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Abstract Iberian barbel (Luciobarbus bocagei Steindachner, 1864) and Iberian nase (Pseudochondrostoma polylepis Steindachner, 1864) are two Mediterranean potamodromous fish species known to perform annual upstream migrations to reach spring spawning grounds. In the Mondego River basin, at the Coimbra dam, migratory movement patterns and individual size structure were assessed through a video recording monitoring system installed on an upstream section of a vertical-slot fish pass. Visual census for these target species during two consecutive annual cycles (2013–2014) revealed alternative migratory patterns, with the first peak of upstream movements in autumn, for both barbel (October–November) and nase (November–December). Circadian movements of both species showed a diurnal preference, contrary to what is usually described for these species. Size structure analysis for individuals of both species showed significant intra-annual differences in the size of migrating fish. Boosted regression trees models applied to the 2013–2014 visual count data identified flow and temperature as the most influential environmental predictors, triggering both species’ movements in each direction in the study years. These results provide novel information on the timing of the migratory movements of these potamodromous fish, which can be used to adapt current management and conservation measures to the specificities of their migratory behaviour.

Abstract Current climate projections for mid-latitude regions globally indicate an intensification of wind-driven coastal upwelling due to warming conditions. The dynamics of mid-latitude coastal upwelling are marked by environmental variability across temporal scales, which affect key physiological processes in marine calcifying organisms and can impact their large-scale distribution patterns. In this context, marine invertebrates often exhibit phenotypic plasticity, enabling them to adapt to environmental change. In this study, we examined the physiological performance (i.e., metabolism, Thermal Performance Curves, and biomass and calcification rates) of individuals of the intertidal mollusk Chiton granosus, a chiton found from northern Peru to Cape Horn (5° to 55°S). Our spatial study design indicated a pattern of contrasting conditions among locations. The Talcaruca site, characterized by persistent upwelling and serving as a biogeographic break, exhibited lower pH and carbonate saturation states, along with higher pCO2, compared to the sites located to the north and south of this location (Huasco and Los Molles, respectively). In agreement with the spatial pattern in carbonate system parameters, long-term temperature records showed lower temperatures that changed faster over synoptic scales (1–15 days) at Talcaruca, in contrast to the more stable conditions at the sites outside the break. Physiological performance traits from individuals from the Talcaruca population exhibited higher values and more significant variability, along with significantly broader and greater warming tolerance than chitons from the Huasco and Los Molles populations. Moreover, marked changes in local abundance patterns over three years suggested population-level responses to the challenging environmental conditions at the biogeographic break. Thus, C. granosus from the Talcaruca upwelling zone represents a local population with wide tolerance ranges that may be capable of withstanding future upwelling intensification on the Southern Eastern Pacific coast and likely serving as a source of propagules for less adapted populations.

Abstract The seascape comprises multiple environmental variables that interact with species biology to determine patterns of spatial genetic variation. The environment imposes spatially variable selective forces together with homogenizing and diverging drivers that facilitate or restrict dispersal, which is a complex, time-dependent process. Understanding how the seascape influences spatial patterns of genetic variation remains elusive, particularly in coastal upwelling systems. Here, we combine genome-wide SNP data, Lagrangian larval dispersal simulated over a hydrodynamic model, and ocean environmental information to quantify the relative contribution of ocean circulation and environmental heterogeneity as drivers of the spatial genetic structure of two congeneric intertidal limpets, Scurria scurra and S. araucana, along the central coast of Chile. We find that a genetic break observed in both limpet species coincides with a break in connectivity shown by the Lagrangian dispersal, suggesting that mean ocean circulation is an important seascape feature, in particular for S. scurra. For S. araucana, environmental variation appears as a better predictor of genetic structure than ocean circulation. Overall, our study shows broad patterns of seascape forcing on genetic diversity and contributes to our understanding of the complex ecological and evolutionary interactions along coastal upwelling systems.

Turbidity is associated with the loss of water transparency due to the presence of particles, sediments, suspended solids, and organic or inorganic compounds in the water, of natural or anthropogenic origin. Our study aimed to evaluate the spatio-temporal variability of turbidity from Sentinel-2 (S2) images in the Reloncaví sound and fjord, in Northern Patagonia, Chile, a coastal ecosystem that is intensively used by finfish and shellfish aquaculture. To this end, we downloaded 123 S2 images and assembled a five-year time series (2016–2020) covering five study sites (R1 to R5) located along the axis of the fjord and seaward into the sound. We used Acolite to perform the atmospheric correction and estimate turbidity with two algorithms proposed by Nechad et al. (2009, 2016 Nv09 and Nv16, respectively). When compared to match-up, and in situ measurements, both algorithms had the same performance (R2 = 0.40). The Nv09 algorithm, however, yielded smaller errors than Nv16 (RMSE = 0.66 FNU and RMSE = 0.84 FNU, respectively). Results from true-color imagery and two Nechad algorithms singled an image from the austral autumn of 2019 as the one with the highest turbidity. Similarly, three images from the 2020 austral autumn (May 20, 25, 30) also exhibited high turbidity values. The turbid plumes with the greatest extent occurred in the autumn of 2019 and 2020, coinciding with the most severe storms and runoff events of the year, and the highest turbidity values. Temporal trends in turbidity were not significant at any of the study sites. However, turbidity trends at sites R1 and R2 suggested an increasing trend, while the other sites showed the opposite trend. Site R1 recorded the highest turbidity values, and the lowest values were recorded at R5 in the center of the sound. The month of May was characterized by the highest turbidity values. The application of algorithms from high-resolution satellite images proved to be effective for the estimation and mapping of this water quality parameter in the study area. The use of S2 imagery unraveled a predictable spatial and temporal structure of turbidity patterns in this optically complex aquatic environment. Our results suggest that the availability of in situ data and the continued evaluation of the performance of the Nechad algorithms can yield significant insights into the dynamics and impacts of turbid waters in this important coastal ecosystem.

There is growing evidence that studying aquatic acoustic communities can provide ecologically relevant information. Understanding these communities may offer unique insights into species behaviour and ecology, while consolidating passive acoustic monitoring as a tool for mapping the presence of target species or estimating changes in aquatic biodiversity. Fish can be significant soundscape contributors, but most soniferous fish species are yet to be identified. Here, we crossed information of three key fish acoustic communities in the Lusitanian Province of the Temperate Northern Atlantic (the Madeira archipelago, the Azores archipelago and Arrábida in mainland Portugal) to unveil potential sources of unidentified fish sounds. We found that the three communities shared various sound types and we were able to narrow down the list of possible fish sound sources. Several sound types were suggested to be produced by species of the Pomacentridae, Scorpaenidae and Serranidae families. We also observed that the sound type /kwa/, associated with Scorpaena spp., exhibited more variations in the geographic area where more species of this genus are known to be present. This study showcases that, as databases of unidentified fish sounds continue to grow, future comparisons of multiple acoustic communities may provide insights into unknown fish sound sources and sound types.

