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This article examines the discursive approach adopted by Radio Nikosia, highlighting its crucial role in the recovery of people diagnosed with severe mental illness. It examines how putting social representations aside has enabled Radio Nikosia to render agency to these social actors, acknowledging their capacity to construct, reconstruct and change their own identities. The geographic scope of the study comprises the Autonomous Community of Catalonia while the methodology followed is qualitative in nature, analysing programme audio and transcription, reports, academic articles, theses, and a participant interview. The aim of the analysis is to examine the significance of discursive practices in Radio Nikosia in modifying the permanence of identities anchored in severe mental illness. The results illustrate the practical use of radio as a powerful tool that both promotes social inclusion and impacts mental illness identity.

Resumen En este artículo analizamos Nocturno de Chile (2000), del novelista chileno Roberto Bolaño (1953-2003), a partir de la forma visual de la narración. La extensa producción de este escritor posee un carácter imagético innegable que abordaremos a partir de su correlato con las formas de producción del teatro y el cine. La hipótesis es que el diálogo inter-artes nos ofrece una nueva forma de acercamiento a su obra y, especialmente, a la novela que abordaremos en este estudio. Las imágenes de Nocturno de Chile transitan entre el fin de la democracia y la dictadura por medio del delirio de un hombre agónico que revisa su vida afectivo-literaria como respuesta a una agresión intelectual. Abstract We analyse, in this article, Nocturno de Chile (2000), by the Chilean novelist Roberto Bolaño (1953-2003), on the basis of the visual form of the story. The extensive production of this writer has an undeniable imagery-centred character that we address from its correlation with the production forms of the theater and the cinema. The hypothesis is that the inter-arts dialogue offers us a new way of approaching his work and, especially, the novel that we address in this study. The images in Nocturno de Chile circulate between the end of democracy and the dictatorship of Pinochet through the delirium of a dying man who reviews his emotional literary life in response to an intellectual attack.

Desde una perspectiva pragmática y del desarrollo teórico de la metáfora como constituyentes de la realidad, las interacciones y las acciones comunicativas, el objetivo de este artículo es identificar el efecto de las estrategias argumentativas en la deconstrucción de la identidad del trastorno mental de personas diagnosticadas con un trastorno mental. El corpus de estudio está formado por materiales de dominio público de Radio Nikosia, y está compuesto por un conjunto de textos extraídos de varias fuentes de producción discursiva en las que se han inferido las metáforas conceptuales observando su correspondencia con el dominio destino. Los resultados han mostrado que el/la hablante organiza estrategias para desenmascarar los procesos de dominación que históricamente han influido en el discurso hegemónico de la psiquiatría. Así mismo, destaca estrategias discursivas en las que las personas participantes se autorepresentan ubicándose en el rol de enfermo/a mental. El estudio de la metáfora conceptual hizo posible mostrar su influencia en los procesos argumentativos y, en concreto, la emergencia de un discurso disidente que lucha contra el estigma social del trastorno mental. From a pragmatic perspective and from the theoretical development of metaphor as constituents of reality, interactions and communicative actions, the objective of this article is to identify the effect of argumentative strategies in the deconstruction of identity in mental disorders. of people diagnosed with a mental disorder. The study corpus is made up of public domain materials from Radio Ni-kosia, and is made up of a set of texts extracted from various sources of discursive production in which conceptual metaphors have been inferred by observing their correspondence with the target domain. The results have shown that the speaker organizes strategies to unmask the domination processes that have historically influenced the hegemonic discourse of psychiatry. Likewise, it highlights discursive strategies in which the participants represent themselves by placing themselves in the role of mentally ill person. The study of conceptual metaphor made it possible to show its influence on argumentative processes and, specifically, the emergence of a dissident discourse that fights against the social stigma of mental disorders.

The ecology of benthic diatoms is scarce in diatom reviews, and it seems that the loss of interest in their local ecology (populations–communities) coincides with an increase in metacommunity studies. We include a review of the latter to highlight some unresolved issues. We aim to demonstrate the relevance of local population–community ecology for a better understanding of the metacommunity by addressing gaps such as the relevance of biotic relationships. We analyzed 132 assemblages of benthic diatoms from two neighboring catchments, with varying altitudes, lentic and lotic waters and substrates. Population–community features (e.g., populations’ relative abundance and alpha diversity) and metacommunity descriptors (e.g., beta diversity indices) were related to likely control factors such as space, catchment features, local physico-chemistry and biotic environment. Our results confirm the relevant role of local interactions between diatoms and with the biotic environment as the mechanism in assembly communities. Moreover, abiotic habitat stability enhances alternative assemblages, which are the base of the metacommunity structure, mostly by taxa sorting and mass effects. Our results suggest that in order to better disclose factors controlling metacommunities, we must study their communities at local scales where mechanisms that explain their assemblage occur, as this is the bridge to a better understanding of benthic diatom ecology.

