Definición de un Modelo Edafogeomorfológico para la Identificación de Necesidades de Manejo y Recuperación de Suelos a Nivel Local. Caso Cuenca Cañada La Gorda, Machiques Colón, Estado Zulia, Venezuela.

El objetivo de este trabajo es generar un modelo Edafogeomorfológico útil en la identificación de necesidades de manejo de suelos, se realizó un estudio en el área de la cuenca Cañada La Gorda Machiques-Colón, estado Zulia, Venezuela, caracterizada por un clima tropical de condición subhúmeda, con duración del periodo de crecimiento (DPC) de 230 días, régimen de humedad Ustic y de temperatura Isohipertémico. Se empleó el enfoque de la ecuación factorial de formación de suelos para el análisis y descripción biofísica de los factores a lo largo de una carena. El relieve caracterizado a partir de fotografías aéreas, imágenes de satélites y de chequeos sistemático mediante transectos en el sentido del flujo del escurrimiento; la vegetación a través del uso de la tierra, la cobertura vegetal, la identificación de las especies dominantes a partir de sus nombres vernáculos y la definición de indicadores de vegetales (Iv). Los suelos fueron descritos y clasificados según la Taxonomía de suelos y valorados mediante el modelo paramétricode Riquier et al. (1970) para determinar el índice de productividad (Ip). Se caracterizaron dos paisajes gemorfológicos: Colinar (C) y Valle (V), seis posiciones geomorfológicas entre ambos paisajes definidas por la sucesión de relieves en el sentido de la pendiente: Tope de colina-loma (TC), mesa conservada (MC), vertientes de mesa alta (VA), media (VM), baja (VB) y valle intracolinar (VI); e igual número de perfiles de suelos representativos, los cuales mostraron edafogénesis muy avanzada con Ip inferiores a 8% en todas las posiciones, exceptuando la VB, con una productividad de 13%. El uso de la tierra es a base de pastoreo semi-intensivo de plantas forrajeras introducidas. Las formaciones vegetales predominante fueron los matorrales y arbustales dispersos, acompañados con restos de una selva tropófila fuertemente afectada por la extracción forestal y la conversión en áreas de pastoreo. Se identificaron 8 Iv, asociados fuertemente con condiciones de físicas e hidrológicas del suelo. El alto impacto de las actividades humanas sobre el suelo y vegetación, expresado a través de los procesos de erosión activa, la ausencia de áreas boscosas y la baja productividad de los sistemas de ganadería reportada para la zona, señalan la necesidad de reorientación del uso actual de la tierra, para lo cual se plantean alternativas como la incorporación de bosques protectores y sistemas agrosilvopastoriles In order to generate an Edaphogeomorphological model to be used for the identification of management requirements of soils, a study was carried out in the area of the Cañada La Gorda watershed, Machiques Colon, Zulia State with a tropical climate, subsumid conditions with a growing period of 230 days, an Ustic soil moisture and Isohypertermic regimes. The soils factorial equation approach was used for the analisis and description of the factors of soil formation throughout a soil catena. Relief was characterized through aerial photographs, satellite images and systematic checks of transects drawn in the sense of surface runoff and also taking into account geomorphological features. Vegetation cover and land use were described and vegetation components were indified by its local names to defined vegetations indicators (VI) for the local conditions. Soils were described and classified according to soil taxonomy and valued by means of a parametric model proposed by Riquier et al, (1970) for determining the productivity index (PI). Two geomorphological landscapes were defined: Hilly and Valley with six positions within the landscapes: hilltop (round or elongated), preserved tableland summit, slopes of high, medium and low tableland and valleys between hills. Representative soils of each position were studied showing a highly advanced degree of edaphogenesis with PI values below 8% in all positions except the valleys with a PI of 13%. Land use type is based on semi intensive pasturing of introduced forage species, with a vegetation of brushwood and scattered shrubs, with some trees relicts of woods affected by timber extraction and turn to grassland Eight VI were identified, highly associated to local physical and hidrological soil conditions. The enormous impact of human activity on soils and vegetation as shown by active erosion processes and absence of wooded areas and the low productivity of livestock systems reported for the area, indicates the necessity of a reorientation of the present land use introducing alternatives like the incorporation of protective woods and agrosilvopastoral management systems.

Proposal of an Alternative Model for Speed-Flow Relationship in Two-Lane Highways

A research has been carried out in two-lanehighways in the Madrid Region to propose an alternativemodel for the speed-flowrelationship using regular loop data. The model is different in shape and, in some cases, slopes with respect to the contents of Highway Capacity Manual (HCM). A model is proposed for a mountainous area road, something for which the HCM does not provide explicitly a solution. The problem of a mountain road with high flows to access a popular recreational area is discussed, and some solutions are proposed. Up to 7 one-way sections of two-lanehighways have been selected, aiming at covering a significant number of different characteristics, to verify the proposed method the different classes of highways on which the Manual classifies them. In order to enunciate the model and to verify the basic variables of these types of roads a high number of data have been used. The counts were collected in the same way that the Madrid Region Highway Agency performs their counts. A total of 1.471 hours have been collected, in periods of 5 minutes. The models have been verified by means of specific statistical test (R2, T-Student, Durbin-Watson, ANOVA, etc.) and with the diagnostics of the contrast of assumptions (normality, linearity, homoscedasticity and independence). The model proposed for this type of highways with base conditions, can explain the different behaviors as traffic volumes increase, and follows a polynomial multiple regression model of order 3, S shaped. As secondary results of this research, the levels of service and the capacities of this road have been measured with the 2000 HCM methodology, and the results discussed. © 2011 Published by Elsevier Ltd.

