BG1.13 | Environmental Changes and Pollution Dynamics, Methods and Monitoring under past and future Global Change Scenarios
Environmental Changes and Pollution Dynamics, Methods and Monitoring under past and future Global Change Scenarios
Co-sponsored by JpGU
Convener: Maria Dolores Basallote | Co-conveners: Petra Heinz, Hiroshi Kitazato, Takashi Toyofuku, Carlos Ruiz Cánovas, Ana Romero-Freire, Araceli Rodríguez-Romero
Orals
| Tue, 16 Apr, 14:00–15:45 (CEST), 16:15–18:00 (CEST)
 
Room 2.17
Posters on site
| Attendance Mon, 15 Apr, 10:45–12:30 (CEST) | Display Mon, 15 Apr, 08:30–12:30
 
Hall X1
Orals |
Tue, 14:00
Mon, 10:45
Marine, freshwater and soil systems are interconnected components in the environment, that play crucial roles in the overall functioning of the planet's ecosystems and regulating the global climate. In the face of rapidly changing environmental conditions, understanding the response of organisms to changing parameters, including the fate, transport, and impacts of contaminants, is of paramount importance for understanding ecosystem evolution and safeguarding terrestrial and aquatic ecosystems. Today, special attention must be focused on emergent contaminants, including pharmaceuticals, microplastics, and other anthropogenic compounds, which pose novel challenges in the field of environmental sciences.
The session will explore intricate biogeochemical interactions within aquatic and soil environments, elucidating the influence of microbial communities, nutrient cycles, and physical factors on faunal and ecosystem functional responses and contaminant behaviour. The session is multidisciplinary and is open to observational, experimental, and modelling studies in order to promote the dialogue. The session will comprise subsections on 1) biological and ecological experimental biogeosciences and 2) on pollution dynamics.

The session is co-sponsored by JpGU.

Orals: Tue, 16 Apr | Room 2.17

Chairpersons: Petra Heinz, Takashi Toyofuku
14:00–14:05
14:05–14:15
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EGU24-14425
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Highlight
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Virtual presentation
Hiroshi Kitazato

Hadal trench shows integration of landscapes of plate tectonics, geological evolutions of trenches, surface and deep-water circulations, biogeochemical cycles and others.  On these environmental components, we can understand historical backgrounds of benthic organisms. I have long been worked on the deep sea benthic foraminiferal communities at the Western Pacific.  We analyzed localities of the western Pacific deep-sea, from bathyal to abyssal depths, in particular to hadal depths. Hadal foraminiferal community consists of monothalamous soft-shelled forms, agglutinated forms, porcelaneous forms, hyaline forms and large xenophyophores.  In contrast to the bathyal to abyssal depths, the hadal depths are much challenging.   Because, a lot of accidental events take place naturally, such as collisions, subductions, separations or fusion of trenches.  Trenches are fascinating natural laboratories for thinking about evolution of benthic organisms in connection to trenches.

Here, I try to discuss what kind of changes should take place when trench fuse respectively.  Case studies will be given from the late Cenozoic marine strata of the Central Kwanto regions at the central Japan (Kitazato, 1997).

How to cite: Kitazato, H.: Hadal trenches are experimental fields for geological and biological systems, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-14425, https://doi.org/10.5194/egusphere-egu24-14425, 2024.

14:15–14:25
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EGU24-8522
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Highlight
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Virtual presentation
Biomineralization of CaCO3 in the oceans: Seawater is the calcifying fluid
(withdrawn)
Jonathan Erez, Sharon Ram, Hagar Hauzer, Adam Levi, Matan Yona, Yael Levenson, and David Evans
14:25–14:35
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EGU24-18922
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Virtual presentation
Dirk Koopmans, Allison Schaap, Volker Meyer, Paul Färber, Lauren Queiss, Luis M. Montilla, Socratis Loucaides, Soeren Ahmerkamp, and Ulisse Cardini

Calcifying organisms, including scleractinian corals and coralline algae, play a pivotal role in supporting benthic habitats and their associated ecosystem functions. However, many of them are threatened by ocean warming and acidification caused by anthropogenic CO2 emissions. Our understanding of their capacity to adapt to changes in their natural environment remains limited. To address this knowledge gap, we introduce a non-invasive method to quantify calcification from the simultaneous measurement of H+ ion and O2 fluxes utilizing the aquatic eddy covariance technique. Because calcification is a net source of H+ ions, it can be quantified as a source of H+ ions in excess of those generated by organic carbon metabolism. To examine the effect of ocean acidification on calcification by coralline algae epiphytes, we measured H+ and O2 fluxes at a seagrass meadow at a CO2 vent and at a control meadow, 670 m away. At both meadows we found that opposing flows were enriched in vent CO2. Additionally, vent CO2 diffused upwards through sediments at both sites. Because of this, we were unable to completely separate the calcification signal (non-metabolic H+ ion production) from the persistent background signal of vent CO2. However, we use these data as a demonstration of how H+ and O2 eddy covariance can reveal a subtle time-varying signal consistent with calcification in a benthic ecosystem. Based on the results of this study, H+ and O2 eddy covariance can quantify changes in benthic calcification over time, and therefore it can support better-informed management of scleratinian corals, coralline algae, and other benthic calcifiers. 

How to cite: Koopmans, D., Schaap, A., Meyer, V., Färber, P., Queiss, L., Montilla, L. M., Loucaides, S., Ahmerkamp, S., and Cardini, U.: Aquatic eddy covariance pH and O2 fluxes, a technique for observing calcification in benthic ecosystems, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-18922, https://doi.org/10.5194/egusphere-egu24-18922, 2024.

14:35–14:45
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EGU24-16323
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On-site presentation
Daniel Francois Do Nascimento Silva, Lennart de Nooijer, and Gert-Jan Reichart

The Mg/Ca ratio in foraminiferal shells is commonly used as a proxy for reconstructing sea surface and bottom water temperatures. However, its incorporation results from complex interactions between seawater conditions and biologically regulated factors. While the former effects are well-constrained, poorly understood biological factors contribute to interspecies variations in Mg/Ca-temperature calibrations and a notable difference in Mg sensitivity compared to inorganically precipitated calcium carbonates. Here we show that temperature significantly influences cellular ion modulation in low-Mg species, leading to elevated enzymatic reaction rates that enhance H+ removal (J = 0.67 to 5.00 nmol-s) during calcification, and boost the precipitation rate. On high-Mg species, on the other hand, a similar fivefold increase in H+ local flux was observed (J = 0.08 to 0.40 nmol-s), but its impact on the calcification rate was mild. In both cases, H+ pumping rates align with Mg uptake, indicating a potential (indirect) link between temperature-sensitive behavior of transporters and Mg partitioning.

How to cite: Do Nascimento Silva, D. F., de Nooijer, L., and Reichart, G.-J.: Temperature Influence on Proton Pumping and Mg-Incorporation in Foraminifera, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-16323, https://doi.org/10.5194/egusphere-egu24-16323, 2024.

14:45–14:55
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EGU24-18686
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ECS
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On-site presentation
Laura Pacho, Lennart de Nooijer, and Gert-Jan Reichart

Climate reconstructions are important for validating climate models and hence constrain climate change predictions. Such reconstructions are based on indirect tools (proxies) in which a fossil or chemical remnant corresponds to an environmental parameter. When employing foraminifera as proxies, elemental concentrations in their shells have been shown to correlate with environmental parameters including temperature (that determines the calcite’s Mg/Ca), seawater [HCO3-] (Sr/Ca and B/Ca) and [CO32-] (S/Ca). When reconstructing theses parameters on longer geological timescales (i.e. millions of years), the seawater’s major ion concentrations may affect these proxy relationships. Especially the concentration of calcium will affect all of these calcitic elemental ratios and therefore, we varied [Ca2+] in controlled growth experiments to test its effect on incorporation of Mg, Sr, B and S in the benthic foraminifer Amphistegina lessonii. For the divalent cations we find a decrease in the partition coefficient (D) for Mg (DMg) with a changing [Ca2+] (and hence seawater Mg/Ca) while DSr does not vary significantly with [Ca2+]. For SO42- and B(OH)4- against S/Casw and B/Casw respectively, we observe a significant decrease in the partition coefficients with decreasing [Ca2+]. These results gives new information for SO42- and B(OH)4- incorporation and represents a step forward towards comprehending the impact of [Ca2+]sw alterations on foraminiferal calcite chemistry and hence their application as paleoproxies in deep time. 

How to cite: Pacho, L., de Nooijer, L., and Reichart, G.-J.: Partitioning of multiple elements as a function of seawater [Ca2+]: results from foraminiferal culture experiments. , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-18686, https://doi.org/10.5194/egusphere-egu24-18686, 2024.

14:55–15:05
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EGU24-15333
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Virtual presentation
Erik Wolfgring, Giulia Amaglio, and Maria Rose Petrizzo

We investigated the δ11Bisotope profiles in Cretaceous benthic foraminifera, focusing on the epibenthic species Notoplanulina rakauroana and Nuttallinella coronula. This study aims at understanding the implications of changes in δ11B isotope signatures for pH, associated with paleoenvironmental factors during the beginning of the Late Cretaceous cooling in the Santonian in the southern high latitudes.

