Application of biochar for the restoration of metal(loid)s contaminated soils

Biochar has recently aroused great interest for the restoration of contaminated soils since it improves soil properties and induces the immobilization of pollutants. This study evaluates the use of biochar from plant pruning, applied as an amendment, for immobilizing metal(loid)s in a highly contaminated soil as well as for reducing the phytotoxicity of these pollutants by promoting natural revegetation. For this purpose, a bioassay with Trifolium pratense L. was used to test the effectiveness of the soil amendment in greenhouse conditions. Three treatments were carried out including soil contaminated with metal(loid)s (RA), and this soil was amended with biochar at different dosage: 4% (RA4B) and 8% (RA8B). A non-contaminated soil (NC) from a nearby area not affected by contamination was used as a control. The results show that biochar increased soil pH by several units depending on the dose used, 8% being the most effective one. Biochar treatments also reduced soluble and bioavailable forms of Zn and Cu. Likewise, phytotoxicity was significantly reduced, promoting seed germination and biomass with plant growth values similar to the nonpolluted soil. In light of the results obtained, the evaluation of the bioremediation potential of biochar under field conditions can be considere

Effect of parent material and atmospheric deposition on the potential pollution of urban soils close to mining areas

A. Vázquez-Arias was awarded a grant by the Spanish Ministry of Science, Innovation and Universities within the Programa de Formación de Profesorado Universitario (FPU19/01989). Dr. A. Parviainen's fellowship ‘Juan de la Cierva –Incorporación’ (IJCI-2016-27412) was funded by the Spanish Ministry of Science, Innovation and Universities. The research performed at the UGR was also supported by the Research Project RTI 2018-094327-B-I00 (Ministry of Science, Innovation and Universities). Fellowships, research, and infrastructure grants supporting this research performed at the Instituto Andaluz de Ciencias de la Tierra (UGR-CSIC) have been (co)funded by the European Regional Development Fund (ERFD) and the European Social Fund (ESF) of the European CommissionThe aim of this study is to analyse the concentration and determine the sources of potentially toxic elements (PTEs) in urban soils under the influence of mining activities. To this end, topsoil samples were collected in the public parks and green areas in Minas de Riotinto (a town next to one of the largest open pit mines in the world) and Aracena (a nearby town outside the area of influence of the mine). After determining the concentrations of elements of interest single bondCr, Co, Ni, Cu, Zn, As, and Pb— the values were compared in terms of the soil location and origin (in-situ or ex-situ), and with the background and regulatory levels for the region. The elemental concentrations in the fine fraction of the soils (particles <50 μm) were also measured. The concentrations of some PTEs (Cu, As and Pb), also found in the dust from nearby mines, were higher in the in-situ soils of Minas de Riotinto than in those of Aracena. The concentrations of PTEs in ex-situ soils of both towns were much lower than in in-situ soils, and similar between the two locations, revealing the influence of the parent material as a primary source of PTEs. However, the concentrations of As and Cu in the ex-situ soils of Minas de Riotinto were significantly higher than in those of Aracena, while a significant increase of these elements in the fine fraction was seen for both in-situ and ex-situ soils. These two elements are directly related to mining activity, implying that atmospheric deposition of dust from the mines contributes to the greater concentration of PTEs in the soils of Minas de Riotinto. Because these sources lead to soils with potentially dangerous concentrations of pollutants, they should be further studied in relation to their long-term influence on human healthS

