Lake Tziscao is one of the water bodies belonging to Lagunas de Montebello National Park, located in the south-southeastern part of the state of Chiapas, Mexico. Its importance lies in its great tourist activity due to its size and nearby human settlement, which is why there are numerous anthropogenic factors that promote the transformation of natural areas within it.

In this work, PHREEQC software was used to perform inverse hydrogeochemical modeling, with which the predominant hydrogeochemical processes of the site were identified and estimated using 20 sampling points distributed along Lake Tziscao.

Prior to the execution of the model, a statistical analysis, simplification and graphic representation of samples, as well as a site analysis were carried out, whose comparison results coincide with the presence of calcic-magnesic bicarbonate type waters, suggesting the feasibility of the proposed model.

Modeling results indicate that the main processes present in the water-rock interaction in the area are: hydration of anhydrite and subsequent dissolution-precipitation of gypsum in large proportion, minimal transfer or equilibrium in carbonate minerals and halides such as calcite, dolomite, sylvite and halite, nonetheless, the concentrations of elements such as nitrogen and phosphorus within the water body suggest anthropogenic pollution sources, while the relatively low salinity indicates that the waters are poorly evolved or have been transported to a lesser extent.

How to cite: González Herrera, C. R. and García Villanueva, L. A.: Identification of hydrogeochemical processes through inverse modeling in PHREEQC in Lake Tziscao, belonging to the Montebello lagoon system in Chiapas, Mexico., EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-26, https://doi.org/10.5194/egusphere-egu24-26, 2024.

The abandonment of industrial waste frequently leads to acid drainage affecting groundwater and severely impacting the environment or urban infrastructure. The severe impacts of the acid drainage are related, besides the extremely low pH reached in the affected waters, to the subsequent mobilization and spread of toxic heavy metals such as As, Fe, Cu, Cd, Ni, Pb, and Zn in highly oxidizing environments. The hydrogeology and hydrochemistry of an urban area in Al-Mozara (Zaragoza, Spain), built over an old industrial zone with pyrite roasting waste deposits that experienced acid drainage problems, has been investigated and modelled. Drilling and piezometer construction, and groundwater samples taken during the activities of the SAGE4CAN project, revealed the existence of a perched aquifer within old sulfide mill tailings, where the building basements interrupted the groundwater flow leading to a water stagnation zone that reached extreme acidity values (pH < 2), by drastically increasing the reaction times. A groundwater flow reactive transport model was developed with the software PHAST to reproduce flow and groundwater chemistry, to be used as a predictive tool for guiding and selecting the optimal remediation actions. The model reproduced the measured groundwater chemistry by simulating the kinetically controlled pyrite and portlandite dissolution. Further, the model predicts that an extreme acidity front (pH < 2), coincident with the Fe (III) pyrite oxidation mechanism taking dominance, is propagating by 30 m/year. The incomplete dissolution of residual pyrite (up to 18 % dissolved by the end of the simulations) predicted by the model indicates that the acid drainage in this aquifer is limited by the flow regime rather than by sulfide availability. The construction of additional water collectors between the recharge source and the stagnation zone has been proposed, together with periodical pumping out of acid water from the stagnation zone. The study findings are expected to serve as a useful background for the assessment of acid drainage and remediation techniques in urban areas by numerical modelling, since urbanization of old industrial land is rapidly increasing worldwide. 

How to cite: Jiménez, J., Marazuela, M. Á., Baquedano, C., Martínez-León, J., Sanchez Navarro, J. Á., Cruz-Pérez, N., Santamarta, J. C., and García-Gil, A.: Reactive transport model of an extreme acidic perched aquifer within roasted pyrite waste in a fully urbanized area (Zaragoza, Spain) , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-20228, https://doi.org/10.5194/egusphere-egu24-20228, 2024.

In the past 20 years, the occurrence of tungsten-related health and safety incidents has drawn the close attention of scholars to the toxicity of tungsten and its health and environmental effects. The upper limit of tungsten concentration in water, its mobility and toxicity are all closely related to its speciation. Although polytungstates have been proven to be more toxic and migratory than monomeric tungstates, there is limited information about their abundance in natural environments due to the lack of a reliable analytical approach for determination. In this study, we conducted a simultaneous analysis of monomeric and polymeric tungsten species in natural water using reverse-phase ion pair chromatography coupled with inductively coupled plasma mass spectrometry. Polytungstates and five monotungstates, including tungstate as well as mono, di, tri, and tetrathiotungstate, were chromatographically separated within 35 min of using ethanol (12 - 48% gradient) as the mobile phase. The detection limit of polytungstates was 1.50 µg/L. Although common for the analysis of metals, experimental studies based on electrospray ionization - high resolution mass spectrometry (ESI-HRMS) have indicated that samples containing polytungstates should not be acidified, as it could result in the transformation of monotungstates to artifact polytungstates. Overall, our study offers an effective method for the analysis of various tungsten species, especially polytungstates, at environmentally relevant concentrations.

How to cite: Zhao, Q. and Hu, S.: Reverse phase ion pair chromatography coupled with inductively coupled plasma mass spectrometry as a method for tungsten speciation in natural waters, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-17460, https://doi.org/10.5194/egusphere-egu24-17460, 2024.