Forest Hydrology, Soil Conservation and Green Barriers in Canary Islands

In volcanic islands, the rainfall regime and its torrential nature, together with the steep slopes and the soil types present are considered to be some of the main factors affecting forest hydrology and soil conservation. In such environments, rain regime is generally irregular and characterized by short and intense rainfalls, which could cause destructive flows at times, followed by long periods of rain absence. The volcanic nature of these islands have as a direct resultant steep slopes which influences the runoff volume and speed, as well as the amount of topsoil susceptible to be detached and transported downstream. The soil type also affects the susceptibility to erosion processes. Andisols are the most typical soil on volcanic islands. Their particularities derive their mineral constituents, called short-range-order products, which provide these soils with an increased structural stability, which in turn reduces their susceptibility to erosion. However, the land use changes and the environmental factors such as rain regime and steep slopes may be determinant factor in destabilizing these soils and ultimately a cause for soil erosion and runoffs, which become a threat to the population downstream. Green barriers have been traditionally used to prevent or reduce these processes, also to enhance the dew effect and the fog water collection, and as a firebreak which acts as a barrier to slow or stop the progress of a wildfire. Wooded species present and subsequently their performance have a major influence on their effectiveness. The use of this natural erosion and fire control methods on volcanic islands is discussed in this paper.

Significado empírico de la multifractalidad de la precipitación

El objetivo central de la presente investigación es profundizar la interpretación de los parámetros multifractales en el caso de las series de precipitación. Para ello se aborda, en primer lugar, la objetivación de la selección de la parte lineal de las curvas log-log que se encuentra en la base de los métodos de análisis fractal y multifractal; y, en segundo lugar, la generación de series artificiales de precipitación, con características similares a las reales, que permitan manipular los datos y evaluar la influencia de las modificaciones controladas de las series en los resultados de los parámetros multifractales derivados. En cuanto al problema de la selección de la parte lineal de las curvas log-log se desarrollaron dos métodos: a. Cambio de tendencia, que consiste en analizar el cambio de pendiente de las rectas ajustadas a dos subconjuntos consecutivos de los datos. b. Eliminación de casos, que analiza la mejora en el p-valor asociado al coeficiente de correlación al eliminar secuencialmente los puntos finales de la regresión. Los resultados obtenidos respecto a la regresión lineal establecen las siguientes conclusiones: - La metodología estadística de la regresión muestra la dificultad para encontrar el valor de la pendiente de tramos rectos de curvas en el procedimiento base del análisis fractal, indicando que la toma de decisión de los puntos a considerar redunda en diferencias significativas de las pendientes encontradas. - La utilización conjunta de los dos métodos propuestos ayuda a objetivar la toma de decisión sobre la parte lineal de las familias de curvas en el análisis fractal, pero su utilidad sigue dependiendo del número de datos de que se dispone y de las altas significaciones que se obtienen. En cuanto al significado empírico de los parámetros multifratales de la precipitación, se han generado 19 series de precipitación por medio de un simulador de datos diarios en cascada a partir de estimaciones anuales y mensuales, y en base a estadísticos reales de 4 estaciones meteorológicas españolas localizadas en un gradiente de NW a SE. Para todas las series generadas, se calculan los parámetros multifractales siguiendo la técnica de estimación de la DTM (Double Trace Moments - Momentos de Doble Traza) desarrollado por Lavalle et al. (1993) y se observan las modificaciones producidas. Los resultados obtenidos arrojaron las siguientes conclusiones: - La intermitencia, C1, aumenta al concentrar las precipitaciones en menos días, al hacerla más variable, o al incrementar su concentración en los días de máxima, mientras no se ve afectado por la modificación en la variabilidad del número de días de lluvia. - La multifractalidad, α, se ve incrementada con el número de días de lluvia y la variabilidad de la precipitación, tanto anual como mensual, así como también con la concentración de precipitación en el día de máxima. - La singularidad probable máxima, γs, se ve incrementada con la concentración de la lluvia en el día de precipitación máxima mensual y la variabilidad a nivel anual y mensual. - El grado no- conservativo, H, depende del número de los días de lluvia que aparezcan en la serie y secundariamente de la variabilidad general de la lluvia. - El índice de Hurst generalizado se halla muy ligado a la singularidad probable máxima. ABSTRACT The main objective of this research is to interpret the multifractal parameters in the case of precipitation series from an empirical approach. In order to do so the first proposed task was to objectify the selection of the linear part of the log-log curves that is a fundamental step of the fractal and multifractal analysis methods. A second task was to generate precipitation series, with real like features, which allow evaluating the influence of controlled series modifications on the values of the multifractal parameters estimated. Two methods are developed for selecting the linear part of the log-log curves in the fractal and multifractal analysis: A) Tendency change, which means analyzing the change in slope of the fitted lines to two consecutive subsets of data. B) Point elimination, which analyzes the improvement in the p- value associated to the coefficient of correlation when the final regression points are sequentially eliminated. The results indicate the following conclusions: - Statistical methodology of the regression shows the difficulty of finding the slope value of straight sections of curves in the base procedure of the fractal analysis, pointing that the decision on the points to be considered yield significant differences in slopes values. - The simultaneous use of the two proposed methods helps to objectify the decision about the lineal part of a family of curves in fractal analysis, but its usefulness are still depending on the number of data and the statistical significances obtained. Respect to the empiric meaning of the precipitation multifractal parameters, nineteen precipitation series were generated with a daily precipitation simulator derived from year and month estimations and considering statistics from actual data of four Spanish rain gauges located in a gradient from NW to SE. For all generated series the multifractal parameters were estimated following the technique DTM (Double Trace Moments) developed by Lavalle et al. (1993) and the variations produced considered. The results show the following conclusions: 1. The intermittency, C1, increases when precipitation is concentrating for fewer days, making it more variable, or when increasing its concentration on maximum monthly precipitation days, while it is not affected due to the modification in the variability in the number of days it rained. 2. Multifractility, α, increases with the number of rainy days and the variability of the precipitation, yearly as well as monthly, as well as with the concentration of precipitation on the maximum monthly precipitation day. 3. The maximum probable singularity, γs, increases with the concentration of rain on the day of the maximum monthly precipitation and the variability in yearly and monthly level. 4. The non-conservative degree, H’, depends on the number of rainy days that appear on the series and secondly on the general variability of the rain. 5. The general Hurst index is linked to the maximum probable singularity.

