A new approach for assessing natural patterns of flow variability and hydrological alterations: The case of the Spanish rivers

Ensuring water is available for human use usually requires dams and reservoirs that severely affect river ecosystems. Hydrological alteration by river damming represents one of the most prominent human impacts on freshwater ecosystems. This paper presents a methodological approach to assessing the natural patterns of flow variability and hydrological alterations in Mediterranean rivers. The methodology first defines the admissible range of flow variability under a natural flow regime. Then, the methodology measures the environmental impact of flow regulation according to the inferred hydrological alteration and classifies rivers into homogeneous groups according to the magnitude, frequency, duration and seasonality of the impacts. This paper applies the proposed methodology to thirty-three river segments below large reservoirs located in the three largest Spanish watersheds (Duero, Ebro and Tajo). For each segment, this study evaluates the general impoundment characteristics and geographical contexts and calculates the flow impacts and the divergence between the circulating flows and the reference area of admissible flow variability on a daily basis for the period 2000 2010. This assessment of dam regulation impacts provides a reference to plan measures for mitigating these impacts. The advantages of this flow regulation impact analysis over other analyses are discussed in terms of the implementation of environmental water costs as suggested by the European Water Framework Directive. This approach expands the current understanding of water environmental costs and represents a practical management tool for decreasing the environmental impacts of flow regulation and for increasing water-use efficiency. (c) 2018 Elsevier Lt

Insignificance and Minor Architecture

The fragmented condition of our everyday brings us closer to the risks of hyper-expression. Against it two positions unfold to help us face a world that escapes our capacities: familiarity and poetic recognition. In the latter it is crucial the role of the insignificant as dynamic and relational instigator of a conscious threading of reality through the actions of the Poeta Faber and his careful look onto the world. / The production of the common as the material and symbolic fabric of the city, unstable reality in a perpetual becoming, leads us to a new and much needed reconsideration of the public/private division born from the modern state. Immersed in the confusion between public and common, we have not perceived that through the expropriation of the first we have been prepared for the willing surrendering of the second. / From insignificance to rebellion as affirmative going into action related to the idea of minor architecture as common and intensely political production, born from the inside of a society that has no more outsides

Acrobats in the rooftops of Tehran

This paper seeks to analyze the political dimension of the body, and consequently the inherently political dimension of space, through the instrumental notion of situation, understood as an spatio-temporal mesh configured by bodies, practices and discourses. The political understood as the potential for action (or non-action) underlying the individual body, implies a renewed definition of a landscape that results from the body’s doing. Landscape becomes a multiple corporeality, a field of relations in which we discover ourselves enmeshed, not just placed; a field in which the limit is not frontier but bond and common dimension. A disquieting ambiguous zone appears there where the individual spatiality is born out of the body through the actualization of its political potential and entangles with others to constitute a common spatiality, political action of the multitude. The article is organized through the description of a back-and-forth movement between the revolts of Tehran in 2009 and the Iranian revolution of 1979. Also, a detour into the works of Robert Morris and Trisha Brown is required in order to understand the link between the body and the constitution of a common spatiality

Roofscapes and the spatiality of the common

The relationship between forms of delimitation and expropriation of the commons through the management of the "public" have led to a world of enclosures and exact division lines. But this is not how the individual perceives and experiences space, this is how bureaucracy builds it. The body’s individual spatiality is understood as the complex topological extension configured by the sensible world at every turn, reflecting while allowing the crossings, junctions, intensities, densities, proximities, etc., which weave together the experiential fabric wherein he lives. This individual spatiality, when it resonates with others, produces a form of common spatiality, the understanding of which can and should act as a new frame of reference for intervention strategies and spatial politics in the contemporary world. The roofscape, as a space not fitting within the canonical division of public/private, is a unique study case to frame these new concepts

Estimación de caudales óptimos y mínimos para el uso del Raft en el Alto Tajo

La creciente demanda de usos recreativos en los ríos y en especial de las actividades náuticas, tanto competitivas como de turismo activo, exige una respuesta razonada en cuanto a las necesidades de caudales circulantes por los ríos. Las Confederaciones Hidrográficas como gestoras del recurso “agua” deben coordinar las diferentes demandas del uso de este recurso en base a unas exigencias razonadas de los diferentes usuarios. En este trabajo presentamos por primera vez en España una metodología adaptada a las necesidades de este tipo de usos recreativos. Esta metodología se basa en la estimación de unos parámetros de uso que evalúan las capacidades de los cauces de los ríos, aplicando un programa informático que nos permite calcular caudales óptimos y mínimos para el uso recreativo por simulación de las condiciones hidráulicas del cauce bajo el supuesto de diferentes caudales circulantes por el mismo

Reiteraciones: ritmo y diseminación en Génesis 1,1-2,4a

 PRELIMINARES. I. LA SECCIÓN CENTRAL. 1. La disposición rítmica de Génesis 1,3-31. 1.1. Ritmo. 1.2. Diseminación. 2. Una hipótesis sobre el procedimiento de construcción de Génesis 1,3-31. 3. El sentido de la presencia de los elementos rítmicos y de los diseminados. 3.1. La presencia de los días. 3.2. La presencia de las acciones. 3.2.1. Las seis acciones centrales. 3.2.2. Las dos acciones marginales. 3.3. La estructura de cada acción creadora. 3.3.1. «Y dijo Dios». 3.3.2. «Y fue así». 3.3.3. Las operaciones con las que Dios crea. 3.3.4. «Y llamó». «Y vio». 4. Progresión temática. II. LAS SECCIONES MARGINALES. CONCLUSIONES