Geochemical sampling has limitations due to budget constraints and restricted access to certain areas. This results in some regions being unsampled, making it difficult to generate comprehensive geochemical anomaly maps and distinguish between background values and anomalies. To address this, different interpolation models have been developed, such as inverse distance weighting (IDW) and kriging techniques. However, both IDW and kriging only consider the horizontal distance between samples and ignore elevation changes, which is important in real-world terrains. This effect is most pronounced in mountainous terrains. To address this, we propose a new interpolation technique called Inverse Radius Weighting (IRW). IRW factors in both horizontal distance and elevation changes between sample pairs, resulting in more accurate predictions. Detailed elevation data is available for the entire globe in the form of digital elevation maps from the Shuttle Radar Topography Mission (SRTM) and other sources. In this research, both IDW and IRW models were applied to soil samples in Cyprus. A comparative analysis between IDW and IRW models showed that IRW gives more accurate predictions, especially in terrains with complex morphologies. IRW's ability to account for topographical influences makes it the preferred choice in such scenarios.

How to cite: Sadeghi, B., Morrison, S., Eleish, A., and Klump, J.: Inverse Radius Weighting (IRW) interpolation model: A new interpolation considering morphology, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-1348, https://doi.org/10.5194/egusphere-egu24-1348, 2024.

Provenance studies of flint artefacts provide important means for interpreting raw material procurement strategies, which testify to the level of expertise and environmental knowledge of prehistoric people. Due to its importance, different approaches and methods have been used in order to address this topic, which often makes it difficult to compare different studies. During the recent years we have been exploring the potential of bulk rock composition of flint measured using inductively coupled mass-spectrometry (ICP-MS) for provenance studies. Through the systematic sampling of flint from all across Israel (now archived at the Geological Survey of Israel, as part of the developing national flint collection) and the investigation of a large suite of trace elements, we have been developing a robust approach for determining the provenance of flint. By sampling several specimens from each locality and measuring a large array of elements, we additionally address the variability of compositional data in natural rock sources, and develop a statistical framework for evaluating the uncertainty involved in the provenancing of flint. These developments have been applied in recent case studies in key archaeological sites, and shed new light on the old question of flint provenance in prehistory.

How to cite: Ben Dor, Y., Finkel, M., Sharon, G., Tirosh, O., Bar, O., and Ben-Yosef, E.: Recent advances in flint provenance studies in Israel developed by combining geochemical and statistical perspectives, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-2817, https://doi.org/10.5194/egusphere-egu24-2817, 2024.

The study of ancient aqueducts shows us how past societies used water resources such as rivers, lakes, springs and groundwater. Such resources were tested for their quality, captured, sometimes diverted or abandoned, or supported by a new source. The efficient management of ancient water supply systems was adapted to societal needs, to the chosen environment and to change in climate and population dynamics, similar to factors shaping our modern water management. The in-situ carbonate deposits of ancient water supply systems reflect characteristics of the water resources and aquifers used, and therefore constitute an archive with considerable research potential, particularly for better understanding of ancient water management, palaeo-environment, and water scarcity.

            Ancient aqueducts were long-lived structures, with recorded operation periods of up to 800 years such as the more than 400 km long Valens aqueduct of Constantinople. However, carbonate sequences are often shorter because of cleaning. The Valens aqueduct has a double channel to allow cleaning without interruption of the water supply, and shows only 27 years of carbonate deposits. A carbonate sequence of 250 years is documented for the ancient city of Nemausus, which correlates with the actual documented years of operation. This is because some aqueducts were built wide enough to allow smooth operation without being cleaned of carbonate for most of their length. The aqueduct of Arelate was modified by reallocation of branches and expansion, probably in response to increasing and changing demand of water. In at least 50 years of carbonate stratigraphy, this aqueduct shows periodic variations in the aquifer.

            As the focus of this paper we discuss the Roman aqueduct of Divona, which shows evidence of regular cleaning, repairs, modifications and even timing of maintenance, captured in aqueduct carbonate. The d¹⁸O profile of the carbonate stratigraphy shows a cyclicity that is inferred to reflect annual water temperature variations in the channel. This cyclicity was used to determine the timing of maintenance. The aqueduct operated for centuries but the preserved profile shows 88 years of operation, interrupted by two plaster repair events, representing time breaks in water supply of at least several months. Not less than 14 carbonate removal events were recognized, which took place in fall, spring, or winter but never in summer, with an interval of 1 to 5 years. Carbonate removal from channels was done rapidly, in less than one month, since stable isotope cycles show no indication of a long-term interruption in the water supply. The last maintenance was done only three years before the final abandonment of the water supply, showing that continued operation of the aqueduct was planned but was not fulfilled. This micro-story shows how a historical water management operated and adapted to water scarcity and population growth and decline, similar to modern days. Frequent cleaning of aqueduct carbonate and repairs are examples of what we call today “sustainable” water management.  

Ancient aqueducts carbonates are models to study aspects of past water management and adaptations to crisis, and provide a vision for the future of water availability and climate change.

How to cite: Sürmelihindi, G. and Passchier, C.: Lessons learned from the maintenance of ancient aqueducts through their carbonate archives, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-4708, https://doi.org/10.5194/egusphere-egu24-4708, 2024.