ABSTRACT The limited temporal completeness and taxonomic accuracy of species lists, made available in a traditional manner in scientific publications, has always represented a problem. These lists are invariably limited to a few taxonomic groups and do not represent up-to-date knowledge of all species and classifications. In this context, the Brazilian megadiverse fauna is no exception, and the Catálogo Taxonômico da Fauna do Brasil (CTFB) (http://fauna.jbrj.gov.br/), made public in 2015, represents a database on biodiversity anchored on a list of valid and expertly recognized scientific names of animals in Brazil. The CTFB is updated in near real time by a team of more than 800 specialists. By January 1, 2024, the CTFB compiled 133,691 nominal species, with 125,138 that were considered valid. Most of the valid species were arthropods (82.3%, with more than 102,000 species) and chordates (7.69%, with over 11,000 species). These taxa were followed by a cluster composed of Mollusca (3,567 species), Platyhelminthes (2,292 species), Annelida (1,833 species), and Nematoda (1,447 species). All remaining groups had less than 1,000 species reported in Brazil, with Cnidaria (831 species), Porifera (628 species), Rotifera (606 species), and Bryozoa (520 species) representing those with more than 500 species. Analysis of the CTFB database can facilitate and direct efforts towards the discovery of new species in Brazil, but it is also fundamental in providing the best available list of valid nominal species to users, including those in science, health, conservation efforts, and any initiative involving animals. The importance of the CTFB is evidenced by the elevated number of citations in the scientific literature in diverse areas of biology, law, anthropology, education, forensic science, and veterinary science, among others.

Abstract Worldwide climate‐driven shifts in the distribution of species is of special concern when it involves habitat‐forming species. In the coastal environment, large Laminarian algae—kelps—form key coastal ecosystems that support complex and diverse food webs. Among kelps, Macrocystis pyrifera is the most widely distributed habitat‐forming species and provides essential ecosystem services. This study aimed to establish the main drivers of future distributional changes on a global scale and use them to predict future habitat suitability. Using species distribution models (SDM), we examined the changes in global distribution of M. pyrifera under different emission scenarios with a focus on the Southeast Pacific shores. To constrain the drivers of our simulations to the most important factors controlling kelp forest distribution across spatial scales, we explored a suite of environmental variables and validated the predictions derived from the SDMs. Minimum sea surface temperature was the single most important variable explaining the global distribution of suitable habitat for M. pyrifera. Under different climate change scenarios, we always observed a decrease of suitable habitat at low latitudes, while an increase was detected in other regions, mostly at high latitudes. Along the Southeast Pacific, we observed an upper range contraction of −17.08° S of latitude for 2090–2100 under the RCP8.5 scenario, implying a loss of habitat suitability throughout the coast of Peru and poleward to −27.83° S in Chile. Along the area of Northern Chile where a complete habitat loss is predicted by our model, natural stands are under heavy exploitation. The loss of habitat suitability will take place worldwide: Significant impacts on marine biodiversity and ecosystem functioning are likely. Furthermore, changes in habitat suitability are a harbinger of massive impacts in the socio‐ecological systems of the Southeast Pacific.

Abstract Sea lamprey Petromyzon marinus is an anadromous and semelparous fish without homing behaviors. Despite being a freshwater, free‐living organism for a large part of their life cycle, its adulthood is spent as a parasite of marine vertebrates. In their native European range, while it is well‐established that sea lampreys comprise a single nearly‐panmictic population, few studies have further explored the evolutionary history of natural populations. Here, we performed the first genome‐wide characterization of sea lamprey's genetic diversity in their European natural range. The objectives were to investigate the connectivity among river basins and explore evolutionary processes mediating dispersal during the marine phase, with the sequencing of 186 individuals from 8 locations spanning the North Eastern Atlantic coast and the North Sea with double‐digest RAD‐sequencing, obtaining a total of 30,910 bi‐allelic SNPs. Population genetic analyses reinforced the existence of a single metapopulation encompassing freshwater spawning sites within the North Eastern Atlantic and the North Sea, though the prevalence of private alleles at northern latitudes suggested some limits to the species' dispersal. Seascape genomics suggested a scenario where oxygen concentration and river runoffs impose spatially varying selection across their distribution range. Exploring associations with the abundance of potential hosts further suggested that hake and cod could also impose selective pressures, although the nature of such putative biotic interactions was unresolved. Overall, the identification of adaptive seascapes in a panmictic anadromous species could contribute to conservation practices by providing information for restoration activities to mitigate local extinctions on freshwater sites.

In this work, a conductive ink based on microfibrillated cellulose (MFC) and multiwalled carbon nanotubes (MWCNTs) was used to produce transducers for rapid liquid identification. The transducers are simple resistive devices that can be easily fabricated by scalable printing techniques. We monitored the electrical response due to the interaction between a given liquid with the carbon nanotube–cellulose film over time. Using principal component analysis of the electrical response, we were able to extract robust data to differentiate between the liquids. We show that the proposed liquid sensor can classify different liquids, including organic solvents (acetone, chloroform, and different alcohols) and is also able to differentiate low concentrations of glycerin in water (10–100 ppm). We have also investigated the influence of two important properties of the liquids, namely dielectric constant and vapor pressure, on the transduction of the MFC-MWCNT sensors. These results were corroborated by independent heat flow measurements (thermogravimetric analysis). The proposed MFC-MWCNT sensor platform may help paving the way to rapid, inexpensive, and robust liquid analysis and identification.

Industrial applications of nanomaterials require large-scale production methods, such as liquid phase exfoliation (LPE). Regarding this, it is imperative to characterize the obtained materials to tailor parameters such as exfoliation medium, duration, and mechanical energy source to the desired applications. This work presents results of statistical analyses of talc flakes obtained by LPE in four different media. Talc is a phyllosilicate that can be exfoliated into nanoflakes with great mechanical properties. Sodium cholate at two different concentrations (below and at the critical micelar concentration), butanone, and Triton-X100 were employed as exfoliation medium for talc. Using recent published statistical analysis methods based on atomic force microscopy images of thousands of flakes, the shape and size distribution of nanotalc obtained using the four different media are compared. This comparison highlights the strengths and weaknesses of the media tested and hopefully will facilitate the choice of the medium for applications that have specific requirements.