We contribute to the knowledge of charophyte meadows as key components of aquatic systems by analysing how they affect wetland sediments. We performed a factorial-design experiment with limnocorrals (outdoor mesocosms) in a Mediterranean protected wetland with presence or absence of charophytes [Chara vulgaris (CV) and Chara hispida (CH), planted from cultures or recruited in situ from germination of their fructifications]. The first 1 cm-surficial and 2 cm-bottom sediment layers were analysed for cladoceran ephippia, ostracods valves, benthic community of bacteria and periphytic biofilm, and charophyte fructifications. In the surficial sediment, the ephippia density was fourfold higher in the conditions with charophytes than in sites with no-charophytes and higher apparent viability was found. The surficial sediment periphyton biofilm was composed mainly of diatoms, with tenfold higher biomass underneath charophytes, and a much diverse community. The specific microhabitat generated by each charophyte species was reflected in the different abundances and relationships between the analysed components, firstly establishing a divergence with the sediment without meadows and, secondly, a distinction between the meadows of CH and CV that exhibit particular morphology-architecture, might exudate different metabolites and might have different allelopathic capacities over microalgae and microinvertebrates. Thus, the charophyte–sediment tandem is relevant for biodiversity and habitat conservation.

The metacommunity concept provides a theoretical framework that aims at explaining organism distributions by a combination of environmental filtering, dispersal, and drift. However, few works have attempted a multitaxon approach and even fewer have compared two distant biogeographical regions using the same methodology. We tested the expectation that temperate (mediterranean-climate) pond metacommunities would be more influenced by environmental and spatial processes than tropical ones, because of stronger environmental gradients and a greater isolation of waterbodies. However, the pattern should be different among groups of organisms depending on their dispersal abilities. We surveyed 30 tropical and 32 mediterranean temporary ponds from Costa Rica and Spain, respectively, and obtained data on 49 environmental variables. We characterized the biological communities of bacteria and archaea (from the water column and the sediments), phytoplankton, zooplankton, benthic invertebrates, amphibians and birds, and estimated the relative role of space and environment on metacommunity organization for each group and region, by means of variation partitioning using generalized additive models. Purely environmental effects were important in both tropical and mediterranean ponds, but stronger in the latter, probably due to their larger limnological heterogeneity. Spatially correlated environment and pure spatial effects were greater in the tropics, related to higher climatic heterogeneity and dispersal processes (e.g., restriction, surplus) acting at different scales. The variability between taxonomic groups in the contribution of spatial and environmental factors to metacommunity variation was very wide, but higher in active, compared with passive, dispersers. Higher environmental effects were observed in mediterranean passive dispersers, and higher spatial effects in tropical passive dispersers. The unexplained variation was larger in the tropical setting, suggesting a higher role for stochastic processes, unmeasured environmental factors, or biotic interactions in the tropics, although this difference affected some actively dispersing groups (insects and birds) more than passive dispersers. These results, despite our limitations in comparing only two regions, provide support, for a wide variety of aquatic organisms, for the classic view of stronger abiotic niche constraints in temperate areas compared with the tropics. The heterogeneous response of taxonomic groups between regions also points to a stronger influence of regional context than organism adaptations on metacommunity organization.

Constructed wetlands (CWs) are created to enhance wildlife and improve water quality. These services are especially relevant when the CWs are linked to a natural wetland. The CWs effectiveness in improving water quality has been demonstrated, but their role in enhancing the plankton biodiversity discharged into the wetland has not. To assess this, we analysed the plankton community of three structurally different CWs created within a protected Mediterranean wetland (Albufera de València Natural Park) over two years (2014–2015). We hypothesize that alpha-diversity in the inlet communities (a species mix from anthropically disturbed environments) will be higher than those from inner and outlet sites where natural assembly processes occur, and the beta-diversity of the Natural Park will increase due to the different communities found within and between the CWs. The first hypothesis was only partially supported: in two CWs the diversity decreased due to the loss of chlorophytes and cyanobacteria, or the dominance of large copepods or cladocerans. However, when organisms in the inlet bloomed, the emerging assemblages within the CW increased the diversity, as occurred in the third CW. The species of the resulting communities were indicative of improved water quality. The second hypothesis was also proved: the CWs contributed to beta-diversity as they functioned as generators of communities. Within the CWs, vegetation and sediment supplied benthic species to the water column. Communities being discharged into the wetland were much more dissimilar than those arriving in the CWs. Therefore, the wetland assemblage beta-diversity increased thanks to the diversity of CWs.

