Winter MVC

Winter MVC és un framework de presentació basat en Spring MVC que simplifica la metodologia de configuracions.

Impacts on the deep-sea ecosystem by a severe coastal storm

Major coastal storms, associated with strong winds, high waves and intensified currents, and occasionally with heavy rains and flash floods, are mostly known because of the serious damage they can cause along the shoreline and the threats they pose to navigation. However, there is a profound lack of knowledge on the deep-sea impacts of severe coastal storms. Concurrent measurements of key parameters along the coast and in the deep-sea are extremely rare. Here we present a unique data set showing how one of the most extreme coastal storms of the last decades lashing the Western Mediterranean Sea rapidly impacted the deep-sea ecosystem. The storm peaked the 26th of December 2008 leading to the remobilization of a shallow-water reservoir of marine organic carbon associated with fine particles and resulting in its redistribution across the deep basin. The storm also initiated the movement of large amounts of coarse shelf sediment, which abraded and buried benthic communities. Our findings demonstrate, first, that severe coastal storms are highly efficient in transporting organic carbon from shallow water to deep water, thus contributing to its sequestration and, second, that natural, intermittent atmospheric drivers sensitive to global climate change have the potential to tremendously impact the largest and least known ecosystem on Earth, the deep-sea ecosystem.

Impacts on the deep-sea ecosystem by a severe coastal storm

Major coastal storms, associated with strong winds, high waves and intensified currents, and occasionally with heavy rains and flash floods, are mostly known because of the serious damage they can cause along the shoreline and the threats they pose to navigation. However, there is a profound lack of knowledge on the deep-sea impacts of severe coastal storms. Concurrent measurements of key parameters along the coast and in the deep-sea are extremely rare. Here we present a unique data set showing how one of the most extreme coastal storms of the last decades lashing the Western Mediterranean Sea rapidly impacted the deep-sea ecosystem. The storm peaked the 26th of December 2008 leading to the remobilization of a shallow-water reservoir of marine organic carbon associated with fine particles and resulting in its redistribution across the deep basin. The storm also initiated the movement of large amounts of coarse shelf sediment, which abraded and buried benthic communities. Our findings demonstrate, first, that severe coastal storms are highly efficient in transporting organic carbon from shallow water to deep water, thus contributing to its sequestration and, second, that natural, intermittent atmospheric drivers sensitive to global climate change have the potential to tremendously impact the largest and least known ecosystem on Earth, the deep-sea ecosystem.

Modeling storm events to investigate the influence of the stream¿catchment interface zone on stream biogeochemistry

We formulate a new mixing model to explore hydrological and chemical conditions under which the interface between the stream and catchment interface (SCI) influences the release of reactive solutes into stream water during storms. Physically, the SCI corresponds to the hyporheic/riparian sediments. In the new model this interface is coupled through a bidirectional water exchange to the conventional two components mixing model. Simulations show that the influence of the SCI on stream solute dynamics during storms is detectable when the runoff event is dominated by the infiltrated groundwater component that flows through the SCI before entering the stream and when the flux of solutes released from SCI sediments is similar to, or higher than, the solute flux carried by the groundwater. Dissolved organic carbon (DOC) and nitrate data from two small Mediterranean streams obtained during storms are compared to results from simulations using the new model to discern the circumstances under which the SCI is likely to control the dynamics of reactive solutes in streams. The simulations and the comparisons with empirical data suggest that the new mixing model may be especially appropriate for streams in which the periodic, or persistent, abrupt changes in the level of riparian groundwater exert hydrologic control on flux of biologically reactive fluxes between the riparian/hyporheic compartment and the stream water.

Cultural control of herbicide-resistant Lolium rigidum Gaud. populations in winter cereal in Northeastern Spain

Lolium rigidum Gaud. is one of the most common weed species in winter cereals in Northeastern Spain. Herbicide resistance has been growing since the mid 90's and exclusive herbicide use is not enough in many cases, so that it is necessary to combine as many control tools as possible. Six field trials have been conducted during the cropping seasons 2001-02, 2002-03 and 2003-04 on winter cereal infested with herbicide resistant L. rigidum in Northeastern Spain testing different cultural control strategies. Sowing delay was conducted at five fields, mouldboard ploughing at four fields, the combination of sowing delay and ploughing at two fields, increasing the cereal sowing density and combined with sowing delay at one field. Sowing delay was confirmed to have an irregular efficacy depending on the L. rigidum emergence during the delay period. In the trials, weed emergence was reduced up to 88% in the best case but there was no effect in two cases. Ploughing had a more constant efficacy and reduced weed emergence between 50 and 80% although stoniness impeded in one occasion a correct soil inversion causing a very low efficacy. Increasing the cereal sowing rate did not reduce the weed population. The combination of the different methods did not increase significantly the individual efficacy, and one method was clearly more effective than the other, depending on the trial. In fields with high L. rigidum density, these methods are not effective enough and need to be combined with other methods, which are discussed in the text.