During June 2022, Spain was one of the countries most affected worldwide by a multicountry monkeypox outbreak with chains of transmission without identified links to disease-endemic countries. We provide epidemiologic features of cases reported in Spain and the coordinated measures taken to respond to this outbreak.

Coastal societies have lived at the seaward edge of the Atacama Desert since at least 12,000 years ago. Kelp forest ecosystems provide evidence for important subsistence activity along the entire Chilean coast through fishing and gathering. Despite their importance, especially in hyperarid contexts with limited plant abundance, there is scarce evidence of kelp in archaeological contexts, hampering the study of kelp use in the past. In the present study, we use the presence of small marine invertebrates, inhabitants of stipes and holdfasts of macroalgae, as proxies that indicate past kelp presence. We analyze samples of three species of snails (Tegula atra, Tegula tridentata, and Diloma nigerrima) and one limpet (Scurria scurra) from nine archaeological sites dated between 7,000 and 500 cal years before present located around the area of Taltal (25°Lat S). Modern samples of these species were collected to reconstruct the size of fragmented archaeological shells and subsequently estimate the size of harvested kelps. Through this approach, we estimated the size and relative abundance of kelp used by coastal groups that inhabited the southern part of the Atacama Desert for around 6,500 years. Our results are a contribution to the scarce information on the presence and use of kelp in the prehistory of the Americas and contribute to comparative perspectives with other areas of the world where the use of kelp by humans in the past has already been explored.

Abstract The production of 2D material flakes in large quantities is a rapidly evolving field and a cornerstone for their industrial applicability. Although flake production has advanced in a fast pace, its statistical characterization is somewhat slower, with few examples in the literature which may lack either modelling uniformity and/or physical equivalence to actual flake dimensions. The present work brings a methodology for 2D material flake characterization with a threefold target: (i) propose a set of morphological shape parameters that correctly map to actual and relevant flake dimensions; (ii) find a single distribution function that efficiently describes all these parameter distributions; and (iii) suggest a representation system—topological vectors—that uniquely characterizes the statistical flake morphology within a given distribution. The applicability of such methodology is illustrated via the analysis of tens of thousands flakes of graphene/graphite and talc, which were submitted to different production protocols. The richness of information unveiled by this universal methodology may help the development of necessary standardization procedures for the imminent 2D-materials industry.

Abstract Background Three-axis acceleration sensor acoustic transmitters (AccelTag) programmed to identify specific acceleration patterns associated with particular behaviours (e.g., burrowing, attack) were used to study some aspects of the ecology of the Lusitanian toadfish Halobatrachus didactylus (Bloch & Schneider 1801). The AccelTag combines the features of archival tags (records acceleration in all three directions measuring also roll-independent pitch/tilt angle and roll around the fish’s axis) and acoustic transmitters. Therefore, this tag can autonomously identify and record specific signatures (i.e., behaviour patterns) of different movements transmitting autonomously and periodically the data to an acoustic biotelemetry receiver. Lusitanian toadfish is a subtropical marine teleost confined to estuaries in its northern limit of distribution due to thermal constraints. During 2010 (August and October), 24 toadfish were captured, tagged with the AccelTag and released in the Mira estuary, SW coast of Portugal, where an array of underwater automatic acoustic biotelemetry receivers was deployed. Results Around 40% of AccelTag transmissions from tagged fish that stayed in the study area were logged by the acoustic receiver array. The Lusitanian toadfish exhibited low activity during late summer and early autumn (

Ecological stability depends on interactions between different levels of biological organization. The insurance effects occur when increasing species diversity leads to more temporally invariable (i.e., more stable) community-level properties, due in part to asynchronous population-level fluctuations. While the study of insurance effects has received considerable attention, the role of dominant species that contribute with particular functional traits across different level of organizations is less understood. Using a field-based manipulative experiment, we investigated how species richness and different types of parameters at the population level, such as the invariability of dominants, population invariability, and population asynchrony, influence the community invariability. The experiment involved the repetitive removal of the canopy forming alga Mazzaella laminarioides (hereafter “Mazzaella”) during 32 months in two rocky intertidal sites of northern-central Chile. We predicted that the invariability of dominants enhances community invariability, that the effect of multispecies population-level parameters on community invariability are dependent on species richness, and that subdominant algae are unable to fully compensate the loss of canopies of the dominant species. Biomass of algae and mobile invertebrates was quantified over time. We observed independent effects of Mazzaella removal and community-wide asynchrony on community invariability. While canopy removal reduced community invariability, population asynchrony boosted community invariability regardless of the presence of canopies. In addition, filamentous and foliose algae were unable to compensate the loss of biomass triggered by the experimental removal of Mazzaella. Canopy removal led to a severe decrement in the biomass of macrograzers, while, at the same time, increased the biomass of mesograzers. Asynchrony stemmed from compensatory trophic responses of mesograzers to increased abundances of opportunistic algae. Thus, further work on consumer-resource interactions will improve our understanding of the links between population- and community-level aspects of stability.

Marine Protected Areas (MPAs) require effective indicators to assess their performance, in compliance with the goals of relevant national and international commitments. Achieving and prioritizing shortlists of multidisciplinary indicators demands a significant effort from specialists to depict the multiple conservation and socioeconomic interests, and the large complexity of natural systems. The present paper describes a structured expert-based methodology (process and outputs) to co-define a list of multidisciplinary MPA performance indicators. This work was promoted by the management authority of coastal MPAs in mainland Portugal to gather a consensual and feasible list of indicators that would guide the design of a future national monitoring program. Hence, Portuguese coastal MPAs served as a case study to develop such a process between 2019 and 2020. In the end, participants (1) agreed on a shortlist of prioritized indicators (i.e., environmental, governance, and socioeconomic indicators) and (2) defined minimum monitoring frequencies for the indicators in this list, compatible with the potential replicability of the associated survey methods. The present approach recommends that management plans incorporate monitoring procedures and survey methods, with a validated list of indicators and associated monitoring periodicity, agreed among researchers, MPA managers and governance experts. The proposed methodology, and the lessons learned from it, can support future processes aiming to define and prioritize MPA performance indicators.

