Person: García Lorenzo, María De La Luz
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First Name
María De La Luz
Last Name
García Lorenzo
Affiliation
Universidad Complutense de Madrid
Faculty / Institute
Ciencias Geológicas
Department
Mineralogía y Petrología
Area
Petrología y Geoquímica
Identifiers
61 results
Search Results
Now showing 1 - 10 of 61
Item Instrumental modification intended to save time, and volumes of sample and reagent solutions, in the atomic fluorescence spectrometric determination of mercury(Analytical and bioanalytical chemistry, 2007) Pérez Sirvent, Carmen; Martínez Sánchez, María José; García Lorenzo, María De La Luz; López García, Ignacio; Hernández Córdoba, ManuelUse of small membrane pumps, instead of peristaltic pumps, to introduce sample and reagent solutions into the spectrometer has several advantages in atomic fluorescence spectrometric determination of mercury. This simple modification results in a substantial saving in the time required for the measurements and so 90% of reagent solution volumes and 95% of sample solution volumes are saved, with a consequent decrease in the volume of waste generated. The sampling frequency is almost tripled, with no deterioration in sensitivity, which is similar to that obtained by use of peristaltic pumps. The relative standard deviation for ten consecutive measurements of a 1 μg L-1 mercury solution was approximately 2%.Item Metal-contaminated soil remediation by using sludges of the marble industry: Toxicological evaluation(Environment international, 2007) Pérez Sirvent, Carmen; García Lorenzo, María De La Luz; Martínez Sánchez, María José; Navarro, M. C.; Marimón, Jorge; Bech, JaumeThe major risks due to metal pollution of sediments consist of leaching to groundwater and potential toxicity to animals and/or plants. The objective of this study was to evaluate by means of an ecotoxicological approach the effects of the addition of cutting marble sludges on the mobile metal fraction of sediments polluted with heavy metals. The study was carried out on two sediments derived from mining activities in Portman Bay (SE, Spain) polluted by heavy metals. These sediments were mixed with sludges left after the cutting of marble. The results obtained by leaching experiments showed that the addition of marble cutting sludge, consisting mainly of carbonates, to a heavy-metal polluted sediment produces a decrease of available metal forms. The carbonate content seems to play a role in chemical stabilisation of metals and in a decrease of toxicity of sediments. The leached solutions have a non-toxic effect. The mild remediation by addition of sludge has moreover effects to long term.Item Geogenic distribution of Arsenic (As) and Antimony (Sb) in soils of the Murcia Region in Spain(Environmental forensics, 2015) García Lorenzo, María De La Luz; Martínez-Sánchez, María José; Pérez-Sirvent, Carmen; López-Sánchez, Joaquín; Molina-Ruiz, José; Tudela, Mari LuzThe objective of this study was to determine the As and Sb contents in soils from the Murcia Region of Spain and the possible relationship between the mineralogical composition, soil properties, and As and Sb concentrations. In this study, 490 samples were selected from areas with different characteristics in order to study As and Sb variability. Results show that As and Sb concentrations are positively correlated with the phyllosilicate and quartz content but negatively correlated with the calcite content. The generic reference level (GRL) for these elements was determined according to the Spanish legislation. Established GRL values vary according to the established mineralogical groups, suggesting that GRL has to be determined considering the lithological characteristics of the study areaItem Synthesis of zeolites from volcanic ash (Tajogaite, Spain) for the remediation of waters contaminated by fluoride(2023) Martínez del Pozo, Iker; Esbrí Víctor, José María; García Lorenzo, María De La Luz; López De Andrés, María SolIn 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.Item Categorization of Mining Materials for Restoration Projects by Means of Pollution Indices and Bioassays(Minerals, 2023) Ferri Moreno, Inmaculada; Barquero Peralbo, Jose Ignacio; Andreu Sánchez, Óscar; Higueras, Pablo; Roca Pérez, Luis; García Lorenzo, María De La Luz; Esbrí Víctor, José MaríaSulfide mining wastes may lead to severe environmental and human health risks. This study aims to use geochemical and ecotoxicological indicators for the assessment of the ecological risks of potentially toxic elements (PTEs) in the San Quintín mining group to categorize wastes prior to mining restoration. Ecotoxicity was evaluated using crustacean (Dahpnia magna, Thamnocephalus platyurus) and algae (Raphidocelis subcapitata) bioassays. The geochemical and mineralogical results suggested that the mining residues underwent intense weathering processes, with active processes of acidity generation and metal mobility. Total PTEs concentrations indicated that the mining materials were extremely polluted, with Pb, Zn and Cd geoaccumulation index (Igeo) values higher than 5 in more than 90% of the samples. The pollution load index (PLI) showed average values of 18.1, which classifies them as very highly polluted. The toxicity tests showed a higher toxicity for plants than crustaceans, being the highest values of toxicity related to toxic elements (Pb, Cd and Zn), electrical conductivity and to pH. This paper presents for the first time the combination of indices in the categorization of mining waste prior to its restoration. The combination of them has made it possible to categorize the waste and adapt the restoration and remediation procedures.Item Impact of climate risk materialization and ecological deterioration on house prices in Mar Menor, Spain(Scientific reports, 2023) Lamas Rodríguez, Matías; García Lorenzo, María De La Luz; Medina Magro, Manuel; Pérez-Quirós, GabrielThe frequency and severity of extreme events related to climate change have intensified worldwide in the last decades. It is documented that increasing extreme rainfall and flooding cause more nutrient runoff into waterbodies, initiating