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1.
J Emerg Manag ; 22(3): 249-260, 2024.
Article in English | MEDLINE | ID: mdl-39017598

ABSTRACT

Ashfall from the April 2021 La Soufrière volcano eruption significantly impacted the Caribbean Island of St. Vincent. Out of all infrastructure sectors, transportation was the most affected across the island, with damages totaling $27.5 million (USD). Removal of ash is a debris management, public health, and disaster concern. This study uses the United States Geological Survey Ash3d model to estimate the thickness of ashfall covering roads, structures, and agricultural lands, totaling 9.4 million ft.3 on roadways, 4.8 million ft.3 on structures, and 147 million ft.3 in agricultural areas. Total ashfall on the island was estimated at 1.3 billion ft.3 Long-term planning and recovery challenges include the remote island location, limited resources, and the existing social and humanitarian needs intensified by the disaster. A staged approach to cleanup, debris management, temporary storage of ash, and sustainable reuse of ash as an aggregate for paving and building materials is proposed. The benefits of new technologies for converting ash into building materials using both off- and on-island systems should be considered for reconstruction materials. Using alternatives to sand mining and developing the adaptive reuse of disaster debris would support long-term recovery and resilience.


Subject(s)
Volcanic Eruptions , Humans , Disaster Planning , Transportation , Construction Materials , Models, Theoretical
2.
Science ; 384(6703): 1429-1435, 2024 Jun 28.
Article in English | MEDLINE | ID: mdl-38935712

ABSTRACT

Knowledge of Cambrian animal anatomy is limited by preservational processes that result in compaction, size bias, and incompleteness. We documented pristine three-dimensional (3D) anatomy of trilobites fossilized through rapid ash burial from a pyroclastic flow entering a shallow marine environment. Cambrian ellipsocephaloid trilobites from Morocco are articulated and undistorted, revealing exquisite details of the appendages and digestive system. Previously unknown anatomy includes a soft-tissue labrum attached to the hypostome, a slit-like mouth, and distinctive cephalic feeding appendages. Our findings resolve controversy over whether the trilobite hypostome is the labrum or incorporates it and establish crown-group euarthropod homologies in trilobites. This occurrence of moldic fossils with 3D soft parts highlights volcanic ash deposits in marine settings as an underexplored source for exceptionally preserved organisms.


Subject(s)
Arthropods , Fossils , Volcanic Eruptions , Animals , Arthropods/anatomy & histology , Arthropods/classification , Fossils/anatomy & histology , Morocco
3.
J Environ Manage ; 365: 121616, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38941854

ABSTRACT

Volcanic eruption is associated with the release of large volumes of pollutants in the environment, which can pose a risk to humans and other living organisms. The elemental and radioisotope composition of ash released during the Shiveluch Volcano eruption in 2023 was analyzed using ICP-MS and low-background gamma spectrometry. The ash consisted of 59% SiO2, 16.7% Al2O3, 5.3% CaO, 4.6 % Na2O, 4.5% Fe2O3, 1.4% K2O, 0.48% TiO2, 0.17% P2O5, 0.15% S, 0.078% MnO and 44 trace elements. Hazard Quotient and Hazard Index were calculated in order to evaluate the potential health risks to children and adults due to exposure to contaminants via inhalation, ingestion, and dermal contact. All values were below the unit, indicating a low probability of non-carcinogenic and cancerogenic risk occurrence in target groups. The average activity concentrations of the natural radionuclides were 350, 12.4 and 4.84 Bq/kg for 40K, 226Ra and 232Th. Radiological indices, including external and internal risk assessment, radium equivalent activity, annual effective dose, gamma index, and excess lifetime cancer risk were calculated to estimate the radiological hazard for the population. The values of all indices were below the recommended safety limits, indicating a low level of hazard for the exposed population.


