Estimation of the Radon Risk Under Different European Climates and Soil Textures

Radon is a radioactive gas produced from the natural radioactive decay of uranium and is found in almost all rocks and soils. In confined places (e.g., dwellings, workplaces, caves, and underground mines), radon may accumulate and become a substantial health risk since it is considered the second most important cause of lung cancer in many developed countries. Radon risk assessment commonly considers either field or estimate values of the radon concentration and the gas permeability of soils. However, radon risk assessment from single measurement surveys to radon potential largescale mapping is strongly sensitive to the soil texture variability and climate changes, and particularly, to the soil water content dynamic and its effect on soil gas permeability. In this paper, the gas permeability of soils, and thus, the estimation of radon risk, is studied considering the effect of three different climates following the Köppen classification and four soil textures on soil water content dynamics. This investigation considers the CLIGEN weather simulator to elaborate 100-year length climatic series; Rosseta 3 pedotransfer function to calculate soil hydraulics parameters, and the HYDRUS-1D software to model the dynamics of water content in the soil. Results reveal that climate strongly affects gas permeability of soils and they must be considered as an additional factor during the evaluation of radon exposure risk. The impact of climate and texture defines the soil water content dynamic. Coarse soils show smaller gas permeability variations and then radon risk, in this case, is less affected by the climate type. However, in clay soils, the effect of climate and the differences in soil water content derive in gas permeability variations between 100 and 1,000 times through an annual cycle. As a result, it may cross the boundary between two radon risk categories. Results deeply confirm that both climate and texture should be compulsory considered when calculating the radon exposure risk and in the definition of new strategies for the elaboration of more reliable geogenic radon potential largescale maps.This work was supported by the Spanish Ministry of Science, Innovation, and Universities [grant number RTI2018-099052-BI00] and Regional Governments of Comunidad Valenciana (Spain) [grant number AICO/2020/175]. A pre-doctoral research fellowship (PRE2019-088294) was awarded to SG-O for the project RTI2018-099052-BI00

El laboratorio de matemáticas como estrategia docente

En esta experiencia docente se pone en práctica una forma diferente de llevar a cabo las clases prácticas de algunas asignaturas de matemáticas de primer curso de la Facultad de Ciencias de la Universidad de Alicante. El objetivo es sustituir las habituales clases prácticas, donde el profesor realiza los ejercicios en la pizarra, por la resolución de problemas por parte de los alumnos incorporando además otras estrategias docentes; es decir, además de las hojas de ejercicios que el profesor prepara para los alumnos, los docentes preparan unas actividades prácticas para que sean realizadas en clase por los estudiantes, en grupos reducidos y guiados por el profesor. Estas actividades son puntuadas por el tutor y, tras ser devueltas a los alumnos, éstos deberán observar y analizar sus errores con la ayuda extra de las tutorías presenciales y virtuales. Con este método se consigue una mayor interacción entre alumno y profesor, un estudio continuo de la asignatura y una constante evaluación del profesor al alumno y del alumno a la asignatura

RadonPotential: An interactive web application for radon potential prediction under different climates and soil textures

The presence of radon in soil poses a significant health risk when it enters and concentrates indoors. The primary health problem associated with radon exposure is lung cancer, but it can also contribute to other respiratory issues. Estimating radon potential is a challenging task caused by the interaction of various environmental, geological, and variability factors. Although efforts are ongoing to improve radon potential assessment methodologies, there is a lack of software tools that estimate and model radon potential in different scenarios. The paper aims to develop a novel web-based software tool, RadonPotential, that predicts Geogenic Radon Potential by considering variations in climate and soil textures. The program runs using a constant radon concentration or estimates its concentration from the radium activity. RadonPotential calculates the transport of radon through a soil profile based on water content and soil texture. It also determines the dynamics of soil water content in different climates, incorporating long-term weather data under various climatic scenarios and local weather time series. The web-based format of the program increases its dissemination, usage, and manageability among a larger user base compared to an installable computer program. The program aims to provide a simplified and effective characterization of radon potential levels accessible to a wide range of scientists, technical experts and policymakers in developing strategies not only for radon measurement and mitigation buildings but also for developing more reliable large-scale radon potential maps.Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. This work has been partially supported by the Spanish Government (grant numbers RTI2018-099052-B-I00 and PID2021-123135OB-C21), and by the Conselleria de Innovación, Universidades, Ciencia y Sociedad Digital de la Generalitat Valenciana (project CIAICO/2022/038)