The decrease of the water level in Mediterranean wetlands due to global warming allows UVR to reach the sediment microbial community. Macrophyte meadows, through their structure and compounds contribution, exert influence on this community. Our goal was to establish how the sediment microbial community of a wetland is harmed by UVR, and how the macrophytes mitigate such effects. We performed a field factorial experiment (UVR and macrophytes as factors) in a Mediterranean wetland. The abundance and composition of the sediment microbial community (bacteria, Archaea, microalgae and cyanobacteria) and sediment stoichiometry in superficial and sub-superficial layers were analysed. The microbial community was altered even by the small doses of UVR of the Mediterranean coastal wetlands by decreasing the periphyton abundance, including bacteria involved in C and N metabolism. Submerged macrophytes favoured the periphytic biofilm and increased sub-superficial carbon and nitrogen amounts, by promoting bacteria involved in their cycles. The shade exerted by the meadows minimized the UVR effects, driving to a community similar to that of the UVR-filtered environment. Therefore, macrophytes, through different mechanisms, can mitigate the harmful effects of UVR in sediment communities. Thus, the conservation of macrophyte meadows in highly vulnerable wetlands becomes crucial in a global change context.

Shallow freshwater ecosystems are structurally complex with different, highly-coupled habitats: the pelagic, the within-macrophyte-meadow, and the benthic. Submerged macrophyte meadows support benthic microorganisms and provide the trophic network with non-trophic relationships. Multi-interaction network analysis disentangles how these systems respond to changes in global-change-related factors. We examined whether (i) populations’ responses to such disturbances are habitat-dependent, and (ii) if whole-community configurations are different. We performed an indoor-mesocosm experiment (“control” plus two disturbed scenarios: enhanced ultraviolet radiation (UVR) or temperature), recreating shallow freshwater ecosystems. We assessed the population-nodes’ carbon biomass, their resistance and resilience to the disturbances, and global- and node-scale structural parameters of the multi-interaction network. Under the UVR-scenario, the phytoplankton C-biomass (from pelagic and within-meadow habitats) was significantly the highest, with mixotrophs dominating. Warming favoured macrophyte growth and significantly increased the network’s size and nestedness, with zooplanktonic herbivores playing a connector role. The within-meadow and benthic habitats’ nodes were highly influential for the network, whatever the scenario. The benthic nodes were the most resistant to the disturbances. Therefore, a phytoplankton- and a macrophyte-dominated configuration was attained under UVR and warming scenarios, respectively. The macrophyte meadows, and the community linked to them, were pivotal in the achievement of these contrasting configurations.

Community assembly (CA) is a topic of growing interest in ecology due to global change, among other reasons. A review of the latter 20 years in plankton CA studies suggests some advancements and drawbacks. Most works deal with groups of same trophic level species and overlook food webs, except the proposal of the PEG model. Phytoplankton has focused the most on theoretical grounds of CA: (i) to find species associations and establish their templates (condition and resource matrices) in order to define assembly rules, (ii) to set the main assembling mechanisms arising from mean-trait studies and environmental constraints, and (iii) to debate on the predictable ability of that view. After the last decade of advancements, CA future will certainly foster not only by considering classical ecological mechanisms (abiotic selection, biotic interactions, history), but also by including evolutionary and metacommunity (i.e. regional) processes. Massive DNA metabarcoding of taxa, incorporation of novel traits (such as the proportional growth rate), consideration of non-dominant species and experimentation on templates and trajectories will certainly tune up and widen our view of CA, a topic very earlier tackled successfully by Colin Reynolds.

Since the number of studies on the phytoplankton of Serranía de Cuenca (central Spain) has been scarce, this is an attempt to increase our knowledge by describing the physico-chemistry, phytoplankton flora and biomass of seven stagnant environments in summer. They are located in a karstic depopulated area where abandonment of crops and livestock has resulted in decreasing human impacts. As a result, flagellate-rich taxa indicating clean waters are dominant, showing some rare species as well. Biomass is low and seemingly limited by phosphorus. These environments are worth of wider and detailed studies on its algal flora, which will probably result in the description of novel phytoplankton taxa and new records of rare species. Dado que el número de estudios sobre el fitoplancton de la Serranía de Cuenca ha sido muy reducido hasta la fecha, esta nota describe las condiciones físico-químicas, la flora fitoplanctónica y su biovolumen estival en siete de sus ambientes estancados, enclavados en un territorio calizo donde la despoblación y el subsiguiente abandono de la agricultura y la ganadería han reducido mucho el impacto humano. Como consecuencia, se trata de especies indicadoras de aguas muy limpias, ricas en organismos flagelados, y que incluyen algunos taxones raros. El biovolumen es escaso y está aparentemente controlado por el fósforo. Estos ecosistemas son merecedores de estudios más amplios y detallados sobre su flora algológica, que probablemente den lugar a la descripción de nuevos taxones y de nuevas citas de especies poco frecuentes.