Survival of wild adults of Ceratitis capitata (Wiedemann) under natural winter conditions in north east Spain

The overwintering of the Mediterranean fruit fly (medfly), Ceratitis capitata (Wiedemann) at the northern limits of its geographic distribution is not yet well known. With the aim of estimating the survival rate of medfly adults in northeast Spain under natural winter conditions, a two-winter-season trial was carried out. A control was carried out in a climatic chamber at 25°C. The results showed that medfly adults were unable to survive the entire winter season in the Girona area. Climatic conditions, including the daily minimum temperature, daily maximum temperature and the high rainfall, appeared to be involved in adult mortality in winter.

Evidence for the influence of the North Atlantic Oscillation on the total ozone column at northern low latitudes and midlatitudes during winter and summer seasons.

The strong influence of the winter North Atlantic Oscillation (NAO) on the total ozone column (TOC) in the Northern Hemisphere has been reported in a number of previous studies. In this study we show that this influence is not restricted to the winter season but is also significant in summer. Especially interesting effects of the summer NAO (SNAO) on the TOC are observed over the eastern Mediterranean region, where a strongly positive SNAO index is related to the creation of a geopotential height-negative anomaly over Greece with maximum amplitude at 200 hPa. Another anomaly was observed west of the Iberian Peninsula with similar effects on the TOC. Analyzing 26 years of Total Ozone Mapping Spectrometer (TOMS) and Ozone Monitoring Instrument (OMI) data from the equator to midlatitudes (60°) in the Northern Hemisphere, we demonstrate that the SNAO accounts for up to 30% of the TOC variability with a strong latitudinal and longitudinal dependence. Additionally, we obtain significant correlations between the NAO index and the thermal tropopause pressure and also with the geopotential heights at 200 and 500 hPa. Finally, some indirect connections between NAO and the TOC through teleconnections are also discussed.

The snow storm of the 8th of March 2010 in Barcelona: a paradigmatic case

A heavy precipitation event swept over Catalonia (NE Spain) on 8 March 2010, with a total amount that ex- ceeded 100mm locally and snowfall of more than 60cm near the coast. Unusual for this region and at this time of the year, this snowfall event affected mainly the coastal region and was accompanied by thunderstorms and strong wind gusts in some areas. Most of the damage was due to"wet snow", a kind of snow that favours accretion on power lines and causes line-breaking and subsequent interruption of the electricity supply. This paper conducts an interdisciplinary analysis of the event to show its great societal impact and the role played by the recently developed social networks (it has been called the first"Snowfall 2.0"), as well to analyse the meteorologi- cal factors associated with the major damage, and to propose an indicator that could summarise them. With this aim, the paper introduces the event and its societal impact and com- pares it with other important snowfalls that have affected the Catalan coast, using the PRESSGAMA database. The sec- ond part of the paper shows the event"s main meteorological features and analyses the near-surface atmospheric variables responsible for the major damage through the application of the SAFRAN (Système d"analyse fournissant des renseigne- ments atmosphériques à la neige) mesoscale analysis, which, together with the proposed"wind, wet-snow index" (WWSI), allows to estimate the severity of the event. This snow storm provides further evidence of our vulnerability to natural haz- ards and highlights the importance of a multidisciplinary ap- proach in analysing societal impact and the meteorological factors responsible for this kind of event.

The Mediterranean benthic herbivores show diverse responses to extreme storm disturbances

Catastrophic storms have been observed to be one of the major elements in shaping the standing structure of marine benthic ecosystems. Yet, little is known about the effect of catastrophic storms on ecosystem processes. Specifically, herbivory is the main control mechanism of macrophyte communities in the Mediterranean, with two main key herbivores: the sea urchin Paracentrotus lividus and the fish Sarpa salpa. Consequently, the effects of extreme storm events on these two herbivores (at the population level and on their behaviour) may be critical for the functioning of the ecosystem. With the aim of filling this gap, we took advantage of two parallel studies that were conducted before, during and after an unexpected catastrophic storm event. Specifically, fish and sea urchin abundance were assessed before and after the storm in monitored fixed areas (one site for sea urchin assessment and 3 sites for fish visual transects). Additionally, we investigated the behavioural response to the disturbance of S. salpa fishes that had been tagged with acoustic transmitters. Given their low mobility, sea urchins were severely affected by the storm (ca. 50% losses) with higher losses in those patches with a higher density of sea urchins. This may be due to a limited availability of refuges within each patch. In contrast, fish abundance was not affected, as fish were able to move to protected areas (i.e. deeper) as a result of the high mobility of this species. Our results highlight that catastrophic storms differentially affect the two dominant macroherbivores of rocky macroalgal and seagrass systems due to differences in mobility and escaping strategies. This study emphasises that under catastrophic disturbances, the presence of different responses among the key herbivores of the system may be critical for the maintenance of the herbivory function.