Application of Biochar for the Restoration of Metal(loid)s Contaminated Soils

Funding: The work has been supported by funds from the Spanish Ministry of Economy, Industry and Competitiveness through the Project “CTM2017-86504-R”, and by Ministry of Science, Innovation and Universitiesam trought Research Project “RTI2018-094327-B-I00”.Biochar has recently aroused great interest for the restoration of contaminated soils since it improves soil properties and induces the immobilization of pollutants. This study evaluates the use of biochar from plant pruning, applied as an amendment, for immobilizing metal(loid)s in a highly contaminated soil as well as for reducing the phytotoxicity of these pollutants by promoting natural revegetation. For this purpose, a bioassay with Trifolium pratense L. was used to test the effectiveness of the soil amendment in greenhouse conditions. Three treatments were carried out including soil contaminated with metal(loid)s (RA), and this soil was amended with biochar at different dosage: 4% (RA4B) and 8% (RA8B). A non-contaminated soil (NC) from a nearby area not affected by contamination was used as a control. The results show that biochar increased soil pH by several units depending on the dose used, 8% being the most effective one. Biochar treatments also reduced soluble and bioavailable forms of Zn and Cu. Likewise, phytotoxicity was significantly reduced, promoting seed germination and biomass with plant growth values similar to the non-polluted soil. In light of the results obtained, the evaluation of the bioremediation potential of biochar under field conditions can be considered.Ministry of Science, Innovation and Universitiesam trought Research Project RTI2018-094327-B-I00Ministerio de Economía, Industria y Competitividad, Gobierno de España CTM2017-86504-

Validation of a new portable metabolic system during an incremental running test

We tested a new portable metabolic system, the Jaeger Oxycon Mobile (OM) at a range of running speeds. Six subjects carried out, in random order, two incremental tests on a treadmill, one of them using the OM, and the other using the Jaeger Oxycon Pro (OP). There are systematic errors in the measurements of oxygen consumption (VO2) and respiratory exchange ratio (RER) with the OM. Production of CO2 (VCO2) tends to be overestimated by the OM, although the differences are not significant. Ventilation (VE) showed very similar values in both analyzers. Data of VO2 and RER were corrected with a regression equation which minimised the differences among the devices. The portable metabolic system OM makes systematic errors in measurements of VO2 and RER which can be adjusted with a regression analysis to obtain data comparable to those obtained by fixed system

Technosols Derived from Mining, Urban, and Agro-Industrial Waste for the Remediation of Metal(loid)-Polluted Soils: A Microcosm Assay

This research was funded by the project RTI2018-094327-B-I00 (Spanish Ministry of Science and Innovation). A.A.-G. thanks the Spanish Ministry of Science and Innovation for their predoc- toral fellowship granted under application references FPU-18/02901; M.P.-L. thanks the Research Project RTI2018-094327-B-I00 (Spanish Ministry of Science and Innovation) for his contract; and A.R-F. thanks the Junta de Andalusia Post-doctoral Operating Research Program FEDER 2014-2020 (ref. E-RNM-444-UGR20) for her contract.Supplementary Materials: The following supporting information can be downloaded at https://www.mdpi.com/article/10.3390/toxics11100854/s1This study evaluated the effectiveness of six Technosols designed for the remediation of polluted soils (PS) by metal(loid)s at physicochemical, biological, and ecotoxicological levels and at a microcosm scale. Technosols T1–T6 were prepared by combining PS with a mix of organic and inorganic wastes from mining, urban, and agro-industrial activities. After two months of surface application of Technosols on polluted soils, we analysed the soil properties, metal(loid) concentration in total, soluble and bioavailable fractions, soil enzymatic activities, and the growth responses of Trifolium campestre and Lactuca sativa in both the Technosols and the underlying polluted soils. All Technosols improved the unfavourable conditions of polluted soils by neutralising acidity, increasing the OC, reducing the mobility of most metal(loid)s, and stimulating both the soil enzymatic activities and growths of T. campestre and L. sativa. The origin of organic waste used in the Technosols strongly conditioned the changes induced in the polluted soils; in this sense, the Technosols composed of pruning and gardening vermicompost (T3 and T6) showed greater reductions in toxicity and plant growth than the other Technosols composed with different organic wastes. Thus, these Technosols constitute a potential solution for the remediation of persistent polluted soils that should be applied in large-scale and long-term interventions to reinforce their feasibility as a cost-effective ecotechnology.Spanish Ministry of Science and Innovation RTI2018-094327-B-I00, FPU-18/02901Junta de Andalusia FEDER 2014-2020 E-RNM-444-UGR2

