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Circular economy is based on the re-use of wastes. However, it also implies the application of solutions that can help to reduce the environmental and climate change impacts. On the one hand, the preparation of materials for construction from mining activities generates wastes, for instance in marble and stone industry. On the other hand, the use of these materials in construction also generates wastes, construction and demolition wastes (CDW), which account for more than a third of all waste generated in the EU. In the case of the SE of Spain, stone preparation (cutting, polishing, etc…) produces fine and coarse wastes, mainly from carbonate rocks and secondary from granites. The large building activity produces residues in a wide variety of materials (concrete, bricks, wood, glass, metals and plastics). Mining restoration could be an opportunity to reuse those materials, as many mining holes are abandoned and need to be refilled before the preparation of a soil cover and landscape recovery.In this work, it has been studied the restoration of an ancient mining hole (up to 10 meters depth and 21000 m2), situated in the SE of Spain under a BSk climate -Köppen and Geiger classification-, with marble wastes and CDW, and finally the formation of a Technosol (IUSS Working Group WRB) which can support a vegetation cover. Several actions were done as follow: refilling of the mining hole first with marble wastes (calcareous materials mainly of different sizes), the second was the addition of CDW and the third was the mixing of CDW with topsoil (approximately last 50 cm depth of surface restoration) forming the surface and conditioning the topography to reduce soil erosion. This action was accompanied by the construction of a central drainage stone filled canal (50 cm depth). After two years, Pinus halepensis vegetation was introduced (261 pine trees). Two years later, soil samples were taken (0-5 cm to measure bulk density and 0-20 cm depth to measure pH, electrical conductivity and organic matter) in eight selected points distributed equidistant in the restored area. The results showed that the soil had a slightly basic pH, but not homogeneous along the surface (from 8.13 to 8.89). In the case of the electrical conductivity, the variation between samples was greater (0.49 to 2.41 dS/m) and probably controlled by the lithology of the area, in the north close to Triassic formations with soluble gypsum formations and in the middle to the south to calcareous rocks. The organic matter (between 1.13 to 1.59 %) and the bulk density (1.40 to 1.47 g/cm3) were more homogeneous in the restored area. The survival of the pine trees was successful and more than 80%, considering no irrigation applied excepting the first month.The use of this materials could be of interest to reduce the impact, favoured the circular economy and restoration of ancient mining areas, recovering the landscape and the soil functions.

Salinity is one of the major problems affecting soils of arid and semi-arid environments. This research, carried out around a Mediterranean wetland area, aimed to assess the spatial distribution of soil properties (salinity, texture fractions, pH, organic matter and % of carbonates) by using soil laboratory and geostatistical analysis to determine an adequate strategy for soil remediation. Ordinary kriging was applied to map soil properties and field observations were used to define land use classes. Better map accuracy was obtained for these soil properties: electrical conductivity (EC) (RMSE = 0.529 dS m -1 ), clay (RMSE = 9.1%), silt (RMSE = 7.28%) and sand (RMSE = 10.69%). The results suggested an opposite relation between silt and sand and a clear distribution of electrical conductivity of soils. Moreover, comparing with the observed land use classes, plants cultivated around the wetland seem to be distributed due to their tolerance to soil salinity. Permanent crops were restricted to less salinized soil, whereas arable crops were close to saline zones and uncultivated areas appear in the most salinized areas. Cropping systems can be used as an effective strategy for salinity control and phytoremediation.

This research study analysed the effect of adding fine—fMRA (0.25% and 50%)—and coarse—cMRA (0%, 25% and 50%)—mixed recycled aggregate both individually and simultaneously in the development of sustainable recycled concretes that require a lower consumption of natural resources. For this purpose, we first conducted a physical and mechanical characterisation of the new recycled raw materials and then analysed the effect of its addition on fresh and hardened new concretes. The results highlight that the addition of fMRA and/or cMRA does not cause a loss of workability in the new concrete but does increase the amount of entrained air. Regarding compressive strength, we observed that fMRA and/or cMRA cause a maximum increase of +12.4% compared with conventional concrete. Tensile strength increases with the addition of fMRA (between 8.7% and 5.5%) and decreases with the use of either cMRA or fMRA + cMRA (between 4.6% and 7%). The addition of fMRA mitigates the adverse effect that using cMRA has on tensile strength. Regarding watertightness, all designed concretes have a structure that is impermeable to water. Lastly, the results show the feasibility of using these concretes to design elements with a characteristic strength of 25 MPa and that the optimal percentage of fMRA replacement is 25%.

