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The aim of this work was to investigate the possibility of using several bush and arboreal plant species, usually present as ornamental plants in street and parks, as environmental indicators of pollution. This is a research paper that evaluates the real possibility of using a fast and low-cost procedure to evaluate the pollution degree through data obtained from plant species growing within an urban environment.Leaves of six different bush and arboreal species were collected from different parts of Madrid (Spain), ranging from highly polluted considered areas to medium and low contaminated ones. A total of 66 chemical elements, from major to minor and trace, were determined for every leaf sample by inductively coupled plasma-mass spectrometry. Statistical analyses were carried out using mainly box and whisker plots, linear discriminant analysis and cluster analysis.The pollution by different elements of the studied areas of Madrid cannot be considered generally dangerous for human health. The level detected for the contaminants, in general, is similar or lower than other urban cities. Pb and V concentrations in plant samples tend to increase as traffic density increases. The different studied plant species showed a different capability of accumulation of certain elements. Cedrus deodara accumulates specially Ag, Hg, Mo and V; Cupressus sempervirens, Zr; Pinus pinea, As and Sb; Nerium oleander Ni, Pb, Mo and Se; Ligustrum ovalifolium, Sc and V; and Pittosporum tobira, Ag, Cd, Rb and Sc.The leaves and needles collected from bush and arboreal plants common in this city have demonstrated to be useful to evaluate the level of pollution not only through the chemical analysis but also through the recognition of the visual injury symptoms. The application of multivariate statistical techniques combined with determining of element concentration and correlation analysis has been proved to be an effective tool for reach the objectives of the present work. This allows visualising quickly the damages and leading the sampling through the points of high-level pollution, saving analysis, time and money.

A gnamma or weathering pit is a small-sized cavity sculpted into solid rock which refills with rainwater. This study describes the main hydrological processes in gnammas and the underlying chemical interactions with the environment. Four gnammas developed in a granite tor from central Spain were chosen for monitoring and studying the dynamics of the gnamma–water system. Parameters monitored were air and water temperature, pH, ORP (redox potential), and conductivity. These measurements describe the system dynamics, without the need for special sampling or other potential interferences under low water volumes. Additionally, chemical analyses were carried out to contrast the chemical properties with the chemical composition. As a consequence of water volumes less than 100 L, daily fluctuations tended to cause the largest amplitude changes. Photosynthesis and respiration/putrefaction processes in the gnamma are responsible for daily pH fluctuations up to 4 units, with pH values often greater than 9. ORP generally alternates from positive to negative values as the solution oscillates diurnally between basic and acidic conditions. Conductivity values ∼ 10 μS/cm occur most of the year, with only minor daily oscillations. During dry periods, conductivity increases significantly with maximum values > 400 μS/cm. These high conductivity values reflect atmospheric inputs by summer rainstorms after prolonged dry periods. Therefore, conductivity does not relate directly with chemical species dissolved from the host rock. Silica was the main weathering product of granite dissolution during the year, with highest concentrations (> 200 ppm) in the rainy season. Low Si values measured during the dry season are in accordance with observed precipitation of amorphous silica within the gnamma. Seasonal variations in concentration are also present in Al and Fe as a response to ORP variations and evaporative dynamics, causing mineral dissolution and new mineral precipitation during the year. Relations among the measured parameters are influenced by several factors, including biological processes, temperature effects and water level variations. Factors such as large pH oscillations, basic pH values, acids from biological activity, and alkali cations all increase silicate solubility, thus favoring granite dissolution. Overflow of water during the winter, when the water is chemically enriched, is an effective mechanism to remove weathering products.

Despues de realizar analisis de laboratorio sobre un fragmento de vidrio descubierto en la alcazaba de Badajoz y de compararlo con otros ejemplos procedentes de Fustat, se demuestra la procedencia egipcia de aquel. Ademas, su comparacion con los analisis que tambien se llevaron a cabo sobre una botella "fatimi", conservada en el Museo de la Catedral de Astorga, ha permitido precisar que esta esta realizada en cristal de roca y que es un prototipo del fragmento aparecido en Badajoz. Todo ello anade un dato mas para reconocer, con el apoyo de argumentos arqueologicos, a El Cairo como seguro origen de la mayor parte de los cristales de roca llamados "fatimies" llegados hasta nosotros, que solo habian sido atribuidos a esa ciudad con ayuda de referencias literarias

We present here the first results of a study carried out in order to identify the roman lamps workshops in old Baetica, trying to fix the production of each one of them and their economical repercussions. Data concerning the local lamps production in late roman Corduba are shown. Together with the critical revision of archaeological materials published by other researchers, we also include several new lamps from recent field works in the modem city centre of this town (c/ Ambrosio de Morales-Munda). Analytical works have been performed with 22 clay samples of lamps coming from this excavation, determining their mineralogical and physico-chemical composition. Presentamos aquí los primeros resultados de un estudio sobre el reconocimiento, caracterización de la producción y repercusiones económicas de los talleres béticos de lucernas. Ponemos sobre la mesa todos aquellos datos que nos permiten hoy por hoy pensar en una producción local de lucernas en la Corduba tardorromana. Junto a la revisión de materiales arqueológicos ya conocidos, incluimos algunas lucernas inéditas procedentes de la excavación de urgencia desarrollada en uno de los solares del actual casco urbano de la ciudad (c/ Ambrosio de Morales-Munda). Hemos procedido además al análisis de la composición mineralógica y química de un conjunto de 22 muestras de pasta cerámica de lucernas procedentes de esta intervención arqueológica, con el objeto de comenzar a generar una Base de Datos que nos permita en un futuro cercano contrastar estos resultados con otros datos procesados analíticamente.