Folds naturally appear on nanometrically thin materials, also called “2D materials”, after exfoliation, eventually creating folded edges across the resulting flakes. We investigate the adhesion and flexural properties of single-layered and multilayered 2D materials upon folding in the present work. This is accomplished by measuring and modeling mechanical properties of folded edges, which allows for the experimental determination of the bending stiffness (κ) of multilayered 2D materials as a function of the number of layers (n). In the case of talc, we obtain κ ∝ n3 for n ≥ 5, indicating no interlayer sliding upon folding, at least in this thickness range. In contrast, tip-enhanced Raman spectroscopy measurements on edges in folded graphene flakes, 14 layers thick, show no significant strain. This indicates that layers in graphene flakes, up to 5 nm thick, can still slip to relieve stress, showing the richness of the effect in 2D systems. The obtained interlayer adhesion energy for graphene (0.25 N/m) and talc (0.62 N/m) is in good agreement with recent experimental results and theoretical predictions. The obtained value for the adhesion energy of graphene on a silicon substrate is also in agreement with previous results.

The insertion of functional groups in polymer compounds may facilitate their interaction with different drugs. PEG polymers are widely used for their low melting point, low toxicity, drug compatibility, and hydrophilicity. They are used as pharmaceutical excipients for the formulation of conventional or modified released drugs and are designed to be upgraded as drug-modulating controllers at specific sites in the body. Indomethacin has been used in the controlled release of drugs because it is a drug that have good interaction with different polymers. The drug is a non-steroidal anti-inflammatory drug used in the treatment of rheumatoid arthritis, osteoarthritis, spondylitis, and other disorders. In this work, PEG 4000 had its chain modified by organic reactions and their derivatives were emulsified to form microparticles using polyvinyl alcohol as an emulsifier. Posteriorly were also incorporated with indomethacin. The samples were characterized to prove the influence of indomethacin on the morphology and thermal behavior of this polymer. The controlled release was performed in the time from 0 to 240 min using the Ultraviolet Spectroscopy to quantify indomethacin released from the polymer matrix for these 4 hours. Releases over the time were satisfactory as concentrations increased over time, which we can conclude that the structural modification of PEG 4000 was beneficial in the release of the indomethacin drug.

En la presente investigación se determina la influencia de los social media influencer en la decisión de compra de consumidores millennials de Arequipa-Perú, zona donde se percibe una gran aceptación de las redes sociales por parte de las nuevas generaciones. Para el desarrollo del presente estudio se aplicó un cuestionario de 54 preguntas a una muestra de 404 personas en el rango de 18 a 35 años que representan al segmento de millennials, los resultados mostraron una correlación de 0.595 positiva moderada obtenida a través del procesamiento de datos mediante el software Smart PLS en su versión 3.2.8.La investigación demostró que los social media influencer si tienen la capacidad de influir y generar una decisión de compra en los millennials de esta región, además el conocimiento de marca y la veracidad percibida del influencer son dos dimensiones que también contribuyen en la toma de decisiones de compra, en contraste el valor del contenido y la credibilidad del influencer no ayudan en la toma de decisiones de compra.

Abstract The study of sister species that occur in parapatry around biogeographic transition zones can help understand the evolutionary processes that underlie the changes in species composition across biogeographic transition zones. The South Eastern Pacific (SEP) coast is a highly productive coastal system that exhibits a broad biogeographic transition zone around 30–35°S. Here, we present a comparative genome‐wide analysis of the sister species Scurria viridula and Scurria zebrina, that occur in parapatry and whose poleward and equatorward range edges intersect in the 30–35°S SEP biogeographic transition zone. We sampled 118 specimens sourced from nine sites from Tocopilla (22°S) to Chiloé (41°S) including one site where both species overlap and analyzed over 8000 biallelic single nucleotide polymorphisms. We found evidence of hybridization between these species in the contact zone and found significant but contrasting population structures for both species. Our results indicate that the genetic structure in S. viridula, which is currently expanding its range poleward, follows a simple isolation by distance model with no traces of natural selection (no evidence of outlier loci). In contrast, S. zebrina, which has its equatorward range edge at the transition zone, displayed a pronounced genetic break approximately at 32–34°S, along a region of marked environmental heterogeneity in association with a semi‐permanent coastal upwelling regime. For S. zebrina we also found 43 outlier loci associated with this genetic break, with a significant proportion of them clustering in a single linkage group. This marked difference in the presence of outlier loci between species suggests that they could be responding differently to local environmental challenges found at their overlapping geographic range edges, thus providing important new insights about genomic changes around biogeographic transition zones in sister species and the forces that shape genetic diversity in intertidal marine species.

Spatial synchrony occurs when geographically separated time series exhibit correlated temporal variability. Studies of synchrony between different environmental variables within marine ecosystems worldwide have highlighted the extent of system responses to exogenous large-scale forcing. However, these spatial connections remain largely unstudied in marine systems, particularly complex coastlines, where a paucity of field observations precludes the analysis of time series. Here, we used time-frequency analyses based on wavelet and wavelet coherence (WC) analysis to quantify the synchrony (co-variations) between environmental time series derived from MODIS (moderate resolution imaging spectroradiometer) in the topographically complex inner sea of Chiloé (ISC, 41–44°S) for the 2003–2022 period. We find that the strength of the synchrony between chlorophyll a (Chla) and turbid river plumes (for which we use remote sensing reflectance at 645 nm, Rrs645) varies between the northern and southern areas of the ISC; higher synchrony, measured as the WC between these variables, is observed along the northern basin where water and particle exchanges with the Pacific Ocean are reduced. The WC analysis showed higher synchrony between these variables, with dominant periodicities of 0.5 and 1 year resulting from the hydrological regime of the freshwater input in the area that persisted throughout the 2004–2018 period. Our results suggest that the strong and significant spatial synchrony at the regional scale is likely related to the phases of large-scale climatic oscillations, as inferred through the partial wavelet coherence analysis. Potential mechanisms driving spatial synchrony are discussed in the context of climate and oceanographic regimes in the area.

The meagre Argyrosomus regius, one of the largest sciaenidae in the world, is a valuable resource for fisheries and aquaculture. Despite its socioeconomic relevance, knowledge about population dynamics and wild stocks is still scarce, and conservation risks are associated with overexploitation. Two genetic distinct groups, one in the North Atlantic Ocean and one in the eastern Mediterranean Sea, were identified by previous studies. However, little is known about the genetic structure of the Atlantic group, where four important spawning areas have been identified. To assess if each spawning area is an independent breeding unit, the genetic diversity, populational structure, and demographic history of A. regius along the North–East and Eastern Central Atlantic coast were analyzed, using 15 microsatellite loci. Results corroborate the hypothesis tested, suggesting four genetic groups: a first group encompassing individuals from the Gironde spawning area, a second group encompassing individuals from the Tagus spawning area, a third group corresponding to individuals captured in the Algarve region, and a forth group gathering individuals from Morocco and Mauritania. This study reveals the need for specific fisheries management plans considering genetic structure information, and highlights the need for international cooperation.

