19 research outputs found
Luz blanca en la normativa española como mejora de la sostenibilidad
En la actualidad, en nuestro país debido al índice de reproducción cromática en las lámparas del alumbrado exterior, el color que suelen presentar es un color amarillento, lo cual puede tener graves consecuencias en la seguridad de los ciudadanos al distorsionar algunos aspectos de la realidad. Es por este motivo que pretendemos resaltar las bondades que presenta la luz blanca, como la mejora de la eficiencia energética o en el comportamiento de los usuarios a la hora de aprovechar los espacios públicos en horarios nocturnos. Para asegurarnos que la introducción de la Luz Blanca en la normativa no presenta inconvenientes, esta investigación se presenta dividida en tres campos diferentes: Crimen, Seguridad Vial y Eficiencia Energética, con el propósito de evaluar el mayor número de factores que afectan al alumbrado exterior
Eficiencia energética del alumbrado exterior en España
El alumbrado público en España representa entre un 40% y 60 % del total del consumo eléctrico de las ciudades, lo que supone unos gastos de electricidad y mantenimiento en torno a los 1.200 millones de euros al año. Sin embargo, los avances realizados en esta materia pueden ayudar a reducir este consumo energético hasta en un 45%. Si echamos un vistazo al resto de los países de la Unión Europea, podemos comprobar como España es el país que presenta un mayor consumo energético en alumbrado exterior por habitante, llegando a duplicar el valor de países como Alemania o Reino Unido. Por este motivo pretendemos realizar un pequeño análisis sobre el estado de nuestras instalaciones, para lo cual realizaremos una comparación con uno de los países más eficientes de la Unión Europea, el Reino Unido. Esta comparación nos ayudará a analizar algunos de los aspectos que consideramos que han sido pasados por alto en la normativa de eficiencia energética de alumbrado exterior de España, los cuales podrían suponer un aumento en la eficiencia de nuestros sistemas de alumbrado, con el correspondiente ahorro energético que esto podría conllevar
Functional traits determine plant co-occurrence more than environment or evolutionary relatedness in global drylands
Plant–plant interactions are driven by environmental conditions, evolutionary relationships (ER) and the functional traits of the plants involved. However, studies addressing the relative importance of these drivers are rare, but crucial to improve our predictions of the effects of plant–plant interactions on plant communities and of how they respond to differing environmental conditions. To analyze the relative importance of – and interrelationships among – these factors as drivers of plant–plant interactions, we analyzed perennial plant co-occurrence at 106 dryland plant communities established across rainfall gradients in nine countries. We used structural equation modelling to disentangle the relationships between environmental conditions (aridity and soil fertility), functional traits extracted from the literature, and ER, and to assess their relative importance as drivers of the 929 pairwise plant–plant co-occurrence levels measured. Functional traits, specifically facilitated plants’ height and nurse growth form, were of primary importance, and modulated the effect of the environment and ER on plant–plant interactions. Environmental conditions and ER were important mainly for those interactions involving woody and graminoid nurses, respectively. The relative importance of different plant–plant interaction drivers (ER, functional traits, and the environment) varied depending on the region considered, illustrating the difficulty of predicting the outcome of plant–plant interactions at broader spatial scales. In our global-scale study on drylands, plant–plant interactions were more strongly related to functional traits of the species involved than to the environmental variables considered. Thus, moving to a trait-based facilitation/competition approach help to predict that: (1) positive plant–plant interactions are more likely to occur for taller facilitated species in drylands, and (2) plant–plant interactions within woody-dominated ecosystems might be more sensitive to changing environmental conditions than those within grasslands. By providing insights on which species are likely to better perform beneath a given neighbour, our results will also help to succeed in restoration practices involving the use of nurse plants
Decoupling of soil nutrient cycles as a function of aridity in global drylands
18 páginas.- 10 figuras.- 72 referencias.- Online Content Any additional Methods, Extended Data display items and Source Data are available in the online version of the paper; references unique to these