Conexión con la meseta desde el Ebro medio de las vías romanas como base de la malla territorial de España

No tenemos conocimiento de ninguna red de caminos prerromanos que sirvieran como base de una posible malla territorial de España. Sin embargo, una sociedad prerromana sin caminos, por muy fragmentada y aislada que fuera, es algo improbable y mucho menos en la Edad del Hierro. Por eso en época prerromana existían infinidad de caminos, muchos de los cuales hoy han desaparecido y otros han sobrevivido, casi siempre con sus recorridos mejorados. Los pueblos prerromanos aprovecharon vías naturales de comunicación (ríos, vados, valles, puertos naturales, llanuras, etc.) para tender sus caminos. En sus orígenes no siguieron pautas concretas, si no que los caminos se originaban por el tránsito (de personas, ganados, mercancías, etc.) de un lugar a otro. De este modo la red viaria prerromana era caótica y anárquica: todo camino tenía numerosos ramales y variantes, según las necesidades. Pendientes excesivas, anchuras variables, etc., en decir eran vías espontáneas, surgidas sin ninguna planificación aparente. Los recorridos en general eran cortos, aunque algunas investigaciones actuales están demostrando que algunas de las cañadas ganaderas más importantes, como la Galiana, y de largo recorrido, eran de origen prerromano. En el caso de la península Ibérica, y más concretamente en el caso de la Meseta, el territorio estaba fragmentado en diversos pueblos y tribus, agrupados según criterios étnicos y culturales y con contactos con los pueblos próximos que motivan la preponderancia de caminos de recorrido cortos. Solo la necesidad de llevar los rebaños (de cabras y ovejas sobre todo) desde las serranías en verano a las llanuras en invierno, motivaría viajes más largos en los que algunas cañadas ganaderas jugarían un papel más importante. Con la llegada de los romanaos, se implantó en Hispania una densa red viaria, cuya construcción se prolongó durante toda la dominación romana, siendo reparadas muchas calzadas y vías en varias ocasiones. En época romana la red caminera era variada y estaba constituida por “las calzadas” que comunicaban puntos importantes, eran muy transitadas, de ahí que la administración romana las mantuviera siempre en buen estado, para asegurar el intercambio comercial entre zonas distintas, cobro de impuestos, etc. “Los caminos de tierra (viae terrenae)” que además de las calzadas, que podemos asemejar a las actuales carreteras de primer y segundo orden, constituían la infinidad de caminos locales y comarcales. Los trazados se realizaron unos en época romana, y otros muchos apoyándose en los caminos de la época prerromana, éstas vías no se realizaban buscando el recorrido más corto entre dos puntos, ni tampoco el más cómodo y con un firme estructural de menor importancia que en las calzadas. Tampoco estaban hechos para un tipo concreto de transporte, por lo que nos encontraríamos algunos que por su anchura permitían el paso de carros, y otros que sólo permitirían el paso a pie, a caballo o en burro. Solían ser, como hemos indicado, caminos de tierra con acabados en zahorras y recorridos en su mayor parte cortos y medianos. Dentro de la malla territorial de España las calzadas constituirían las denominadas “viae publicae” que constituían la red principal y esqueleto vertebrador de Hispania. Los caminos de tierra constituirían los denominados “actus” caminos de carácter regional que configuraban la mayor parte de la red. Muchas de las “viae publicae” y de los “actus” tendrían su origen en las “viae militares” que habrían sido los primeros construidos, apoyándose en muchas ocasiones en los caminos prerromanos, por los romanos para realizar la conquista de Hispania y que luego con la Paz romana habrían tenido otro tipo de uso. Dentro de estas “viae militares” tuvieron una importancia relevancia aquellas que se utilizaron en la conquista de la Celtiberia, culminada con la caída de Numantia. Dentro de ellas tuvo una importancia fundamental la vía romana del río Alhama, objeto de esta Tesis, que facilitaría el desplazamiento de los ejércitos romanos desde Graccurris, primera ciudad romana fundada en el Ebro medio, hasta Numantia. Desde la época Augusta, la vía romana del río Alhama, pasaría a formar parte de los denominados “actus” formando parte de la malla territorial de la Península Ibérica como vía de comunicación entre la Meseta y el Ebro Medio. We do not have knowledge of any network of ways prerromanos that were serving as base of a possible territorial mesh of Spain. Nevertheless, a company prerromana without ways, for very fragmented and isolated that was, is something improbable and great less in the Age of the Iron. Because of it in epoch prerromana existed infinity of ways, many of which today have disappeared and others have survived, almost always with his improved tours. The people prerromanos took advantage of natural routes of communication (rivers, fords, valleys, natural ports, plains, etc.) to stretch his ways. In his origins concrete guidelines did not continue, if not that the ways were originating for the traffic (of persons, cattle, goods, etc.) to and from. Thus the network viaria prerromana was chaotic and anarchic: all way had numerous branches and variants, according to the needs. Excessive slopes, variable widths, etc., in saying were spontaneous routes arisen without no apparent planning. The tours in general were short, though some current investigations are demonstrating that some of the most important cattle glens, as the Galiana, and of crossed length, were of origin prerromano. In case of the Iberian Peninsula, and more concretely in case of the Plateau, the territory was fragmented in diverse peoples and tribes, grouped according to ethnic and cultural criteria and with contacts with the near peoples that motivate the prevalence of short ways of tour. Only the need to take the flocks (of goats and sheeps especially) from the mountainous countries in summer to the plains in winter, would motivate longer trips in which some cattle glens would play a more important paper. With the arrival of the romanos, a dense network was implanted in Roman Spain viaria, whose construction extended during the whole Roman domination, being repaired many causeways and routes in several occasions. In Roman epoch the pertaining to roads network was changed and constituted by " the causeways " that were communicating important points, they were very travelled, of there that the Roman administration was supporting always in good condition, to assure the commercial exchange between different zones, collection of taxes, etc. "The dirt tracks (viae terrenae)" that besides the causeways, which we can make alike to the current roads of the first and second order, were constituting the infinity of local and regional ways. The tracings were realized some in Roman epoch, and great others resting on the ways of the epoch prerromana, these routes were not realized looking for the most short tour neither between points, two nor neither most comfortable and with a structural road surface of minor importance that in the causeways. They were not also done for a concrete type of transport, for what some of us would think that for his width they were allowing the step of cars, and others that only would allow the step afoot, astride or in donkey. They were in the habit of being, since we have indicated, dirt tracks with ended in zahorras and tours in his most short and medium. Inside the territorial mesh of Spain the causeways would constitute the called ones "viae publicae" that constituted the principal network and skeleton vertebrador of Roman Spain. The dirt tracks would constitute the "actus” called ways of regional character that were forming most of the network. Many of "viae publicae" and of the "actus" they would have his origin in " viae military" that would have been the first ones constructed, resting on many occasions on the ways prerromanos, for the Romans to realize the conquest of Roman Spain and that then with the Roman Peace they would have had another type of use. Inside these "viae military" had an importance relevancy those that were in use in the conquest of the Celtiberia, reached with Numantia's fall. Inside them a fundamental importance had the Roman route of the river Alhama, object of this Thesis, which would facilitate the displacement of the Roman armies from Graccurris, the first Roman city been founded on the average Ebro, up to Numantia. From the August epoch, the Roman route of the river Alhama, would happen to form a part of the "actus” forming a part of the territorial mesh of the Iberian Peninsula as road link between the Plateau and the Average Ebro.