ZnMn2O4 as a material for supercapacitors and its stability against the electrolyte

The electrolyte is an essential part of a supercapacitor, conditioning its performance. Thus, the specific capacitance measured for the supercapacitor electrode in the typical three-electrode arrangement of an electrochemical cell is sometimes not reflected in the supercapacitor. For this reason, ZnMn2O4 electrodes have been manufactured by spray pyrolysis on ITO/glass. The electrodes have been characterized electrochemically, and in symmetrical supercapacitors in which three types of electrolyte have been used, studying the effect of the electrolyte on the stability of the electrode and the capacity of the supercapacitorUniversidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Effect of population density on size of edible snail helix aspersa müller

An assessment was made of the effects of population density on Helix aspersa Müller snails at their nursery stage. A sample of 3420 animals was used, grouped at eighteen density levels: from 600 to 11100 snails/m2. The results demonstrate that higher population density decreased growth (p<0.001). Furthermore the optimum snail population density at the nursery stage ranged from 600 to 4300 snails/m2.Se estudia el efecto de la densidad sobre el tamaño del Helix aspersa Müller durante la primera fase de crecimiento. Se utilizan 18 niveles de densidad entre 600 a 11100 animales/m2. Los resultados indican la existencia de diferencias significativas en el crecimiento según el nivel de densidad (p<0,001), de modo que a medida que se incrementa la densidad disminuye el tamaño. La densidad óptima, en primera edad, oscila entre 600 y 4300 animales/m2

Study of heavy metal and arsenic concentrations in olive farm soils, sierra mágina, jaen, spain.

The content of heavy metals and arsenic was studied in 35 soils under olive cultivation in the Sierra Mágina, Jaen, Spain. The concentrations of chromium (Cr), nickel (Ni), copper (Cu), lead (Pb), zinc (Zn) and arsenic (As) were determined at depths between 0 - 20 and 20- 40 cm. These soils developed on carbonate materials, predominantly Petric Calcisols and Calcaric Regosols (FAO, 1999). The homogeneity of parental material was responsible for the lack of significant variation seen in soil properties, and alsoheavy metal and arsenic content at the depths studied. Copper was the only element that varied over depth (pEn Sierra Mágina, Jaén (España) fueron seleccionados 35 suelos dedicados al cultivo del olivar en los que se estudió la concentración de cromo (Cr), níquel (Ni), cobre (Cu), plomo (Pb), Zinc (Zn) y arsénico (As) a profundidades entre 0 - 20 y 20 - 40 cm. Estos suelos se desarrollan sobre materiales carbonatados, predominando Calcisoles pétricos y Regosoles calcáricos (FAO, 1999). La homogeneidad del material parental es responsable de la ausencia de variaciones significativas en las propiedades de los suelos a las profundidades estudiadas, así como en el contenido de metales pesados y arsénico. El Cu es el único elemento que varía con la profundidad (p and lt; 0.01), presentando un valor promedio más elevado entre 0 y 20 cm debido a la aplicación de controles fitosanitarios en los cultivos de la región. En los suelos con texturas arcillosa y limosa se presentan concentraciones más altas de Cr y Ni, mientras que el resto de metales analizados y el As no presentan variaciones significativas con las principales propiedades físicas y químicas de los suelos. Los elementos estudiados no exceden el nivel de referencia establecido para suelos por la Junta de Andalucía y presentan concentraciones similares a las encontradas en rocas equivalentes y en suelos no contaminados. Los valores promedio en As, Cr, Cu, Ni, Pb y Zn están relacionados con las concentraciones heredadas del material litológico del que se derivan

