the selected soil. Haplic Luvisol, the most common Polish soil, was collected from 0–20 cm depth of arable land in Poland (Parchatka, Lublin Upland, N 51°22′54″ E 21°59′54″). It was derived from loess parent material. It was modified with 1 wt.% of solid modifier (biochar, or activated carbon) by mixing. Macromolecular compounds (of initial concentration 100 mg/L) were added in the form of solutions. The following parameters: pH, ash content, total organic carbon content, porosity, variable surface charge of the soil were measured before and after modification to estimate effectiveness of the performed treatment. The soil sorption capacity was examined towards copper (Cu) and cadmium (Cd) using a batch adsorption method. The metal concentration was determined using a atomic absorption spectrometer working in the graphite cuvette technique (ContrAA 800, Analytik Jena, Germany). Porosity of the soils was examined using a mercury porosimetry (autopore IV 9500, Micrometrics INC, USA).
It was observed that all modifications using carbonaceous materials improved total pore area, average pore diameter, and total porosity of the soil, which was mainly associated with highly porous structure and relatively large specific surface area of the applied solids. The modification with activated carbon and cationic polyacrylamide resulted in the highest increase in total pore area. Carbon-rich materials could not only increase specific surface area and porosity of the soil, but also form organo-mineral connections, improving the number of active centers. Consequently, they increase soil sorption capacity towards Cu and Cd. The activated carbon application improved their 3- and 1.9-fold adsorption, respectively. The presence of polymers further increased their adsorption on the soil.
The research was founded by National Science Centre, Poland (2021/41/B/NZ9/03059).
How to cite: Kukowska, S., Grygorczuk-Płaneta, K., and Szewczuk-Karpisz, K.: Changes in soil structure and sorption capacity after mixed treatment with macromolecular compounds and orange peels-derived activated carbons , EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-19332, https://doi.org/10.5194/egusphere-egu26-19332, 2026.