We examine 10 levels through the Santonian of International Ocean Discovery Program (IODP) Site U1513 in the Mentelle Basin, some kilometres offshore Western Australia. Following a biostratigraphic framework relying on planktonic foraminifera and calcareous nannofossils, foraminiferal samples of Notoplanulina and Nuttallinella, representing significant elements of bottom water fauna through this period of significant cooling in surface and bottom waters, have been processed.

The geochemical signals preserved in the tests of epibenthic foraminiferal species are supposedly less prone to representing vital effects as some stability in the paleohabitat in bottom waters is implicit (see Rae et al. 2011). The analysis of well-preserved foraminiferal tests by Inductively Coupled Plasma Mass Spectrometry (ICPMS) is imperative of a cleaning protocol that involves several steps of ultrasonic baths in clear water and alcohol (see Henehan et al. 2019).

The results of benthic foraminiferal δ11B add information to our understanding of the relationbetween climate shifts and changes in the geochemical composition visible in foraminiferal tests. Results help to reconstruct prevailing pH of bottom waters during the documented reorganization of oceanic pathways in the southern high latitudes and offer a further perspective on the extent of paleoenvironmental change in the bottom waters.

References:
Rae, JWB, Foster, GL, Schmidt, DN, Elliott, T, 2011. Boron isotopes and B/Ca in benthic foraminifera: Proxies for the deep ocean carbonate system, Earth and Planetary Science Letters, 302, 3–4.
Henehan, MJ, Ridgwell, A, Thomas, E, et al., 2019. Rapid ocean acidification and protracted Earth system recovery followed the end-Cretaceous Chicxulub impact. PNAS, 116, 45, 22500-22504.



How to cite: Wolfgring, E., Amaglio, G., and Petrizzo, M. R.: Boron isotope signals of benthic foraminifera during the Santonian, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-15333, https://doi.org/10.5194/egusphere-egu24-15333, 2024.

15:05–15:15
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EGU24-19630
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ECS
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On-site presentation
Adele Westgård, Julie Meilland, Freya E. Sykes, Thomas B. Chalk, Gavin L. Foster, Melissa Chierici, and Mohamed M. Ezat

Proxy based records of past changes in the polar surface ocean-cryosphere-climate interactions can provide invaluable constraints on ongoing and future climate change. However, studying polar ocean palaeoceanography remains challenging largely due to a lack of robust proxy calibrations. For example, the commonly used foraminiferal Mg/Ca paleothermometer does not have a reliable calibration at polar conditions and there are currently limited trace element proxies for other environmental variables such as salinity or carbonate chemistry. In addition, Neogloboquadrina pachyderma, the dominant foraminifera species in polar regions, sometimes grows a thick calcite crust outside its main growth phase calcite with different geochemical composition. This poses a challenge to the Mg/Ca paleothermometer as the crusts have lower Mg/Ca than the ontogenetic calcite.

To address this, we cultivated >1500 individual specimens of N. pachyderma over a wide range of temperatures (2 to 9°C), salinities (~30 to 36.5), pHs (~7.7 to 8.4 total scale), carbonate ion concentrations (~100-250 µmol/mol at stable and variable pH), and Ba concentrations (2-4 times natural). The experimental water was spiked with 135Ba to label laboratory-grown calcite. Elemental ratios in the specimens have been analysed using laser ablation mass spectrometry (LA-ICP-MS), providing high resolution elemental profiles of intra-shell variability.

Our microscopic observations and element ratios results suggest the growth and addition of crust in all treatments, allowing, for the first time, laboratory-based proxy calibrations for N. pachyderma’s crust. A preliminary data analysis show variability in trace element ratios in relation to variable temperature, salinity, barium concentration and carbonate chemistry. Our results also indicate significant distinction in trace element ratios between crust and ontogenetic calcite components of the N. pachyderma tests when both are grown in culture. We are in the process of developing separate laboratory-based proxy calibrations for the crust and ontogenetic calcite which will significantly improve the applicability of the proxy calibrations as well as our understanding of crust formation in this species. We aim to present Mg/Ca-temperature calibrations for the crust and ontogenetic parts separately as well as detailing the respective effects of salinity and carbonate chemistry on Mg/Ca ratios.  

How to cite: Westgård, A., Meilland, J., Sykes, F. E., Chalk, T. B., Foster, G. L., Chierici, M., and Ezat, M. M.: Developing trace element proxy calibrations for reconstructing polar surface ocean hydrography based on laboratory-grown planktonic foraminifera Neogloboquadrina pachyderma, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-19630, https://doi.org/10.5194/egusphere-egu24-19630, 2024.

15:15–15:25
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EGU24-1819
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ECS
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On-site presentation
Haotian Yang, Hong Yan, and Chengcheng Liu

Biogeochemical archive such as tree rings, corals, and stalagmites have proven effective in reconstructing past paleoclimate patterns at year-month resolutions. However, they are not suitable for investigating weather changes on a day-hour scale. Tridacna, the largest bivalve in the world, which inhabits the Tropical-subtropical Pacific-Indian Ocean area, exhibits unique daily growth bands ranging from 5 to 60μm. This characteristic grants Tridacna the potential to reconstruct extreme weather events in the past, thus paving the way for paleoweather studies. Tridacna engages in symbiosis with zooxanthellae and relies on photosynthesis for energy. The growth rate and pattern of its daily growth bands correlate with diurnal alternations. Currently, the utilization of Tridacna daily growth bands and high-resolution geochemical element ratios holds potential for establishing a daily resolution biogeochemical proxy. However, the precise mechanism of the circadian rhythm during Tridacna's growth period in natural conditions remains unclear. Consequently, our comprehension of the pattern exhibited by Tridacna's daily growth bands is limited, impeding progress in the development of hourly scale paleo-weather analysis. In this study, a 30-day artificial experiment was conducted on Tridacna derasa to investigate the significance of shell daily growth bands and hourly element ratios in reflecting environmental conditions. The results of calcein labeling revealed that the wide dim areas in the daily growth bands corresponded to daytime and exhibited valley values in Sr/Ca ratio, while the narrow bright areas corresponded to nighttime and showed peak values in Sr/Ca ratio. At the daily-hourly scale, when the water temperature remained constant, the Sr/Ca daily variation showed potential for recording the light daily cycle. However, it is important to note that the influence of the light daily cycle on the Sr/Ca variation may be indirect. As a result, a hypothesis was proposed: the Sr/Ca variation is directly controlled by the internal regulation of Tridacna. During the daytime, the Sr/Ca ratio was primarily regulated by physiological activities. Due to light stimulation, the activity of certain enzymes in the inner mantle was enhanced, leading to an increase in Ca2+ concentration and a decrease in Sr/Ca ratio. During the nighttime, the Sr/Ca ratio was mainly regulated by organic matrices. In the extrapallial fluid (EPF), the presence of high Sr2+-selective organic matrices promoted the incorporation of Sr2+ into the shell, resulting in a higher Sr/Ca ratio.

How to cite: Yang, H., Yan, H., and Liu, C.: The daily growth bands pattern of Tridacna - evidence from culture experiments., EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-1819, https://doi.org/10.5194/egusphere-egu24-1819, 2024.

15:25–15:35
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EGU24-46
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ECS
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On-site presentation
Sinatrya Diko Prayudi, Asmaa Korin, and Michael Kaminski

Frequent occurrences of high-temperature records have become commonplace during the summer seasons in regions adjacent to the western Arabian Gulf, such as Bahrain, Saudi Arabia, and Qatar. On a daily basis, the fluctuation in daytime and nighttime temperatures, along with varying afternoon temperatures, poses a potential threat to organisms inhabiting intertidal and shallow water environments, whether residing above the substrate or submerged beneath. Surprisingly, there has been no prior scientific investigation into the resilience of these coastal communities, especially from a non-anthropocentric perspective, focusing on the marine calcifying organism that inhabits one of the world's most extreme marine environments. To address this gap, we aimed to determine the upper thermal limits of intertidal calcifying benthic organisms in the western Arabian Gulf region. For this purpose, we selected three representative species among the diverse inhabitants, comprising two gastropod species and one ostracod species. These specimens were subjected to controlled environmental conditions inside a thermal incubator over a short-term period (three hours), with temperature exposures ranging from 40°C to 60°C. We considered different scenarios that replicated their natural ecological conditions: full exposure, partial exposure, and full coverage/submerged underwater. Our comprehensive results revealed that different gastropod species exhibited varying levels of resilience to higher thermal exposure, depending on the scenario (heat comma temperature/HCT ranged between 39°C-48.5°C versus 42.1°C-44.1°C). In contrast, the ostracod displayed remarkable tolerance to higher temperatures than the gastropod specimens before succumbing to complete mortality or entering a comatose state (temperature range of 39.1°C-53.5°C). Furthermore, post-exposure recovery demonstrated that higher heat exposure substantially prolonged the recovery time. In the case of the gastropod specimens subjected to the highest thermal exposure, no successful recovery was observed. Our findings underscore the importance of conducting ecological experiments that involve prolonged exposure to high temperatures. However, it is imperative to recognize that even short-term periods of elevated temperatures can have fatal implications for the target organisms. This is particularly relevant in light of the ongoing warming trend and the recording of extreme temperatures in our regional area in the western Arabian Gulf, which may eventually be deemed a potential "kill zone" during the peak of summer seasons within a short timeframe.