Value engineering is a methodology developed based on cost reduction and product function-ality increase and it has become a competitive factor which allows micro and small businesses owners to improve their performance. This paper proposes a method to identify some techniques of value engineering for improvement and redesigning of products, cost reduction, and component substitution. The proposed method uses the factors in value management of the micro and small businesses of the clothing textiles sector in the region of Arequipa. The results of the research provide some evidences that there is a direct positive correlation between the aforementioned techniques and value management and the results yield significant values, in all cases. A regression analysis is used in product redesigning and cost reduction.

Na medida em que avançamos no século XXI, têm ficado cada vez mais claros os contornos geopolíticos de um conflito em escala global – ao antagonizar a China, os Estados Unidos levaram alguns analistas a falar em uma segunda Guerra Fria. Neste artigo procuro demonstrar que, de fato, o deslocamento do eixo estratégico norte-americano em direção ao oceano Pacífico apresenta consideráveis paralelos com a estratégia de Contenção [Containment] empregada contra o bloco soviético. Procurei, contudo, expor as dificuldades de reedição desta estratégia por parte dos Estados Unidos diante de um adversário cuja política externa tem se mostrado cada vez mais inovadora.

Stability is a central property of complex systems and encompasses multiple dimensions such as resistance, resilience, recovery, and invariability. How these dimensions correlate among them is focus of recent ecological research, but empirical evidence at regional scales, at which conservation decisions are usually made, remains absent. Using a field-based manipulative experiment conducted in two marine intertidal regions, we analyze the correlations among different aspects of stability in functioning (community cover) and composition of local communities facing a press disturbance. The experiment involved the removal of the local space-dominant species for 35 months in eight sites under different environmental regimes in northern- and southern-central Chile (ca. 30 and 40°S, respectively). After the disturbance, the magnitude of the initial responses and the recovery patterns were similar among communities dominated by different species, but varied between the functional and compositional response variables, and among four dimensions of stability. The recovery trajectories in function and composition remained mostly uncorrelated across the system. Yet, larger initial functional responses were associated with faster recovery trajectories—high functional resilience, in turn, was associated with both, high and low variability in the pattern of recovery. Finally, the compositional stability dimensions were independent from each other. The results suggest that varying community compositions can perform similar levels of functioning, which might be the result of strong compensatory dynamics among species competing for space in these communities. Knowledge of several, and sometimes independent, aspects of stability is mandatory to fully describe the stability of complex ecological systems.

El inventario de la flora de las 59 áreas protegidas que hacen parte del sistema de Parques Nacionales Naturales (PNN) de Colombia no está completo, ya que se desconoce el número de especies y la composición de plantas que alberga. Compilamos información disponible de colecciones de herbario y literatura para establecer una lista preliminar de especies de plantas vasculares que se encuentran en los PNN. Esta lista fue confrontada con el Catálogo de plantas y líquenes de Colombia y se establecieron valores porcentuales del número de especies con respecto a las cifras nacionales. Estimamos que el inventario de la flora del sistema de PNN se encuentra en un 70 %. Lo conocido en PNN hasta el momento representa el 39.1 % de las especies de plantas vasculares conocidas para el país. El 18.2 % de las especies endémicas de Colombia y el 56 % de las especies categorizadas en algún grado de amenaza se encuentran en PNN. Planteamos el uso de estas cifras como índices de representatividad de la flora colombiana para complementar otros índices, como el de porcentaje del territorio nacional bajo conservación, y enfatizamos que los parques nacionales asociados a los Andes son los más determinantes para mejorar la representatividad de estos indicadores de la flora.

Estudiamos los musgos que crecen en el valle del río Patía, en el suroccidente colombiano, que comprende zonas de bosque muy seco tropical y bosque seco premontano. En la franja altitudinal comprendida entre 550 y 1500 m s. n. m., encontramos 75 especies de musgos (28 familias y 53 géneros), 34 de ellas acrocárpicas (11 familias y 23 géneros) y 41 pleurocárpicas (17 familias y 30 géneros). Las familias con mayor número de especies son: Bryaceae (10), Pottiaceae (9), Hypnaceae (6), Macromitriaceae (5), Brachytheciaceae (5), Entodontaceae (5), Fissidentaceae (5) y Sematophyllaceae (4). Los géneros mejor representados son Bryum (6), Fissidens (5), Sematophyllum (4) y Entodon (3). El 60 % de las especies se encuentran en un solo tipo de sustrato: suelo (31), corteza (10), materia orgánica (3) y roca (1); el 40 % restante se encuentra en 2 o más sustratos. Bosques, matorrales, taludes y corrientes de agua son los hábitats preferidos por los musgos. Los elementos dominantes son neotropicales extraandinos (35 spp.), cosmopolitas (11), ampliamente tropicales (8) y afroamericanos (5).

The influence of graphene and retinoic acid (RA) – a π-conjugated organic semiconductor – interface on their hybrid system is investigated. The physical properties of the interface are assessed via scanning probe microscopy, optical spectroscopy (photoluminescence and Raman) and ab initio calculations. The graphene/RA interaction induces the formation of a well-organized π-conjugated self-assembled monolayer (SAM) at the interface. Such structural organization leads to the high optical emission efficiency of the RA SAM, even at room temperature. Additionally, photo-assisted electrical force microscopy, photo-assisted scanning Kelvin probe microscopy and Raman spectroscopy indicate a RA-induced graphene doping and photo-charge generation. Finally, the optical excitation of the RA monolayer generates surface potential changes on the hybrid system. In summary, interface-induced organized structures atop 2D materials may have an important impact on both design and operation of π-conjugated nanomaterial-based hybrid systems.

The synthesis of two-dimensional diamond is the ultimate goal of diamond thin-film technology. Here, the authors perform Raman spectroscopy of bilayer graphene under pressure, and obtain spectroscopic evidence of formation of diamondene, an atomically thin form of diamond.

Using 19 years of remotely sensed Enhanced Vegetation Index (EVI), we examined the effects of climatic variability on terrestrial vegetation of six protected areas along southwestern South America, from the semiarid edge of the Atacama desert to southern Patagonia (30°S–51°S). The relationship between satellite phenology and climate indices, namely MEI (Multivariate ENSO Index), PDO (Pacific Decadal Oscillation) and SAM (Southern Annular Mode) were established using statistical analyses for non-stationary patterns. The annual mode of phenological activity fluctuated in strength through time from the semiarid region to the border of southern Patagonia. Concomitantly, enhanced synchrony between EVI and climatic oscillations appeared over interannual cycles. Cross correlations revealed that variability in MEI was the lead predictor of EVI fluctuations over scales shorter than 4 months at lower latitudes and for the most poleward study site. The PDO was correlated with EVI over lags longer than 4 months at low latitude sites, while the SAM showed relationships with EVI only for sites located around 40°S. Our results indicate that the long-term phenological variability of the vegetation within protected areas along southwestern South America is controlled by processes linked to climate indices and that their influence varies latitudinally. Further studies over longer time scales will be needed to improve our understanding the impacts of climate change on vegetation condition and its effect over phenological variability.