Adsorción de metales pesados en Andisoles, Vertisoles y ácidos húmicos

La presente investigación estudió la adsorción de cinco metales pesados (Cd, Cu, Ni, Pb y Zn) en tres adsorbentes, dos suelos agrícolas colombianos (Typic Melanudand y Epiaquert ústico arcilloso fino isohipertérmico 1%) y ácidos húmicos (AH) extraídos de leonardita, de España, mediante la metodología descrita por Mosquera et al. (2007). A los suelos y a los AH se les determinaron propiedades químicas como pH, Capacidad de Intercambio Catiónico (CIC), carbono orgánico (%CO), bases intercambiables y contenido total de metales. La composición química de los AH se determinó empleando técnicas espectrométricas como ICP_MS, FTIR, UV-Vis, CPMAS 13C NMR y Py-GC/MS-THMA. Los resultados de la adsorción de metales se ajustaron al modelo de Freundlich, y muestran un comportamiento disímil de los absorbentes en relación a los metales estudiados, es así como la máxima capacidad de adsorción (K) y la fuerza de retención (n) de los metales es significativamente diferente (pPbCuNiZn, Andisol: PbCuCdZnNi, y Vertisol: CdPbCuNiZn; y para n, Ácidos Húmicos: PbZnCdCuNi, Andisol: CuNiZnPbCd, y Vertisol: ZnNiCuPbCd.This research studied the adsorption of five heavy metals (Cd, Cu, Ni, Pb and Zn) in three adsorbents, two Colombian agricultural soils (Typic Melanudand and fine clay 1% isohyperthermic-Ustic Epiaquert) and humic acids (HA) extracted from leonardite, of Spain. In both, HA and soils, the chemical properties determined were: pH, cation exchange capacity (CEC), organic carbon (% OC), exchangeable bases and total content of metals. The hemical composition of HA was determined using spectrometric techniques as ICP_MS, FTIR, UV-Vis, and CPMAS 13C NMR and Py-GC/MS-THMA. The results from the adsorption of metals in the three adsorbents were adjusted to Freundlich model, and these show a different behavior of the absorbers relative to the metals studied, in the same way the maximum adsorption capacity (K) and the retention force (n) of metals is significantly different (p 0.05). According to K and n of each adsorbent, the adsorption selectivity sequences of the metals has the following order of preference for K: In Humic Acids: Cd Pb Cu Ni Zn, Andisol: Pb Cu Cd Zn Ni, and Vertisol: Cd Pb Cu Ni Zn. For n, Humic Acids: Pb Zn Cd Cu Ni, Andisol: Cu Ni Zn Pb Cd, and Vertisol: Zn Ni Cu Pb C

Estrategias docentes para la adaptación de la docencia en Ciencias Jurídicas al entorno on line y semipresencial

The health situation caused by COVID-19 has forced Spanish universities to adopt tools and measures aimed at adapting e-learning education. The teaching of legal subjects was initially at a disadvantage, as it usually made use of traditional methodologies. To solve this problem, a group of lecturers from the UA and the UMH have designed and implemented a series of strategies and methodologies in order to adapt teaching to the virtual environment in a satisfactory manner. The present work gathers and exposes the experiences deployed during the academic year 2020/2021 in certain subjects in the legal field. The analysis of these experiences shows that the current catalogue of technological tools and methodologies makes it possible to achieve the aforementioned objective of adapting to the virtual environment. However, there are a series of factors beyond the control of the teaching staff and which require the commitment of the rest of the members of the university community.La situación sanitaria provocada por la COVID-19 ha forzado a las universidades españolas a adoptar herramientas y medidas orientadas a una adaptación de la enseñanza e-learning. La docencia en materias jurídicas partía de una situación inicial de desventaja al hacer uso habitualmente de metodologías de carácter tradicional. Para solventar este problema, un grupo de profesoras y profesores de la UA y la UMH ha diseñado e implementado una serie de estrategias y metodologías docentes con el fin de adaptar la enseñanza al entorno virtual de manera satisfactoria. El presente trabajo recoge y expone las experiencias docentes desplegadas durante el curso académico 2020/2021 en determinadas asignaturas del ámbito jurídico. Del análisis de estas experiencias se deriva que el catálogo actual de herramientas tecnológicas y metodologías docentes permite alcanzar el citado objetivo de adaptación al entorno virtual. No obstante, existen una serie de factores que escapan al control del profesorado y que requieren el compromiso del resto de miembros de la comunidad universitaria