Subject(s)
Metals , Radioisotopes , Volcanic Eruptions , Humans , Metals/analysis , Radioisotopes/analysis , Radium/analysis , Risk Assessment , Thorium/analysis
4.
Proc Natl Acad Sci U S A ; 121(26): e2321068121, 2024 Jun 25.
Article in English | MEDLINE | ID: mdl-38885390

ABSTRACT

An often-overlooked question of the biodiversity crisis is how natural hazards contribute to species extinction risk. To address this issue, we explored how four natural hazards, earthquakes, hurricanes, tsunamis, and volcanoes, overlapped with the distribution ranges of amphibians, birds, mammals, and reptiles that have either narrow distributions or populations with few mature individuals. To assess which species are at risk from these natural hazards, we combined the frequency and magnitude of each natural hazard to estimate their impact. We considered species at risk if they overlapped with regions where any of the four natural hazards historically occurred (n = 3,722). Those species with at least a quarter of their range subjected to a high relative impact were considered at high risk (n = 2,001) of extinction due to natural hazards. In total, 834 reptiles, 617 amphibians, 302 birds, and 248 mammals were at high risk and they were mainly distributed on islands and in the tropics. Hurricanes (n = 983) and earthquakes (n = 868) affected most species, while tsunamis (n = 272), and volcanoes (n = 171) affected considerably fewer. The region with the highest number of species at high risk was the Pacific Ring of Fire, especially due to volcanoes, earthquakes, and tsunamis, while hurricane-related high-risk species were concentrated in the Caribbean Sea, Gulf of Mexico, and northwestern Pacific Ocean. Our study provides important information regarding the species at risk due to natural hazards and can help guide conservation attention and efforts to safeguard their survival.


Subject(s)
Biodiversity , Extinction, Biological , Animals , Birds , Mammals , Reptiles , Earthquakes , Cyclonic Storms , Tsunamis , Amphibians , Volcanic Eruptions , Natural Disasters
5.
Environ Geochem Health ; 46(7): 237, 2024 Jun 07.
Article in English | MEDLINE | ID: mdl-38849684

ABSTRACT

This study presents the first data on REY (Rare Earth Elements plus Yttrium) in the aquifer of Mount Etna (Sicily, Italy). Patterns normalized to chondrites indicate strong water-rock interaction, facilitated by a slightly acidic pH resulting from the dissolution of magma-derived CO2. REY patterns provide insights into the processes of both mineral dissolution and the formation of secondary phases. The relative abundance of light to heavy rare earth elements is compatible with the prevailing dissolution of ferromagnesian minerals (e.g., olivine or clinopyroxenes), reinforced by its strong correlation with other proxies of mineral dissolution (e.g., Mg contents). Pronounced negative Ce anomalies and positive Y anomalies demonstrate an oxidizing environment with continuous formation of secondary iron and/or manganese oxides and hydroxides. The Y/Ho fractionation is strongly influenced by metal complexation with bicarbonate complexes, a common process in C-rich waters. In the studied system, the measured REY contents are always below the limits proposed by Sneller et al. (2000, RIVM report, Issue 601,501, p. 66) for surface water and ensure a very low daily intake from drinking water.


Subject(s)
Groundwater , Metals, Rare Earth , Metals, Rare Earth/analysis , Metals, Rare Earth/chemistry , Groundwater/chemistry , Sicily , Environmental Monitoring , Volcanic Eruptions , Yttrium/chemistry , Water Pollutants, Chemical/analysis
6.
Sci Total Environ ; 944: 173915, 2024 Sep 20.
Article in English | MEDLINE | ID: mdl-38871328

