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Global warming and direct anthropogenic impacts, such as water extraction, are largely affecting water budgets in Mediterranean wetlands, thereby increasing wetland salinities and isolation, and decreasing water depths and hydroperiods (duration of the inundation period). These wetland features are key elements structuring waterbird communities. However, the ultimate and net consequences of these dynamic conditions on waterbird assemblages are largely unknown. We combined a regular sampling on waterbird presence through the 2008 annual cycle with in-situ data on these relevant environmental predictors of waterbird distribution to model habitat selection for 69 individual species in a typical Mediterranean wetland network in south-western Spain. Species association with environmental features were subsequently used to predict changes in habitat suitability for each species under three climate change scenarios (encompassing changes in environment that ranged from 10% to 50% change as predicted by climatic models). Waterbirds distributed themselves unevenly throughout environmental gradients and water salinity was the most important gradient structuring the distribution of the community. Environmental suitability for the guilds of diving birds and vegetation gleaners will be reduced according to future climate scenarios, while most small wading birds will benefit from changing conditions. Resident species and those that breed in this wetland network will be also more impacted than those using this area for wintering or stopover. We provide here a tool that can be used in a horizon-scanning framework to identify emerging issues on waterbird conservation and to anticipate suitable management actions : Datasets as supporting information to article “How will climate change affect endangered Mediterranean waterbirds?” to be published in PLOS ONE. Address questions to Francisco Ramírez: ramirez@ub.edu

Integrated multitrophic aquaculture (IMTA) is a versatile technology emerging as an ecological and sustainable solution for traditional monoculture aquacultures in terms of effluent treatment. Nevertheless, IMTA is still poorly applied in aquaculture industry due to, among other reasons, the lack of effective, low-investment and low-maintenance solutions. In this study, one has developed a practical and low maintenance IMTA-pilot system, settled in a semi-intensive coastal aquaculture. The optimisation and performance of the system was validated using Ulva spp., a macroalgae that naturally grows in the fishponds of the local aquaculture. Several cultivation experiments were performed at lab-scale and in the IMTA-pilot system, in static mode. The specific growth rate (SGR), yield, nutrient removal, N and C enrichment, protein and pigment content were monitored. Ulva spp. successfully thrived in effluent from the fish species sea bream (Sparus aurata) and sea bass (Dicentrarchus labrax) production tanks and significantly reduced inorganic nutrient load in the effluent, particularly, NH4+, PO43− and NO3−. The enrichment of nitrogen in Ulva spp.’s tissues indicated nitrogen assimilation by the algae, though, the cultivated Ulva spp. showed lower amounts of protein and pigments in comparison to the wild type. This study indicates that the designed IMTA-pilot system is an efficient solution for fish effluent treatment and Ulva spp., a suitable effluent remediator.

Abstract Accurate knowledge of tidal turbine impacts on the far-field hydrodynamic conditions, which extend from 3 to 20 diameters downstream the turbine, is essential for the estimation of tidal resource, farm layout design and environmental impact. For this purpose, tidal turbine operation is modelled within coastal models, as enhanced bottom friction, or momentum sinks. In Delft3D-FLOW, a state-of-the-art coastal model, turbine operation is usually represented via momentum losses, using the Porous Plate tool. However, the Porous Plate tool presents significant limitations to accurately represent energy extraction and geometry of tidal turbines. Recently, a new tool (Actuator Disc) based on the Momentum Actuator Disc Theory (MADT) was developed in Delft3D-FLOW, overcoming the aforementioned limitations and showing excellent results against laboratory data. The aim of this work is to compare the behaviour of the Actuator Disc and Porous Plate on the far-field hydrodynamics. Overall, significant differences were found, with the Porous Plate significantly underestimating the impact on instantaneous and residual flow velocities and turbulence conditions, when the turbine operates at its rated power. Consequently, MADT appears as the best alternative to investigate the far-field hydrodynamic impacts of tidal turbine operation and previous research based on the Porous Plate tool should be revisited.

The social confinement resulting from the COVID-19 crisis temporarily reduced greenhouse gas emissions. Although experts contend that the decrease in pollution rates was not drastic, some surveys detect growth in social concern about the climate. In this new climate-conscious environment, municipalities and local governments are promoting a new way of living and caring for cities, even before they can regain national and international freedom of movement. This work analyzes the connections between new climate awareness arising from the COVID-19 crisis, proposals of sustainable citizenship around the world, and its communication on Twitter to educate the new eco-conscious audience. The methodology mixes quantitative and qualitative analysis, using the Twitonomy Premium tool and the Twitter research tool with data extracted at the end of December 2020. Among the top ten most influential and active accounts, the results show educational institutions, local institutions, companies, neighborhoods, associations, and influencers. The impossibility of living in the city has not prevented citizen education and commitment to make real change for when that city and its citizens return to normality. However, this new normality must be different: more ecological, more responsible, more sustainable, and practiced from early childhood.

Artículos en revistas It is shown how a standard nonlinear programming approach can be applied to solve a sophisticated version of the static optimal mix problem in generation planning. The model presented includes technical minima of thermal capacity, detailed operating models of storage-hydro and pumped-hydro units, a realistic model of capital costs for hydro plants, operating reserve and minimum demand constraints, and capacity already in existence. The model formulation is in a format that can be directly handled by the well-known MINOS code and can be efficiently solved. The use of a general-purpose nonlinear optimization program results in a great flexibility, making it possible to modify the model formulation easily or to adapt it to the characteristics of a particular electric system. A realistic application to the Spanish generation system is presented info:eu-repo/semantics/publishedVersion

Abstract. An improved understanding of present-day climate variability and change relies on high-quality data sets from the past 2 millennia. Global efforts to model regional climate modes are in the process of being validated against, and integrated with, records of past vegetation change. For South America, however, the full potential of vegetation records for evaluating and improving climate models has hitherto not been sufficiently acknowledged due to an absence of information on the spatial and temporal coverage of study sites. This paper therefore serves as a guide to high-quality pollen records that capture environmental variability during the last 2 millennia. We identify 60 vegetation (pollen) records from across South America which satisfy geochronological requirements set out for climate modelling, and we discuss their sensitivity to the spatial signature of climate modes throughout the continent. Diverse patterns of vegetation response to climate change are observed, with more similar patterns of change in the lowlands and varying intensity and direction of responses in the highlands. Pollen records display local-scale responses to climate modes; thus, it is necessary to understand how vegetation–climate interactions might diverge under variable settings. We provide a qualitative translation from pollen metrics to climate variables. Additionally, pollen is an excellent indicator of human impact through time. We discuss evidence for human land use in pollen records and provide an overview considered useful for archaeological hypothesis testing and important in distinguishing natural from anthropogenically driven vegetation change. We stress the need for the palynological community to be more familiar with climate variability patterns to correctly attribute the potential causes of observed vegetation dynamics. This manuscript forms part of the wider LOng-Term multi-proxy climate REconstructions and Dynamics in South America – 2k initiative that provides the ideal framework for the integration of the various palaeoclimatic subdisciplines and palaeo-science, thereby jump-starting and fostering multidisciplinary research into environmental change on centennial and millennial timescales.