Simulation of oil productivity and quality of N-S oriented olive hedgerow orchards in response to structure and interception of radiation

Simulations of oil yield and quality are presented for N–S oriented, hedgerow olive orchards of a range of structures (viz. canopy depth, canopy width, canopy slope and row spacing) using responses of yield and quality parameters to solar irradiance on canopy walls measured in a range of orchards, cv. Arbequina, in Spain. Results reveal that orchard yield of hedgerows of rectangular shape reaches a maximum when canopy depth equals alley width (row spacing−canopy width) and decreases at wider spacing, and/or with wider canopies, as the length of productive row decreases per unit area. Maximum yields for 4-m deep canopies were 2885 kg ha−1 at 1-m width and 5-m row spacing, 2400 kg ha−1 at 2-m width and 6-m spacing, and 2050 kg ha−1 at 3-m width and 7-m spacing. Illumination of canopies can be increased by applying slopes to form rhomboidal hedgerows. Substantial yield advantage can be achieved, especially for wide hedgerows, partly by closer row spacing that increases row length per unit area. By comparison, responses to latitude in the range 30–40◦ are small and do not warrant different row spacing. Oil quality parameters also respond to orchard structure. Responses are presented for oleic and palmitic acid, stability, and maturity index. Oleic acid content declines as alley spacing increases and is smaller, shallow than in wide, deep canopies. Palmitic acid content, stability, and maturity index increase with row alley spacing and are greater in narrow, shallow than in wide, deep canopies.

Puente de ferrocarril sobre el Mittellandkanal en Braunschweig

The bridge over the Mittellandkanal is located in the municipality of Braunschweig, a city of Low Saxony located in Mid-North Germany, between Berlin and Hannover, 50 km away from this last city. The city of Braunschwig has 248.867 inhabitants (December 2010). The orography of the zone is practically even, with some slopes in the surrounding area, with a no important variation of the ground elevation, characterized by a big uniformity and a great visual quality. In this zone the canal flows from west to east, from the Dortmundkanal until the Elbe river, so it has a length of 325,3 km. The normal flora from the zone is farmland with some little forests not very big and not very important. But the Mittellandkanal lies at the North of Brauschweig, that means that in the zone of the canal there is a change between the urban area and the rural area. For this reason in the zone of the bridge we start to find farmlands and forest, however the constructions and buildings are still present in this area. The railway line that is going to be built will unite the North-center of Germany with the North-East of Germany because some of the following factors: •Overstress of the only existing line in the moment that connects Berlin with the North-East extreme of Germany. •No direct connection with the North-Easth Germany with other important German cities from South and West of Germany. •Replacement of the old existing one way line in the area that has to be renewed. •Modernization of the old railway lines of Germany. Schedule order by the European Union and the German Government. The actual lines of the zone do not have the necessary conditions and characteristics to satisfy the demand of the travelers that want to travel all over Germany with the railway avoiding using other transports like plan or car. For these reasons the necessity of the replacement of the old railway line and the aim to create a union with the North-East Germany that has a deficit of transport infrastructures and connections with the rest of the country and Europe. Although the new railway line provokes some disadvantages when constructing it is indispensable to build this railway line. The pass of the railway line through Braunschweig has not been random. The zone Braunschweig-Wolfsburg is a very industrialized area because of some companies like Wolkswagen and too because this zone is an important pass of important line from Berlin, South and East Germany. For all of these reasons the railway line goes through Braunschweig and connects to the city of Wolfsburg first, and after the North-East Germany zone.

Deriving semantic sensor metadata from raw measurements

Sensor network deployments have become a primary source of big data about the real world that surrounds us, measuring a wide range of physical properties in real time. With such large amounts of heterogeneous data, a key challenge is to describe and annotate sensor data with high-level metadata, using and extending models, for instance with ontologies. However, to automate this task there is a need for enriching the sensor metadata using the actual observed measurements and extracting useful meta-information from them. This paper proposes a novel approach of characterization and extraction of semantic metadata through the analysis of sensor data raw observations. This approach consists in using approximations to represent the raw sensor measurements, based on distributions of the observation slopes, building a classi?cation scheme to automatically infer sensor metadata like the type of observed property, integrating the semantic analysis results with existing sensor networks metadata.

Vulnerabilidad sísmica en Puerto Príncipe, Haití. Escala Macrosísmica Haitiana.