The network approach is crucial to understand how ecosystems are structured and how they will respond to the disturbances (e.g. the current global change). We have recreated the multi‐interaction network of a shallow freshwater lake dominated by submerged macrophytes (Charophytes), a known system very vulnerable to environmental changes, considering both trophic and non‐trophic relationships among its elements. To minimize the environmental variability, we established it in an experimental mesocosm, including three habitats: the pelagic, the habitat around the meadow and the periphytic community living on macrophytes. We aimed to study the structure of this network and the roles of its elements, as well as the response of this system to a foreseeable decrease in charophytes due to the global change. Thus, we tested whether there are species in the system that, due to the connections they establish, have central or connecting roles and if the reduction of charophytes affects more the elements that live intimately associated with them. Our results confirm that charophytes are the most central node in the network and that the high‐mobility large planktonic herbivores living within the meadow are acting as bridges between the conformant compartments. This suggests a structurally crucial tandem macrophytes‐herbivores with the former playing a foundation role (i.e. basal and abundant species centralizing non‐trophic interactions) and the latter being connectors in this network. Interestingly, we found that the periphytic elements where those with the highest capacity to affect the other elements of the network when being disturbed. Furthermore, an eventual decrease in the abundance of charophytes will cause a major direct damage to the meadow and periphyton, compartments to which they provide refuge and life support, respectively. Our study highlights the need of approaches encompassing the complex structure of the ecological networks to identify crucial species (such as foundation or connecting species) for their topology and vulnerability geared towards conservation biology.

The metacommunity concept provides a theoretical framework that aims at explaining organism distributions by a combination of environmental filtering, dispersal and drift. With the development of statistical tools to quantify and partially isolate the role of each of these processes, empirical metacommunity studies have multiplied worldwide. However, few works attempt a multi-taxon approach and even fewer compare two distant biogeographical regions using the same methodology. Under this framework, we tested the expectation that temperate (mediterranean-climate) pond metacommunities would be more influenced by environmental and spatial processes than tropical ones, because of stronger environmental gradients and greater isolation of waterbodies.We surveyed 30 tropical and 32 mediterranean temporary ponds from Costa Rica and Spain, respectively, and obtained data on 49 environmental variables (including limnological, hydrogeomorphological, biotic, climatic, and landscape variables). We characterized the biological communities of Bacteria and Archaea (from both the water column and the sediments), phytoplankton, zooplankton, benthic invertebrates, amphibians and birds, and estimated the relative role of space and environment on metacommunity organization for each group and region, by means of variation partitioning using Generalized Additive Models (GAMs).Environmental selection was important in both tropical and mediterranean ponds, but markedly stronger in the latter, probably due to their larger limnological heterogeneity. Spatialized environment and pure spatial effects were greater in the tropics, related to higher climatic heterogeneity and dispersal processes (e.g. restriction, surplus) acting at different scales. The variability between taxonomic groups in spatial and environmental contributions was very wide. Effects on passive and active dispersers were similar within regions but different across regions, with higher environmental effects in mediterranean active dispersers. The residual (unexplained) variation was larger in tropical pond metacommunities, suggesting a higher role for stochastic processes and/or effects of biotic interactions in the tropics. Overall, these results provide support, for a wide variety of organisms related to aquatic habitats, for the classical view of stronger abiotic niche constraints in temperate areas compared to the tropics.

