2 resultados para 1629
em Universidad Politécnica de Madrid
Resumo:
La relación entre fútbol y medios de comunicación exhibe señales claras de interdependencia. La presente investigación se planteó determinar el tratamiento que los principales medios impresos españoles dieron a la información durante la cobertura de cuatro derbis Barça-Madrid en abril y mayo de 2011. Se realizó un análisis de contenido de los diarios El País, Marca, Sport y La Vanguardia, estudiando la caracterización del mensaje elaborado por cada uno de ellos y las influencias que sobre el discurso periodístico tienen factores extradeportivos, principalmente económicos y sociopolíticos. El estudio muestra los cambios que está experimentando la prensa escrita para cubrir un fenómeno de impacto global.
Resumo:
Background and aims The high metal bioavailability and the poor conditions of mine soils yield a low plant biomass, limiting the application of phytoremediation techniques. A greenhouse experiment was performed to evaluate the effects of organic amendments on metal stabilization and the potential of Brassica juncea L. for phytostabilization in mine soils. Methods Plants were grown in pots filled with soils collected from two mine sites located in Central Spain mixed with 0, 30 and 60 tha?1 of pine bark compost and horse- and sheep-manure compost. Plant biomass and metal concentrations in roots and shoots were measured. Metal bioavailability was assessed using a rhizosphere-based method (rhizo), which consists of a mixture of low-molecular-weight organic acids to simulate root exudates. Results Manure reduced metal concentrations in shoots (10?50 % reduction of Cu and 40?80 % of Zn in comparison with non-amended soils), bioconcentration factor (10?50 % of Cu and 40?80 % of Zn) and metal bioavailability in soil (40?50 % of Cu and 10?30 % of Zn) due to the high pH and the contribution of organic matter. Manure improved soil fertility and was also able to increase plant biomass (5?20 times in shoots and 3?30 times in roots), which resulted in a greater amount of metals removed from soil and accumulated in roots (increase of 2?7 times of Cu and Zn). Plants grown in pine bark treatments and in non-amended soils showed a limited biomass and high metal concentrations in shoots. Conclusions The addition of manure could be effective for the stabilization of metals and for enhancing the phytostabilization ability of B. juncea in mine soils. In this study, this species resulted to be a potential candidate for phytostabilization in combination with manure, differing from previous results, in which B. juncea had been recognized as a phytoextraction plant.