Effects of nitrogen supply on wheat and on soil nitrate

Field experiments were conducted at two locations during two growing seasons in the Ebro Valley (Spain), to evaluate the effects of N fertilization on yield and quality of Mediterranean-type wheat in irrigated conditions. Seven N treatments and a control were investigated. The average grain yields ranged from 2117 to 5551 kg ha-1 depending on the year and location. Grain protein ranged from 14.25 to 16.9%, and other quality parameters such as the dough strength (W) also varied with year and location, confirming the suitability of Mediterranean-type wheat and the climate for the production of good bread-making quality wheat. However, grain yields are normally low and both yields and quality can be greatly affected by the variability of this type of climate, even under irrigation. Under these conditions, grain yield increases were mainly due to an increase in the number of grains per m2 without a reduction in the N content per spike, suggesting that N in the grain was not source-limited, possibly due to the lower grain yields and relatively high soil nitrate concentrations. In soils with lower initial soil NO-3N contents, better grain yields could be achieved by applying a N fertilizer rate of about 100 kg N ha-1, whereas in soils with high initial NO-3N contents, no N or a maximum rate of 50 kg N ha-1 is needed to obtain a good grain quality, showing the possibility of producing high-quality wheat with a low amount of N fertilizer and thus increasing the sustainability of the cropping system.

Preface: Extreme events induced by weather and climate change: evaluation, forecasting and proactive planning

This special issue of Natural Hazards and Earth System Sciences (NHESS) contains eight papers presented as oral or poster contributions in the Natural Hazards NH-1.2 session on"Extreme events induced by weather and climate change: evaluation, forecasting and proactive planning", held at the European Geosciences Union (EGU) General Assembly in Vienna, Austria, on 13-18 April 2008. The aim of the session was to provide an international forum for presenting new results and for discussing innovative ideas and concepts on extreme hydro-meteorological events, including: (i) the assessment of the risk posed by the extreme events, (ii) the expected changes in the frequency and intensity of the events driven by a changing climate and by multiple human- induced causes, (iii) new modelling approaches and original forecasting methods to predict extreme events and their consequences, and (iv) strategies for hazard mitigation and risk reduction, and for a improved adaptation to extreme hydro-meteorological events ...

When supply travels far beyond demand: Causes of oversupply in Spain’s transport infrastructure

Spain’s transport infrastructure policy has become a paradigmatic case of oversupply and of mismatch with demand. The massive expansion of the country’s transport infrastructure over the last decade has not been a response to demand bottlenecks or previously identified needs. For this reason, the intensity of use today on all interurban modes of transport in Spain falls well below that of other EU countries. This paper analyzes the institutional and regulatory factors that have permitted this policy, allowing us to draw lessons from the Spanish case that should help other countries avoid the pitfalls and shortcomings of Spanish policy.

When supply travels far beyond demand: Causes of oversupply in Spain’s transport infrastructure

Spain’s transport infrastructure policy has become a paradigmatic case of oversupply and of mismatch with demand. The massive expansion of the country’s transport infrastructure over the last decade has not been a response to demand bottlenecks or previously identified needs. For this reason, the intensity of use today on all interurban modes of transport in Spain falls well below that of other EU countries. This paper analyzes the institutional and regulatory factors that have permitted this policy, allowing us to draw lessons from the Spanish case that should help other countries avoid the pitfalls and shortcomings of Spanish policy.

When supply travels far beyond demand: Institutional and regulatory causes of oversupply in Spain’s transport infrastructure

Spain’s transport infrastructure policy has become a paradigmatic case of oversupply and of mismatch with demand. The massive expansion of the country’s transport infrastructure over the last decade has not been a response to demand bottlenecks or previously identified needs. For this reason, the intensity of use today on all interurban modes of transport in Spain falls well below that of other EU countries. This paper analyzes the institutional and regulatory factors that have permitted this policy, allowing us to draw lessons from the Spanish case that should help other countries avoid the pitfalls and shortcomings of Spanish policy. Based on our analysis, we also discuss policy remedies and suggest reforms in different regulatory areas, which could help improve the performance of Spain’s infrastructure policy.