ABSTRACT

The 2021 Tajogaite eruption in La Palma (Canary Islands, Spain) emitted vast volumes of lava during 85 days, which reached the ocean in several occasions at the western flank of the island. Most of these flows merged to create a primary lava delta, covering an area of 48 ha, with an additional 30 ha underwater. Here we characterize the effects of the lava-seawater interaction on the surrounding marine environment. The area was sampled during two multidisciplinary oceanographic cruises: the first one comprised the days before the lava reached the ocean and after the first contact; and the second took place a month later, when the lava delta was already formed but still receiving lava inputs. Physical-chemical anomalies were found in the whole water column at different depths up to 300 m in all measured parameters, such as turbidity (+9 NTU), dissolved oxygen concentration (-17.17 µmol kg-1), pHT25 (-0.1), and chlorophyll-a concentration (-0.33 mg m-3). Surface temperature increased up to +2.3 °C (28.5 °C) and surface salinity showed increases and decreases of -1.01 and +0.70, respectively, in a radius of 4 km around the lava delta. In the water column, the heated waters experimented a lava-induced upwelling, bringing deeper, nutrient-rich waters to shallower depths; however, this feature did not trigger any phytoplankton bloom. In fact, integrated chlorophyll-a showed an abrupt decrease of -41 % in just two days and -69 % a month later, compared to prior conditions. The chlorophyll-a depletion reached a distance larger than 2.5 km (not delimited).


Subject(s)
Chlorophyll , Seawater , Seawater/chemistry , Spain , Chlorophyll/analysis , Environmental Monitoring , Volcanic Eruptions , Chlorophyll A , Salinity , Phytoplankton
7.
Environ Sci Pollut Res Int ; 31(26): 38465-38484, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38806981

ABSTRACT

The bioaccumulation of lead in soil poses a significant human health risk. The solidification/stabilization (S/S) technique, employing binders like Portland cement or lime, is a common method for remediating lead-contaminated soil. However, cement production has adverse environmental impacts, prompting the exploration of eco-friendly alternatives like alkali-activated materials (AAMs). This study assesses AAM efficacy in the S/S of lead-contaminated soil. The effects of several factors, including varying amounts of volcanic ash (VA), lead concentration, curing temperatures, and curing times are investigated. Unconfined compressive strength (UCS), toxicity characteristic leaching procedure test (TCLP), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and field emission scanning electron microscope-energy-dispersive spectroscopy-mapping analyses (FESEM/EDS/mapping) analyses are used to study the specimens. The findings indicated a substantial increase in the UCS of lead-contaminated soil treated with 15% VA (under oven curing (OC) conditions), and 10% VA (under ambient curing (AC) conditions) exhibited remarkable increases of up to 600% and 458%, respectively. Moreover, the leaching of Pb2+ ions from samples contaminated with 10,000 mg/kg (under OC conditions) and 2500 mg/kg (under AC conditions) experienced significant reductions of 87% (from 135.14 to 13.36 ppm) and 91% (from 26.32 to 2.21 ppm), respectively. The S/S process in these samples operated through three primary mechanisms of chemical bonding, physical encapsulation, and the formation of insoluble silicate. The formation of N-A-S-H and hydroxy sodalite structures played a vital role in facilitating these mechanisms. Therefore, alkali-activated VA demonstrated excellent performance in the remediation of lead-contaminated soil.


Subject(s)
Alkalies , Lead , Soil Pollutants , Soil , Lead/chemistry , Soil Pollutants/chemistry , Soil/chemistry , Alkalies/chemistry , Volcanic Eruptions , X-Ray Diffraction , Environmental Restoration and Remediation/methods
8.
Proc Natl Acad Sci U S A ; 121(23): e2312173121, 2024 Jun 04.
Article in English | MEDLINE | ID: mdl-38805287