[EN] The past twenty years have witnessed a rise in the analysis of long-term limnological data given the need to know whether global warming is affecting freshwaters, and if so, how. Previous studies indicated that processes affecting ecosystem function-ing may develop slowly, thus requiring long-term study, as in the case of the eutrophication-oligotrophication gradient. Here we report annual averages and seasonal variability of meteorological data (air temperature, solar radiation, rainfall) and the main limnological variables (lake level, water temperature, euphotic depth, mixing depth, nitrogen and phosphorus compounds and phytoplankton biomass) for a gravel-pit, seepage lake close to Madrid (Central Spain), collected monthly from 1992 to 2018. Linear trends (both upward and downward), long-term constancy, regime shifts, piecewise patterns and mixed patterns (constant and piecewise) were found for the variables tested, but their variability did not increase over time. Water warming and decreased lake levels were related with atmospheric warming. In turn, these physical changes covaried with nitrate increase and decreases in total phosphorus and phytoplankton biomass. However, the weak relationships between climate- and limnological variables (for example, the lack of rainfall effects on lake level) would indicate that other factors, such as land use, were more influential. Broadly speaking, it would appear that the observed limnological patterns were greatly influenced by the local increase in novel lake basins through mining activities, which led to a decrease in lake level until the year 2000, and the ecological stabilization of a recently created ecosystem, which is an analogous process to that occurring after reservoir construction. The above processes might have partly offset global warming effects in this lake but twenty years is ALMOST nothing within the framework of this fascinating puzzle. Hence longer studies are necessary to gain an accurate picture of gravel-pit limnology, which is urgently needed., [ES] El análisis de series largas de datos en Limnología ha aumentado en la última década debido a la necesidad de saber si el calentamiento global está afectando a nuestros ecosistemas de agua dulce y cómo. Antes, ya se había demostrado que los procesos relevantes para el funcionamiento del ecosistema podían ser lentos y requerían estudios a largo plazo, como ocurrió con el gradiente eutrofización-oligotrofización. En este trabajo se presentan los promedios anuales y la variabilidad estacional de las principales variables meteorológicas (temperatura atmosférica, radiación solar, precipitación) y limnológicas (nivel del lago, temperatura del agua, capa fótica, capa de mezcla, concentraciones de nitrógeno y fósforo y biomasa fitoplanctónica) de una laguna de gravera próxima a Madrid (centro de España), alimentada por aguas subterráneas. Los datos se obtuvieron mensualmente desde 1992 hasta 2018. En esas variables, detectamos tendencias lineales (crecientes y decrecientes), constancia a largo plazo, cambios de régimen, pautas “en sierra” y pautas mixtas (constancia en un periodo y dinámica “en sierra” en otros); además, no parece que aumenten su variabilidad estacional con el tiempo. También se observó cómo el calentamiento del aire estaba vinculado con el calentamiento y la pérdida de nivel del agua. A su vez, esos cambios físicos en la laguna covariaban con un aumento del nitrato y con la pérdida de fósforo y de biomasa fitoplanctónica. Sin embargo, la debilidad de las relaciones entre las variables ligadas al clima y las limnológicas (por ejemplo, la falta de efecto de las lluvias sobre el nivel del agua de la laguna) apunta a que otros factores, como el uso del territorio, tuvieran también relevancia. Grosso modo, parece que la creación local de nuevas cubetas lacustres por la actividad minera, que hizo descender notablemente el nivel lacustre hacia el año 2000, y la estabilización ecológica de un ecosistema de creación reciente, proceso análogo al que sucede tras la creación de un embalse, pudieron ser determinantes para las pautas limnológicas observadas. Dichos procesos probablemente hayan contrarrestado los previsibles efectos del calentamiento global. Por lo tanto, veinte años no parecen CASI nada para montar este interesante rompecabezas cuya imagen final nos urgiría conocer, aunque ello haría necesario prolongar los estudios.

Zooplankton abundance and composition is sensitive to eutrophication, and its top-down effect in the planktonic food web can alter the classification of the trophic state of waterbodies based on th...

The effects of the combined roles of abiotic and biotic factors defining foodweb structure are often ignored. In aquatic systems, abiotic variables can regulate food webs through bottom-up ...

Global change effects, such as warming and increases in nitrogen loading, alter vulnerable Mediterranean aquatic systems, and charophytes can be one of the most affected groups. We addressed the possible interaction between these factors on two populations of the cosmopolitan charophytes Chara hispida and Chara vulgaris. Populations were taken from two different environments, a nitrate-poor mountain lake and a nitrate-rich Mediterranean coastal spring. The laboratory experiment had a 2 × 2 factorial design based on two nitrate levels (similar to and double the local conditions) and two temperatures. Increased temperatures favoured the growth of the four populations, but an increase in nitrate did not have any effect on their growth or architecture. Both species took up and stored more nitrogen (measured as %N in plant tissue) when more nitrate was supplied, and warming favoured this increase in %N and, consequently, in N:P ratio. The effects of both factors depended on the local conditions where the populations originated and on the species. Chara vulgaris, a pioneer species, exhibited more phenotypic plasticity than C. hispida, and its ecotype from the coastal spring was better adapted to changes in temperature and nitrate level. These differential responses to warming conditions and nitrate pollution may modify charophyte diversity, which might be reflected in ecosystem performance, a matter of concern in vulnerable Mediterranean water bodies where these species co-occur., This study was supported by the Spanish Ministry of Economy and Competitiveness for research project CGL2014-54502-C2-1-P (including EC FEDER funding). Eric Puche is the holder of a grant (UV-INV-PREDOC16F1-383810) funded by the University of Valencia.