Cultural Planning and community sustainability: The case of the Cultural Facilities Plan of Catalonia (PECCAT 2010-20)

The government of Catalonia has developed a planning framework that seeks to establish the provision of cultural facilities throughout the country. The Cultural Facilities Plan of Catalonia (PECCAT) is based on an analysis of historical gaps and establishes a minimum spatial scheme. The plan responds to problems associated with the absence of a former similar instrument, which has led to an inconsistent and inappropriate cultural infrastructure that fails to fulfill its fundamental mission of securing the cultural rights of the population. The paper sets forth the aims of this policy and describes the objectives and basic characteristics of the plan and the expected outcomes. With the plan, the government of Catalonia seeks to rebalance the infrastructure within the territory and to ensure universal access to basic cultural services, while avoiding a logic of standardization and taking local communities into account. With the development of local plans in the municipalities, local governments encourage community participation processes to adapt and decide on priorities for action based on needs assessments and cultural opportunities for local sustainable development. The local plans focus on local cultural strengths, take advantage of opportunities, and aim to realize the cultural dynamics of a place through establishing an infrastructure that can best respond to the needs and cultural demands of the local communities, taking into account economic, social, and environmental sustainability.

Aquaculture production in areas with high seasonal temperature variations: Development of planning tools

Postprint (published version)

Factors explaining urban transport systems in large European cities: A cross-sectional approach

The paper analyses the link between human capital and regional economic growth in the European Union. Using different indicat The importance of effective and efficient mobility in large cities is becoming essential for planners and citizens due to its impact in terms of social, economic and geographic development. The aim of this research is to determine factors explaining urban transport systems by estimating aggregate supply and demand equations for 45 large European cities. Supply and Demand equations are separately and jointly determined using OLS and SUR estimation models. On one hand, our findings suggest the importance of economic variables on the supply of public transport. On the other, we highlight the role of those factors influencing the generalized cost of transport as main drivers of demand for public transit. Additionally, regional variables are introduced to capture institutional heterogeneity in this service, and we find that regional patterns are powerful explanatory determinants of urban transportation systems in Europe.

A survey on coverage path planning for robotics

Coverage Path Planning (CPP) is the task of determining a path that passes over all points of an area or volume of interest while avoiding obstacles. This task is integral to many robotic applications, such as vacuum cleaning robots, painter robots, autonomous underwater vehicles creating image mosaics, demining robots, lawn mowers, automated harvesters, window cleaners and inspection of complex structures, just to name a few. A considerable body of research has addressed the CPP problem. However, no updated surveys on CPP reflecting recent advances in the field have been presented in the past ten years. In this paper, we present a review of the most successful CPP methods, focusing on the achievements made in the past decade. Furthermore, we discuss reported field applications of the described CPP methods. This work aims to become a starting point for researchers who are initiating their endeavors in CPP. Likewise, this work aims to present a comprehensive review of the recent breakthroughs in the field, providing links to the most interesting and successful works

The influence of substratum type and nutrient supply on biofilm organic matter utilization in streams

We investigated the effect of benthic substratum type (sand and rocks) and nutrient supply (N and P) on biofilm structure and heterotrophic metabolism in a field experiment in a forested Mediterranean stream (Fuirosos). Rock and sand colonization and biofilm formation was intensively studied for 44 d at two stream reaches: control and experimental (continuous addition of phosphate, ammonia, and nitrate). Structural (C, N, and polysaccharide content and bacterial and chlorophyll density) and metabolic biofilm parameters (b-glucosidase, peptidase, and phosphatase enzyme activities) were analyzed throughout the colonization process. The epilithic biofilm (grown on rocks) had a higher peptidase activity at the impacted reach, together with a higher algal and bacterial biomass. The positive relationship between the peptidase activity per cell and the N content of the epilithic biofilm suggested that heterotrophic utilization of proteinaceous compounds from within the biofilm was occurring. In contrast, nutrient addition caused the epipsammic biofilm (grown on sand) to exhibit lower b-glucosidase and phosphatase activities, without a significant increase in bacterial and algal biomass. The differential response to nutrient addition was related to different structural characteristics within each biofilm. The epipsammic biofilm had a constant and high C:N ratio (22.7) throughout the colonization. The epilithic biofilm had a higher C:N ratio at the beginning of the colonization (43.2) and evolved toward a more complex structure (high polysaccharide content and low C:N ratio) during later stages. The epipsammic biofilm was a site for the accumulation and degradation of organic matter: polysaccharides and organic phosphorus compounds had higher degradation activities

Plan de seguridad y salud para el suministro y montaje del Parque Eólico Rancho Viejo en el T.M. de Medina-Sidonia (Cádiz)