How to cite: Prayudi, S. D., Korin, A., and Kaminski, M.: An Ecological Perspective on Short-Term Heat Exposure Experiments with Marine Calcifying Organisms from the Western Arabian Gulf Region: Insights into a Summer Heatwave Scenario, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-46, https://doi.org/10.5194/egusphere-egu24-46, 2024.

15:35–15:45
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EGU24-5631
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ECS
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On-site presentation
Frederik Gäng, Lena Göller, Volker Brüchert, Niko Lahajnar, Katharina Pahnke, and Philipp Böning

Enrichment patterns of redox- and biosensitive trace elements (TEs) are powerful tools to reconstruct depositional conditions during sedimentation in continental marine sediments. For several TEs (e.g., U, Cr, As and V), the mechanisms that lead to their accumulation in the sediment are not fully understood yet. To complement the discussion, we analyzed several major elements and TEs (P, Ca, Sr, U, V, As and Cr) in fish scales from two short cores (30 cm sediment depth) from the central and southern shelf of the Namibian anoxic-euxinic continental margin (from 67 and 100 m water depth). We found both fresh, young scales in the upper sediments and clearly altered scales, in deeper sections of the cores. The P, Ca and Sr values appear to be good indicators of the changing condition of the respective fish scales, as Ca, Sr and P decrease with the sediment depth from which the fish scales were taken. The lower the Ca, Sr and P values, the more altered the fish scales and the higher the TE enrichment. These more altered fish scales have high values of U (up to 88 ppm), Cr (up to 97 ppm) and V (up to 130 ppm), raising the importance of fish scales as a sink for these elements in shelf sediments, leading to extreme enrichments that are not primarily related to redox conditions. In contrast to the high TE values in altered scales, high values of As (up to 140 ppm) were found in fresh fish scales in core top sections and a decrease with sediment depth. Previous studies showed that high bulk U content in central Namibian shelf sediments is due to high anthropogenic U input by mining activities (in addition to U enrichment during authigenic apatite formation in the sediments). This U-mining activity in the central Namibian hinterland is further reflected in higher U values in the core from the central shelf compared to the core from the southern shelf. The increase of all TEs in scales with increasing sediment depth indicates authigenic enrichment over time within the sediment. Therefore, we suggest that fish scales are an important authigenic sink of several TEs which may be substantial for the element budget calculations in continental margins.

How to cite: Gäng, F., Göller, L., Brüchert, V., Lahajnar, N., Pahnke, K., and Böning, P.: High enrichment of U, Cr, As and V in fish scales from the Namibian shelf of the Benguela Upwelling System., EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-5631, https://doi.org/10.5194/egusphere-egu24-5631, 2024.

Coffee break
Chairpersons: Maria Dolores Basallote, Carlos Ruiz Cánovas
16:15–16:20
16:20–16:30
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EGU24-2520
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On-site presentation
Qingling Zhang, Shan Zhang, Wuzhou Dong, Zhipan Wang, and Zewen Mo

Microplastics, ubiquitous environmental pollutants, pose a significant threat to agricultural ecosystems and food safety. Xinjiang, a critical dryland agricultural region in China, faces a pressing issue with microplastic accumulation due to extensive use of mulching film. This study addresses this challenge by combining feild investigation, lab analysis, and remote sensing observations:

  • Developing an improved, batch-processed soil microplastics extraction method, optimizing cost and time.
  • Extracting and analyzing microplastics from typical Xinjiang cropland soil, revealing their distribution patterns and influencing factors.
  • Establishing a model linking microplastic abundance to cumulative mulching film years, providing a predictive tool.
  • Combining the model with remote sensing data to unveil the regional distribution of microplastics across Xinjiang croplands.

Our findings provide:

  • A deeper understanding of microplastic pollution dynamics in mulching film-based agriculture.
  • A robust method for assessing and predicting microplastic contamination in croplands.
  • Valuable data for informing mitigation strategies and policy decisions.

This study paves the way for effective microplastic management and for examining their environmental impacts in Xinjiang and beyond, safeguarding agricultural productivity and environmental health. Future study efforts are encouraged to examine local and remote impacts of soil microplastics in Xinjiang and beyond.

How to cite: Zhang, Q., Zhang, S., Dong, W., Wang, Z., and Mo, Z.: Cropland Microplastics in Xinjiang: Unveiling Distribution and Impact of Mulching Film Residues, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-2520, https://doi.org/10.5194/egusphere-egu24-2520, 2024.

16:30–16:40
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EGU24-4077
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ECS
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On-site presentation
Gilberto Binda, Stefano Carnati, Margarida Costa, Vladyslava Hostyeva, Eva Leu, Birger Skjelbred, Davide Spanu, Luka Šupraha, Sara Trotta, Christian Vogelsang, and Luca Nizzetto

The presence of plastic litter and microplastics in freshwaters has raised concern about their potential transport and accumulation in water and sediments over time. However, several direct and indirect environmental consequences are still not well understood. In this study, we investigated the role of plastic as a carrier of algal species favouring their dispersal in freshwaters, and we assessed the potential effects on water biodiversity and chemical features in a pilot, laboratory-based study. We simulated an algal community using 5 algal species commonly found in freshwaters and we exposed this community to both pristine and biofouled polypropylene fragments of 5 × 5 × 0.3 mm in size. The biofouled plastic was generated by incubating similar polypropylene fragments with 2 other freshwater algal species, which were different from those in the simulated community. In addition, we evaluated the effect of the dispersal of algae from plastic without the presence of a simulated pelagic community. The experiment lasted 15 days in total. At different time intervals, we assessed: total algal growth and photosynthetic efficiency, algal community composition and the concentration of macronutrients and minor elements in the water. We observed changes in the algal community composition and marked chemical alterations driven by the presence of the biofouled plastics. The presence of pristine plastic, instead, did not show significant changes in the community composition and in the concentration of dissolved elements. The dispersal of algal species from the biofilm on plastic and competitive interactions between the plastic biofilm and the pelagic community were, therefore, likely responsible for the changes in the algal diversity. These results confirmed the hypothesis that plastic can influence dispersal and biodiversity of the algal community. Biofouled plastic from environmental samples and environmental communities selected from natural freshwater bodies will be used in future experiments. This will help to unravel the potential consequences of plastic pollution for ecosystem functioning and microbial biodiversity.

How to cite: Binda, G., Carnati, S., Costa, M., Hostyeva, V., Leu, E., Skjelbred, B., Spanu, D., Šupraha, L., Trotta, S., Vogelsang, C., and Nizzetto, L.: Effects of biofouled plastics on phytoplankton community assembling and water chemistry: pilot study and implications for freshwater environments, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-4077, https://doi.org/10.5194/egusphere-egu24-4077, 2024.

16:40–16:50
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EGU24-8769
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ECS
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Highlight
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On-site presentation
Iulian Pojar, Teodora Baboș, Oana Dobre, and Constantin Dobre

The Danube River, an important pathway connecting the western, central, and eastern Europe, serves as a route for various pollutants that ultimately accumulate in the Danube Delta and the broader Black Sea basin. These historically pristine regions now face escalating pressures from extensive tourism, intense fishing activities, regional conflicts, and inadequate waste disposal across the whole Danube basin. The imbalance in sediment flow, mainly caused by numerous upstream hydropower plants, aside the abovementioned anthropogenic factors, poses a severe threat to the deltaic and coastal ecosystems.

Among the emerging pollutants, litter stands out prominently, with anthropic macro-objects pervading natural environments. Microplastics (MPs) constitute a category of the litter, characterized by solid, petroleum-based items sized between 1 µm and 5 mm. These particles are either preformed within these dimensions or result from the fragmentation of larger plastic debris due to natural weathering. Known for their fast spreading across diverse environments, MPs possess a porous texture that might absorb substantial amounts of various pollutants, significantly impacting the entire food chain, particularly aquatic species.

Given the limited data on MPs pollution in Black Sea coastal areas, the precise impact on the natural environment remains largely uncertain. Furthermore, the correlation between MPs pollution in aquatic environments and the concentration of MPs within mussels and fish has yet to be established. To address these knowledge gaps, our study investigated the abundance of MPs in the water surface layer (average concentration of 0.63 MPs/m³) and in two distinct species: (i) the mackerel - Alosa immaculata – a pelagic fish captured at the Saint Geoge branch mouth of the Danube Delta during inland migration for reproduction, with an average concentration of 11.8 MPs/individual, and (ii) Mytilus galloprovincialis – a filter feeder mollusc collected near the Constanța harbour – with an average concentration of 6.05 MPs/individual.

Our findings indicate that fibers represent the predominant morphology of MPs found in both species, while fragments dominate the surface water layer. Notably, before the tourist season, the distribution of MPs types differs, suggesting potential influences from coastal natural factors such as wind, waves, and currents on the variety of MPs encountered. This research underscores the urgency of further investigations to comprehend the intricate dynamics of MPs pollution in these vital ecosystems and the cascading effects on marine life.

How to cite: Pojar, I., Baboș, T., Dobre, O., and Dobre, C.: Microplastic occurrence in coastal waters and aquatic faunas of the Western Black Sea , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-8769, https://doi.org/10.5194/egusphere-egu24-8769, 2024.