Laboratorio de Matemáticas

En este trabajo mostramos la forma planteada por los miembros de la red para llevar a cabo la evaluación continua de una asignatura de matemáticas impartida en los grados de Química y Geología de la Facultad de Ciencias de la Universidad de Alicante. La idea principal es cambiar las tradicionales clases prácticas de pizarra por parte del profesor por otras estrategias más participativas por parte del alumno. Así además de las clásicas hojas de problemas que el profesor prepara para la resolución por parte del alumno, éstas se combinan con unas prácticas se preparan por parte de los componentes de la red y que son realizadas en clase por parte de los alumnos trabajando en grupos reducidos. Tras su elaboración los profesores puntúan y devuelven dichas prácticas a los alumnos para que puedan notar y examinar sus errores. La idea es acercar e interactuar de manera constante entre el alumno y el profesor así como realizar una evaluación continua basada en una gran cantidad de información

Laboratorio de Matemáticas

En este trabajo mostramos la forma planteada por los miembros de la red para llevar a cabo la evaluación continua de una asignatura de matemáticas impartida en los grados de Química y Geología de la Facultad de Ciencias de la Universidad de Alicante. La idea principal es cambiar las tradicionales clases prácticas de pizarra por parte del profesor por otras estrategias más participativas por parte del alumno. Así además de las clásicas hojas de problemas que el profesor prepara para la resolución por parte del alumno, éstas se combinan con unas prácticas se preparan por parte de los componentes de la red y que son realizadas en clase por parte de los alumnos trabajando en grupos reducidos. Tras su elaboración los profesores puntúan y devuelven dichas prácticas a los alumnos para que puedan notar y examinar sus errores. La idea es acercar e interactuar de manera constante entre el alumno y el profesor así como realizar una evaluación continua basada en una gran cantidad de información

Study of Rull Cave dynamics to understand the complex relationships between soil, cave and external atmosphere

22–25 de junio de 2022, University of MalagaRull Cave is a karstic cavity located in Vall d’Ebo (Alicante), in the Southeast of Spain. The cave is developed in massive Miocene conglomerates and Cretaceous limestones. The cave presents a single rounded hall of 1535 m length with a 3 m2 entrance located in its highest part. It is a tourist cave with an average of 15550 visitors per year. A detailed microenvironmental monitoring system has been measuring the environmental conditions in the cave indoors and outdoors, as well as the physical properties above the cave, from 2012 to 2021 to understand the gaseous dynamics and their relationships in this three-component system (soil-cave-atmosphere). Besides the presence of visitors, Rull Cave presents, every year, stable values of temperature (average value of 16.2 ºC, with variations of ±1.0ᵒC) and relative humidity (97.5%). The microclimatic measurements of air cave reveal two different gaseous stages in an annual cycle. In the study period, maximum average values of CO₂ and ²²²Rn are reached in the hottest months (4000 ppm of CO₂ and 5600 Bq/m3, respectively), while coldest months are related to the lowest gaseous concentrations (480 ppm of CO₂ and 427 Bq/m3, respectively). The annual cycles described by CO₂ and ²²²Rn are consequence of the gaseous exchange between the outside atmosphere and the indoors cavity through the porous system and fissures of the soil and the host rock, controlled by the variations of the indoors and outdoors environmental variables. Average value of atmospheric temperature and relative humidity are, respectively, 16.1 ºC, nearly coincident with indoors temperature, and 69.9%, with an average measured annual precipitation of 437 mm. Soil dynamics is strongly related to cave dynamics. Thus, soil conditions are also measured. For the study period, average soil temperature and volumetric water content are 16.6 ºC and 0.2. Complementary discrete sampling of δ13C of CO₂ in cave, outdoor atmosphere and soil has been also used to characterize the spatial distribution and temporal variations of the gaseous concentration in background atmosphere, cave and soil air as well as the relationship between them. Results reveal that the dynamics of ²²²Rn and CO₂ in the cave air may show different patterns depending on the time-frequency conditions and they are defined by the complex relationships between external and internal factors. Findings allow lately to preserve the quality of the cave indoors and to understand the possible risk derived from the presence of indoors hazardous substances