ABSTRACT

The year 2021 marked a decade of holopelagic sargassum (morphotypes Sargassum natans I and VIII, and Sargassum fluitans III) stranding on the Caribbean and West African coasts. Beaching of millions of tons of sargassum negatively impacts coastal ecosystems, economies, and human health. Additionally, the La Soufrière volcano erupted in St. Vincent in April 2021, at the start of the sargassum season. We investigated potential monthly variations in morphotype abundance and biomass composition of sargassum harvested in Jamaica and assessed the influence of processing methods (shade-drying vs. frozen samples) and of volcanic ash exposure on biochemical and elemental components. S. fluitans III was the most abundant morphotype across the year. Limited monthly variations were observed for key brown algal components (phlorotannins, fucoxanthin, and alginate). Shade-drying did not significantly alter the contents of proteins but affected levels of phlorotannins, fucoxanthin, mannitol, and alginate. Simulation of sargassum and volcanic ash drift combined with age statistics suggested that sargassum potentially shared the surface layer with ash for ~50 d, approximately 100 d before stranding in Jamaica. Integrated elemental analysis of volcanic ash, ambient seawater, and sargassum biomass showed that algae harvested from August had accumulated P, Al, Fe, Mn, Zn, and Ni, probably from the ash, and contained less As. This ash fingerprint confirmed the geographical origin and drift timescale of sargassum. Since environmental conditions and processing methods influence biomass composition, efforts should continue to improve understanding, forecasting, monitoring, and valorizing sargassum, particularly as strandings of sargassum show no sign of abating.


Subject(s)
Biomass , Sargassum , Sargassum/chemistry , Ecosystem , Jamaica , Seasons , Volcanic Eruptions
10.
Nat Commun ; 15(1): 3596, 2024 Apr 27.
Article in English | MEDLINE | ID: mdl-38678037

ABSTRACT

The long-term effects of the Central Atlantic Magmatic Province, a large igneous province connected to the end-Triassic mass-extinction (201.5 Ma), remain largely elusive. Here, we document the persistence of volcanic-induced mercury (Hg) pollution and its effects on the biosphere for ~1.3 million years after the extinction event. In sediments recovered in Germany (Schandelah-1 core), we record not only high abundances of malformed fern spores at the Triassic-Jurassic boundary, but also during the lower Jurassic Hettangian, indicating repeated vegetation disturbance and stress that was eccentricity-forced. Crucially, these abundances correspond to increases in sedimentary Hg-concentrations. Hg-isotope ratios (δ202Hg, Δ199Hg) suggest a volcanic source of Hg-enrichment at the Triassic-Jurassic boundary but a terrestrial source for the early Jurassic peaks. We conclude that volcanically injected Hg across the extinction was repeatedly remobilized from coastal wetlands and hinterland areas during eccentricity-forced phases of severe hydrological upheaval and erosion, focusing Hg-pollution in the Central European Basin.


Subject(s)
Extinction, Biological , Ferns , Fossils , Geologic Sediments , Mercury , Mercury/analysis , Geologic Sediments/chemistry , Germany , Volcanic Eruptions , Mutagenesis , Climate , Spores
11.
J Hazard Mater ; 470: 134229, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38581875

ABSTRACT

Total alpha and beta activities and Rn-222 concentrations were determined in water from different sections of seven aqueducts belonging to the water supply system of Campania region (Italy), known worldwide for its volcanism. Statistical analysis was performed on data to account for their variability across the aqueduct sections, and results were discussed considering the geology of reservoirs, the potential mixing processes occurring along the pipe network, the building/constituting materials of the aqueduct sections, and the integrity of the infrastructure. Guidelines proposed by Italian and international regulation entities were considered to determine if total alpha and beta activities and Rn-222 concentrations found at the taps of the different aqueducts should be considered detrimental to public health. Based on a deterministic and a stochastic approach, a health risk assessment was also tested for Rn-222, assuming direct ingestion and showering as potential exposure pathways. Results showed that applying guidelines returned an absence of hazard, whereas risk assessment returned a high probability of exposure to unacceptable Rn-222 doses for some aqueducts. Beyond the usefulness of obtained results to plan actions to improve the safety of drinking water in Campania, our outcomes represent a warning for bodies dealing with public health at any level: the use of guidelines can bring an underestimation of the risks exerted by the exposure to Rn-222 on human health. Further, using a probabilistic approach in risk assessment accounting for uncertainty can favor risk forecasts based on more "realistic" scenarios.