16:50–17:00
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EGU24-8029
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ECS
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On-site presentation
Jonatan Romero-Matos, Francisco Macías, José Miguel Nieto, Laura Sánchez-López, Rafael León, Ricardo Millán-Becerro, and Rafael Pérez-López

The impact of mine waters is currently one of the most severe environmental problems in the water environment. The Odiel River catchment is a clear worldwide example of a river network intensely affected by acid mine drainage, transporting large pollutant loads towards the Ría de Huelva estuary, and ultimately the Atlantic Ocean [1]. The release of acidity and metals, and the longevity of the process, represent a major source of pollution which treatment or possible solutions have been the subject of research in recent years. Prior to the adoption of restoration measures in the region, involving a large economic investment, it was proposed to build a hydrogeochemical model that represents the current situation of the pollution, and serves as a management tool for the Odiel River network. In this sense, its design allows to simulate remediation actions and evaluate their impact on the water quality. The model is based on a set of mixtures modeled with PHREEQC code [2] as analogs to the numerous river confluences. The "MIX" command was used, which enables the mixing two or more aqueous solutions at different mixing ratios. Each ratio theoretically assumes how much each member contributes to the final mixture. Each member is defined as a’ solution with the command "SOLUTION_SPREAD" including the physicochemical parameters and element concentrations, obtained experimentally and in the field. Coupling the "EQUILIBRIUM_PHASES" command includes the equilibrium reactions with Fe and Al mineral phases and the atmosphere. Consequently, each modeled and equilibrated mixture will be mixed again downstream in new confluences until a global modeling of the catchment is achieved. In this way, the model makes it possible to estimate changes in the physicochemical parameters, the evolution of metal concentrations, and variations in the saturation rates of the mineral phases (precipitation, dissolution or equilibrium). This kind of model is a useful tool for simulating reductions in the pollutant loads of sources predicting how real restoration actions will affect the water quality conditions along the Odiel River catchment. The proposed approach could be applied to other real case scenarios where mine waters originate from various sources, mainly different mines, within a complex river network, stablishing itself as an environmental tool for the management of mine water-polluted catchments.

Acknowledgements

This work is part of the I + D + i TRAMPA project (PID2020-119196RB-C21), funded by MCIN/AEI/10.13039/501100011033/. Jonatan Romero-Matos is financed by a FPU program of the Spanish Ministry of Education of Vocational Training (FPU20/04441).

[1] Nieto, J. M., Sarmiento, A. M., Canovas, C. R., Olias, M., & Ayora, C. (2013). Acid mine drainage in the Iberian Pyrite Belt: 1. Hydrochemical characteristics and pollutant load of the Tinto and Odiel rivers. Environmental Science and Pollution Research, 20, 7509-7519.

[2] Parkhurst, D. L., & Appelo, C. A. J. (2013). Description of input and examples for PHREEQC version 3—a computer program for speciation, batch-reaction, one-dimensional transport, and inverse geochemical calculations. US geological survey techniques and methods, 6(A43), 497.

How to cite: Romero-Matos, J., Macías, F., Nieto, J. M., Sánchez-López, L., León, R., Millán-Becerro, R., and Pérez-López, R.: Hydrogeochemical modeling as a tool for the environmental management of mine water polluted river catchments: An application to the Odiel River network (Huelva, Spain), EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-8029, https://doi.org/10.5194/egusphere-egu24-8029, 2024.

17:00–17:10
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EGU24-7953
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ECS
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On-site presentation
Laura Sánchez-López, Jonatan Romero-Matos, Rafael León, Ricardo Millán-Becerro, Rémi Freydier, Francisco Macías, and Rafael Pérez-López

Estuaries are dynamic systems that play a crucial role in the transfer of trace elements from continent to ocean. The Ría de Huelva estuary is formed by the confluence of the Tinto and Odiel rivers, which are severely contaminated by acid mine drainage (AMD), transporting high pollutant loads of sulfates and metal(loid)s to the estuary and ultimately to the Atlantic Ocean. Despite extensive research on this estuary, the behavior of oxyanions has not yet been adequately addressed. This work assesses the variations of the concentration of oxyanion-forming elements such as As, Sb, V, and Mo within the fluvial domain of the Tinto River estuary. Two sampling campaigns were conducted under low river flow, one with a low tidal coefficient (26-30) and the other with a high tidal coefficient (99-102). Dissolved and particulate (>0.45 µm) As, Sb, V, and Mo concentrations were measured in samples of surface water collected by an autosampler Teledyne ISCO with high temporal resolution (hourly) for 24 hours. Additionally, physicochemical parameters were measured for each sample. During both sampling periods, several complete tidal cycles were recorded. The pH and EC values ranged from 4.0 to 6.3 and from 43.2 to 51.9 mS cm-1, respectively, with low tidal coefficient. With high tidal coefficient, the pH and EC values ranged from 4.4 to 7.6 and from 43.7 to 53.0 mS cm-1, respectively. Highest values were recorded during high tide conditions due to greater influence of seawater. Particulate oxyanions proportion displayed a general increase along with increasing pH, being retained by Fe-oxyhydroxisulfate precipitates like schwertmannite as demonstrated in previous research [1]. Data obtained suggest that during high tide with low tidal coefficient, oxyanions remain mainly in the particulate phase (55-100%). Nevertheless, at high tidal coefficient, a significant decrease in the particulate phase proportion is observed when pH is above 6.43 with total concentrations found in the dissolved phase (reaching 100%). This increase in the dissolved phase is probably associated with desorption processes related to the zero-point charge of schwertmannite in circumneutral water environments. During the seawater neutralization of the Tinto River’s acidic waters, when pH values are above 6, the schwertmannite surface becomes negatively charged, and since oxyanions are negatively charged, their desorption is expected [1]. Special attention should be paid to As, Sb, V, and Mo, as they return to solution when precipitates reach pH values above 6.43, contributing to the total amount discharged by the Tinto River, which later reaches the ocean.

Acknowledgments

This work is part of the I + D + i TRAMPA project (PID2020-119196RB-C21), funded by MCIN/AEI/10.13039/501100011033.

[1] Pérez-López, R., Millán-Becerro, R., Basallote, M. D., Carrero, S., Parviainen, A., Freydier, R., Macías, F., Cánovas, C. R. (2023). Effects of estuarine water mixing on the mobility of trace elements in acid mine drainage leachates. Marine Pollution Bulletin, 187, 114491.

How to cite: Sánchez-López, L., Romero-Matos, J., León, R., Millán-Becerro, R., Freydier, R., Macías, F., and Pérez-López, R.: Tracing the behavior of metallic oxyanions in an acid mine drainage polluted estuary (Tinto River estuary, SW Spain), EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-7953, https://doi.org/10.5194/egusphere-egu24-7953, 2024.

17:10–17:20
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EGU24-8888
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On-site presentation
Anna Vancsik, Lili Szabó, László Bauer, Csilla Király, Zsolt Pirger, Attila Csaba Kondor, Gergely Jakab, and Zoltán Szalai

Fluoroquinolone antibiotics are widely used in animal husbandry and human medicine and are therefore released into environmental systems in significant quantities. Because of its targeted antibacterial action, it directly disrupts the soil microbial ecosystem and alters soil carbon fixation. In order to maintain soil microbial communities and prevent groundwater pollution, it is essential to know what physicochemical properties a soil must have to be safe for sewage sludge application and irrigation with treated wastewater. To understand the effects of land use on the adsorption properties of Luvisols, three different land use areas (arable land, grassland, and forest) and two organic matter (OM) pools (fast and slow) were investigated. The soils were separated to a > 53 µm fraction related to the fast OM pool and a < 53 µm fraction containing the slow OM pool, to investigate the physicochemical properties that affect adsorption capacity. Ciprofloxacin, norfloxacin, and ofloxacin were chosen for adsorption experiments because they are widely detected in environmental systems. The effect of land use on adsorption was only observed in the slow pool in the ascending order of arable land, grassland, and forest. Principal component analysis showed that OM content and composition influenced adsorption in the slow pool. However, the adsorption of bulk soils and fast pools is primarily controlled by the physical soil properties rather than by soil OM. These findings indicate that the OM composition of the < 53 µm fraction with the slow pool can determine the adsorption of bulk soils. However, in the present study, this did not affect the adsorption of bulk soils because either 1) the ratio of the slow pool was small, but its adsorption capacity was high, as in the forest, or 2) the ratio of the slow pool was large but its adsorption capacity was low due to its OM composition, as in arable land and grassland. Therefore, irrigation with treated wastewater and sludge discharged on agricultural lands is more likely to leach pollutants into groundwater. Consideration should be given to the disposal of sludge in an area with a high aliphatic soil OM content, where the slow pool rate is high.

This research was supported by the National Research, Development, and Innovation Office (NKFIH), Hungary (project identification number: 2020–1.1.2-PIACI-KFI-2021-00309; 2021–1.2.4-TÉT-2021-00029, and K-142865). Project no. KDP-1015196 has been implemented with the support provided by the Ministry of Culture and Innovation of Hungary from the National Research, Development and Innovation Fund, financed under the KDP-2020 funding scheme. This study has also been supported by the Doctoral Excellence Program (DKOP-23) of the Ministry for Culture and Innovation, Hungary, from the source of the National Research, Development and Innovation Fund.