The project focuses on a provenance study carried out on Zeus/Owl bronze coins, coming from the Greek colony of Velia in southern Italy, and dating back to the 3rd century BC. Chemical elemental composition and lead isotope analyses were carried out at the Laboratori Nazionali del Gran Sasso-INFN by using ICP-MS (Inductively Coupled Plasma Mass Spectrometry) and TIMS (Thermal Ionization Mass Spectrometry) techniques. Lead isotope ratios of the coin samples were compared with data from various ore deposits in the main Mediterranean areas documented in existing literature. Additionally, the elemental composition was examined to establish distinctive geological characteristics aiding in identifying the provenance sources of the studied coins. The majority of the coins exhibited an isotope signature of the lead, that makes up the alloy, overlapping with multiple clusters in the Aegean Greece area (Syros, Kea, Antiparos, Serifos and Sifnos) and the Spain South-East area (Cartagena-Mazarron and Almeria). Six coins displayed an uncertain provenance, suggesting the possibility of mixing and/or metal recycling. Notably, one coin demonstrated overlap with both Spain South-East and Tuscany clusters, indicating a shared provenance probability. Regarding the results of the elemental analysis, the main elements that make up the coins alloy are copper, lead and tin. The Pb content ranges considerably from a minimum of 0.5% to a maximum of 24.9%, while the concentration of Cu ranges from a minimum of 73.3% to a maximum of 93.5% and that of Sn ranges between 1.7% and 10.3%. This information contributes to the reconstruction of historical trade routes, enhancing our understanding of the dynamics of metal supply and socio-economic relationships in Velia.

Keywords: Provenance study; Isotopes; Ancient Coins; Ore Deposit; TIMS

How to cite: Ercoles, I., Castorina, F., Nisi, S., Carbone, F., Pardini, G., and Trincherini, P. R.: Provenance Analysis of Zeus/Owl bronze Coins from Velia: A Comprehensive Study using ICP-MS and TIMS Techniques, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-5724, https://doi.org/10.5194/egusphere-egu24-5724, 2024.

Materials research applied to archaeological ceramic artefacts has garnered widespread interest among scientists, architects, engineers, and archaeologists focused on safeguarding architectural heritage. These ancient structures within historic city centers encapsulate the distinctive history and visual essence of each city across different eras. Assessing both old and new materials following damage to these historical edifices becomes crucial for predicting their behaviour during restoration. This endeavour not only aims to analyze and preserve these artifacts but also aims to explore the knowledge and craftsmanship involved in their creation and use. Characterizing building materials primarily targets preservation and restoration goals, encompassing the origins of historical raw materials, understanding archaeological artifact changes, determining original firing methods, and reconstructing manufacturing technologies. Bricks and ceramics, resembling fired artificial rocks, retain geological imprints from their claystone origins, impacted by local geological settings influencing material availability and building techniques. Take, for instance, Ferrara, a Medieval city in Northeast Italy, strategically positioned between the Adriatic Sea and the Po alluvial plain. Its prosperity during the Renaissance under the Estense family was bolstered by extensive modifications to the city, predominantly utilizing locally abundant silico-clastic sediments for construction.

The focus of this research on historical bricks and terracotta decorations from prominent Medieval and Renaissance buildings in Ferrara is to understand the composition of these ancient materials to aid in planning effective restoration treatments, identifying causes of decay, selecting suitable replacement materials, and avoiding incorrect restoration choices. Analyzing the chemical and geological attributes of these materials provides valuable insights into their manufacturing techniques and origins. Moreover, by comparing obtained data with regional sediment records, it has been possible to ascertain the nature and sources of the original raw materials.

How to cite: Marrocchino, E. and Vaccaro, C.: Geochemical characterization of bricks and terracottas used in historical monuments in Ferrara (Italy): Reference to raw materials and production technique, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-19518, https://doi.org/10.5194/egusphere-egu24-19518, 2024.

This research work focuses on reconstructing the anthropogenic fingerprint of the past 150 years through the high-resolution analysis of trace organic compounds preserved in Antarctic ice.

Over the decades, numerous persistent and semi-volatile organic pollutants were largely used in several industrial activities. Some of them proved to be highly toxic, posing a serious threat to human health and natural ecosystems. Consequently, international bans and agreements were established to reduce their industrial production. As a result, restrictions on one compound have led to increased emissions of other chemical substitutes. A rise-and-fall trend in the concentrations between well-established and emerging pollutants is expected in response to international legislative measures. High resistance to biodegradation and semi-volatility promote the long-range atmospheric transport of these molecules, which reach remote areas such as polar regions, where they accumulate as a result of cold condensation processes.

The extraction site GV7 (70°41' S, 158°51' E, 1950 m a.s.l.) is highly significant since it presents a high snow accumulation rate (241 ± 13 mm we yr-1). This feature, rare in recent archives, enables the analysis of trace organic compounds that would otherwise require considerably high amounts of matrix. The ice core (length: 50 m; diameter: 100 mm) is an ideal archive to investigate the “Great Acceleration” since it spans the last 150 years.

The novel analytical method specific for snow and ice applied in this work allows to recognize the evolution of a single compound over time in response to international bans and social changes. The multi-proxy approach adopted allows to identify trends in well-established and new generation organic pollutants as well as personal care products. More specifically, fragrances are compounds of increasing interest since they provide information on use and consumption related to changes in household and social habits.

Solid-phase extraction (SPE) combined with gas chromatography coupled with triple quadrupole mass spectrometry (GC-MS/MS) enable to significantly increase the analytical signal. In addition, samples were entirely processed in a stainless-steel clean room to reduce contamination, achieve low detection limits, and obtain high-resolution data.

Results show a change in the concentration of each compound on a time frame of 150 years. Since this is a pilot study, the processes involved in the transport and deposition of the analytes in deep ice are not yet fully understood and need further investigation. It is necessary to take into consideration possible changes in the use and consumption of organic molecules and potential variations in atmospheric transport.

Previous studies provide data on personal care products on surface snow, which are essential for a broader interpretation of the processes involved.

How to cite: Genuzio, G., Vecchiato, M., Argiriadis, E., Spolaor, A., Frezzotti, M., Barbante, C., and Capodaglio, G.: Trace organic compounds in an Antarctic ice core: a high-resolution analysis to reconstruct the anthropogenic fingerprint, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-15658, https://doi.org/10.5194/egusphere-egu24-15658, 2024.

