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Los grupos de trabajo son centrales en las organizaciones actuales, y uno de los procesos más relevantes es el aprendizaje de equipo, su desarrollo y sus antecedentes. El presente estudio tiene dos objetivos principales: 1) analizar el efecto del clima del grupo sobre el desarrollo del aprendizaje de equipo y 2) estudiar el rol modulador de diferentes estresores de equipo (sobrecarga y presión temporal) en dicha relación. Los resultados muestran que el clima del equipo influye de manera concurrente y diferida sobre el aprendizaje. La sobrecarga de trabajo modula la relación entre el apoyo a la innovación y el aprendizaje de equipo al inicio del trabajo en grupo. Sin embargo, la presión temporal no parece tener efectos en dicha relación. Teams are central work units in organizations. One of the processes that are receiving attention is team learning. The focus is on those processes that can predict team learning and its evolution over time. This study has two objectives. First, analyze team climate effect on team learning development. Second, test the moderator role of team stressors (work overload and time pressure) in the relationship between tem climate and team learning. Results obtained shows that team climate have concurrent and differed effects on team learning. On the other hand, work overload moderates the relationship between support for innovation and team learning at the beginning of teamwork, but time pressure does not have effects in the relationship between team climate and team learning.

This paper concerns with a description of the variations in the disturbance depth across four open mesotidal beaches in the Cadiz littoral (SW Spain), along single tidal cycles, using rods and cores of marked beach sands inserted in the foreshore. The studied beaches show a quite wide range of morphologies, from reflective and barred dissipative to pure dissipative ones. Nevertheless, the energetic conditions of the coast remain more or less constant along its length. In this work the recorded disturbance depths have been compared with parameters like wave height, beach gradient and grain size distribution. As a conclusion, it has been obtained that the morphodynamic regime is the characteristic that better explains the spatial variation of the disturbance depth, as well as the different response of the beaches under broadly similar energetic conditions. In each case the morphodynamic situation controls the distribution and relative intensity of wave processes acting across the beach profile and, hence, the different rate of disturbance depth. The morphodynamic study of a beach permits an initial prediction of its morphological response under variable wave conditions.El estudio de la profundidad de removilización durante un ciclo mareal es importante para conocer la morfodinámica de las playas. En el presente estudio se han considerado cuatro playas mesomareales del litoral de la provincia de Cádiz (SO de España), utilizando varillas y testigos insertados en la zona intermareal. La morfología de las playas estudiadas es muy variada, existiendo playas reflectivas, disipativas con barra y disipativas en sentido estricto. No obstante, las condiciones energéticas de la costa son bastante homogéneas y se mantienen relativamente constantes a lo largo de su extensión. En este trabajo se han comparado los valores de removilización registrados con los parámetros de altura de ola, pendiente de la playa y distribución del tamaño de grano. Como conclusión, se ha obtenido que el tipo de rompiente es el factor que mejor explica la variación espacial de la profundidad de removilización, así como la respuesta diferencial de las playas ante condiciones energéticas inicialmente similares. En cada caso la situación morfodinámica controla la distribución y la intensidad relativa de los procesos de oleaje que actúan en el perfil de la playa y, por lo tanto, el diferente valor de la profundidad de removilización. El estudio morfodinámico de una playa permite así predecir su respuesta morfológica bajo condiciones de oleaje variables.

Aerial photographs and historical records have been analyzed to reconstruct the coastal evolution in recent times, while the erosive processes acting in the short term have been studied by means of a field monitoring program. Both working techniques do not always provide the same results and they must be combined for a realistic knowledge of the erosiona! state of the coast. In the Culf of Cádiz two main causes produce coastal erosion: the construction of dams in fluvial basins and the building of coastal engineering structures. A map of morpho-erosive states has been made for the Bay of Cádiz, based on the results of the beach monitoring program and the morphometric measurements made on aerial photographs

Theoretical and empirical estimations of the longshore sediment transport were applied to a beach in the northern Cádiz Bay. In the first case, several predictive models were applied by combining energetic, morphological and sedimentological characteristics of the beach. In the second case, a field experiment was been carried out by injecting tracers in the beachface, with a later sampling permitted to determine the displacement of the centre of mass. At the same time, remobilization depth was quantified by using rods and sticks. As a conclusion, it can be stated that the models give super-estimations of the real amount of transported sediment measured in the field. This contradiction confirms the limited applicability of these kind of predictive models in a low energy coast like this

Theoretical and empirical estimations of the longshore sediment transport were applied to a beach in the northern Cádiz Bay. In the first case, several predictive models were applied by combining energetic, morphological and sedimentological characteristics of the beach. In the second case, a field experiment was been carried out by injecting tracers in the beachface, with a later sampling permitted to determine the displacement of the centre of mass. At the same time, remobilization depth was quantified by using rods and sticks. As a conclusion, it can be stated that the models give super-estimations of the real amount of transported sediment measured in the field. This contradiction confirms the limited applicability of these kind of predictive models in a low energy coast like this

The identification and dating of Holocene marine tenaces in the southern Bay of Cádiz has allowed the reconstruction of its recent coastal evolution. Since the Flandrian maximum was reached in the Bay, about 5000 years ago, a sea level fall is deduced for the Upper Holocene. The consequences of this process consisted in a rapid sedimentary progradation in estuarine/marshland environments and a progressive continentalization of former coastal areas. Meanwhile, the exposed sandy coastline has suffered a severe retreat in some points during recent times, due to several causes, both natural (very energetic marine processes, like historical tsunami or storm waves) and anthropic (construction of dams in the fluvial basins affluent to the bay)