Based on our results, we propose the use of zooplankton abundance (density or biomass) as an indicator to complement the information currently being used concerning the quality of water in reservoirs. Until now, the Water Framework Directive (EU) for lakes and reservoirs has not included zooplankton because the classification of the water trophic state is based on a bottom-up model: an increase in nutrients implies an increase in primary producers and, therefore, poorer water quality. The use of zooplankton has recently been claimed due to their sensitivity to environmental changes and their control over primary producers. From our work, carried out from 2006 to 2009 (summer and winter seasons) in 20 reservoirs found in various Mediterranean river basins, we prove the relationship of the abundance of zooplankton with the trophic state. Zooplankton abundance, with or without interaction with other agents, explained much of the distribution of total phosphorus in the reservoirs, thus relating the trophic status with the aquatic food chain. In addition, we have found, illustrated by the zooplankton: phytoplankton ratio, how the top-down control masked high production situations in the system. Zooplankton's ability to cover up these cases of poor water quality highlight that the indicators presently being used are frequently insufficient.

Evaluating how environmental stressor interactions influence ecosystem structure and functioning is critical to understanding the response of ecosystems to global change. We exposed a species-poor planktonic community to P pulses in the absence and presence of solar ultraviolet radiation (UVR). We used a field-mesocosm study in an oligotrophic mid-altitude lake to test the hypothesis that interaction between these factors affects the community’s diversity and composition, but not its biomass-size spectrum, making this community resilient in terms of its C-transfer function. Our findings show that P pulses and UVR affected the relative abundance of different planktonic populations. The abundance of phytoplankton was enhanced strongly by P pulses and secondarily by UVR. The UVR × P interaction affected only the smallest autotrophic species. Chlorococcal abundance increased, whereas chroococcal cyanobacteria decreased. However, UVR had a much more pronounced effect than P on the composition of microc...

Currently a debate exists about whether the reduced growth of macrophytes with increased nitrogen loading in shallow ecosystems is determined by ecological or physiological factors. To discover whe...

An increase in temperature of approximately 4 °C is expected to occur in the Mediterranean by the end of the century. Concomitant to this warming, a foreseeable rise in salinity will affect aquatic species. We addressed the effects of warming and salinity, and their interaction on three coexisting characean species (Chara aspera, C. hispida and C. vulgaris) from a Spanish Mediterranean interdunal pond (spring water temperature 20–23 °C, when charophytes re-grew; salinity 1.3–1.8 PSU). A laboratory experiment was designed with two levels of water temperature treatment (23 and 27 °C), plus two levels of salinity treatment (0.4 and 4.0 PSU). The variables considered were total length, number of ramifications and nodes, dry weight, growth rate and stoichiometric composition. Three clear response patterns arose: (i) C. aspera growth was favoured by the 4 °C rise in temperature and the 10-fold increase in salinity when considered separately, but no synergy occurred when these factors interacted; (ii) C. hispida growth did not change with the temperature, but was negatively affected by the salinity increase, and (iii) C. vulgaris growth was enhanced by the temperature, a fact that compensated for the damaging effect of increased salinity. Variations of N and P concentrations with treatments were similar in C. aspera and C. vulgaris. We demonstrate how charophyte response to the interaction of increased temperature and salinity is species-specific and different under isolated stressors. Therefore, this study highlights how simultaneous drivers of global change might affect the composition of charophyte meadows in Mediterranean shallow wetlands.