No hace más de 3 años se podía leer en las revistas especializadas que España había pasado a ocupar el tercer puesto en el ranking mundial por potencia eólica instalada. La industria eólica española a su vez ha pasado a ocupar el tercer puesto en la fabricación e instalación de aerogeneradores, con una cuota de mercado del 13%, siendo así un sector con gran capacidad de exportación. Por otra parte, tras diez años de promulgación de la Ley 31/95, de 8 de noviembre, de Prevención de Riesgos Laborales, y después su desarrollo reglamentario, es un hecho incontestable que, pese a todo, y a los ingentes esfuerzos realizados por los distintos actores implicados en la prevención de riesgos laborales (Estado, Comunidades Autónomas, Agentes Sociales, Entidades especializadas, etcetera), existe un sector como el de la construcción que, constituyendo uno de los ejes del crecimiento económico de nuestro país, está sometido a unos riesgos especiales y continúa registrando una siniestralidad laboral muy notoria por sus cifras y gravedad. La legislación de prevención, los manuales sobre las distintas disciplinas preventivas, los libros especializados, los expertos... han abordado ya, con mayor o menor acierto, muchas de las cuestiones generales y específicas que afectan a la seguridad y salud: la evaluación de riesgos, las medidas higiénicas, los equipos de trabajo y equipos de protección individual, la planificación, la formación, los servicios de prevención , los sistemas de gestión de la prevención, las auditorías ... forman parte de los contenidos que se han ido creando en torno a este tema. No obstante, resulta de gran interés la elaboración de un estudio de Seguridad y Salud, en el que partiendo de un desarrollo técnico concreto, pero sobre todo integral, es decir, que comprenda todas las fases para el suministrp e instalación de aerogeneradores para un parque eólico, vayamos desgranando cada uno de los puntos desarrollados en su construcción. Entre las conclusiones más destacadas de este trabajo, se encuentra la definición de las condiciones relativas a la prevención de accidentes y enfermedades laborales durante la ejecución de los trabajos de suministro e instalación de un parque eólico y la gestión de su prevención, las características de las instalaciones preceptivas para higiene y bienestar de los trabajadores, así como directrices básicas mínimas, que deben reflejarse y desarrollarse en el Plan de Seguridad y Salud que las empresas contratistas deberán presentar para su aprobación por el director de obra, antes del comienzo de los trabajos, de forma que sea posible la disminución de accidentes laborales así como evitar las posibles sanciones administrativas y/o penales.

Sistemes logístics de codificació i identificació, i perspectives de futur

Comptar amb sistemes sofisticats de gestió o programes ERP (Enterprise Resource Planning) no és suficient per a les organitzacions. Per a què aquests recursos donin resultats adequats i actualitzats, la informació d’entrada ha de llegir-se de forma automàtica, per aconseguir estalviar en recursos, eliminació d’errors i assegurar el compliment de la qualitat. Per aquest motiu és important comptar amb eines i serveis d’identificació automàtica i col•lecció de dades. Els principals objectius a assolir (a partir de la introducció al lector de la importància dels sistemes logístics d’identificació en un entorn global d’alta competitivitat), són conèixer i comprendre el funcionament de les tres principals tecnologies existents al mercat (codis de barres lineals, codis de barres bidimensionals i sistemes RFID), veure en quin estat d’implantació es troba cadascuna i les seves principals aplicacions. Un cop realitzat aquest primer estudi es pretén comparar les tres tecnologies per o poder obtenir perspectives de futur en l’àmbit de l’autoidentificació. A partir de la situació actual i de les necessitats de les empreses, juntament amb el meravellós món que sembla obrir la tecnologia RFID (Radio Frequency Identification), la principal conclusió a la que s’arribarà és que malgrat les limitacions tècniques dels codis de barres lineals, aquests es troben completament integrats a tota la cadena logística gràcies a l’estandarització i la utilització d’un llenguatge comú, sota el nom de simbologies GTIN (Global Trade Item Number), durant tota la cadena de subministres que garanteixen total traçabilitat dels productes gràcies en part a la gestió de les bases de dades i del flux d’informació. La tecnologia RFUD amb l’EPC (Electronic Product Code) supera aquestes limitacions, convertint-se en el màxim candidat per a substituir els limitats codis de barres. Tot i això, RFID, amb l’EPC, no serà un adequat identificador logístic fins que es superin importants barreres, com són la falta d’estandarització i l’elevat cost d’implantació.