Haití, es un país claramente prioritario como receptor de cooperación para el desarrollo. Tras el terremoto del 12 de enero de 2010, se ha desarrollado un Proyecto de Cooperación Interuniversitaria entre la Universidad del Estado de Haití y la Universidad Politécnica de Madrid, financiado por la Agencia Española de Cooperación Internacional para el Desarrollo.El proyecto consiste en la formación y capacitación de los técnicos Haitianos para reconstruir su país. Se está trabajando en la creación de una escala macrosísmica Haitiana, partiendo como base de la Escala Macrosísmica Europea 1998. En este sentido, se hace un análisis exhaustivo de toda la documentación técnica y científica existente hasta la fecha sobre tipos de edificios, clases de vulnerabilidad y grados de daños dependiendo del tipo de edificio. Como caso de estudio se aplica en la ciudad de Puerto Príncipe.En primer lugar se ha clasificado el parque inmobiliario de Puerto Príncipe en diferentes tipologías constructivas, tras un trabajo de campo y teniendo en cuenta las guías de auto-construcción y reparación de edificios publicadas por el Ministerio de Obras Públicas, Transporte y Comunicaciones de Haití. (MTPTC).En el estudio de la vulnerabilidad, además del tipo de estructura de los edificios, se tiene en cuenta la habitabilidad básica que debe tener todo asentamiento humano, analizando no sólo el edificio, sino todo el entorno externo de espacios públicos, infraestructuras, dotaciones y servicios que, en conjunto,conforman el núcleo de cada población y permiten el funcionamiento eficiente del sistema de asentamientos del territorio habitado; pues, en última instancia, dicho territorio construido es el que mejor acota los riesgos ante la vulnerabilidad material y más garantiza la vida saludable de las personas. Los parámetros estudiados son: urbanísticos (anchos de vías, dimensiones de manzanas, trazado, infraestructuras,...), geológicos (estudios del efecto local e identificación de las fallas activas respecto a la edificación) y topográficos (implantación del edificio en zonas llanas, en laderas...). En último lugar, con todos estos datos y los daños registrados en el terremoto de enero de 2010, se hace una escala de intensidades macrosísmica y un plano de ordenación de la vulnerabilidad en Puerto Príncipe, que sirva de base a las autoridades haitianas para la planificación urbanística y la reconstrucción, mitigando de esta manera el riesgo símico. SUMMARY Haiti is a clear priority country as a recipient of development cooperation. After the earthquake of January 12, 2010, an Inter-University Cooperation Project has been developed between the State University of Haiti and the Polytechnic University of Madrid, funded by the Spanish Agency for International Development.The project consists of training and qualifying Haitian technicians to rebuild their country. We are currently working on the creation of a Haitian Macroseismic Scale,based on the European Macroseismic Scale 1998.For the accomplishment of this goal, a comprehensive (deep) analysis is being held, going through all the scientific and technical documentation to date, related to building types, kinds of vulnerability and degrees/ levels of damage depending on the type of building. As a case study, this has been applied to the city of Port-au-Prince.First of all, we have classified the housing typology of Port-au-Prince in different construction types, after carrying on field work in this area and keeping in mind the guidelines for self-construction and repairment of buildings published by the Ministry of Work, Transport and Communications of Haiti. (MTPTC).Regarding the study of vulnerability, besides the type of structure of the buildings, we take into account the basic habitability every human settlement should have, analyzing not only the building, but all the external environment of public spaces,infrastructures, amenities and services, which, as a whole, shape the core of each population and allow the efficient functioning of the settlement system on the inhabited territory. It is this territory,ultimately, the one that better narrows the risks when facing material vulnerability and that better ensures a healthy life for people. The studied parameters are: urban (lane width, block dimensions, layout, infrastructure...), geological (studies focusing on local effects and identification of the active faults in relation to the building) and topographical (implementation of the building on flat areas, slopes...)Finally, with all this data (information) and the registered damages related to the earthquake occurred in 2010, we create a Macroseismic Intensity Scale and a Management Plan of the vulnerability in Port-au-Prince. They will serve as a guideline for Haitians authorities in the urban planning and reconstruction, thus reducing seismic risk.

Cuantificación de las erosión en un talud de Taganana mediante fotogrametría terrestre (Tenerife)

This paper provides an assessment of the potential of terrestrial photogrammetry to calculate erosion associated with surface runoff on hillsides near roads during recent periods. To do this we choose a road embankment located in a valley with hills which have developed abundant grooves erosion. The accuracy of the surveying tool is evident in the evaluation of small hillsides, but is impractical for the study of large hillsides with significant slopes, in which are unknown initial parameters of the topography.

Amplificación del efecto destructivo de los desprendimientos rocosos por deslizamiento sobre suelos volcánicos (Tenerife y Madeira)

This work provides geomorphological and geotechnical observations on the amplification of the destructive behaviour of rock falls developed in rocky slopes with a soil rich in organic matter, which are both exposed to high rainfall regimes. The determinant factor of this process would be related to the low geotechnical quality that the organic matter gives to the soil, which experience a sudden change in its fabric related to the dynamic load, similar to those observed in the quick clays in the fjords of Norway.

Effect of reservoir tillage on rainwater harvesting and soil erosion control under a developed rainfall simulator.

Soil erosion is a serious environmental threat in the Mediterranean region due to torrential rainfalls, and it contributes to the degradation of agricultural land. Techniques such as rainwater harvesting may improve soil water storage and increase agricultural productivity, which could result in more effective land usage. Reservoir tillage is an effective system of harvesting rainwater, but it has not been scientifically evaluated like other tillage systems. Its suitability for the conditions in Spain has not been determined. To investigate and quantify water storage from reservoir tillage and how it could be adapted to improve infiltration of harvested rainwater, a laboratory-scale rainfall simulator was developed. Rainfall characteristics, including rainfall intensity, spatial uniformity and raindrop size, confirm that natural rainfall conditions are simulated with sufficient accuracy. The simulator was auto-controlled by a solenoid valve and three pressure nozzles were used to spray water corresponding to five rainfall intensities ranging from 36 to 112 mm h-1 for 3 to 101-year return period with uniformity coefficients between 83 and 94%. In order to assess the reservoir tillage method under surface slopes of 0, 5, and 10%, three soil scooping devices with identical volume were used to make depressions in the following forms: a) truncated square pyramid, b) triangular prism, and c) truncated cone. These depressions were compared to a control soil surface with no depression. For the loam soil used in this study, results show that reservoir tillage was able to reduce soil erosion and surface runoff and significantly increase infiltration. There was significant difference between the depressions and the control. Compared to the control, depression (a) reduced surface runoff by about 61% and the sediment yield concentration by about 79%.