Subject(s)
Drinking Water , Water Supply , Italy , Humans , Risk Assessment , Drinking Water/analysis , Water Pollutants, Radioactive/analysis , Volcanic Eruptions
12.
Enferm. glob ; 23(74): 1-13, abr.2024. tab
Article in Spanish | IBECS | ID: ibc-232283

ABSTRACT

Objetivo: Este estudio tiene como objetivo determinar el estrés durante la pandemia de COVID-19 y afrontar las erupciones volcánicas y analizar los factores relacionados. Métodos: Esta investigación fue de tipo observacional analítica cuantitativa con un diseño transversal. El número de muestras fue de 352 pacientes mediante la técnica de muestreo accidental. El instrumento de investigación utiliza la escala de estrés percibido (PSS) -10 ítems y la escala de estrés COVID-19. Para el análisis de los datos se utilizaron las pruebas Kendal Tau y Chi-Cuadrado. Resultados: La mayoría de los encuestados experimentaron estrés leve durante la pandemia de COVID-19 (66,2%) y estrés moderado al lidiar con erupciones volcánicas (98,9%). Las variables relacionadas con el estrés durante una pandemia fueron género (p.017), educación (p.027), ingresos (p<.001) y distancia desde casa hasta la cima del volcán (p<0.036), mientras que las relacionadas con el estrés que enfrentan las erupciones volcánicas es sólo una experiencia de desastre de entrenamiento (p.033). Conclusiones: El estudio encontró que el nivel de estrés al enfrentar una erupción volcánica era mayor que durante la pandemia de COVID-19. El género, la educación, los ingresos y la distancia desde el hogar hasta la cima de un volcán están relacionados con el estrés durante una pandemia. Al mismo tiempo, la experiencia de la formación en desastres fue el único factor asociado con el estrés al afrontar las erupciones volcánicas. (AU)


Primary Goal: This study is to determine stress during the COVID-19 pandemic and dealing with volcanic eruptions and analyze the related factors. Methods: This research was an analytic observational quantitative with a cross-sectional design. The number of samples was 352 patients using the accidental sampling technique. The research instrument uses the Perceived stress scale (PSS)-10 items and the COVID-19 Stress Scale. Kendal Tau and Chi-Square tests were used for data analysis. Results: Most respondents experienced mild stress during the COVID-19 pandemic (66.2%) and moderate stress when dealing with volcanic eruptions (98.9%). Variables related to stress during a pandemic were gender (p.017), education (p.027), income (p<.001), and distance from home to the top of the volcano (p<0.036), while those related to the stress faced Volcanic eruptions are just a training disaster experience (p.033). Conclusions: The study found that the stress level of facing a volcanic eruption was higher than during the COVID-19 pandemic. Gender, education, income, and distance from home to the top of a volcano are related to stress during a pandemic. At the same time, the experience of disaster training is the only factor associated with stress in dealing with volcanic eruptions. (AU)


Subject(s)
Humans , Disasters , Stress Disorders, Traumatic , Volcanic Eruptions , Gender Identity , Education
13.
Prehosp Disaster Med ; 39(2): 230-231, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38486463

ABSTRACT

BACKGROUND: Volcanic eruption is one of the most common disasters in Indonesia. One of the most fatal volcanic eruptions in Indonesia in 2023 was the eruption of Mount Marapi in West Sumatra. This caused a psychological impact on the survivors and families of the victims who died. PROBLEM: Psychological interventions are usually only provided to survivors. It is very rare to find psychosocial assistance provided to the families of victims who died, even though they also experience acute and prolonged mental health disorders, such as trauma and even depression. So, we offer the idea of remembrance therapy and reading the Qur'an to restore the mental health of the families of the deceased victims. CONCLUSION: Dhikr and Qur'an recitation therapy fosters sincerity, patience, and self-acceptance so as to restore mental health in the families of the victims of the Mount Marapi eruption. The therapy serves as a calming factor for the soul because it contains various wisdoms for the calamities experienced. The whole series of therapy is closed with prayer as a form of surrendering the soul to God.