[EN] Theoretical Limnology is a neglected topic nowadays. Here we make an endeavour to launch and promote theoretical developments in Limnology, dealing with the mechanistic relationships among biogeochemistry, production, species richness and food webs in the most common-sized lakes, i.e. small-to-medium ones. Although few studies are currently underway to support includes such relationships, well-known interactions enable us to place such lakes within a conceptual model bottom-up model, which include water retention, total phosphorus and dissolved organic carbon as the driving variables. All response variables are viewed on the basis of area, which enables circumventing the otherwise important issue of depth (and hence stratification). Seven lake types are considered with unique sets of features concerning species richness, food web connectance, nutrient fluxes and lake metabolism. The extension and tuning of this conceptual model to all stagnant waters (from small to large) can be undertaken when more data on these topics are available, probably taking horizontal transport features into account. We look forward to seeing future developments in theoretical Limnology, also paying special attention to Mediterranean limnological features which differ somewhat from those of cold temperate-and tropical areas., [ES] La Limnología teórica es un tema olvidado en estos tiempos. Por eso, aquí proponemos un intento modesto de iniciar y promover teorías limnológicas, explorando las relaciones mecanicistas entre biogeoquímica, producción, riqueza específica y redes tróficas para los tipos más frecuentes de tamaño de lago, que son los pequeños y medianos. Aunque el número de estudios que ofrece resultados para apoyar dichas relaciones es bastante reducido, algunas bien conocidas de estas facilitan el organizar los lagos dentro de un esquema conceptual que usa la retención del agua, el fósforo total y el carbono orgánico disuelto como variables de control. Considerar todas las variables de respuesta por unidad de superficie permitirá pasar por alto el importante asunto de la profundidad, y el de la estratificación térmica por lo tanto. Nuestro esquema conceptual vislumbra siete tipos de lagos con conjuntos de respuestas únicas relativas a la riqueza de especies, la conectancia de las redes tróficas, los flujos biogeoquímicos y la productividad lacustre. Una mayor concreción de este modelo conceptual y la extensión del mismo a todos los ambientes estancados (de los pequeños a los grandes) podrán llevarse a cabo cuando haya más datos sobre estos temas, probablemente teniendo en cuenta además alguna variable relativa al transporte horizontal. Tras esta contribución, nos gustaría ver nuevos desarrollos teóricos que –además– presten atención a la Limnología mediterránea, la cual difiere un poco de la existente en las zonas templadas frías y tropicales del globo.

In recent years, little scrutiny has been devoted to charophytes with regard to carbon, nitrogen and phosphorus contents, their ratios and the factors controlling them. Data from published literature, and our own unpublished data, will be used along with environmental data to depict overall statistical distributions and controlling factors of charophyte stoichiometry, along with two hypotheses already suggested for plankton. Data on whole and decarbonated plants will be reviewed separately, but the role of the phosphorus-bound, external crust in the charophyte metabolism is still unclear. These algae have an intermediate carbon content, and lower nitrogen and phosphorus contents, among other aquatic plants. Hence their C:N and C:P ratios are usually higher than those of other submerged plants. Phosphorus is the outstanding key factor for charophyte growth and stoichiometry. Charophyte P content appears to be related to C, N and P sedimentary contents; a higher P content will result in increased growth rates. The maximal growth rates recorded occur at charophyte C:N:P ratios of 343-759:18-44:1, higher than the well-known Redfield values for optimal growth in other algae. While PAR irradiance partly controlled charophyte nitrogen content and the C:N ratio, UV-B radiation increased C and N content, albeit not affecting nutrient ratios. We conclude that the light:nutrient and the growth rate hypotheses hold true for charophytes. Increasing temperatures by global warming could decrease charophyte P content, thereby augmenting the C:P ratio. Further studies on charophyte stoichiometry are encouraged, specifically to disentangle the relationship between plant and carbonate crust and the role of stonewort stoichiometry in aquatic system.

Faced with an environment of accelerated change, the long-term dynamics of biotic communities can be approached to build a consistent and causal picture of the communities’ life. We have undertaken a 25-year monthly-sampling study on the phytoplankton of a meso-oligotrophic lake, paying attention to controlling factors of overall biomass (TB) and taxonomical group biomass (TGBs). Long-term series included decreased trends of TB and TGBs, and multi-scale periodicity. A decadal TB periodicity emerged related to nitrogen concentration and Cryptophytes. Annual periodicities were mainly related to air and water temperature controlling the abundance of Chlorophytes or Dinoflagellates. Intra-annual cycles could arise from autogenic processes. The analysis by periods revealed relevant dynamics (for example, Diatom periodicities), hidden in the analysis of the complete series. These results allow us to establish that: i) two organizational levels of phytoplankton change differently in time scales from months to decades; ii) controlling factors (climate, water physics and chemistry) act at different time scales and on different TGBs, and iii) different combinations of the “taxonomical group-control factor-trend and periodicity” set throughout the studied time explain total biomass dynamics. A holistic approach (multiple complementary analyses) is necessary to disentangle the different actors and relationships that explain non-stationary long-term phytoplankton dynamics.