Flujos de gases de efecto invernadero en suelos forestales y agroforestales del centro de la Península Ibérica=Greenhouse gas flows in forest and agroforestry soils in the center of the Iberian Peninsula

Debido a la complejidad de los procesos que controlan el intercambio de gases de carbono (C) y nitrógeno (N) entre el suelo y la atmósfera, en los sistemas forestales y agroforestales, son comprensibles las incógnitas existentes respecto a la estimación de los flujos de los gases de efecto invernadero (GEI) y la capacidad como reservorios de carbono de los suelos, bajo diferentes formas de uso y regímenes de alteración a escala regional y global. Esta escasez de información justifica la necesidad de caracterizar la dinámica de intercambio de GEI en los ecosistemas Mediterráneos, en especial en el contexto actual de cambio climático, y el incremento asociado de temperatura y periodos de sequía, alteración de los patrones de precipitación, y el riesgo de incendios forestales; cuyas consecuencias afectarán tanto a los compartimentos de C y de N del suelo como a la capacidad de secuestro de C de estos ecosistemas. Dentro de este contexto se enmarca la presente tesis doctoral cuyo objetivo ha sido cuantificar y caracterizar los flujos de dióxido de carbono (CO2), de oxido nitroso (N2O) y de metano (CH4), junto con los stocks de C y N, en suelos forestales de Quercus ilex, Quercus pyrenaica y Pinus sylvestris afectados por incendios forestales; así como el estudiar el efecto de la gestión y la cubierta arbórea en la respiración del suelo y los stocks de C y N en una dehesa situada en el centro de la Península Ibérica. De manera que los flujos de CO2, N2O y CH4; y los parámetros físico-químicos y biológicos del suelo fueron estudiados en los diferentes tratamientos y ecosistemas a lo largo del trabajo que se presenta. Los resultados obtenidos muestran la existencia de variaciones temporales y espaciales de la respiración del suelo dentro de una escala geográfica pequeña, controladas principalmente por la temperatura y la humedad del suelo; y por los contenidos de C y N del suelo en un bosque de Pinus sylvestris en la vertiente norte de la Sierra de Guadarrama , en España. El análisis de los efectos de los incendios forestales a largo plazo (6-8 años) revela que las pérdidas anuales de C a través de la respiración del suelo en las zonas quemadas de Quercus ilex, Quercus pyrenaica y Pinus sylvestris fueron 450 gCm-2yr-1, 790 gCm-2yr-1 y 1220 gCm-2yr-1, respectivamente; lo que representa una reducción del 43%, 22% y 11% en comparación con las zonas no quemadas de dichas especies, debido a la destrucción de la masa arbórea. El efecto del fuego también alteró los flujos N2O y CH4 del suelo, de una forma diferente en los distintos ecosistemas y estacionalidades estudiadas. De tal modo, que los suelos quemados mostraron una mayor oxidación del CH4 en las masas de Q. ilex, y una menor oxidación en las de P. sylvestris; además de una disminución de los flujos de N2O en Q. pyrenaica. Los incendios también afectaron los parámetros microclimáticos de los suelos forestales, observándose un incremento de la temperatura del suelo y una disminución de la humedad en los emplazamientos quemados que en los no quemados. Los cationes intercambiables, el pH, el cociente C/N, el contenido en raicillas y la biomasa microbiana también disminuyeron en las zonas quemadas. Aunque el C orgánico del suelo no se alteró de manera significativa, si lo hizo la calidad de la materia orgánica, disminuyendo el carbono lábil y aumentando las formas recalcitrantes lo que se tradujo en menor sensibilidad de la respiración del suelo a la temperatura (valores de Q10) en las zonas quemadas. Los resultados del estudio realizado en la Dehesa muestran que las actividades silvopastorales estudiadas afectaron levemente y de forma no constante a la respiración del suelo y las condiciones microclimáticas del suelo. Se observó una reducción 12% de la respiración del suelo por efecto del pastoreo no intensivo. Sin embargo, se observaron incrementos de 3Mg/ha en los stocks de C y de 0.3 Mg/ha en los stocks de N en los suelos pastoreados en comparación con los no pastoreados. Aunque, no se observó un claro efecto de la labranza sobre la respiración del suelo en nuestro experimento, sin embargo si se observó una disminución de 3.5 Mg/ha en las reservas de C y de 0.3 Mg/ ha en las de N en los suelos labrados comparados con los no labrados. La copa del arbolado influyó de forma positiva tanto en la respiración del suelo, como en los stocks de C y N de los suelos. La humedad del suelo jugó un papel relevante en la sensibilidad de la respiración a la temperatura del suelo. Nuestros resultados ponen de manifiesto la sensibilidad de la respiración del suelo a cambios en la humedad y los parámetros edáficos, y sugieren que la aplicación de modelos estándar para estimar la respiración del suelo en áreas geográficas pequeñas puede no ser adecuada a menos que otros factores sean considerados en combinación con la temperatura del suelo. Además, las diferentes respuestas de los flujos de gases de efecto invernadero a los cambios, años después de la ocurrencia de incendios forestales, destaca la necesidad de incluir estos cambios en las futuras investigaciones de la dinámica del carbono en los ecosistemas mediterráneos. Por otra parte, las respuestas divergentes en los valores de respiración del suelo y en los contenidos de C y N