ABSTRACT The Atlantic Forest is one of the most disturbed Brazilian biomes, with 183 out of 298 species of mammals occurring in the state of Rio de Janeiro. In this study, we aimed to characterize the diversity, community structure, and habitat use of small mammals in the FIOCRUZ Atlantic Forest Campus (CFMA), including areas of Pedra Branca State Park (PBSP, subunit Pau da Fome), state of Rio de Janeiro. We also compared species diversity and composition between two moments 15 years apart (2001 and 2012-2015) and analyzed the population dynamics of the marsupial Didelphis aurita (Wied-Neuwied, 1826). Small mammal captures were made in different habitats: sylvatic-urban interface areas near human dwellings, disturbed forest, and preserved forest areas. Five marsupial species and four rodent species were captured in both periods. There was a reduction in species richness and β diversity between the two periods, indicating that disturbances in the environment over the years may have affected the small mammal community structure. The most altered environment showed the greatest species richness and abundance, while the forest areas showed the smallest values, which may be explained by the loss of mammal species, mainly specialist species in forested areas. We identified three groups of species according to habitat preferences: one related to environments with a higher density of vegetation in upper strata - Marmosa paraguayana (Tate, 1931) and Monodelphis americana (Müller, 1776), another related to a higher density in lower forest strata - Akodon cursor (Winge, 1887), and another with no association with the investigated habitat variables - D. aurita and Oligoryzomys nigripes (Olfers, 1818). The small mammal community structure showed a low level of nestedness in both sampling periods. This study is the first report to evaluate the community structure of small mammals in the sylvatic-urban interface area of Pedra Branca State Park, the largest forest reserve within an urban area in Brazil. The surveys indicate that the small mammal diversity was low in both sampling periods and in both areas, and a species loss in the Pau da Fome locality was observed, despite it is a conservation unit. The greater species abundance and richness in the most disturbed areas suggest an increase of factors favoring the occurrence of synanthropic and opportunistic species.

Over the last century, climate change has impacted the physiology, distribution, and phenology of marine and terrestrial primary producers worldwide. The study of these fluctuations has been hindered due to the complex response of plants to environmental forcing over large spatial and temporal scales. To bridge this gap, we investigated the synchrony in seasonal phenological activity between marine and terrestrial primary producers to environmental and climatic variability across northern Patagonia. We disentangled the effects on the biological activity of local processes using advanced time-frequency analysis and partial wavelet coherence on 15 years (2003−2017) of data from MODIS (Moderate Resolution Imaging Spectroradiometer) onboard the Terra and Aqua satellites and global climatic variability using large-scale climate indices. Our results show that periodic variations in both coastal ocean and land productivity are associated with sea surface temperature forcing over seasonal scales and with climatic forcing over multi-annual (2−4 years) modes. These complex relationships indicate that large-scale climatic processes primarily modulate the synchronous phenological seasonal activity across northern Patagonia, which makes these unique ecosystems highly exposed to future climatic change.

Organic–inorganic magnetic hybrid materials (MHMs) combine a nonmagnetic and a magnetic component by means of electrostatic interactions or covalent bonds, and notable features can be achieved. Herein, we describe an application of a self-assembled material based on ferrite associated with β-cyclodextrin (Fe-Ni/Zn/βCD) at the nanoscale level. This MHM and pure ferrite (Fe-Ni/Zn) were used as an adsorbent system for Cr3+ and Cr2O72− ions in aqueous solutions. Prior to the adsorption studies, both ferrites were characterized in order to determine the particle size distribution, morphology and available binding sites on the surface of the materials. Microscopy analysis demonstrated that both ferrites present two different size domains, at the micro- and nanoscale level, with the latter being able to self-assemble into larger particles. Fe-Ni/Zn/βCD presented smaller particles and a more homogeneous particle size distribution. Higher porosity for this MHM compared to Fe-Ni/Zn was observed by Brunauer–Emmett–Teller isotherms and positron-annihilation-lifetime spectroscopy. Based on the pKa values, potentiometric titrations demonstrated the presence of βCD in the inorganic matrix, indicating that the lamellar structures verified by transmission electronic microscopy can be associated with βCD assembled structures. Colloidal stability was inferred as a function of time at different pH values, indicating the sedimentation rate as a function of pH. Zeta potential measurements identified an amphoteric behavior for the Fe-Ni/Zn/βCD, suggesting its better capability to remove ions (cations and anions) from aqueous solutions compared to that of Fe-Ni/Zn.

Along the coast of central Chile, geographic trends of diversity have been inferred from literature compilations and museum collections based on species range limits for some taxonomic groups. However, spatially-intensive field-based assessments of macrobenthic species richness are largely missing. Over the course of a multiyear study (1998-2005), we characterized latitudinal patterns of rocky intertidal diversity at 18 sites along the coast of central Chile (29-36° S). At each site, the number of sessile and mobile macrobenthic species was quantified in 0.25 m² quadrats. Two estimators of local (alpha) diversity were used: observed local species richness, calculated from the asymptote of a species-rarefaction curve, and the Chao2 index, which takes into account the effect of rare species on estimates of local richness. We identified a total of 71 species belonging to 66 genera for a total of 86 taxa. The most diverse groups were herbivorous mollusks (27 taxa) and macroalgae (43 taxa). Diversity showed a complex spatial pattern with areas of high species richness interspersed with areas of low richness. In accordance with previous work, we found no trend in the number of herbivorous mollusks and an inverse and significant latitudinal gradient in the number of algal species. Our results highlight the need for taxonomically diverse assessments of biodiversity of the dominant taxa that conform intertidal communities.A lo largo de la costa de Chile central, los patrones geográficos de diversidad han sido inferidos a partir de revisiones literarias y colecciones de museos para algunos grupos taxonómicos. Sin embargo, aun no contamos con una evaluación integral, y en terreno, de la riqueza de especies macrobentónicas intermareales. En un estudio de largo plazo conducido entre 1998 y 2005 caracterizamos los patrones latitudinales en la biodiversidad del intermareal rocoso en 18 sitios a lo largo de la costa de Chile central (29-36° S). En cada sitio, el número de especies sésiles y móviles fue cuantificado en cuadrantes de 0.25 m². Usamos dos estimadores de la riqueza de especies: la riqueza local observada, correspondiente a la asíntota de la curva de acumulación de especies, y el índice Chao2, el cual considera el efecto de especies raras en la estimación de la diversidad local. Identificamos 71 especies pertenecientes a 66 géneros y a un total de 86 taxa. Los grupos más diversos fueron moluscos (27 taxa) y macroalgas (43 taxa). La riqueza de especies mostró un patrón complejo en el cual áreas de alta riqueza específica aparecieron intercaladas con áreas de baja riqueza. Además, observamos una alta variabilidad espacial en el número de especies herbívoras y un patrón latitudinal inverso en el número de especies algales. Nuestros resultados apuntan a la necesidad de incorporar una variedad de grupos taxonómicos y un rango de escalas espaciales en estudios de biodiversidad.