Estuaries are coastal wetlands that deserve special attention because they are vulnerable, biodiversity- and service-rich environments. However, estuaries of tropical areas have been scarcely studied regarding water quality and biodiversity in spite of strong developments of their agricultural and livestock sectors. Two estuaries on the Pacific Nicaragua in which snapper cages had been set up were studied regarding water physicochemical properties, microalgae and cyanobacteria along with their dynamics over a hydrological year. Both environments showed excellent water quality (oligotrophy and absence of harmful organisms) arising from their fluvial features. During the rainy season, there was a decline in chemical compounds and microorganisms. In the dry period nutrients and salinity promoted different assemblages of microscopic primary producers that were never too dense. Nutrient inputs from shrimp farms, agricultural crops and snapper cages did not appear to increase eutrophication and cyanobacterial blooms did not occur. Furthermore, the strong fluvial character of these estuaries seems to prevent the entry of harmful dinoflagellates from marine areas.

Ecosystems are complex and multivariate; hence, methods to assess the dynamics of ecosystems should have the capacity to evaluate multiple indicators simultaneously. Most research on identifying leading indicators of regime shifts has focused on univariate methods and simple models which have limited utility when evaluating real ecosystems, particularly because drivers are often unknown. We discuss some common univariate and multivariate approaches for detecting critical transitions in ecosystems and demonstrate their capabilities via case studies. Synthesis and applications. We illustrate the utility of an information theory-based index for assessing ecosystem dynamics. Trends in this index also provide a sentinel of both abrupt and gradual transitions in ecosystems.

Increases in ultraviolet radiation (UVR), a negative global change factor, affect aquatic primary producers. This effect is expected to be modulated by other global change factors, and to be different for populations adapted to different environments. A common garden experimental approach using freshwater green macroalgae, the cosmopolitan charophyte species Chara hispida and C. vulgaris, allowed us to test whether the beneficial increases in water temperature (T) and nitrate concentration (N) mitigate negative UVR effects. Also, whether these interactions would be not only species-specific but also according to the origin of the population; therefore, two populations of each species were used: one from a coastal wetland and the other from a mountain lake. Two factorial-design experiments were performed: (i) the presence and absence of UVR × lower and higher T × four populations, and (ii) the presence and absence of UVR × lower and higher N × four populations. Response variables were: growth, morphometry, UVR-protective compounds, photosynthetic pigments, and stoichiometric composition. There were consistent response patterns in the key variables that represent different organization levels. Our main results showed that both warming and, to a lesser extent, the increase in nutrients ameliorated the negative effects of UVR on the molecular processes involved in acclimation to UVR, and that such a mitigating effect depended on the different phenotypic plasticity of each species and each ecotype. The coastal populations, being from a more variable environment, were more resilient than the mountain populations, mainly because of changes in growth and morphology.

Research has dealt with coupling of chemical element cycles and feedback in recent years. Sometimes, this biogeochemical coupling is reversed through abiotic or biotic (including man-made) processes. It is then called biogeochemical decoupling and is a disconnection between two chemical elements whereby transformations of one affect cycling of the other, and results in asynchronical behavior of chemical elements. It appears to be more important and widespread than earlier reports suggest, and gives rise to important changes in element stoichiometry of resources. These changes in turn modify organismal stoichiometry that, if great enough, can affect biodiversity and food webs, thus altering community structure and function. Biogeochemical decoupling then impinges on ecosystem dynamics and may impair ecosystem services.

Neste trabalho, será analisado o teatro dissidente argentino do período ditatorial até os dias atuais. Esta resposta artística beligerante aos modelos políticos sociais autoritários está determinada pelos diferentes contextos e pelas duas vertentes nas quais atua: micropolítica, que busca criar um lugar alternativo, e micropolítica, que aspira ser macropolítica (Dubatti. Cartografía teatral).

It takes approximately 14 yr to produce a new rice (Oryza sativa L.) variety, that is, from initial hybridization to its commercial release. Currently, new varieties are identified based on morphological descriptors, which have been efficient over time. However, due to the main constraints on seed type impose to other breeding objectives and the pressure of continuous release of varieties, high degree of parentage, and genetic and morphological uniformity has been observed in the breeding populations. The objectives of this study were: to determine the genetic variability of Chilean and foreign commercial rice varieties, and determine, identify, and certify the genetic relationships among varieties, using simple sequence repeat (SSR) markers. A total of 16 commercial varieties, some of them closely related, were included in the study, which were genetically analyzed using 54 microsatellites. The 54 microsatellite loci allowed the discrimination among the 16 varieties. The number of alleles ranged between 2 and 8 with a mean of 3.54 alleles per locus, while the polymorphism information content (PIC) presented a mean of 0.44. The genetic distance and diversity parameters between pairs of varieties indicate a limited diversity among these genotypes. The cluster analysis indicated that varieties were grouped according to their grain type and pedigree. Results demonstrate that the identification and certification of varieties using microsatellite markers could be a good complement to existing agro-morphological data when varieties are closed related.