Braving the Storm: How Are Global Biofuel Policies Sustained Despite Being Contested? An Analysis of the Biofuel Discourses of the EU, Brazil and Mozambique

Considered as a remedy to multiple problems that our world is facing, biofuels are nowadays promoted on a global scale. Despite this globalised approach, however, biofuels are heavily contested. Not only the social implications of biofuels are disputed and uncertain, particularly in countries of the global South, but also their environmental and economic rationales. Given these huge controversies, policies promoting biofuels would seem difficult to maintain. Yet, support for them has been surprisingly well established on the political agendas. With the aim of understanding this puzzle, this study asks how the dominant approach to biofuels has been sustained on a global level. In order to answer this question, the meanings and assumptions in biofuel discourses are explored through the lens of Maarten Hajer’s “argumentative” discourse analysis. Based on the existence of a “partnership for sustainable bioenergy” between the EU, Brazil and Mozambique, the study takes these three locations as case studies. The analysis reveals that various discursive strategies, including a particular problem construction and the use of two main story-lines, have played an important role in ensuring the permanence of the global approach to biofuels. Moreover, while the discourse of critics against biofuels demonstrates that there is room for contestation, the analysis finds that the opponents’ discourse largely fails to target the most salient justification for biofuels. A more effective strategy for critics would therefore be to also question the problem constructions underpinning this main justification in the global discourse.

Foliar photochemical processes and carbon metabolism under favourable and adverse winter conditions in a Mediterranean mixed forest, Catalonia (Spain)

Evergreen trees in the Mediterranean region must cope with a wide range of environmental stresses from summer drought to winter cold. The mildness of Mediterranean winters can periodically lead to favourable environmental conditions above the threshold for a positive carbon balance, benefitting evergreen woody species more than deciduous ones. The comparatively lower solar energy input in winter decreases the foliar light saturation point. This leads to a higher susceptibility to photoinhibitory stress especially when chilly (< 12 C) or freezing temperatures (< 0 C) coincide with clear skies and relatively high solar irradiances. Nonetheless, the advantage of evergreen species that are able to photosynthesize all year round where a significant fraction can be attributed to winter months, compensates for the lower carbon uptake during spring and summer in comparison to deciduous species. We investigated the ecophysiological behaviour of three co-occurring mature evergreen tree species (Quercus ilex L., Pinus halepensis Mill., and Arbutus unedo L.). Therefore, we collected twigs from the field during a period of mild winter conditions and after a sudden cold period. After both periods, the state of the photosynthetic machinery was tested in the laboratory by estimating the foliar photosynthetic potential with CO2 response curves in parallel with chlorophyll fluorescence measurements. The studied evergreen tree species benefited strongly from mild winter conditions by exhibiting extraordinarily high photosynthetic potentials. A sudden period of frost, however, negatively affected the photosynthetic apparatus, leading to significant decreases in key physiological parameters such as the maximum carboxylation velocity (Vc,max), the maximum photosynthetic electron transport rate (Jmax), and the optimal fluorometric quantum yield of photosystem II (Fv/Fm). The responses of Vc,max and Jmax were highly species specific, with Q. ilex exhibiting the highest and P. halepensis the lowest reductions. In contrast, the optimal fluorometric quantum yield of photosystem II (Fv/Fm) was significantly lower in A. unedo after the cold period. The leaf position played an important role in Q. ilex showing a stronger winter effect on sunlit leaves in comparison to shaded leaves. Our results generally agreed with the previous classifications of photoinhibition-tolerant (P. halepensis) and photoinhibitionavoiding (Q. ilex) species on the basis of their susceptibility to dynamic photoinhibition, whereas A. unedo was the least tolerant to photoinhibition, which was chronic in this species. Q. ilex and P. halepensis seem to follow contrasting photoprotective strategies. However, they seemed equally successful under the prevailing conditions exhibiting an adaptive advantage over A. unedo. These results show that our understanding of the dynamics of interspecific competition in Mediterranean ecosystems requires consideration of the physiological behaviour during winter which may have important implications for long-term carbon budgets and growth trends.