How to cite: Vancsik, A., Szabó, L., Bauer, L., Király, C., Pirger, Z., Kondor, A. C., Jakab, G., and Szalai, Z.: The impact of land use on the adsorption of fluoroquinolone antibiotics: a study on bulk soils and organic matter pools, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-8888, https://doi.org/10.5194/egusphere-egu24-8888, 2024.

17:20–17:30
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EGU24-9323
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ECS
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On-site presentation
László Bauer, Lili Szabó, Anna Vancsik, Attila Kondor, Gergely Jakab, and Zoltán Szalai

In the last couple of decades, the utilization of different Pharmaceutically Active Compounds (PhACs) significantly has increased. The applications of the treated wastewater (discharge into surface waterbodies, sewage sludge disposal), have resulted that those PhACs world-wildly can be detected in the environment. Due to the negative effects of these PhACs on ecosystems, it is indispensable to analyze their behavior in the soil environment. In the soil solution systems (SSS) the sorption mechanisms of the PhACs are significantly being influenced by various environmental factors like pH, and temperature. In our research, PhACs with different physicochemical properties have been studied such as 17α-ethynylestradiol (EE2), diclofenac-sodium (DFC), and lidocaine (LID). Owing to these facts, the main questions of our research were: (a) How to estimate the Van’t Hoff equation’ parameters in fixed-bed SSS? (b) How does the temperature change affect the intermolecular reactions of the PhACs on the solid/liquid interface in the single and multi-component systems? Single and multicomponent fixed-bed sorption experiments were carried out. All of the sorption experiments have been investigated at 5 different temperatures. The fixed-bed sorption experiments have been performed at the ploughed layer of calcareous, humic sandy soil. The adsorbate-adsorbate and adsorbent-adsorbate interactions have been evaluated by different empirical formulas. To conduct the results of our study, different statistical analyses (2-way ANOVA, Principal Component analysis, regression analysis, and Pearson correlation have been performed. In the scientific literature, the thermodynamical parameters had been carried out in batch experiments. Nevertheless, this way of sorption analysis in an environmental system often overestimates the equilibrium constant (Kc) in the Van’t Hoff equation. Due to this fact, we hypothesized that if the experiment is implemented in a fixed-bed SSS, the real Kc value can be calculated from the real empirical qe value, which could provide the optimal results of the thermodynamical parameters. Our results show that in single-component systems EE2, LID, and DFC have got spontaneous endotherm sorption reactions. While in a multicomponent SSS system, the LID and EE2 had an exothermic enthalpy-driven reaction. Furthermore, in all cases, the Gibbs free energy has been decreased when the temperature was increased.

This research was supported by the National Research, Development, and Innovation Office (NKFIH), Hungary (project identification number: 2020–1.1.2-PIACI-KFI-2021-00309; 2021–1.2.4-TÉT-2021-00029, and K-142865). Project no. KDP-1015196 has been implemented with the support provided by the Ministry of Culture and Innovation of Hungary from the National Research, Development and Innovation Fund, financed under the KDP-2020 funding scheme. This study has also been supported by the Doctoral Excellence Program (DKOP-23) of the Ministry for Culture and Innovation, Hungary, from the source of the National Research, Development and Innovation Fund. And The Hungarian National Research, Development and Innovation Fund OTKA-142865

How to cite: Bauer, L., Szabó, L., Vancsik, A., Kondor, A., Jakab, G., and Szalai, Z.: Fixed-bed thermodynamical analysis of the sorption mechanisms of Pharmaceutically Active Compounds (PhACs) in sandy soil, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-9323, https://doi.org/10.5194/egusphere-egu24-9323, 2024.

17:30–17:40
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EGU24-8943
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ECS
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On-site presentation
Lili Szabó, Anna Vancsik, László Bauer, Attila Csaba Kondor, Gergely Jakab, and Zoltán Szalai

Pharmaceutically active compounds (PhACs) in cultivated areas have become an important issue and have received significant public attention because of their availability to plants during nutrient uptake. This study highlights the effects of low-molecular-weight organic acids (LWMOAs) generated in the root environment on the sorption processes of PhACs in cultivated sandy soil. Sorption experiments are conducted using three PhACs characterised by different physicochemical properties: carbamazepine (CBZ), 17α-ethynylestradiol (EE2), and diclofenac-sodium (DFC). The results suggest that the adsorption of EE2 is more intense than the other two PhACs, whereas DFC and CBZ are primarily dominated by desorption. Additionally, LMWOAs mainly provide additional low-energy adsorption sites for the PhACs, and slight pH changes do no significantly affect the sorption mechanism. During competitive adsorption, the high-energy sites of the adsorbents are initially occupied by EE2 owing to its high adsorption energy. In addition, during multicomponent adsorption, new low-energy binding sites enhance the adsorption of DFC and CBZ. Our results show that LMWOAs promoted the adsorption of PhACs into the root environment, thus rendering PhACs available to plants.

This research was supported by the National Research, Development, and Innovation Office (NKFIH), Hungary (project identification number: 2020–1.1.2-PIACI-KFI-2021-00309; 2021–1.2.4-TÉT-2021-00029, and K-142865). Project no. KDP-1015196 has been implemented with the support provided by the Ministry of Culture and Innovation of Hungary from the National Research, Development and Innovation Fund, financed under the KDP-2020 funding scheme. This study has also been supported by the Doctoral Excellence Program (DKOP-23) of the Ministry for Culture and Innovation, Hungary, from the source of the National Research, Development and Innovation Fund.

How to cite: Szabó, L., Vancsik, A., Bauer, L., Kondor, A. C., Jakab, G., and Szalai, Z.: Effects of root-derived organic acids on sorption of pharmaceuticals in cultivated sandy soil, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-8943, https://doi.org/10.5194/egusphere-egu24-8943, 2024.

17:40–17:50
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EGU24-17428
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ECS
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Virtual presentation
Prasad Padalkar, Parthasarathi Chakraborty, Arup Dey, and Malay Bhattacharya

India has a rich environmental ecosystem, stretching from high-rise mountains to coastal areas. The surge in industrialization and economic growth in the country has imposed a considerable burden on the environment, hindering progress toward sustainable development goals. One critical concern in this context is mercury (Hg) pollution, where special attention is needed. On June 18th 2018, India ratified the Minamata Convention to address Hg pollution. However, a significant data gap exists regarding comprehensive baseline information from different environmental compartments in India, which is crucial for assessing the convention's effects. To bridge this research gap, an effort was made to access Hg distribution and speciation in various environments. For this study, soil and sediments samples were collected from diverse regions: the metropolitan city (Kochi, Kerala, India), agricultural lands (Dhapa, Kolkata), hilly areas (Tea Garden, Darjeeling), and the coastal sediments (collected from continental shelf/slope of the west coast of India). The total soil Hg concentration in metropolitan soil, agricultural soil, and tea garden soil ranged from 16 ± 0.84 µg/kg to 2674 ± 133 µg/kg, 726 ± 36 µg/kg to 2318 ± 115 µg/kg, and 158 ± 7 µg/kg to 9441 ± 472 µg/kg, respectively. Meanwhile, the total Hg concentration in the studied continental shelf sediment samples varied from 8 ± 0.14 µg/kg to 50 ± 2 µg/kg. This result shows that a significantly higher total concentration of Hg in the tea garden soil, whereas lowest Hg concentration were observed in the coastal sediment. Chemical speciation of Hg was carried out using thermo-desorption technique. It was found that the major part of the total Hg was predominantly associated with organic matter in the soil as well as in the coastal sediments. This indicates that organic matter was key host for Hg in soil as well as in coastal sediments. Interestingly, the second-highest fraction in the all types of soil was Hg0, indicating more reduction of Hg in the soil. The elevated Hg0 levels in the soils raises concerns due to its high volatility at ambient temperatures. The evasion of Hg0 from the soil can serve as a significant non-point source of Hg, posing potential risks to individuals living in these areas. Prolonged exposure to this toxic metal could lead to adverse health effects for the local population. Further in the sediments, Hg associated with sulphide was the second dominant Hg fraction, playing crucial role in Hg stability. Overall, these findings not only help to stakeholders and policy makers in addressing Hg pollution, but also contributes to progress towards achieving Sustainable Development Goals.

How to cite: Padalkar, P., Chakraborty, P., Dey, A., and Bhattacharya, M.: Mercury(Hg) Speciation in different environmental compartments of the India: A Thermo-desorption-Driven Approach, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-17428, https://doi.org/10.5194/egusphere-egu24-17428, 2024.