Our research presents a thorough analysis of climatic and environmental transformations in the Central Dnieper Basin (CDB) during the Middle and Late Pleistocene. It focuses on the study of glacial features left by the Dnieper lobe of the Saalian ice sheet and the co-occurring loess covers, as expressions of Pleistocene climatic fluctuations and landscape changes.
The research includes a detailed analysis of loess distribution, revealing a clear contrast between isolated loess patches in the northern lowlands and a continuous, thick loess cover in the south, especially from the latitude of Kyiv. These covers contain well-developed paleosols, reflecting interglacial changes, which form the basis for deep chronostratigraphic correlations on a regional and supra-regional scale. A key element of the study is resolving unresolved stratigraphic issues of the Pleistocene in Ukraine, with particular emphasis on the chronostratigraphic position of loess and paleosol units in the context of global climatic stages.
The main aim of the research is to identify local environmental influences on recorded Quaternary events following the deglaciation of the Dnieper lobe, to reconstruct the interactions between landscape changes post-glacial retreat and aeolian systems, and to establish a comprehensive and reliable stratigraphy for the Quaternary deposits of the Central Dnieper area. The methodology includes the application of a wide range of multidisciplinary techniques, including detailed grain size distribution and chemical composition analysis, advanced colourimetric measurements, paleomagnetic studies and luminescence dating. The research is based on original and older (palynological) studies on the Pleistocene, highlighting the importance of loess-palaeosol sequences in reconstructing the environmental history of the region.
The CDB, located at the juncture of the Dnieper Upland and Dnieper Lowland, provides unique insights into glacial, fluvial, and loess accumulation. Research includes detailed lithological and pedological sediment characterizations at key geological sites. Results of laboratory analysis clarify transport, deposition, and transformation processes of glacial and aeolian materials, indicating significant loess autochthony. Thermal and precipitation data from pollen analysis of mineral-soil sediments highlight the climatic condition's spatial and temporal variability in the CDB. Biome analysis shows varied landscape mosaics in each cycle, with no total deforestation in climatic pessima or complete afforestation in interglacial optima. These findings offer new insights into the CDB's complex Pleistocene stratigraphy, evidencing the last ice sheet's advance in the Dnieper valley during MIS8, and its link to ana- and kataglacial L3 loess sedimentation phases. They also emphasize the local variability and diversity of soil cover evolution and transformation after the glacial retreat, influenced by the post-glacial topography.
Our research significantly broadens the understanding of environmental changes in the Middle and Late Pleistocene in the CDB, contributing to the development of stratigraphic models and paleoenvironmental reconstructions on both regional and global scales.
Research carried out as part of the grant of National Science Centre, Poland as the project no. 2018/31/B/ST10/01507 entitled “Global, regional and local factors determining the palaeoclimatic and palaeoenvironmental record in the Ukrainian loess-soil sequences along the Dnieper River Valley – from the proximal areas to the distal periglacial zone”.

How to cite: Łanczont, M., Mroczek, P., Komar, M., Nawrocki, J., and Standzikowski, K.: Deciphering Middle-Late Pleistocene environmental changes: a multidisciplinary approach to Middle Dnieper loess-palaeosol sequences, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-8265, https://doi.org/10.5194/egusphere-egu24-8265, 2024.

The Almadén mercury mining district, located in South-central Spain, has been the most important producer of this element worldwide, until the cessation of exploitations in year 2003. The environmental consequence of this activity affects an area of some 250 km², coincident both with a geological structure (the Almadén syncline) and a river basin (the Valdeazogues river and tributaries). The old cinnabar (HgS) mines and mineral showings are scattered in the syncline and in the basin, favouring a wide distribution of the elements in the soils and sediments, as reported by previous publications from this research group and partners.

Crayfish (Procambarus clarkii) is an exotic river crab, with has replaced the autochthonous one  (Austropotamobius pallipes) due to its voracity. It is very common all along the Valdeazogues river and tributaries, and it is captured and consumed by local population in summertime, when it is easily captured in the ‘tablas’, water accumulated in river pods during the cessation of water running due the stational drought. Preliminary data on the Hg contents in this species, obtained in year 2005 reach up to 9,060 ng g^-1 (in muscle) and 26,150 ng g^-1 (in hepatopancreas), according to some previous publications of this research group.

In this communication we present new data on this issue, obtained during the year 2022 along the Valdeazogues river and in some of its tributaries. In this research, 330 crayfish (sizes between 7 and 12 mm) were captured from upstream of the El Entredicho open pit mine to downstream of the confluence with the Guadalmez river (about 36.3 km), as well as the Los Álamos stream, and the Azogado stream, both tributaries of the Valdeazogues. All specimens were analysed by Zeeman effect atomic absorption spectrometry.

The overall results showed maximum values of 3,567 ng g^-1 of total Hg in muscle tissue, with a mean value for the district of 1,617 ± 920 ng g^-1. In hepatopancreas which is an organ of the digestive tract with functions of absorption and storage of nutrients, as well as synthesis of digestive enzymes, the maximum value is very similar: a maximum of 3,590 ng g^-1, while the mean is slightly lower, 1,025 ± 1,028 ng g^-1. For the whole population, the relationship of Hg content in muscle tissue and hepatopancreas with size is not appreciable, probably because they are organisms of fast grown, and there is no general relationship between age and size. On the other hand, there is a relationship between Hg in hepatopancreas and salts contents and total Hg concentration in the nearby sediments.