Subject(s)
Volcanic Eruptions , Humans , Indonesia , Family/psychology , Male , Female , Mental Health
15.
Sci Total Environ ; 925: 171825, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38513852

ABSTRACT

Carbon dioxide (CO2) is a primary greenhouse gas that has experienced a surge in atmospheric concentration due to human activities and lifestyles. It is imperative to curtail atmospheric CO2 levels promptly to alleviate the multifaceted impacts of climate warming. The soil serves as a natural reservoir for CO2 sequestration. The scientific premise of this study is that CO2 sequestration in agriculturally relevant, organically-deficient saline soil can be achieved by incorporating alkaline earth silicates. Volcanic ash (VA) was used as a soil amendment for CO2 removal from saline soil by leveraging enhanced silicate rock weathering (ERW). The study pursued two primary objectives: first, we aimed to evaluate the impact of various doses of VA, employed as an amendment for organically-deficient soil, on the growth performance of key cultivated crops (sorghum and mung bean) in inland saline-alkaline agricultural regions of northeastern China. Second, we aimed to assess alterations in the physical properties of the amended soil through mineralogical examinations, utilizing X-ray diffraction (XRD) and scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM-EDS) analyses, quantifying the increase in inorganic carbon content within the soil. In the potting tests, mung bean plant height exhibited a noteworthy increase of approximately 41 % with the addition of 10 % VA. Sorghum plant height and aboveground and belowground biomass dry weights increased with VA application across all tested doses. At the optimal VA application rate (20 %), the sorghum achieved a CO2 sequestration rate of 0.14 kg CO2·m-2·month-1. XRD and SEM-EDS analyses confirmed that the augmented inorganic carbon in the VA-amended soils stemmed primarily from calcite accumulation. These findings contribute to elucidating the mechanism underlying VA as an amendment for organically-deficient soils and provide an effective approach for enhancing the carbon sink capacity of saline soils.


Subject(s)
Soil , Sorghum , Humans , Soil/chemistry , Carbon Dioxide/analysis , Volcanic Eruptions , Agriculture , Weather , Edible Grain/chemistry , Carbon Sequestration , Silicates
17.
Environ Health ; 23(1): 19, 2024 Feb 13.
Article in English | MEDLINE | ID: mdl-38350940

ABSTRACT

BACKGROUND: The eruption of the Tajogaite volcano began on the island of La Palma on September 19, 2021, lasting for 85 days. This study aims to present the design and methodology of the ISVOLCAN (Health Impact on the Population of La Palma due to the Volcanic Eruption) cohort, as well as the preliminary findings from the first 1002 enrolled participants. METHODS: A prospective cohort study was conducted with random selection of adult participants from the general population, with an estimated sample size of 2600 individuals. The results of the first 857 participants are presented, along with a group of 145 voluntary participants who served as interveners during the eruption. Data on epidemiology and volcano exposure were collected, and participants underwent physical examinations, including anthropometry, blood pressure measurement, spirometry, and venous blood extraction for toxicological assessment. RESULTS: In the general population (n = 857), descriptive analysis revealed that the participants were mostly middle-aged individuals (50.8 ± 16.4), with a predominance of females. Before the eruption, the participants resided at a median distance of 6.7 km from the volcano in the Western region and 10.9 km in the Eastern region. Approximately 15.4% of the sample required evacuation, whose 34.8% returning to their homes on average after 3 months. A significant number of participants reported engaging in daily tasks involving cleaning of volcanic ash both indoors and outdoors. The most reported acute symptoms included ocular irritation, insomnia, mood disorders (anxiety-depression), and respiratory symptoms. Multivariate analysis results show that participants in the western region had a higher likelihood of lower respiratory tract symptoms (OR 1.99; 95% CI:1.33-2.99), depression and anxiety (OR 1.95; 95% CI:1.30-2.93), and insomnia (OR 2.03; 95% CI:1.33-3.09), compared to those in the eastern region. CONCLUSION: The ongoing follow-up of the ISVOLCAN cohort will provide valuable insights into the short, medium, and long-term health impact related to the material emitted during the Tajogaite eruption, based on the level of exposure suffered by the affected population.