17:50–18:00
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EGU24-17814
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ECS
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On-site presentation
Andreia C. M. Rodrigues, Mariia V. Petrova, Natalia Torres-Rodriguez, Aurelie Dufour, Claudia Cosio, Deny Malengros, Christian Marschal, Gianluca Lazzaro, Manfredi Longo, and Lars-Eric Heimbürger-Boavida

Panarea, an island in the Tyrrhenian Sea, Mediterranean Sea, is distinguished for its hydrothermal vent ecosystems that substantially influence the local biodiversity. While hydrothermal vents are recognised for their mineral-rich composition, the potential release of mercury (Hg), a non-essential metal, into the surrounding environment raises environmental concerns. This study investigates the oxidative stress status and cellular energy allocation of the autochthonous marine gastropod Phorcus turbinatus (Born, 1778), collected from rocky shores at two distinct hydrothermal vents, Bottaro and La Calcara, characterized by different hydrothermal vent activities. Our results show a higher THg input at La Calcara vent (864 pM) when compared to Bottaro (45.9 pM), suggesting exposure by diet. Accordingly, significantly higher levels of oxidative damage, measured as lipid peroxidation (LPO), were observed in gastropods from La Calcara compared to their counterparts from Bottaro. This observation aligns with lower catalase (CAT) activity and total glutathione levels (tGSH) in these gastropods, indicating compromised antioxidant defenses against reactive oxygen species (ROS). No significant differences were observed in energy metabolism when comparing cellular energy allocation (CEA) between snails from the two locations. Nevertheless, gastropods from La Calcara exhibited significantly reduced levels of available sugars, suggesting potential energetic costs of dealing with higher levels of oxidative stress due to increased Hg exposure. Understanding the complex relationships among hydrothermal vent activity, Hg inputs, Hg transfer in food webs, and biota responses provides valuable insights for conservation and management efforts in these unique and fragile ecosystems. Future research should focus on elucidating the long-term effects of Hg exposure at several hydrothermal vent locations, their biodiversity, and ecosystem dynamics, contributing to the broader understanding of metal contamination in marine environments.

How to cite: Rodrigues, A. C. M., Petrova, M. V., Torres-Rodriguez, N., Dufour, A., Cosio, C., Malengros, D., Marschal, C., Lazzaro, G., Longo, M., and Heimbürger-Boavida, L.-E.: Hydrothermal Vents in Panarea, Italy: Investigating Mercury inputs and evaluating Biota Oxidative Stress Status with a focus on Phorcus turbinatus as a Bioindicator of Mediterranean Sea Health, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-17814, https://doi.org/10.5194/egusphere-egu24-17814, 2024.

Posters on site: Mon, 15 Apr, 10:45–12:30 | Hall X1

Display time: Mon, 15 Apr, 08:30–Mon, 15 Apr, 12:30
Chairpersons: Petra Heinz, Maria Dolores Basallote, Carlos Ruiz Cánovas
X1.1
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EGU24-20817
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ECS
Raul Moreno Gonzalez, Luis Barbero, Andrea Celeste Curcio, Rafael León, and Jonatan Romero

One of the major environmental problems caused by mining operations is water pollution. In sulfide mining, pyrite is exposed to atmospheric conditions causing oxidize and release acidity and metals. The water transports these contaminants, producing a leachate known as Acid Mine Drainage (AMD). The Iberian Pyritic Belt (IBP), which belongs the province of Huelva, is very rich in massive sulfide deposits that are mainly composed of pyrite. Mining activity has left numerous abandoned mines with enormous amounts of waste rich in sulfides, including Tharsis mines. Numerous acid leachates emerge from the waste from the Tharsis mines, which have not been active since 2001, and drain to rivers of the area. In the dry season, pollutants precipitate in the form of soluble evaporitic salts that are redissolved with the first important rains of autumn. This redissolution of salts generates a pH decrease and the release of high amounts of contaminants such as Fe, Al, Zn, Mn, As, SO4, Cu, Ni, etc. Remote sensors provide a cost-effective, consistent and accurate approach to monitoring mining pollution. Multispectral and hyperspectral sensors have been widely used due to the distinctive spectral absorption characteristics of minerals. The emerging use of unmanned aerial systems (UAS), such as multicopters coupled with hyperspectral sensors, has become a tool for collecting data at a higher spatial resolution than most aircraft and satellites, resulting in greater accuracy.

To obtain the aerial images, a DJI Matrice 600 Pro octacopter UAS was used with a Headwall Hyperspectral (HS) Coaligned VNIR-SWIR sensor with visible and near infrared range (VNIR; 400-1000 nm) and shortwave infrared range (SWIR; 900-2500 nm) and equipped with a LiDAR to quickly obtain an DSM for georeferencing of the hypercubes. The data obtained have been preprocessed to obtain an orthomosaic with the VNIR and SWIR spectra. The data are processed with ENVI v 5.3.6 and QGIS v 3.26.3 software. Wavelengths from 2001 nm to 2450 nm are selected to identify the minerals that are present in the study area, resulting in an orthomosaic with 76 exploitable bands. MNF and PPI techniques are applied to this orthomosaic to obtain the spectral signatures of the study area. These spectral signatures are compared to the USGS mineral library to identify the minerals present. In this way, 8 minerals are identified: hematite, goethite, jarosite, epsomite, copiapite, illite, clinochlore and chlorite + muscovite. Afterwards, the pixels in the study area are classified and the location of the minerals is obtained. Jarosite, epsomite and copiapite are the most abundant minerals and mainly present in the surroundings of waste leachates. The first rains after summer, evaporitic salts and Fe oxides, hydroxides and hydrosulfates are redissolve and cause a considerable polluting load increase. The surface area occupied by these minerals is 3,861 m2, which represents a high load of pollutants that reach the rivers in the area.

How to cite: Moreno Gonzalez, R., Barbero, L., Curcio, A. C., León, R., and Romero, J.: Assessment of pollutant load in Tharsis mine (Huelva, Spain): A study of evaporitic salts using UAS-Based Hyperspectral, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-20817, https://doi.org/10.5194/egusphere-egu24-20817, 2024.

X1.2
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EGU24-20607
Carlos Ruiz Cánovas

Carlos Ruiz Cánovas1, Manuel Olías1, Francisco Macías1, María Dolores Basallote2, Eduardo Navarrete3 and Juan Mantero4

1Department of Earth Sciences & Research Center on Natural Resources, Health and the Environment. University of Huelva, Campus El Carmen, E-21071, Huelva, Spain manuel.olias@dgyp.uhu.es; carlos.ruiz@dgeo.uhu.es, manuel.olias@dgyp.uhu.es, carlos.ruiz@dgeo.uhu.es, francisco.macias@dgeo.uhu.es

2Department of Ecology and Coastal Management, Institute of Marine Sciences of Andalusia, CSIC, E-11510, Puerto Real, Cádiz, Spain mdolores.basallote@csic.es

3Andalusian Environmental and Water Agency, C/ Johan G. Gutenberg, 1 - Isla de la Cartuja, 41092 Seville, Spain  eduardo.navarrete@juntadeandalucia.es

4Department of Applied Physics II, ETSA, University of Seville, Av Reina Mercedes 2, 41012 Seville, Spain, manter@us.es

 

This work studies the behavior of Uranium (U) and Thorium (Th) in the Tinto River during the hydrological year 2017/2018. The dissolution of surrounding rocks due to extreme acidity conditions, generated during the oxidation of sulfides, induces the release of high concentrations of U and Th into the water. Maximum dissolved concentrations of 57 μg/L of U and 61 μg/L of Th were determined in this study, coinciding with the first precipitation events of the hydrological year due to the washout of evaporitic salts covering the riverbed and mining areas during the dry period, as well as the transport of sulfide oxidation products. Subsequently, a progressive decrease in concentrations was observed, reaching values close to 5 μg/L by February 2018, which are much higher than those found in freshwaters.

With the arrival of intense rains in March and April 2018, a significant decrease in concentrations (<1 μg/L) occurred, primarily due to dilution. Both elements exhibit quasi-conservative behavior due to the low pH values in the river (2.1-4.2), preventing the precipitation of Al mineral phases and the incorporation of U and Th into them. Although the precipitation of Fe mineral phases at these pH values is intense, the adsorption/coprecipitation processes of U and Th onto these phases seem to be limited by the formation of sulfate complexes (Th(SO4)2), ThSO42+, UO2SO4). The transport of U and Th by particulate matter is very limited, although there appears to be a correlation with Al. An increase in concentration of U and Th is observed during the mixing of these acidic waters with ocean waters due mainly to the formation of carbonate complexes which enhances the mobility of U and Th in the estuarine domain.

How to cite: Ruiz Cánovas, C.: Transport of U and Th from a river affected by acid mine drainage (AMD) to the Atlantic Ocean, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-20607, https://doi.org/10.5194/egusphere-egu24-20607, 2024.

X1.3
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EGU24-9035
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ECS
Ricardo Millan-Becerro, Encarnación Ruiz-Agudo, María P. Asta, Sarah Bonilla-Correa, Miguel Burgos Ruiz, and Francesco Santoro

The “Ría de Huelva” estuary (SW Spain) is highly affected by acid mine drainage and phosphate fertilizer industry effluents, which contain high concentrations of dissolved metal(loid)s, some of them of high economic interest such as Rare Earth Elements (REE). These elements are essential for the energy transition as they are used in various applications necessary for the production, transport, and accumulation of electrical energy from renewable sources. However, high dissolved concentrations of REE could have a significant environmental impact on aquatic organisms [1]. This research work focuses on the remediation of REE-laden solutions with different concentrations of these metals, using a sorption strategy with mineral phases such as gypsum (CaSO4·2(H2O)) and brushite (CaHPO4·2(H2O)), where these elements of high economic interest may be concentrated for its potential recovery. The main objectives of this research were to determine: (1) the removal processes of dissolved REEs, as well as (2) the preferential incorporation in the minerals studied. For this purpose, precipitation experiments of REE-rich sulfate and phosphate phases were carried out in the laboratory. The liquid and solid samples resulting from the precipitation experiments were analyzed by atomic emission spectroscopy with inductively coupled plasma (ICP-AES), mass spectrometry with inductively coupled plasma (MS), X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission Fourier transform infrared (FTIR), which allowed us to determine the capacity for REE incorporation by the tested minerals, as well as possible changes in the characteristics of the newly-formed phases. The concentrations of REE in the sulfate and phosphate phases increased progressively as solutions with higher concentrations of these metals were used in the laboratory experiments. However, the removal percentages of REE by gypsum precipitation were noticeably lower than those by brushite precipitation. This could be because brushite has a greater adsorption capacity than gypsum, as both mineral phases have similar crystalline structures and therefore the co-precipitation processes of REE with both minerals should be similar. These results show that the removal of REE from solutions during the precipitation of newly-formed phases could be a viable strategy for the concentration of these valuable elements and the remediation of contaminated waters.