How to cite: Higueras, P., Barquero, J. I., Bakale, F., Esbrí, J. M., and García Ordiales, E.: Bioaccumulation of mercury in muscle tissue and hepatopancreas in red crayfish (Procambarus clarkii) in a transect of the Valdeazogues river and tributaries, Almadén Hg mining district, south central Spain. , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-9369, https://doi.org/10.5194/egusphere-egu24-9369, 2024.

Local glaciers and ice caps in the Northern Hemisphere and the Greenland Ice Sheet (GrIS) have recently been suggested to be important parts of the Arctic mercury (Hg) budget. Based on ice-core data, the recently estimated total glacial Hg pool is approximately 2,400 tons, approximately 97% of which is in Greenland¹. With Hg concentrations in pre-industrial ice being significantly lower than in ice formed during the 19th and 20th centuries, the dominating source of glacial Hg and input to the Arctic Hg budget is ascribed to long-range transport of anthropogenic Hg emissions².

Alarming concentrations of Hg in meltwater from the western margin of the GrIS were recently reported³. With Hg concentrations reported as being 100 - 1000 times higher than what is known for other freshwater systems of Greenland and a postulated increase in Hg export to downstream environment following climate warming and asserted global importance of Hg fluxes from the GrIS, these extraordinary concentrations and conclusions calls for independent verification.

In our current study⁴, we expand the sampling of subglacial meltwater from 21 representative outlets at GrIS in 2021 and 2022 to get a better scientific basis for conclusions on the magnitude of glacial Hg sources in Greenland. Results from our study consistently show that both total and dissolved Hg concentrations in glacial meltwater over space and time are very low (generally <10 pM) and that an extremely elevated Hg concentration range (up to 4000 pM recently reported³) cannot be reproduced.

In contrast to what was previously reported³, we find that meltwater from below the GrIS is very low in Hg; has minor implications for the global Hg budget and pose only a very limited risk for local communities and the natural environment of Greenland.

References:

• A. Dastoor, et al. (2022), Arctic Mercury Cycling. Nature Reviews Earth & Environment 3, 270–286 (2022). https://doi.org/10.1038/s43017-022-00269-w.
• AMAP. AMAP Assessment 2021: Mercury in the Arctic. Arctic Monitoring and Assessment Programme (AMAP),1- 324.
• J. R. Hawkings et al (2021) Large subglacial source of mercury from the southwestern margin of the Greenland Ice Sheet. Nature Geoscience 14, 496–502 (2021). https://doi.org/10.1038/s41561-021-00753-w.
• Jørgensen et al (2024) Large mercury release from the Greenland Ice Sheet invalidated. Science Advances, in press.

How to cite: Jørgensen, C. J., Søndergaard, J., Larsen, M. M., Kjeldsen, K. K., Rosa, D., Sapper, S. E., Heimbürger-Boavida, L.-E., Kohler, S. G., Wang, F., Gao, Z., Armstrong, D., and Albers, C. N.: No evidence for large mercury release from the Greenland Ice Sheet: recent conclusions on global mercury budget invalidated. , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-4005, https://doi.org/10.5194/egusphere-egu24-4005, 2024.

Mining activities have a severe impact on fluvial systems. The dispersion of huge amounts of heavily polluted wastes contribute to mining-related river pollution due to runoff. Pollutants distribution in fluvial systems is controlled by the interplay between weather conditions (e.g., flooding events), geomorphic processes, and anthropic activities affecting sediments supply, erosion, transport, and (re-) deposition. Mercury (Hg) is listed as a critical contaminant due to its high toxicity, mobility, and persistence in the environment. Its use is progressively banned. As a result, Hg mining is now limited to a few countries. However, legacy mine wastes are still releasing Hg into the environment, particularly to fluvial systems. The Monte Amiata Mining District (MAMD, Southern Tuscany) was the 3rd largest Hg producer worldwide. Four river basins drain the MAMD. Among them, the Paglia River (PR) basin drains the SE sector of the MAMD, covering an area of 1320 km². The widespread Hg pollution and the low resilience to contamination of this river basin was demonstrated in previous studies. Extreme flooding events redistributed huge amounts of polluted sediments across the catchment. The Hg flux discharged by PR to the Tiber River, and ultimately to the Mediterranean Sea, was estimated around 11kg/y. However, this estimate is based on spot samplings. In this study, the relationship between Hg transported by particulate (Hg_p), total suspended solids (TSS) and water turbidity (Tb_w) for PR was investigated to set up a method for the calculation of Hg fluxes from TSS and Tb_w monitoring. Water samples were collected in different hydrological conditions between 2022 and 2023. Samples were taken along the PR, upstream and downstream of the Elvella creek confluence (ECC), a tributary that is not polluted by Hg, to evaluate its effects on the Hg budget. The samples were filtered and the TSS collected on the filters were analyzed for Hg. Part of the samples were analyzed also for Tb_w to investigate the relationship between TSS and Tb_w. TSS ranged between 1.3 and 621.4 mg/L, whereas Hg varied between 0.8 and 321.8 ng/L. Tb_w varied between 12.2 and 358 NTU and a linear relationship was found between TSS and Tb_w. The highest Hg and TSS values were measured during the recession phase of flooding events, whereas the lowest ones were found during low flow conditions. A linear relationship was also found between Hg and TSS. Hg was higher in the upstream samples than in those collected downstream the ECC, confirming that Hg source is the heavily polluted PR basin. The relationship between the two parameters could be applied to the indirect, continuous measurement of Hg fluxes discharged by PR with an automated TSS/Tb_w sensor. Such monitoring would allow assessing the variability of Hg pollution and transport across the PR basin in real time especially in case of flooding, that are expected to become more frequent due to climate change, leading to an increase of Hg delivery to the Mediterranean Sea.