del suelo observados en la dehesa, además de la contribución de la copa de los árboles en los nutrientes del suelo ilustran la importancia de mantener la gestión tradicional aplicada en beneficio de la capacidad de almacenar C en la dehesa estudiada. La información obtenida en este trabajo pretende contribuir a la mejora del conocimiento de la dinámica y el balance de C en los sistemas mediterráneos, además de ayudar a predecir el impacto del cambio climático en el intercambio de C entre los ecosistemas forestales y agroforestales y la atmósfera. ABSTRACT Due to the complexity of the processes that control the exchange of carbon (C) and nitrogen (N) gasses between soils and the atmosphere in forest and agroforestry ecosystems, understandable uncertainties exist as regards the estimation of greenhouse gas (GHG) fluxes and the soil sink capacity at regional and global scale under different forms of land use and disturbance regimes. These uncertainties justify the need to characterize the exchange dynamics of GHG between the atmosphere and soils in Mediterranean terrestrial ecosystems, particularly in the current context of climate change and the associated increase in temperature, drought periods, heavy rainfall events, and increased risk of wildfires, which affect not only the C and N pools but also the soil C sink capacity of these ecosystems. Within this context, the aims of the present thesis were, firstly, to quantify and characterize the fluxes of carbon dioxide (CO2), nitrous oxide (N2O) and methane (CH4) as well as the C and N stocks in Quercus ilex, Quercus pyrenaica and Pinus sylvestris stands affected by wildfires, and secondly, to study the effects of Quercus ilex canopy and management on both soil respiration and C and N pools in dehesa systems in the center of Iberian Peninsula. Soil CO2, N2O and CH4 fluxes, and soil physical-chemical and biological parameters were studied under the different treatments and ecosystems considered in this study. The results showed seasonal and spatial variations in soil respiration within small geographic areas, mainly controlled by soil temperature and moisture in addition to soil carbon and nitrogen stocks in mixed pine–oak forest ecosystems on the north facing slopes of the Sierra de Guadarrama in Spain. The analysis of long term effects of wildfires (6–8 years) revealed that annual carbon losses through soil respiration from burned sites in Quercus ilex, Quercus pyrenaica and Pinus sylvestris stands were 450 gCm-2yr-1, 790 gCm-2yr-1 and 1220 gCm-2yr-1, respectively; with burned sites emitting 43%, 22% and 11% less in burned as opposed to non-burned sites due the loss of trees. Fire may alter both N2O and CH4 fluxes although the magnitude of such variation depends on the site, soil characteristics and seasonal climatic conditions. The burned sites showed higher CH4 oxidation in Q.ilex stands, and lower oxidation rates in P. sylvestris stands. A reduction in N2O fluxes in Q. pyrenaica stands was detected at burned sites along with changes in soil microclimate; higher soil temperature and lower soil moisture content. Exchangeable cations, the C/N ratio, pH, fine root and microbial biomass were also found to decrease at burned sites. Although the soil organic carbon was not significantly altered, the quality of the organic matter changed, displaying a decrease in labile carbon and a relative increase in refractory forms, leading to lower sensitivity of soil respiration to temperature (Q10 values) at burned sites. The results from the dehesa study show that light grazing and superficial tilling practices used in the studied dehesa system in Spain had a slight but non-consistent impact on soil respiration and soil microclimate over the study period. The reduction in soil respiration in the dehesa system due to the effects of grazing was around 12 %. However, increments of 3Mg/ha in C stocks and 0.3 Mg/ha in N stocks in grazed soils were observed. Although no clear effect of tilling on soil respiration was found, a decrease of 3.5 Mg/ha in C stocks and 0.3 Mg/ha in N stocks was detected for tilled soils. The presence of a tree canopy induced increases in soil respiration, soil C and N stocks, while soil moisture was found to play an important role in soil respiration temperature response. Our results suggest that the use of standard models to estimate soil respiration in small geographical areas may not be adequate unless other factors are considered in addition to soil temperature. Furthermore, the different responses of GHG flux to climatic shifts, many years after the occurrence of wildfire, highlight the need to include these shifts in C dynamics in future research undertaken in Mediterranean ecosystems. Furthermore, divergent responses in soil respiration and soil C and N stocks to grazing or tilling practices in Dehesa systems, and the influence of tree canopy on soil respiration and soil nutrient content, illustrate the importance of maintaining beneficial management practices. Moreover, the carbon sequestration capacity of the Dehesa system studied may be enhanced through improvements in the management applied. It is hoped that the information obtained through this research will contribute towards improving our understanding of the dynamics and balance of C in Mediterranean systems, and help predict the impact of climate change on the exchange of C between forest and agroforestry ecosystems and the atmosphere.