Three basic remarkable types of submarine forms have been Identified, from high resolution seismic profiling in the Northwestern continental margin of the Alboran Sea: Submarine Terraces, Terraces + Small Prograding Bodies and Important Prograding Bodies. Their morphometric analysis shows repetitive sequences in their bathymetric distribution. These sequences are related to three types of eustatic cycles at different scales, all of them included within the general trend of relative sea level rise that occurred upon the margin through the last 20.000 years

[Resumen] En el presente trabajo se estudian los efectos que los temporales de Diciembre e 1995 y Enero de 1996 tuvieron sobre las playas de la Bahía de Cádiz. Del análisis del oleaje incidente se observa cómo sus efectos se multiplican cuando los picos de temporal coinciden con el máximo rango de mareas. Los cambios morfológicos registrados en las playas se estudian mediante el perfilamiento pre y post-temporal de playas tanto naturales como regeneradas artificialmente. La cuantificación de dichos cambios muestra cómo la forma inicial de los perfiles es determinante en el tipo de respuesta de las playas frente a olejaes de gran energía. También se manifiestan procesos de erosión en cordones dunares, mediante incisiones, desbordamientos, etc. La estimación final de los daños sufridos por las playas revela mayores pérdidas en aquellas zonas donde la presión antrópica es mayor [Abstract] The work deals with the effects that the storm surges of December-1995 and January-1996 made upon the beaches of Cádiz Bay (SW Spain). From the incidentwave analysis it can be deduced that the effects are much stronger when the surge peak coincides with maximum tidal ranges. The morphological changes recorded in the beaches are studied through pre- and post-surge profiling of both natural and artificially nourished beaches. The quantification of such morphological transformations shows that the initial beach profile is determinant in the kind of response of the beach to high wave-energy conditions. The erosive processes upon dune ridges are represented by gullying, overwashing, etc. The final estimation of losses in the beaches reveals higher damages in zones where anthropic preassure is higher.

Three basic remarkable types of submarine forms have been Identified, from high resolution seismic profiling in the Northwestern continental margin of the Alboran Sea: Submarine Terraces, Terraces + Small Prograding Bodies and Important Prograding Bodies. Their morphometric analysis shows repetitive sequences in their bathymetric distribution. These sequences are related to three types of eustatic cycles at different scales, all of them included within the general trend of relative sea level rise that occurred upon the margin through the last 20.000 years

The Daroca Graben was generated in Pliocene times, being filled by detritic sediments of Pliocene s.l. age. These deposits are afected by normal faults and by the renewed movement of the main fau/t that limits the NE border of the graben. Such dislocations are fossilized by plioquaternary alluvial fans, which permit us define a distensive tectonic episode at the fina/ Pliocene (Darocian Phase). The distensive tectonic activity has continued during quaternary times, although with a lesser intensity, La Fosa de Daroca se originó en el Plioceno debido al depósito de sedimentos de edad Plioceno s.l. Estos depósitos se ven afectados por fallas normales y por el movimiento renovado de la falla principal que limita con el borde NE de la fosa. Estas dislocaciones están fosilizadas por abanicos aluviales pliocuaternarios, que nos permiten definir un episodio tectónico distensivo al final del Plioceno (Fase Darocense). La actividad tectónica distensiva ha continuado durante el cuaternario, aunque con menor intensidad.

The aim of the present paper is to compare the profile response of two mesotidal beaches (Faro, 10 km long, Algarve; La Barrosa, 8 km long, Cadiz) within a single regional physiographic unit (the Gulf of Cadiz) to the same storm event (January, 1996). For this comparison, a series of beach surveys was used, including a total of 10 study sites, five at each study area. The two beaches belong to exposed, mesotidal, sandy shores, and have a similar coastal orientation. However, the response time-scale is different for each one. Faro showed a total amount of 130 000 m³ of erosion due to the storm, with a complete post-storm recovery after one tidal cycle. La Barrosa had a total sand loss of 80 000 m³ due to the storm, with a final recovery of 60 000 m³, 4-6 months after the event. These differences are due to the beaches' different morphodynamic behaviours. Whereas Faro is a reflective beach, with dominant plunging breakers, La Barrosa is mainly dissipative, having spilling breakers. The difference in beach slope and grain size could also be important in determining their response to storm events. El objetivo del presente trabajo es comparar la respuesta, ante un mismo episodio de tormenta (enero de 1996), de dos playas mesomareales de comportamiento distinto (Praia de Faro, de 10 km de longitud en el Algarve, y La Barrosa, de 8 km de longitud en Cádiz) pero pertenecientes a la misma unidad fisiográfica (el golfo de Cádiz). Para esta comparación se han estudiado una serie de levantamientos topográficos que incluyen un total de diez líneas de perfilamiento, cinco en cada área de estudio. Ambas playas se localizan en costas arenosas, expuestas, mesomareales y con una orientación similar. Sin embargo, el tiempo de respuesta es diferente en cada caso. Praia de Faro mostró una erosión total de 130 000 m³ debida a temporales y una recuperación completa tras un único ciclo mareal. La Barrosa presentó una pérdida total de arena de 80 000 m³ asociada a los temporales, con una recuperación final de 60 000 m³ después de 4 a 6 meses de los temporales. Estas diferencias son debidas al desigual comportamiento morfodinámico mostrado por ambas playas. Así, mientras Praia de Faro es una playa reflectiva con rotura dominante de tipo plunging, La Barrosa es predominantemente disipativa y con una rotura de tipo spilling. Del mismo modo, las diferencias en la pendiente y el tamaño de grano pueden ser también importantes a la hora de explicar la respuesta de ambas playas ante la llegada de temporales. Instituto Español de Oceanografía