How to cite: Nannoni, A., Annese, V., Fornasaro, S., Morelli, G., Ciani, F., Monnanni, A., Lattanzi, P., Rimondi, V., Costagliola, P., and Fagotti, C.: Particle-bound mercury transport across a mine-polluted fluvial system: towards a simple method to measure Hg flux from the Monte Amiata Mining District (Southern Tuscany, Italy), EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-16063, https://doi.org/10.5194/egusphere-egu24-16063, 2024.

A key aspect for the evaluation of environmental and health risk associated with mercury (Hg) contamination is the assessment of its speciation, which can influence the mobility and bioavailability of this element in the environment. The evaluation of Hg speciation in soils and sediments of contaminated sites is commonly based on selective sequential extraction (SSE) methods, which, however, have certain disadvantages: they do not allow for a specific removal of Hg species, are generally time-consuming and characterised by a low reproducibility. An easy-to-use alternative to SSE may be represented by thermo-desorption (TD) technique, where different Hg species can be identified according to their specific release temperature during a gradual heating. The aim of this study was to evaluate the potential application of TD for the risk assessment associated with Hg occurrence in alluvial soils at some sites in the Friuli-Venezia Giulia Region (NE Italy) affected by past Hg inputs related to mining and, to a lesser extent, industrial activities. At each site, surface and deep soil samples (n≥12) were collected and analysed for total Hg concentration and Hg speciation through TD. Speciation analyses were performed by means of a Hg atomic absorption spectrometer (Lumex RA915M) coupled with a pyrolysis attachment (PYRO-915+). This setup allows for a continuous monitoring of Hg released during the sample heating. Calculations of risk associated to Hg volatilisation, leaching, and ingestion were performed using the relative amount of non-cinnabar (non-α-HgS) compounds determined through TD, considered as potentially mobile. Results were then compared with those obtained through the application of a SSE method commonly used for the assessment of Hg speciation in the investigated area. Almost all samples analysed through TD showed the occurrence of non-mobile red cinnabar (α-HgS), confirming the remarkable legacy of the mining source. Generally, although a slightly higher abundance of potentially mobile Hg forms was obtained through TD than SSE, the calculated risk resulted “acceptable” (hazard index < 1) using data from both techniques. Besides, it must be stressed that calculation performed through TD data are based on a larger number of samples, thus providing a greater representativeness of the mobility of the Hg species and associated risk in the investigated area. Considering also the good reproducibility of data obtained through TD and its celerity and accuracy in Hg species discrimination, the proposed approach could be considered as a valid and relatively low expensive tool for risk assessment at Hg contaminated sites. This is especially true for sites such as former Hg mining areas characterised by the occurrence of α-HgS, easily discriminable through TD.

How to cite: Floreani, F., Pavoni, E., Petranich, E., Antonini, P., Mauri, M., and Covelli, S.: Mercury speciation in soils through thermo-desorption technique as a rapid screening tool for risk assessment procedure at mercury-contaminated sites, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-10434, https://doi.org/10.5194/egusphere-egu24-10434, 2024.

The occurrence of gaseous mercury pollution has to be identified and monitored through innovative methods and techniques, which would serve as a step toward strengthening the knowledge of the mechanisms of mercury dispersion in the atmosphere, in accordance with the provisions of the Minamata Convention on Mercury. Consequently, the aim of this work is to present the very first data obtained by directly and continuously measuring GEM (Mercury Elemental Gas) in the lower atmosphere through an original assembly of a UAV (Unmanned Aerial Vehicle, a heavy-lift octocopter) and a Lumex^® RA-915M (a portable spectrometer for gaseous mercury). A few sites pertaining to both the mining facilities of the former Hg-mining area of Abbadia San Salvatore (Mt. Amiata, Italy) and the surrounding urban zones were selected to test the performance and effectiveness of the UAV-Lumex^® combination at different heights. The octocopter agility and directional versatility, able to stop at selected altitudes, and the Lumex^® great sensitivity made it possible to shed light on the variability of GEM concentrations and to represent its distribution via dot-map graphical visualization, providing a tridimensional picture of GEM profiling during the flights. This approach allows checking in near real-time whether the guideline concentrations are eventually exceeded. More specifically, the acquisition system was optimized through: i) the use of a stand-alone GPS as a synchronization tool for Lumex^® and UAV GPS data; ii) the connection of a vertical sampling tube to the Lumex^® inlet to overcome the strong airflows of the UAV rotors; iii) the use of batteries for power supply to avoid the release of exhaust gases. Moreover, all flights were standardized based on previously acquired data thanks to the method accuracy and the UAV pilot experience, allowing reprogramming and repeating the routes in different times. The results showed significant concentration variations between the urban and the most contaminated mining area, and highlighted the differences when the flight was repeated at a later date.

How to cite: Cabassi, J., Lazzaroni, M., Giannini, L., Mariottini, D., Nisi, B., Meloni, F., Rappuoli, D., and Vaselli, O.: Investigating the 3D distribution of GEM (Gaseous Elemental Mercury) in the lower atmosphere via a UAV (Unmanned Aerial Vehicle) - Lumex® assemblage, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-10879, https://doi.org/10.5194/egusphere-egu24-10879, 2024.