Las rocas Metamórficas: una mirada a través del microscopio

La presente red docente I3CE tuvo por objetivo principal facilitar el aprendizaje de la Petrografía de rocas metamórficas mediante la generación de contenidos e imágenes relativos a los principales tipos de rocas metamórficas. El material generado se centró principalmente en los aspectos petrográficos (texturas, asociación mineral, clasificación y nomenclatura). Estos contenidos e imágenes se presentaron en una página web, donde se incluyen fotografías de láminas delgadas vistas al microscopio petrográfico, con sus respectivas descripciones. Las muestras trabajadas son las que existen en el laboratorio utilizadas dentro de la docencia de la asignatura Petrología Ígnea y Metamórfica (3er curso del Grado en Geología de la Universidad de Alicante). El recurso objeto de trabajo en esta red es el Atlas Digital de Petrografía de Rocas Metamórficas, que es continuación de las rocas Volcánicas (PIM) trabajadas por nuestro grupo el curso anterior, y va dirigido a promover la autonomía durante el estudio del alumnado a través del uso de ambientes virtuales, así como facilitar material que le permita a los estudiantes profundizar en su formación. Se ha realizado una evaluación de la acción/experiencia, a través de la percepción por parte de estudiantes y docentes, de la implementación del citado recurso, de modo que ha permitido valorar la calidad y facilidad de manejo de esta herramienta, así como posibles mejoras de la estructuración de la página web

Air Quality Monitoring for Preventive Conservation of the Built Heritage Deteriorated by Salt Crystallization

The Santo Domingo Diocesan School (Orihuela, SE Spain) is a singular case study that relates air quality monitoring and stone conservation. The monument suffers severe damage due to salt crystallization by rising damp, which is related to the indoor environment dynamics, high groundwater salt content, and microstructure, the building’s porous stone (biocalcarenite). Results revealed that 222Rn concentration in indoor air is low due to the building’s high ventilation rate, despite the medium-low geogenic radon potential in the area. Wavelets analysis showed that ventilation is caused by outdoor and indoor temperature variations and directly affects the 222Rn and CO2 dynamics inside the church. CO2, as well as relative humidity (RH), presented periodicities with intermediate frequencies (5–8 days) related to visits. These RH and temperature (T) variations intensified the salt damage by increasing the frequency of dissolution-crystallization cycles. The mineralogical characterization and geochemical calculations concluded that chlorides (halite and sylvite), sulfates (thenardite, epsomite, hexahydrite and aphthitalite) and nitrates (niter) present from dissolution forms to whiskers and hopper-type morphologies. This indicates high saturation values and, therefore, higher crystallization pressure values within the porous media of the biocalcarenite. On the contrary, the near-equilibrium crystal shape and incongruent precipitation reaction for humberstonite suggest a lower alteration for this salt on the building stone.This work was supported by the Spanish Ministry of Science, Innovation, and Universities [grant number RTI2018-099052-BI00], and Regional Governments of Comunidad Valenciana (Spain) [grant number AICO/2020/175] and Madrid (Spain) [Top Heritage, grant number S2018/NMT-4372]. A pre-doctoral research fellowship (PRE2019-088294) was awarded to S.G.O. for the project RTI2018-099052-BI00. A pre-doctoral research fellowship (GRISOLIAP/2020/124) was awarded to M.C.R. by the Department of Innovation, Universities, Science and Digital Society of the Generalitat Valenciana.Peer reviewe