Modelling Human Displacement through Movement Surfaces.

This paper introduces a new approach for predicting people displacement by means of movementsurfaces. These surfaces can allow the simulation of a person?s movement through the use of semanticmovement concepts such as those making up the environment, the people who are moving, eventsthat describe a human activity, and time of occurrences. In order to represent this movement we havetransformed the trajectory of a person or group of persons into a raindrop path over a surface. As araindrop flows over a surface looking for the maximum slopes, people flow over the landscapelooking for the maximum utility. The movement surfaces are the response to a chained succession of events describing the way a person moves from one destination to another passing through the mostaffine trajectory to his interest. The three construction phases of this modelling approach (exploration,reasoning and prediction) are presented in this paper. The model was implemented in Protégé and aJava application was developed to generate the movement surface based on a recreational scenario.The results had shown the opportunity to apply our approach to optimise the accessibility of recreational areas according to the preferences of the users of that location.

Estimate of the total ice volume of Svalbard glaciers and their potential contribution to sea-level rise = Estimación del volumen de hielo de Svalbard y su contribución potencial a la subida del nivel del mar

El objetivo final de las investigaciones recogidas en esta tesis doctoral es la estimación del volumen de hielo total de los ms de 1600 glaciares de Svalbard, en el Ártico, y, con ello, su contribución potencial a la subida del nivel medio del mar en un escenario de calentamiento global. Los cálculos más exactos del volumen de un glaciar se efectúan a partir de medidas del espesor de hielo obtenidas con georradar. Sin embargo, estas medidas no son viables para conjuntos grandes de glaciares, debido al coste, dificultades logísticas y tiempo requerido por ellas, especialmente en las regiones polares o de montaña. Frente a ello, la determinación de áreas de glaciares a partir de imágenes de satélite sí es viable a escalas global y regional, por lo que las relaciones de escala volumen-área constituyen el mecanismo más adecuado para las estimaciones de volúmenes globales y regionales, como las realizadas para Svalbard en esta tesis. Como parte del trabajo de tesis, hemos elaborado un inventario de los glaciares de Svalbard en los que se han efectuado radioecosondeos, y hemos realizado los cálculos del volumen de hielo de más de 80 cuencas glaciares de Svalbard a partir de datos de georradar. Estos volúmenes han sido utilizados para calibrar las relaciones volumen-área desarrolladas en la tesis. Los datos de georradar han sido obtenidos en diversas campañas llevadas a cabo por grupos de investigación internacionales, gran parte de ellas lideradas por el Grupo de Simulación Numérica en Ciencias e Ingeniería de la Universidad Politécnica de Madrid, del que forman parte la doctoranda y los directores de tesis. Además, se ha desarrollado una metodología para la estimación del error en el cálculo de volumen, que aporta una novedosa técnica de cálculo del error de interpolación para conjuntos de datos del tipo de los obtenidos con perfiles de georradar, que presentan distribuciones espaciales con unos patrones muy característicos pero con una densidad de datos muy irregular. Hemos obtenido en este trabajo de tesis relaciones de escala específicas para los glaciares de Svalbard, explorando la sensibilidad de los parámetros a diferentes morfologías glaciares, e incorporando nuevas variables. En particular, hemos efectuado experimentos orientados a verificar si las relaciones de escala obtenidas caracterizando los glaciares individuales por su tamaño, pendiente o forma implican diferencias significativas en el volumen total estimado para los glaciares de Svalbard, y si esta partición implica algún patrón significativo en los parámetros de las relaciones de escala. Nuestros resultados indican que, para un valor constante del factor multiplicativo de la relacin de escala, el exponente que afecta al área en la relación volumen-área decrece según aumentan la pendiente y el factor de forma, mientras que las clasificaciones basadas en tamaño no muestran un patrón significativo. Esto significa que los glaciares con mayores pendientes y de tipo circo son menos sensibles a los cambios de área. Además, los volúmenes de la población total de los glaciares de Svalbard calculados con fraccionamiento en grupos por tamaño y pendiente son un 1-4% menores que los obtenidas usando la totalidad de glaciares sin fraccionamiento en grupos, mientras que los volúmenes calculados fraccionando por forma son un 3-5% mayores. También realizamos experimentos multivariable para obtener estimaciones óptimas del volumen total mediante una combinación de distintos predictores. Nuestros resultados muestran que un modelo potencial simple volumen-área explica el 98.6% de la varianza. Sólo el predictor longitud del glaciar proporciona significación estadística cuando se usa además del área del glaciar, aunque el coeficiente de determinación disminuye en comparación con el modelo más simple V-A. El predictor intervalo de altitud no proporciona información adicional cuando se usa además del área del glaciar. Nuestras estimaciones del volumen de la totalidad de glaciares de Svalbard usando las diferentes relaciones de escala obtenidas en esta tesis oscilan entre 6890 y 8106 km3, con errores relativos del orden de 6.6-8.1%. El valor medio de nuestras estimaciones, que puede ser considerado como nuestra mejor estimación del volumen, es de 7.504 km3. En términos de equivalente en nivel del mar (SLE), nuestras estimaciones corresponden a una subida potencial del nivel del mar de 17-20 mm SLE, promediando 19_2 mm SLE, donde el error corresponde al error en volumen antes indicado. En comparación, las estimaciones usando las relaciones V-A de otros autores son de 13-26 mm SLE, promediando 20 _ 2 mm SLE, donde el error representa la desviación estándar de las distintas estimaciones. ABSTRACT The final aim of the research involved in this doctoral thesis is the estimation of the total ice volume of the more than 1600 glaciers of Svalbard, in the Arctic region, and thus their potential contribution to sea-level rise under a global warming scenario. The most accurate calculations of glacier volumes are those based on ice-thicknesses measured by groundpenetrating radar (GPR). However, such measurements are not viable for very large sets of glaciers, due to their cost, logistic difficulties and time requirements, especially in polar or mountain regions. On the contrary, the calculation of glacier areas from satellite images is perfectly viable at global and regional scales, so the volume-area scaling relationships are the most useful tool to determine glacier volumes at global and regional scales, as done for Svalbard in this PhD thesis. As part of the PhD work, we have compiled an inventory of the radio-echo sounded glaciers in Svalbard, and we have performed the volume calculations for more than 80 glacier basins in Svalbard from GPR data. These volumes have been used to calibrate the volume-area relationships derived in this dissertation. Such GPR data have been obtained during fieldwork campaigns carried out by international teams, often lead by the Group of Numerical Simulation in Science and Engineering of the Technical University of Madrid, to which the PhD candidate and her supervisors belong. Furthermore, we have developed a methodology to estimate the error in the volume calculation, which includes a novel technique to calculate the interpolation error for data sets of the type produced by GPR profiling, which show very characteristic data distribution patterns but with very irregular data density. We have derived in this dissertation scaling relationships specific for Svalbard glaciers, exploring the sensitivity of the scaling parameters to different glacier morphologies and adding new variables. In particular, we did experiments aimed to verify whether scaling relationships obtained through characterization of individual glacier shape, slope and size imply significant differences in the estimated volume of the total population of Svalbard glaciers, and whether this partitioning implies any noticeable pattern in the scaling relationship parameters. Our results indicate that, for a fixed value of the factor in the scaling relationship, the exponent of the area in the volume-area relationship decreases as slope and shape increase, whereas size-based classifications do not reveal any clear trend. This means that steep slopes and cirque-type glaciers are less sensitive to changes in glacier area. Moreover, the volumes of the total population of Svalbard glaciers calculated according to partitioning in subgroups by size and slope are smaller (by 1-4%) than that obtained considering all glaciers without partitioning into subgroups, whereas the volumes calculated according to partitioning in subgroups by shape are 3-5% larger. We also did multivariate experiments attempting to optimally predict the volume of Svalbard glaciers from a combination of different predictors. Our results show that a simple power-type V-A model explains 98.6% of the variance. Only the predictor glacier length provides statistical significance when used in addition to the predictor glacier area, though the coefficient of determination decreases as compared with the simpler V-A model. The predictor elevation range did not provide any additional information when used in addition to glacier area. Our estimates of the volume of the entire population of Svalbard glaciers using the different scaling relationships that we have derived along this thesis range within 6890-8106 km3, with estimated relative errors in total volume of the order of 6.6-8.1% The average value of all of our estimates, which could be used as a best estimate for the volume, is 7,504 km3. In terms of sea-level equivalent (SLE), our volume estimates correspond to a potential contribution to sea-level rise within 17-20 mm SLE, averaging 19 _ 2 mm SLE, where the quoted error corresponds to our estimated relative error in volume. For comparison, the estimates using the V-A scaling relations found in the literature range within 13-26 mm SLE, averaging 20 _ 2 mm SLE, where the quoted error represents the standard deviation of the different estimates.