Subject(s)
Disasters , Sleep Initiation and Maintenance Disorders , Adult , Middle Aged , Female , Humans , Male , Prospective Studies , Inflammation , Volcanic Eruptions/adverse effects
19.
Sci Total Environ ; 912: 168694, 2024 Feb 20.
Article in English | MEDLINE | ID: mdl-38007126

ABSTRACT

Coral reefs, which are among the most productive ecosystems on earth, are in global decline due to rapid climate change. Volcanic activity also results in extreme environmental changes at local to global scales, and may have significant impacts on coral reefs compared to other natural disturbances. During explosive eruptions, large amounts of volcanic ash are generated, significantly disrupting ecosystems close to a volcano, and depositing ash over distal areas (10s - 1000s of km depending on i.a. eruption size and wind direction). Once volcanic ash interacts with seawater, the dissolution of metals leads to a rapid change in the geochemical properties of the seawater column. Here, we report the first known effects of volcanic ash on the physiology and elemental cycling of a symbiotic scleractinian coral under laboratory conditions. Nubbins of the branching coral Stylophora pistillata were reared in aquaria under controlled conditions (insolation, temperature, and pH), while environmental parameters, effective quantum yield, and skeletal growth rate were monitored. Half the aquaria were exposed to volcanic ash every other day for 6 weeks (250 mg L-1 week-1), which induced significant changes in the fluorescence-derived photochemical parameters (ΦPSII, Fv/Fm, NPQ, rETR), directly enhanced the efficiency of symbiont photosynthesis (Pg, Pn), and lead to increased biomineralization rates. Enhancement of symbiont photosynthesis is induced by the supply of essential metals (Fe and Mn), derived from volcanic ash leaching in ambient seawater or within the organism following ingestion. The beneficial role of volcanic ash as an important micronutrient source is supported by the fact that neither photophysiological stress nor signs of lipid peroxidation were detected. Subaerial volcanism affects micronutrient cycling in the coral ecosystem, but the implication for coral ecophysiology on a reef scale remains to be tested. Nevertheless, exposure to volcanic ash can improve coral health and thus influence resilience to external stressors.


Subject(s)
Anthozoa , Trace Elements , Animals , Anthozoa/physiology , Ecosystem , Volcanic Eruptions , Biomineralization , Coral Reefs
20.
Environ Sci Pollut Res Int ; 31(5): 7058-7072, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38155312

ABSTRACT

In the eruptive event of Tajogaite (2021) in La Palma, Canary Islands, large quantities of volcanic ash were accumulated, affecting the local environment and urban areas. In this study, volcanic ash sampled from urban areas (catalogued as municipal waste (20 03 03) by the European Wastes Catalogue) were converted into zeolites by hydrothermal synthesis at 100 °C with previous alkaline fusion at 550 °C with distilled water. During this process, new phases of zeolite principally type X and sodalite have been identified by XRD at 2 h of incubation. These zeolites, with the course of incubation time, present competitive processes where the transformation into sodalite develops after 24 h as the predominant phase. The synthesized zeolitic material presents a high concentration as impurities in Fe2O3 (13.70 wt%), Na2O (12.70 wt%), CaO (11.65 wt%), and TiO2 (3.89 wt%) coming from the volcanic ash and NaOH introduced in the synthesis methodology. These impurities impart different physicochemical capabilities to the zeolitic material. The application of zeolites obtained in a preliminary fluoride adsorption experiment with volcanic leachate water rich in fluoride has been tested in a novel way. Removal efficiencies of 41.4% at acidic pH (5.77) have been obtained with 2 g L-1 adsorbent zeolitic material doses. A value-added material is obtained and applied in a preliminary way to solve a problem generated by the volcanic ash itself, allowing the End of Waste status and meeting different objectives of the sustainable development goals of the UN Agenda 2030.


Subject(s)
Coal Ash , Zeolites , Fluorides , Spain , Volcanic Eruptions , Water , Adsorption
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