Western Patagonia harbors unique and sparsely studied terrestrial ecosystems that are threatened by land use changes and exposure to basin-scale climatic variability. We assessed the performance of two satellite vegetation indices derived from MODIS–Terra, EVI (Enhanced Vegetation Index) and NDVI (Normalized Difference Vegetation Index), over the northern and southern sectors of the Chiloé Island System (CIS) to advance our understanding of vegetation dynamics in the region. Then we examined their time-varying relationships with two climatic indices indicative of tropical and extratropical influence, the ENSO (El Niño–Southern Oscillation) and the Antarctic Oscillation (AAO) index, respectively. The 17-year time series showed that only EVI captured the seasonal pattern characteristic of temperate regions, with low (high) phenological activity during Autumn-Winter (Spring–Summer). NDVI saturated during the season of high productivity and failed to capture the seasonal cycle. Temporal patterns in productivity showed a weakened seasonal cycle during the past decade, particularly over the northern sector. We observed a non-stationary association between EVI and both climatic indices. Significant co-variation between EVI and the Niño–Southern Oscillation index in the annual band persisted from 2001 until 2008–2009; annual coherence with AAO prevailed from 2013 onwards and the 2009–2012 period was characterized by coherence between EVI and both climate indices over longer temporal scales. Our results suggest that the influence of large-scale climatic variability on local weather patterns drives phenological responses in the northern and southern regions of the CIS. The imprint of climatic variability on patterns of primary production across the CIS may be underpinned by spatial differences in the anthropogenic modification of this ecosystem, as the northern sector is strongly modified by forestry and agriculture. We highlight the need for field validation of satellite indices around areas of high biomass and high endemism, located in the southern sector of the island, in order to enhance the utility of satellite vegetation indices in the conservation and management of austral ecosystems.

Based on herbarium records, data bases and field studies in different localities of the Patia River valley in southwestern Colombia, a total of 297 vascular plants were previously known from this region. In this study the number was increased by 727 to a new total of 1024 species, which is a considerable increase in our knowledge of plant species richness in dry areas of southern Colombia. Those species are distributed among 556 genera in 130 families. Considering the number of species the following families stand out: Fabaceae (45 genera/119 species), Poaceae (52/101), Asteraceae (56/79), Malvaceae (23/44), Cyperaceae (7/41), Euphorbiaceae (10/39), Lamiaceae (13/31) and Solanaceae (9/31). The genera with the largest number of species are: Solanum (19 especies), Cyperus (16), Euphorbia (14), Hyptis (13), Senna (13), Sida (13), Piper (12), Peperomia (11) and Desmodium (10). Herbs are the predominant life-forms (53.77% of total species) followed by shrubs (24.58%). In the valley, pastures and crop fields are predominant; in some sectors, there are bushes and forest fragments in different successional stages; in the southern part, there are thorn bushes, with dominance of succulent plants belonging to the family Cactaceae.

The Pessegueiro Island Marine Protected Area (MPA), SW coast of Portugal, was implemented in 2011 with the purpose of protect biodiversity and prevent over-exploitation of commercially important fish species. Amongst those species are the Mediterranean moray (Muraena helena) and the European conger (Conger conger). In this context, the aim of this study was to assess the importance of this MPA as a refuge/feeding area for these species and to evaluate its location and size adequacy. The study was carried out during the summer of 2013 and a total of 19 morays and 6 congers were tagged with acoustic transmitters. An array of 19 automatic receivers was deployed with a sampling design that spatially covered the entire MPA. The data from the receivers was analysed through multivariate statistics (PERMANOVA), Kernel Density Estimation (KDE) and Network Analysis. Results showed that the Pessegueiro Island MPA is an important zone for both species since the tagged morays and congers spent 48% of the time within the area (average residency index). Also, KDE and Network Analysis showed that both species displayed relatively reduced home ranges, 20 ha in average for morays and 30 ha for congers, and the movements performed were limited to adjacent areas. Activity was more intense during night time for both species. Regarding morays, lunar cycle and sea conditions also seemed to influence their movement patterns. The data collected in this study highlight the importance of this MPA for the target species.