Four jellyfish species, ctenophoran Mnemiopsis leidyi and scyphozoan Cotylorhiza tuberculata, Chrysoara hysoscella and Rhizostoma pulmo were collected in summer of 2017 in the Gulf of Trieste (northern Adriatic Sea) and analysed for Hg and other metal(loid)s to assess their bioaccumulation and biomonitoring potential. No significant differences in Hg levels (0.06-0.22 µg/g dry mass) were observed between the studied species but all significantly concentrated Hg well above the dissolved Hg seawater levels (5 ng/L) of the gulf. The studied species have diverse diets consisting primarily of various plankton groups. C. hysoscella feeds mainly on mesozooplankton (>200 µm) R. pulmo and C. tuberculata mostly consume microzooplankton (50-200 µm) while M. leidyi preys on various organism (and particles) in the water column. In addition, C. tuberculata harbours autotrophic endosymbionts (microalgae). Considering their feeding behaviour, it appears that studied jellyfish species do not bioaccumulate Hg, nor other metal(loid)s, along the pelagic food web. Hence, the Hg levels in jellyfish are probably the consequence of the dissolved metal (passive and active) uptake. Moreover, the methodological approach analysing the jellyfish freeze-dried samples containing salt can distort the real picture and the Hg/C_org. ratio could better describe the metal level in the gelatinous organism. However, considering the high Hg bioconcentration factor (log BCF >5), jellyfish can be used aa a useful bioindicator for Hg, and other metal(loid)s, dissolved in seawater.     

Keywords: Jellyfish, coastal waters, mercury, bioconcentration, contamination, bioindicator

How to cite: Faganeli, J., Tjasa, K., Darja, M., Alenka, M., and Ingrid, F.: Mercury in the coastal pelagic food web: phytoplankton, zooplankton and jellyfish, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-22463, https://doi.org/10.5194/egusphere-egu24-22463, 2024.

Geochemical prospecting is a valuable tool for investigating the influence of the geological context on the composition of stream sediment and determining the existence of any natural or anthropogenic geochemical anomaly within a river catchment basin. Several indices have been proposed in scientific literature to assess sediment's environmental quality and the ecological condition of catchment basins. In environmental studies, these indices are usually based on applying ratios among the raw geochemical composition of the sediment at the sampling location and a value assumed as a reference for the undisturbed conditions (Background/baseline). However, the reference values are often determined while overlooking the potential influence of river dynamics on the variability of sediment composition, and this can compromise the robustness of the contamination assessment.

As a matter of fact, the chemical composition of a stream sediment sample is representative of the relative upstream catchment basin. The Sample Catchment Basin (SCB) method, which accounts for the dynamic nature of rivers, has been largely used in literature to correct the dilution effect impacting the composition of stream sediment, aiming at determining reliable geochemical background values to be used for mineral prospecting.

The main purpose of the study was to check if the use of the correction of the dilution effect to determine background values could also improve the performance of some contamination indices, favouring a more effective and accurate assessment of the environmental degradation affecting a river basin.

The Sarno River, known for its susceptibility to contamination from urban and industrial sources, served as a pertinent case study. A total of 96 samples were used to define the zone of influence of each sample through the elaboration of geomorphological and hydrological features; then, the background concentrations of each element were estimated by calculating the weighted average element content based on the areal proportions of lithologic units in each sample catchment basin. The values deriving from this step were then used as a reference to calculate the degree of contamination for each SCB.

The contamination indices were calculated and mapped by using both non-diluted and dilution-corrected background data.

A comparative analysis was performed among the results obtained to assess if sensitive changes occurred to the spatial and statistical distribution of used indices and to determine if an improvement in performance could be obtained.

 This study represents a methodological benchmark for future research focusing on environmental risk assessment of stream sediment.

How to cite: Iannone, A., Guarino, A., Pacifico, L. R., and Albanese, S.: Can contamination indices performance be improved by accounting for the dilution effect when dealing with stream sediments? A case study from southern Italy., EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-16836, https://doi.org/10.5194/egusphere-egu24-16836, 2024.

In regional or local scale geochemical mapping, the choice of sampling media and analytical methods will be influenced by the source, form, mobility and spatial distribution of elements being mapped. For environmental monitoring and mineral exploration there are potential advantages in using plant organs rather than regolith materials as the sampling media, including the capacity of plants to sample large volumes of underlying regolith and the averaging of their biogeochemical composition over timeframes extending from months to years. The limited use of plant organs in geochemical mapping relates partly to perceived complicating factors such as variability between plant species, seasonal variability in some plant organs and analytical costs.

Needle samples from over 4,000 cypress pines (C. glaucophylla) in the highly mineralised Cobar Basin in central New South Wales have been analysed by both ICPMS and pXRF. The study spanned regional mapping using samples collected adjacent to roads and tracks, and detailed grids and traverses across 36 mineral prospects and deposits. For various major and trace elements, there is strong correlation between results obtained by total digestion ICPMS and by portable XRF, including direct pXRF analysis of unprocessed samples in the field.

There are distinct lithological influences on variation in the background values for various elements, including Au and Pb, noting that the majority of mineral deposits are structurally hosted within the Devonian sandstone and siltstones regionally intruded by felsic intrusives. There is an extensive zone of elevated base and precious metal values in the needles between the Peak Au mine site and the city of Cobar which was the focus of mineral processing for many decades. Highly elevated values for Ag, Au, Pb, Zn, Ni, Co, W and/or REE occur above known mineral deposits, depending on deposit style, and commonly display more consistent geochemical spatial patterns than in regolith samples. Pines in general typically restrict uptake of Cu in the needles to within the range of 3–12 ppm due to its function as an important trace nutrient.