numerous harmful algal bloom (HAB) events, especially in fragile ecosystems. We analyze the dramatic economic damage of one of these episodes in Mar Menor, the largest salt-water lagoon in Europe. We show that when the public perceived the severity of environmental degradation, the return on housing investment was 43% lower in the surroundings than in similar neighboring zones 6 years after the HAB (2015). This represents a loss in housing wealth of more than 4000 million euros, around ten times the gains of changing from dry-farming to irrigated crops, which makes this ecosystem fragile. Hence, we quantify some of the economic consequences of ecological deterioration linked to episodes of Global Climate Change.Item Síntesis de zeolitas a partir de ceniza volcánica de La Palma (Tajogaite 2021)(Macla, 2023) Martínez del Pozo, Iker; López De Andrés, María Sol; García Lorenzo, María De La LuzEl evento eruptivo de 2021 (Tajogaite) en la isla de La Palma generó el depósito de más de 45 millones de m3 de ceniza volcánica, (Carracedo et al., 2022). Gran parte de este material se acumuló en zonas urbanas, material catalogado como un residuo municipal de limpieza variada por el Catálogo Europeo de Residuos y con destino a un vertedero. Su utilización para poner fin a la condición de residuo es una línea prioritaria para la UE (Directiva 2008/98/EC del Consejo y Parlamento Europeo) e incentiva la economía circular y diferentes Objetivos de Desarrollo Sostenible de la Agenda 2030 de la ONU. Por ello, en este trabajo se han transformado las cenizas volcánicas en zeolitas a partir de una síntesis hidrotermal con fusión previa, material con valor añadido por sus propiedades fisicoquímicas como son la interconexión de poros, intercambio iónico, capacidad de adsorción, catálisis, etc., y por sus diferentes aplicaciones en el sector de la industria química, petrolífera, en la agricultura y medio ambiente (Belviso et al., 2021).Item In situ use of mining substrates for wetland construction: results of a pilot experiment(Plants, 2024) Hernández Pérez, Carmen; Martínez López, Salvadora; Martínez Sánchez, Maria José; Martínez Martínez, Lucía Belén; García Lorenzo, María De La Luz; Pérez Sirvent, CarmenThis paper evaluates an experimental wetland as part of a pilot soil reclamation project in a mining area. The wetland was constructed using materials of mining origin from the area; most reactive materials of acid pH were stabilised using limestone filler. The study selected macrophytes that are tolerant to potentially toxic elements (PTEs) and resistant to salinity, namely Phragmites australis, Juncus effusus, and Iris pseudacorus. These macrophytes were then placed in pots containing substrates composed of different mixtures of topsoil, peat, and mining waste (black or yellow sand). A thorough analysis of the physicochemical and mineralogical characteristics of the materials included studies of PTE mobilisation. This study emphasises the significance of the rhizosphere in directing the transfer of PTEs to the plant and the correlation between the substrate and the development of plant defence mechanisms, such as the formation of Fe-plates. Scanning electron microscopy was used to highlight these aspects and validate the results of the analytical determinations. These wetlands can be proposed as a phytoremediation strategy for areas affected by mining and maritime influence. They are easy to construct and remain stable, providing important ecosystem services such as the natural attenuation of acid mine drainage, support for vegetation development and fauna, and a clean ecosystem.Item An evaluation of the environmental sensitivity to land degradation in Murcia Region, SE Spain(Fresenius Environmental Bulletin, 2015) Martínez-Sánchez, María José; Pérez-Sirvent, Carmen; García Lorenzo, María De La Luz; Molina, JoseAn assessment of the sensitivity to land degradation was carried out in the Murcia Region (SE Spain) by means of a modelling approach developed by the European Commission funded MEDALUS project (Mediterranean Desertification and Land Use). These areas are identified according to ESA index (Environmental Sensitive Areas index) that incorporates data on environmental quality (climate, vegetation, soil) together with management data. The obtained results were integrated into a Geographic Information System (GIS), and maps of environmental sensitivity to degradation were created. The proposed methodology allows to identify different degrees of vulnerability to land degradation, and also to analyse specific factors affecting desertification. Results showed that the study area is mostly located in the critical desertification class. Based on the results, almost all the land is included in high-critical class (C3), showing that the whole region is at high desertification riskItem Use of marble cutting sludges to immobilize heavy metals and decrease toxicity of contaminated soils.(Fresenius environmental bulletin, 2008) Martínez Sánchez, Maria José; García Lorenzo, María De La Luz; Pérez Sirvent, Carmen; Marimón, JorgeHeavy metal contamination of soils is particularly dangerous to living organisms. Several studies have demonstrated that marble cutting sludges show a high capacity to remove heavy metal from contaminated soils. In this study, the immobilization effect of these sludges used as an amendment was studied in two sediments from a site affected by mining activities and two soil samples from a highly industrialised area. The samples were mixed with marble cutting sludges to provide four stabilised samples from which forty lixiviums were studied. The results suggest that the addition of these sludges, consisting mainly of carbonates, to heavy metal-polluted soils and sediments, decreases available metal forms. As a complement to chemical analysis and the determination of total contaminants, bioassays can provide information on the stabilisation effects. The leached solutions showed a non-toxic effect when they were submitted to the Microtox® bioassay. The carbonate content seems to play a role in the chemical stabilisation of metals and in lowering the toxicity of these types of sample.