Nowadays lacks in environmental education were detected even living in times of global change. In this research, the acquisition of knowledge related to environmental consciousness in secondary school students in northeast Spain is examined. A questionnaire for each secondary course was made with different kind of questions: specific of the course and of the previous knowledge. After a statistical analysis, with R programming language, a unilateral hypothesis contrast where the mean responses of the students answered correctly at the beginning and the end of the different courses of secondary education, were contrasted. After analysis, the results shows that the mean responses answered correctly at the end of the course is greater than the mean at the beginning of course in most cases studied, except two groups. The findings of this study indicate that the education of our students conclude with a meaningful learning as indicated but we should not neglect the non-formal education received by students in order to have people environmentally conscious.RESUMENActualmente se han detectado carencias en la educación ambiental aun estando viviendo momentos de cambio global. En el presente estudio de investigación, se examina la adquisición de los conocimientos relacionados con la concienciación ecológica en los alumnos de educación secundaria en el nordeste de España. Se realizó un cuestionario para cada curso con diferentes tipos de preguntas: específicas de curso y conocimientos previos. Tras un análisis estadístico, con el lenguaje y entorno de programación para análisis estadístico R, se realizó un contraste de medias unilateral donde se contrastó la media de respuestas respondidas correctamente de los alumnos de los diferentes cursos de educación secundaria, a final y a inicio de curso, de dicho cuestionario. Tras el análisis de los resultados se observa que la media de respuestas respondidas correctamente a final de curso es mayor que la media al inicio de curso en la mayoría de casos estudiados a excepción de dos grupos. Las conclusiones de este estudio indican que la educación que reciben nuestros alumnos concluye en un aprendizaje significativo tal y como se indica aunque no debemos descuidar la formación no formal que reciben los alumnos para así tener ciudadanos concienciados con el medio ambiente. Contacto principal: meritxell.notari@alu.umh.es

Ecological concepts are not a recent matter, international organizations have already increased their efforts to provide better environmental education and ecological consciousness, although despite these efforts, a lack of attitudes and concepts were detected in the northeast of Spain. We evaluated the acquisition of concepts related to environmental education in the students as proposed by current legislation, as well as their relation to different parameters, such as geographical location, type of school, and gender. The result suggests that the students achieve a meaningful learning of the concepts proposed by legislation and that acquisition of this knowledge is related to gender and geographical location, but not to the type of secondary school.

Since the early sixties, national and international organizations have increased their efforts to provide better environmental education and ecological consciousness, although despite these efforts, a lack of attitudes and concepts was detected among students from secondary education of Spain. This lack of attitudes among students may be due to deficient concepts passed on from their teachers. Within this framework, the objective of this study is to evaluate the ecological consciousness level possessed by the teachers. The results of this study show that over 97% of the teachers possess enough knowledge on ecological consciousness concepts related to the syllabus from secondary education. It is essential to facilitate the evolution of society and its future generations, those on which the future and the development of nature and the world depend.

This article analysed the presence of trace metals (essential elements and pollutants) and soil properties in rural abandoned soils of a Mediterranean region. The soil properties determined were texture, pH, equivalent calcium carbonate, soil organic matter, availability of micronutrients (Fe, Mn, Cu, and Zn), and acid microwave digestion extraction to measure the trace metals considered as main pollutants (Cu, Zn, Cd, Cr, Ni, and Pb). Descriptive statistics and correlations were used to determine the relations among these parameters. pH, soil organic carbon (SOC), and clay were the main properties that controlled the availability of essential metals. pH was the main factor related to these metals in these calcareous soils. However, SOC, which can be incremented by adding organic fertilizers for soil rehabilitation as a sustainable practice, played an important role. Mean values of the metal composition in soils (Cu, Zn, Cd, Cr, Ni, and Pb) obtained in this study were similar to values reported for other areas in the Mediterranean basin.