sections appear only in the online paper..- Puede conseguir el texto completo en el Portal de la producción científica de la Universidad Complutense de Madrid https://produccioncientifica.ucm.es/documentos/5ec78dc52999520a1d557660 .- o en lel respositorio institucional CONICET digital https://ri.conicet.gov.ar/bitstream/handle/11336/29204/CONICET_Digital_Nro.ead4e2ed-0da6-4041-814b-259e8f27bbf6_D.pdf?sequence=5&isAllowed=yThe biogeochemical cycles of carbon (C), nitrogen (N) and phosphorus (P) are interlinked by primary production, respiration and decomposition in terrestrial ecosystems1. It has been suggested that the C, N and P cycles could become uncoupled under rapid climate change because of the different degrees of control exerted on the supply of these elements by biological and geochemical processes1,2,3,4,5. Climatic controls on biogeochemical cycles are particularly relevant in arid, semi-arid and dry sub-humid ecosystems (drylands) because their biological activity is mainly driven by water availability6,7,8. The increase in aridity predicted for the twenty-first century in many drylands worldwide9,10,11 may therefore threaten the balance between these cycles, differentially affecting the availability of essential nutrients12,13,14. Here we evaluate how aridity affects the balance between C, N and P in soils collected from 224 dryland sites from all continents except Antarctica. We find a negative effect of aridity on the concentration of soil organic C and total N, but a positive effect on the concentration of inorganic P. Aridity is negatively related to plant cover, which may favour the dominance of physical processes such as rock weathering, a major source of P to ecosystems, over biological processes that provide more C and N, such as litter decomposition12,13,14. Our findings suggest that any predicted increase in aridity with climate change will probably reduce the concentrations of N and C in global drylands, but increase that of P. These changes would uncouple the C, N and P cycles in drylands and could negatively affect the provision of key services provided by these ecosystems.This research is supported by the European Research Council (ERC) under the European Community's Seventh Framework Programme (FP7/2007-2013)/ERC Grant agreement no. 242658 (BIOCOM), and by the Ministry of Science and Innovation of the Spanish Government, grant no. CGL2010-21381. CYTED funded networking activities (EPES, Acción 407AC0323). M.D.-B. was supported by a PhD fellowship from the Pablo de Olavide University.Peer reviewe
The Gaia mission
Gaia is a cornerstone mission in the science programme of the EuropeanSpace Agency (ESA). The spacecraft construction was approved in 2006, following a study in which the original interferometric concept was changed to a direct-imaging approach. Both the spacecraft and the payload were built by European industry. The involvement of the scientific community focusses on data processing for which the international Gaia Data Processing and Analysis Consortium (DPAC) was selected in 2007. Gaia was launched on 19 December 2013 and arrived at its operating point, the second Lagrange point of the Sun-Earth-Moon system, a few weeks later. The commissioning of the spacecraft and payload was completed on 19 July 2014. The nominal five-year mission started with four weeks of special, ecliptic-pole scanning and subsequently transferred into full-sky scanning mode. We recall the scientific goals of Gaia and give a description of the as-built spacecraft that is currently (mid-2016) being operated to achieve these goals. We pay special attention to the payload module, the performance of which is closely related to the scientific performance of the mission. We provide a summary of the commissioning activities and findings, followed by a description of the routine operational mode. We summarise scientific performance estimates on the basis of in-orbit operations. Several intermediate Gaia data releases are planned and the data can be retrieved from the Gaia Archive, which is available through the Gaia home page. http://www.cosmos.esa.int/gai
Continuous chlorophyll fluorescence, gas exchange and microclimate monitoring in a natural soil crust habitat in Tabernas badlands, Almería, Spain: progressing towards a model to understand productivity
The Soil Crust International project aims to better understand the functioning of biological soil crust environments (BSC) in Europe in order to understand the importance of these ecosystems. The final objective of this project is to inform and strengthen protection strategies for these types of habitats in the frame of the European Union. To achieve this, four different soil crust regions have been chosen in Europe following latitudinal and altitudinal gradients. The work presented here is based on the simultaneous monitoring of gas exchange, chlorophyll fluorescence and microclimate of the most abundant BSC in one of these four locations, the Tabernas badlands, Almeria, SE Spain, one of the driest regions in Europe. The five BSC types monitored are dominated by the lichen species Squamarina cartilaginea, Diploschistes diacapsis, Toninia albilabra and Psora decipiens and by the moss Didymodon rigidulus. We aim to understand the conditions in which the BSC are metabolically active in order to get a better knowledge about the contribution of the BSC to the carbon budget of the ecosystem. Our first results after nearly 1 year of chlorophyll fluorescence and microclimatic monitoring linked to gas exchange data during typical activity days obtained in the field suggest similar physiological performance between the different BSC types studied. BSC were active under suboptimal conditions, and activity duration was not different whether measured by chlorophyll a fluorescence or CO2 gas exchange, a relationship that will be the basis of a productivity model