How to cite: Schifano, J., Cohen, D., and Rutherford, N.: Pining for an Anomaly: Exploration and environmental assessments using regional and local scale biogeochemical patterns in the Cobar Region, Australia., EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-1404, https://doi.org/10.5194/egusphere-egu24-1404, 2024.

Understanding the transfer of contaminants from soil to plants, especially agricultural products, is essential in environmental science, particularly in the context of risk assessment and the development of sustainable agricultural practices. The estimation of transfer factors (TFs) (Singh et al., 2011), which quantify the uptake of elements or pollutants by plants from the surrounding soil, serves as a crucial parameter in evaluating potential ecological and human health risks, as these elements could enter the food chain (Ozhovan and Kremenetskiy, 2018).

For this study, the Transfer Factors soil-to-plant were estimated using the bioavailable concentrations (Guarino et al., 2022) of Potentially Toxic Elements (PTEs) identified by Italian law (D.lgs. 152/2006) in the agricultural soils and the elemental concentration in the primary agricultural products (PAP). These latter are freshly harvested fruits and vegetables, which retain their integrity and freshness as they have not undergone significant processing, collected across the entire region through the Campania Trasparente project (www.campaniatrasparente.it).

The aim of this study was to compare various Transfer Factors (TFs) among the most numerous vegetal species and potentially highlight different behaviours. A robust multivariate statistical approach, such as Robust Principal Component Analysis (RPCA) was applied to the TFs, and a multiple regression, using the stepwise method, was performed, with Principal Components as dependent variables and soil physical parameters (grain size, organic matter, pH, cation exchange capacity, salinity, electrical conductivity) as independent variables.

Our findings reveal distinct patterns in the soil-to-plant transfer factors for various elements, emphasizing the role of soil properties, plant species, and environmental conditions. Results reveal that, within the Campania region, the highest TFs for the most vegetal species are associated with Zn and Cu. Specifically, RPCA indicates a positive correlation between Zn and Co TFs. In the end, the multiple regression analysis highlights that clay presence and cation exchange capacity are the primary soil physical factors influencing TFs across different plant species.

This integrated approach could provide a comprehensive understanding of soil-plant transfer processes and the impact of soil physical parameters on TFs in regional cultivations. The study helps better understand the impact of soil physical parameters, such as cation exchange capacity (CEC), grain size, organic matter, etc., on vegetal species growth. It can lead to well-informed decisions regarding crop selection, fertilizer application, irrigation, and other factors.

References:

Guarino, A., Albanese, S., Cicchella, D., Ebrahimi, P., Dominech, S., Pacifico, L.R., Rofrano, G., Nicodemo, F., Pizzolante, A., Allocca, C., Romano, N., De Vivo, B., Lima, A., (2022). Factors influencing the bioavailability of some selected elements in the agricultural soil of a geologically varied territory: the Campania region (Italy) case study. Geoderma 428, 116207.

Jaswant Singh, Suraj K. Upadhyay, Rajaneesh K. Pathak & Vidhu Gupta (2011). Accumulation of heavy metals in soil and paddy crop (Oryza sativa), irrigated with water of Ramgarh Lake, Gorakhpur, UP, India, Toxicological & Environmental Chemistry, 93:3, 462-473.

Ozhovan M, Kremenetskiy A. (2018). Transfer Factors: Concepts and Applications in Soil-Plant Systems. Boca Raton, FL: CRC Press.

How to cite: Pacifico, L. R., Guarino, A., Iannone, A., Pizzolante, A., Esposito, M., Brambilla, G., and Albanese, S.: Comprehensive analysis and multivariate statistical approach of Transfer Factors soil-to-plant estimated from bioavailable concentrations in agricultural products: the case study of the Campania region (Southern Italy), EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-17147, https://doi.org/10.5194/egusphere-egu24-17147, 2024.

The EU-funded CRM-geothermal project aims to integrate the extraction of critical raw materials and geothermal heat from deep geothermal reservoirs. Within the project, extraction technologies and their economic and environmental feasibility are tested and evaluated across several geological regions in Europe and East Africa.

  The focus of this study is the North German Basin, a typical sedimentary basin that initiated rifting in the late Carboniferous period, accumulating various sediments to a thickness of up to 10–12 km. Located in central Europe it stretches over an area from Poland to the Netherlands, traversing across North Germany.

The succession is beginning with Permian volcanic rocks at the base, and overlain by alternating layers of mud-, silt- sandstones and evaporates; some of which have already been identified for geothermal energy extraction (e.g. Neustadt-Glewe, Schwerin, and Potsdam). Up to now, the extraction of lithium (Li) has not been explored, despite the existence of elevated Li concentrations occurring in formation fluids of the Rotliegend and Bunter sandstone.

In this study the potential content of selected critical and valuable elements (Li, Sr, Cu) and their availability in various formations of the North German Basin was assessed. For this purpose, cuttings from different formation rocks from one deep well (GrSk04/05; 4000 m depth) were first analyzed for bulk concentrations of these elements. Most promising samples (with Li up to 74 ppm, Cu up to 214 ppm, and Sr with up to 2334 ppm) were selected from Muschelkalk, Bunter sandstone (Dethfurt), Zechstein (Ohre), Permian Rotliegend sandstone (Hannover), and volcanic rocks)  for a sequential extraction. This method provides indication on the type of elemental bonding within minerals, allowing to estimate the availability and sustainability of the CRM in the respective formation fluids.

How to cite: Regenspurg, S., Thomas, A., Stammeier, J. A., Schiepersky, F., Scheck-Wenderoth, M., and Kieling, K.: Critical raw materials from geothermal fluids: Potential in the North German Basin, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-19791, https://doi.org/10.5194/egusphere-egu24-19791, 2024.