Acknowledgements

This work is part of the I+D+i TRAMPA project (PID2020-119196RB-C21), funded by MCIN/AEI/10.13039/501100011033/.

 

[1] Oral, R., Bustamante, P., Warnau, M., D'Ambra, A., Guida, M., Pagano, G., 2010. Cytogenetic and developmental toxicity of cerium and lanthanum to sea urchin embryos. Chemosphere 81:194–198.

How to cite: Millan-Becerro, R., Ruiz-Agudo, E., Asta, M. P., Bonilla-Correa, S., Burgos Ruiz, M., and Santoro, F.: Remediation of rare earth elements (REE)-rich waters by precipitation of newly-formed phases., EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-9035, https://doi.org/10.5194/egusphere-egu24-9035, 2024.

X1.4
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EGU24-5364
María Dolores Basallote, Rona Giese Miranda, Martin Frank, Manuel Olías, and Carlos Ruiz Cánovas

Metals and metalloids are among the most dispersed hazardous substances released to estuarine systems, which often accumulate within the sediments, contributing to a global problem of pollution in estuaries. In this context, the projected future sea level rise predict the inundation of metal-polluted sediments in littoral areas, which may have serious implications in the mobility of sediment-bound contaminants.

The Tinto River estuary (SW Spain), which is projected to be partially flooded by seawater in 2050 due to the rising sea level, have historically received significant amounts of potentially toxic elements originating from former metal mines, transported to the estuary by the Tinto River.

To estimate the potential release of metal(loid)s associated with seawater flooding, surface sediments were sampled to determine metal concentrations, total carbon content, pH, and particle size distribution. In addition, the contamination factor, geoaccumulation index, and pollution load index were calculated to evaluate metal(loid) pollution. To estimate metal(loid) mobilization upon sea level rise a delimited area of the Tinto River estuary was defined (according to sea level rise projections), and elements mobilization was calculated using values obtained from inundation experiments (Kerl et al., 2023) and sequential extraction methods.

Sediments from the study site turn out to be highly polluted with calculated pollution load indices over 1 and surpassing Spanish guidelines and international sediment quality guidelines , especially for As (300 – 1300 mg/kg), Cu (300 – 3500 mg/kg) and to a lesser extent Zn (100 – 1400 mg/kg) and Cd (0.2 – 5.8 mg/kg). Results show that significant amounts of Fe, Cu, Zn and As (36800, 11200, 1390, 3.22 kg, respectively) can be mobilized under short-term inundations (65 days) related to climate change scenarios predicted for 2050. Under 2100 projections, the mobilization of those metal(loid)s is expected to be further enhanced by the additonal release of large amounts of Fe, as a result of the reductive dissolution of Fe- or Mn-oxyhydroxides, which is mainly attributed to the promotion of reduced conditions in currently oxic sediment layers. These results provide a first estimation of the potential mobilization of potentially toxic elements upon climate change, which is of paramount importance for risk assessment in metal(loid) polluted estuaries worldwide.

How to cite: Basallote, M. D., Miranda, R. G., Frank, M., Olías, M., and Cánovas, C. R.: Potential metal(loid)s mobilization from acid mine drainage-affected sediments under sea level rise projections, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-5364, https://doi.org/10.5194/egusphere-egu24-5364, 2024.

X1.5
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EGU24-5988
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ECS
Leifang Li and Dawen Yang

Extreme climate change can lead to a drastic deterioration in water quality. However, researchers often struggle to find long-term water quality monitoring data, especially at a daily scale, which hinders the understanding of the response relationship between extreme climate, hydrology, and water quality. This study proposes an integrated machine learning framework with physical constraints from various environmental domains such as meteorology and water quantity that can effectively impute a high percentage of missing data and downscale time series data of water quality, producing satisfactory results. Over 78% of the physical water quality variables exhibit NSE (Nash-Sutcliffe efficiency coefficient) values greater than 0.45, and more than 66% of the chemical water quality variables achieve NSE values greater than 0.35. The results of this work demonstrate the effectiveness of the proposed framework as a data augmentation and temporal interpolation tool to enhance the adequacy of water quality monitoring and explore the mechanisms underlying the impact of extreme climate on water quality.

How to cite: Li, L. and Yang, D.: Enhancing Water Quality Monitoring: An Integrated Machine Learning Framework with Physical Constraints for Imputation and Time Series Downscaling, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-5988, https://doi.org/10.5194/egusphere-egu24-5988, 2024.

X1.6
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EGU24-6168
Philipp Böning, Frederik Gäng, Katharina Pahnke, and Olaf Dellwig

The sedimentary database of mercury (Hg) in modern upwelling sediments from the Humboldt and Benguela current systems is sparse, yet this element is a prime indicator of anthropogenic perturbations of the marine realm. Mercury has various natural and anthropogenic sources, occurs in different species, and internal recycling processes before final burial renders the interpretation of the Hg accumulation process challenging. Here, we present data of total Hg (along with Al, P, Zr, organic carbon and Pb, another anthropogenic indicator) for 210Pb-dated continental margin sediments from Peru, Chile and Namibia from within and below their respective oxygen minimum zones (OMZs). All sediments exhibit upcore authigenic enrichments of Hg in the upper 20 - 30 cm, which suggests that Hg has an anthropogenic source, similar to Pb. Moreover, the Hg enrichments are highest off Peru with up to 800 ppb authigenic Hg in the early ‘80s, followed by those off Chile (~ 150 ppb Hg) and Namibia (~ 80 ppb Hg). This is likely due to a high number of industrial and pre-industrial mining sites in Peru, which is less important in Chile and essentially missing in Namibia. The data further suggest that Hg is trapped by organic particles, which settle quickly through O2-deficient waters. In contrast to Pb, which is rapidly removed from the water column at OMZ sites, Hg is also exported to the deep sea environment (> 1000 m water depth below OMZs). This is likely due to recycling processes before final Hg burial. Authigenic Hg enrichments in Peruvian sediments that have negligible authigenic Pb contents suggests the presence of Hg inputs since pre-industrial times (before ~ 1900 AD), which is in line with previous findings from Peruvian lakes and the Galapagos Islands. By contrast, anthropogenic Hg is only visible in near coastal Namibian sediments since the last ~ 70 years. Overall, our data indicate that upwelling sediments are valuable archives for the preservation of anthropogenic signals given the favorable boundary conditions (high productivity, high oxygen deficiency and high sedimentation rates).

How to cite: Böning, P., Gäng, F., Pahnke, K., and Dellwig, O.: Sedimentary mercury cycling in recent upwelling systems, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-6168, https://doi.org/10.5194/egusphere-egu24-6168, 2024.

X1.7
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EGU24-8827
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ECS
Shunichi Kinoshita, Yuri Hashimoto, Azumi Kuroyanagi, and Atsushi Suzuki

There is concern that the increasing pCO2 following the Industrial Revolution Period might lead to ocean acidification, which could affect calcifying organisms in the oceans. Recently, negative emission technology has been attracting attention as an effective countermeasure for greenhouse gas emissions. In the ocean, ocean alkalinization technology is proposed to neutralize acidified oceans and enhance the absorption capacity of CO2 in the oceans. The potential effectiveness of ocean alkalinization technology is also suggested by the history of the Earth. During the Cretaceous period, when pCO2 is interpreted >1,000 ppm, calcifying organisms thrived in the Cretaceous oceans. It is hypothesized that it was due to the total alkalinity (TA) of the seawater being maintained higher, thereby kept the calcium carbonate saturation state at necessary. In this study, we examined this hypothesis as well as attempted to predict the effects of the application of current alkalinization techniques in the ocean on calcifying organisms.

Clonal populations of large benthic foraminifers were cultured in highly alkalinized seawater under high pCO2 conditions, and amounts of calcification (weight and volume) were measured (Group 1: high TA and high pCO2). Specimens taken from same clonal population were kept in modern surface seawater (Group 2: low TA and low pCO2) as a control treatment. The same experiments were also conducted as Group 3 (low TA and high pCO2) to simulate future ocean acidification conditions, and as Group 4 (high TA and low pCO2) to simulate alkalinized ocean under a low pCO2 environment. It was showed significant differences in the amount of calcification in each of the Groups after three months cultivation. The amount of calcification in Group 1 was almost the same as that in the control treatment, confirming the possibility of maintaining the growth of calcifying organisms by alkalinization. Calcification amount in Group 3 was the smallest among all groups, indicating that future ocean acidification may inhibit calcification of large benthic foraminifers. In addition, the calcification rate was the greatest in Group 4, it is indicated that ocean alkalinization may enhance the calcification of the organisms. Finally, these results suggest that the calcium carbonate saturation state of seawater is an important parameter for calcification.