Curso MOOC: Introducción a la modelización geoquímica con PHREEQC

El trabajo realizado en esta red-I3CE se ha se ha centrado en la adaptación, implementación y evaluación de docencia online para modelización geoquímica con el código PHREEQC, con el objeto de realizar un curso MOOC a través de la plataforma Moodle de la Universidad de Alicante. Las actividades llevadas a cabo han ido encaminadas en la investigación en docencia en geoquímica, en el desarrollo de material específico orientado a facilitar el autoaprendizaje y la autoevaluación del alumnado en entorno Moodle-UA. La motivación de esta red-I3CE surge por la importancia y complejidad de la modelización geoquímica, principalmente en geoquímica acuosa y ambiental. Durante el presente curso, el material del obtenido se utilizó en las prácticas de la asignatura Geoquímica y Prospección geoquímica (tercer curso del Grado de Geología). Se desarrollaron actividades tanto sincrónicas como asincrónicas, donde el alumnado adquirió los conocimientos de la modelización geoquímica en un entorno Moodle. Las metodologías y los recursos de aprendizaje llevados a cabo se han valorado a través de encuestas a los estudiantes, los cuales han tenido una aceptación excelente por parte del alumnado. Las actividades realizadas han tenido una aceptación muy positiva, aunque el alumnado prefiere de forma manifiesta el formato sincrónico y presencial en aulas de informática

222Rn and CO2 monitoring in soil and indoor atmosphere to understand changes in the gaseous dynamics of Rull cave (Spain)

Rull cave is a karstic cave located in Vall d’Ebo (Alicante, Southeast of Spain) developed in massive Miocene conglomerates and Cretaceous limestones. Processes in soil above Rull cave and outdoor atmosphere directly influence the underground environment of the cave. Continuous and discrete monitoring of cave atmosphere and soil (from 2012 to 2022) allows to characterise the spatial distribution and temporal variations of the gaseous concentration (222Rn and CO2) and understand the relationship between the processes which occurred in the 3-component system (soil-cave-atmosphere). Besides the presence of visitors, Rull cave maintains stable values of mean temperature (16.2 °C) and relative humidity (97.6%). In an annual cycle the cave presents two different gaseous stages (stagnation and ventilation). Maximum average values of CO2 and 222Rn concentration are reached within the stagnation stage, in the warmest period of the year. On the contrary, in the ventilation stage (in the coldest months) the cave reaches the lowest concentrations in its inner atmosphere. For the study period, daily average CO2 and 222Rn concentrations are 2008 ppm and 1745 Bq/m3, respectively. Results show that the dynamics of 222Rn and CO2 in the cave air follow different patterns defined by the complex relationships between external and internal factors. Findings from this study provide substantial information about the environmental situation of the cave atmosphere in terms of air quality for visitors and workers.Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. This work was supported by the Spanish Ministry of Science, Innovation and Universities (project RTI2018-099052-BI00), and Regional Government of Comunidad Valenciana (Spain) (project AICO/2020/175), and with collaboration of the project PID2019-110603RB-I00. A pre-doctoral research fellowship (PRE2019-088294) was awarded to S.G.O. (linked to the project RTI2018-099052-BI00). A pre-doctoral research fellowship (GRI-SOLIAP/2020/124) was awarded to M.C.R. by the Department of Innovation, Universities, Science and Digital Society of the Generalitat Valenciana, and a pre-doctoral research fellowship (FPU20/05157) was awarded to N.G.M. by the Spanish Ministry of Science, Innovation and Universities