Estimació de cabals òptims i mínims per a l’ús del ràfting a l’Alt Tajo

La creixent demanda d’usos recreatius en els rius i de forma especial de les activitats nàutiques, tant competitives com de turisme actiu, exigeix una resposta raonada pel que fa a les necessitats de cabals circulants pels rius. Les Confederacions Hidrogràfiques, com a gestores del recurs “aigua”, han de coordinar les diferents demandes de l’ús d’aquest recurs tenint en compte unes exigències raonades dels diferents usuaris. En aquest treball presentem per primera vegada a Espanya una metodologia adaptada a les necessitats d’aquest tipus d’usos recreatius. Aquesta metodologia es basa en l’estimació d’uns paràmetres d’ús que avaluen les capacitats de les lleres dels rius, aplicant un programa informàtic que ens permet de calcular cabals òptims i mínims per a l’ús recreatiu, per simulació de les condicions hidràuliques del llit fluvial en el supòsit de diferents cabals circulant per la llera

Génesis 3, 1-6. Era la serpiente la mas astuta alimaña que Dios hizo.

La disposición dialógica de la tentación que da lugar al primer pecado cumple una decisiva función argumental en Gn 2-3. Siguiendo la tónica general del relato, expresa el carácter peculiar, diferenciado y armónico de cada una de las obras de la creación, exime a Dios de cualquier responsabilidad en el origen del mal y atenúa la culpabilidad del ser humano. Al mismo tiempo, ratifica la condición histórica de éste, siempre obligado a decidir sobre su suerte, e insinúa que también la actuación de Dios es respuesta a la historia humana. Este factor cobra especial relevancia para interpretar el sentido que tiene la promesa de la Redención

Attributes for assessing the environmental quality of riparian zones

Seven attributes of riparian systems are proposed to be considered for assessing the ecological status of riparian zones. They can be easily evaluated by taking into consideration some features of the structure and functioning of riverine systems, largely determined by their hydromorphological dynamics. The structure of riparian zones could be characterized by the longitudinal continuity of vegetation, the lateral dimensions (width) of the channel containing natural riparian vegetation and the composition and structure of riparian vegetation communities. These attributes basically define the morphology of riparian areas, reflecting a static view of the river. They also define the spatial dimensions where riparian functions take place, indicating the possibilities of carrying on riparian restoration activities at short time scales.The functioning of riparian systems may be assessed considering the ratio of natural woody species regeneration, bank conditions, lateral connectivity and permeability of riparian soils. These attributes indicate the temporal behaviour of riparian zones, that is showed in a more dynamic or video view of the river. They are more related to the potential of achieving riparian restoration at longer time scales, representing key elements to guarantee the self-maintenance of fluvial processes and riparian biodiversity. The aforementioned attributes provide a framework to assess the ecological status of riparian zones, and offer a minimum checklist of criteria to evaluate strategies for restoring and preserving river ecosystems.El estado ecológico de las riberas fluviales puede quedar caracterizado a través de siete atributos. Dichos atributos pueden ser fácilmente evaluados teniendo en cuenta diferentes aspectos de la estructura y del funcionamiento de los sistemas riparios, los cuales están fuertemente determinados por la dinámica hidromorfológica fluvial. La estructura de las riberas queda caracterizada por la continuidad longitudinal de la vegetación, las dimensiones laterales (anchura) del espacio fluvial conteniendo vegetación riparia natural y la composición y estructura de las comunidades vegetales riparias. Estos atributos definen básicamente la morfología de las riberas, y quedan reflejados en una visión estática o fotografía del río. A su vez, dichos atributos definen las dimensiones espaciales donde tienen lugar las funciones riparias, e indican las posibilidades de llevar a cabo la restauración fluvial a corto plazo. El funcionamiento de los sistemas riparios queda reflejado a través de la tasa de regeneración natural de las especies leñosas riparias, la condición de las orillas, la conectividad lateral del cauce con sus riberas y la permeabilidad de los suelos riparios. Estos atributos indican el comportamiento en el tiempo de las riberas, y su evaluación requiere una visión dinámica, reflejada en un vídeo del río. Dichos atributos están más relacionados con las posibilidades de lograr la restauración fluvial a más largo plazo, representando elementos claves para garantizar la sostenibilidad de los procesos fluviales y la biodiversidad de los sistemas riparios. Los atributos mencionados representan en su conjunto un esquema para evaluar el estado ecológico de las riberas fluviales, y sirven como criterios para evaluar las propuestas de estrategias de restauración y conservación de los ecosistemas fluviales

Responses of sub-Saharan smallholders to climate change: Strategies and drivers of adaptation

Rural farm households in sub-Saharan Africa are vulnerable to climate variability due to their limited adaptive capacity. This paper explores how adaptation strategies are adopted by small-holders in sub-Saharan Africa as a function of their adaptive capacity. The latter is characterised by five types of capital: natural, physical, financial, human, and social. We use responses from farm households in sub-Saharan Africa dating from 1536 obtained by Climate Change, Agriculture and Food Security (CCAFS). This data provides information on the adoption of adaptation practices during the study period as well as information with which we develop indicators for the five types of capital. The results suggest that all the five types of capital positively influence adoption of adaptation practices. Human and social capital both displayed a positive and significant effect on the uptake of most adaptation practices. This finding suggests that the effect of less tangible kinds of capital such as knowledge, individual perceptions, farmers networks and access to information may be stronger than normally assumed. Directing more development policies towards enhancing human and social capital may therefore be more cost-effective than further investments into physical and financial capital, and could help in overcoming social barriers to adaptation to climate change. (c) 2018 Elsevier LtdMarc B. Neumann acknowledges financial support from the Ramón y Cajal Fellowship of the Ministry of Economy and Competitiveness of Spain (no. RYC-2013-13628 )