How to cite: Kinoshita, S., Hashimoto, Y., Kuroyanagi, A., and Suzuki, A.: Alkalization of seawater enhances calcification of large benthic foraminifers., EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-8827, https://doi.org/10.5194/egusphere-egu24-8827, 2024.

X1.8
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EGU24-11594
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ECS
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Highlight
Leon Plakolm, Sergio Balzano, Matthias Nagy, Petra Heinz, Daniela Gruber, Katy Schmidt, Martin Stockhausen, Thilo Hofmann, and Michael Lintner

Chemical pollutants, such as heavy metals, are a major threat to marine ecology and biodiversity in the Mediterranean Sea. The Gulf of Naples plays a crucial role in risk assessment and mitigation of waste contamination in the area, as severe anthropogenic pressure originates from local urban and industrial areas and intense maritime traffic. The now defunct ILVA steel plant in Bagnoli, constructed between 1905 and 1910, was a leading contributor of metal pollution in the Gulf of Naples until its shutdown in 1990. In order to evaluate the potentially long-lasting impact of this industrial activity on local foraminiferal communities, as well as the response of individual benthic foraminifera, multiple geochemical and sedimentological analytical techniques were employed and the results compared to a non-impacted reference area; inductively coupled plasma mass spectrometry (ICP-MS) and inductively coupled plasma optical emission spectrometry (ICP-OES) revealed exceptionally high levels of metals in the sediment samples taken in close proximity to the former steel plant. Faunal analysis via stereo microscopy and scanning electron microscopy (SEM) concluded slightly lower biodiversity indices and a lower abundance of living foraminifera in the polluted sample, and the near absence of the otherwise ubiquitous genus Ammonia in the reference area. Energy-dispersive X-ray spectroscopy (EDX) was utilized to determine concentrations of iron within foraminiferal tests and established that all analyzed specimens from the polluted sampling site had elevated quantities of iron in their tests, compared to individuals from the reference sampling site. Based on the findings of this investigation, the metal pollution emitted by the former steel mill is still impacting foraminiferal assemblages and individuals to this day. However, the complex interactions of anthropogenic toxins, benthic microorganisms and the environment are not fully unraveled yet and require further analysis.

How to cite: Plakolm, L., Balzano, S., Nagy, M., Heinz, P., Gruber, D., Schmidt, K., Stockhausen, M., Hofmann, T., and Lintner, M.: The influence of industrial metal pollution on Foraminifera in the Gulf of Naples (Bagnoli), EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-11594, https://doi.org/10.5194/egusphere-egu24-11594, 2024.

X1.9
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EGU24-14211
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ECS
Anna Siems, Tina Sanders, Tristan Zimmermann, Michael E. Wieser, and Daniel Pröfrock

Suspended particulate matter and associated pollutants from the entire North Sea are deposited in the Skagerrak, located between Norway and Denmark. Consequently, the sediments of the Skagerrak play a key role for long-term carbon storage within the North Sea. Due to its location and bathymetry, the bottom sediment redox conditions within the Skagerrak are heterogeneous and cover a wide range from oxic to suboxic conditions. We investigated nitrogen sequestration processes and the mobility of pollutants in these sediments during incubation experiments that simulated oxic and suboxic conditions. Analysis of isotopic fractionation was used as a tool to better understand the nitrogen sequestration pathways (δ15NO3-) and redox conditions (δ98/95Mo).

Typically, incubation experiments last days to weeks but do not cover long-term effects. In contrast, we incubated different zones of three sediment cores with North Sea water for up to twelve months. The sediments originated from locations with (a) mainly iron reduction, (b) mainly manganese reduction and (c) both iron and manganese reduction. After one, three, six and twelve months, we sampled water and sediments from the incubations for various parameters (e.g., trace elements, carbon and nitrogen content, nutrients, δ15NO3-, δ98/95Mo). Under aerobic conditions, the sediments with high organic carbon content (2.78 ± 0.05 %) released up to 33 ± 6 µmol g‑1 NO3- during remineralization, while in anaerobic incubations, these sediments released only up to 4.8 ± 0.8 µmol g-1 NH4+. However, sediments with lower organic carbon contents (1.89 ± 0.05 %) released only 4.8 ± 1.2 µmol g‑1 NO3- and 1.18 ± 0.19 µmol g-1 NH4+, respectively. In combination with trace element concentrations, δ98/95Mo ratios allowed to distinct between different organic matter oxidation pathways. The aerobic incubations released mainly copper, lead and nickel while under  anaerobic conditions, also  cobalt but significantly less copper has been released. Hence, the prevailing oxygen conditions also have a strong impact on the remobilization of e.g., legacy pollutants stored in the sediments. The results of our long-term incubations reveal important biogeochemical processes and indicate that some processes are only traceable at larger timescales applied in this study, but not by incubation durations that are usually applied for biogeochemical studies.

How to cite: Siems, A., Sanders, T., Zimmermann, T., Wieser, M. E., and Pröfrock, D.: Release and turn-over of carbon, nitrogen and metals under oxic and suboxic conditions in long-term incubations of Skagerrak sediments , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-14211, https://doi.org/10.5194/egusphere-egu24-14211, 2024.

X1.10
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EGU24-14624
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Takashi Toyofuku, Yukiko Nagai, Remi Tsubaki, and Kazuhiko Fujita

Biomineralization processes are remarkably varied across the biosphere, yet the foraminifera stands out for their intricate construction of calcium carbonate shells—a phenomenon critical for interpreting paleoceanographic applications. In our research, we delve into the latest observations on the calcification strategy employed by the porcelain-shelled foraminifera Sorites orbiculus (Forsskål in Niebuhr, 1775), offering a reevaluation of the prevailing models of chamber formation. Utilizing focused ion beam scanning electron microscopy (FIB-SEM), we meticulously documented the ultrastructural development of the shell in calcification. Our findings may challenge the traditional vesicle-mediated crystal formation hypothesis, revealing a unique and complex cotton candy-like structure at the calcification site instead.

Simultaneously, pH imaging conducted during chamber formation has disclosed a fascinating pattern of pH elevation that transcends the newly formed chambers, extending to the final stages of calcification. This suggests a more intricate and systemic approach to biomineralization than previously understood. The localized increases in pH not only coincide with the morphological intricacies of the shell but also suggest a remarkable environmental plasticity inherent to S. orbiculus. Our nuanced comprehension of calcification, grounded in precise pH measurements and detailed microstructural observations, illuminates new facets of this species' biomineralization strategy. The insights gleaned here hold profound implications for redefining elemental partitioning and isotopic fractionation in foraminiferal shells and may herald a paradigm shift in our understanding of biomineralization within porcelain foraminifera.

 

How to cite: Toyofuku, T., Nagai, Y., Tsubaki, R., and Fujita, K.: Calcification Strategies in Sorites orbiculus: Insights from Ultrafine Structure Observations and pH Variations, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-14624, https://doi.org/10.5194/egusphere-egu24-14624, 2024.

X1.11
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EGU24-21639
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ECS
Tina Palme, Petra Heinz, Irina Polovodova Asteman, and Matthias Nagy

With the warmest year on record and heating of oceans all over the world, it is of increasing interest how marine organisms adapt to these changing conditions. Benthic foraminifera are important components of marine ecosystems, contributing to biogeochemical cycling and serving as indicators of environmental change. Gaining knowledge of their role in energy and nutrient flows leads to a better understanding of ecosystem functioning. In this study we investigated oxygen respiration rates of the potentially invasive benthic foraminifer Nonionella sp. T1 originating from sediments within the Gullmar Fjord and cultivated in artificial sea water (ASW) in the laboratory at the University of Vienna. Nonionella sp. T1 was incubated at two different temperatures: 12 °C closely resembling natural fjord conditions and 20 °C simulating thermal stress to the foraminifers. Additionally, the influence of light on this species’ oxygen consumption was tested because it is known to harbour kleptoplasts (= functioning chloroplasts from algal food source), but little information exists about kleptoplast potential photosynthetic activity. Prior to the experiment, foraminifers were fed with the living diatom Phaeodactylum tricornutum, which is also used as food source for the culture. A non-invasive method was used to analyze oxygen respiration rates. The method involved placing an Oxygen Sensor Spot in a small, 2.5 ml airtight glass vial filled with ASW alongside the foraminifera. Oxygen concentrations under dark and light conditions and at 12 °C and 20 °C, respectively, were documented using an Oxygen Microsensor. We used a large number (n = 100, triplicates) of cleaned, living specimens. Respiration rates are given in µmol O2/h calculated for biovolume (µm³) which was assessed for each individual using photo microscopy. The measured oxygen respiration rates under dark conditions at 12 °C fall within the upper range of previously observed foraminiferal respiration rates. Lower respiration rates during light exposure indicate oxygen production which is likely related to the activity of kleptoplasts. The pending results of the experiment at 20 °C will show if respiratory activity of Nonionella sp. T1 will increase with temperature and if the efficiency of oxygen production of their kleptoplasts is temperature-dependent.

How to cite: Palme, T., Heinz, P., Polovodova Asteman, I., and Nagy, M.: Investigating the influence of temperature on respiration rates of the benthic foraminifer Nonionella sp. T1, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-21639, https://doi.org/10.5194/egusphere-egu24-21639, 2024.