OBJETIVO: Determinar a importância da desnutrição como marcadora e preditora do óbito na cardiomiopatia dilatada idiopática na infância. MÉTODOS: Este é um estudo retrospectivo envolvendo 165 pacientes (setembro de 1979 a março de 2003). As variáveis analisadas foram sexo, idade e história de infecção viral nos últimos 3 meses, classe funcional da New York Heart Association (NYHA), percentil e desvio padrão do peso (índice z) e avaliação do estado nutricional. Foram realizadas 744 pesagens nos primeiros 72 meses e 93 no primeiro mês de evolução. Análise estatística: qui-quadrado, teste t de Student e análise de variância. Foram utilizados o valor alfa de 0,05 e o valor beta de 0,80. RESULTADOS: A idade no diagnóstico foi de 2,1±3,2 anos, com maior incidência nos menores de 2 anos (75,8%; IC95 = 68,5-82,1%) (p < 0,0001). A classe funcional III e IV foi observada em 81,2% (IC95 = 74,4-86,9%) (p < 0,0001), tendo todos os 40 óbitos ocorrido neste grupo (p = 0,0008). Na apresentação, a miocardite ocorreu em 39,4% (IC95 = 31,9-47,3%) (p = 0,0001). Houve forte associação entre miocardite e doença viral prévia (p = 0,0005) (RC = 3,15; IC95 = 1,55-6,44). A desnutrição na apresentação não influenciou o óbito (p = 0,10), porém a desnutrição evolutiva foi marcadora de óbito (p = 0,02) (RC = 3,21; IC95 = 1,04-9,95). Não houve diferença significativa no percentil de peso (p = 0,15) ou no índice z (p = 0,14) na apresentação. A média do percentil de peso e do índice z foram superiores nos sobreviventes (34,9+32,6 versus 8,6+16,0 e -0,62+1,43 versus -2,02+1,12) (p < 0,0001). A análise de variância demonstrou diferença significativa na evolução para o percentil de peso (p = 0,0417) e para o índice z (p = 0,0005) desde o primeiro mês de evolução. CONCLUSÃO: A avaliação do estado nutricional é de fácil execução, não implica ônus adicional e deve tornar-se rotina no seguimento do paciente com insuficiência cardíaca crônica.OBJECTIVE: To analyze the prognostic value of malnutrition in children with idiopathic dilated cardiomyopathy. METHODS: This is a retrospective study of 165 patients with idiopathic dilated cardiomyopathy, diagnosed from September 1979 to March 2003. It analyzed the following variables: gender, age, previous viral illness in the preceding 3 months, functional class according to the New York Heart Association (NYHA), evaluation of nutritional status (normal vs malnutrition), percentile and standard deviation (z index) of weight. Weight was measured 744 times during the first 72 months, 93 during the first month. Statistical analysis was performed by chi-squared, Student t test and analysis of variance for repeated measures (ANOVA). Ninety-five percent confidence intervals (CI95) and odds ratios (OR) were calculated. An alpha value of 0.05 and beta of 0.80 were used. RESULTS: Mean age at presentation was 2.2±3.2 years with higher incidence in those younger than 2 years (75.8%-CI95 = 68.5% to 82.1%) (p < 0.0001). NYHA classes III and IV were observed in 81.2% (CI95 = 74.4% to 86.9%) (p < 0.0001) and all 40 deaths were this group (p = 0.0008). At presentation, myocarditis occurred in 39.4% (CI95 = 31.9% to 47.3%) (p = 0.0001) and a high level of association between myocarditis and previous viral illness was observed (p = 0.0005) (OR = 3.15-CI95 = 1.55 to 6.44). Malnutrition at presentation did not influence death (p= 0.10), however progressive malnutrition was a marker for death (p = 0.02) (OR = 3.21-CI95 = 1.04 to 9.95). No significant differences weight percentiles (p = 0.15) or in z scores (p = 0.14) were observed. Observed mean weight percentiles (34.9+32.6 vs 8.6+16.0) (p < 0.0001) and z scores (-0.62+1.43 vs -2.02+1.12) (p < 0.0001) during the study period were greater among survivors. ANOVA demonstrated significant differences in weight percentile progression (p = 0.0417) and z scores (p = 0.0005) from the first month onwards. CONCLUSION: The evaluation of nutritional status. is easy to performer, it does not imply additional costs and should become routine for children with chronic heart failure.

Understanding the impacts of consumers on the abundance, growth rate, recovery and persistence of their resources across their distributional range can shed light on the role of trophic interactions in determining species range shifts. Here, we examined if consumptive effects of the intertidal grazer Scurria viridula positively influences the abundance and recovery from disturbances of the alga Mazzaella laminarioides at the edge of its geographic distributions in northern-central Chilean rocky shores. Through field experiments conducted at a site in the region where M. laminarioides overlaps with the polar range edge of S. viridula, we estimated the effects of grazing on different life stages of M. laminarioides. We also used long-term abundance surveys conducted across ~700 km of the shore to evaluate co-occurrence patterns of the study species across their range overlap. We found that S. viridula had positive net effects on M. laminarioides by increasing its cover and re-growth from perennial basal crusts. Probability of occurrence of M. laminarioides increased significantly with increasing density of S. viridula across the range overlap. The negative effect of S. viridula on the percentage cover of opportunistic green algae-shown to compete for space with corticated algae-suggests that competitive release may be part of the mechanism driving the positive effect of the limpet on the abundance and recovery from disturbance of M. laminarioides. We suggest that grazer populations contribute to enhance the abundance of M. laminarioides, facilitating its recolonization and persistence at its distributional range edge. Our study highlights that indirect facilitation can determine the recovery and persistence of a resource at the limit of its distribution, and may well contribute to the ecological mechanisms governing species distributions and range shifts.

There is a general consensus that marine herbivores can affect algal species composition and abundance, but little empirical work exists on the role of herbivores as modifiers of the spatial structure of resource assemblages. Here, we test the consumption/bulldozing effects of the molluscan grazer Enoplochiton niger and its influence on the spatial structure of a low intertidal community dominated by the bull kelp Durvillaea antarctica and the kelp Lessonia spicata. Through field experiments conducted at a rocky intertidal shore in north-central Chile (~30°-32°S), the edge of the grazer and algae geographic distributions, we estimated the strength and variability of consumptive effects of the grazer on different functional group of algae. We also used data from abundance field surveys to evaluate spatial co-occurrence patterns of the study species. Exclusion-enclosure experiments showed that E. niger maintained primary space available by preventing algal colonization, even of large brown algae species. The grazing activity of E. niger also reduced spatial heterogeneity of the ephemeral algal species, increasing bare space availability and variability through time in similar ways to those observed for the collective effect with other grazers. Overall, our result suggests that E. niger can be considered an important modifier of the spatial structure of the large brown algae-dominated community. Effects of E. niger on resource variability seem to be directly related to its foraging patterns, large body size, and population densities, which are all relevant factors for management and conservation of the large brown algae community. Our study thus highlights the importance of considering functional roles and identity of generalist consumers on spatial structure of the entire landscape.

This study hypothesizes the existence of three groups of sea lamprey Petromyzon marinus L. in Portugal (North/Central group, Tagus group, and Guadiana group), possibly promoted by seabed topography isolation during the oceanic phase of the life cycle. Within this context, our purpose was to analyze the existence of a stock structure on sea lamprey populations sampled in the major Portuguese river basins using both morphological characters and heart tissue fatty acid signature. In both cases, the multiple discriminant analysis revealed statistically significant differences among groups, and the overall corrected classification rate estimated from cross-validation procedure was particularly high for the cardiac muscle fatty acid profiles (i.e. 83.8%). Morphometric characters were much more useful than meristic ones to discriminate stocks, and the most important variables for group differentiation were eye length, second dorsal fin length and branchial length. Fatty acid analysis showed that all lampreys from the southern Guadiana group were correctly classified and not mixing with individuals from any other group, reflecting a typical heart fatty acid signature. Our results revealed that 89.5% and 72.2% of the individuals from the Tagus and North/Central groups, respectively, were also correctly classified, despite some degree of overlap between individuals from these groups. The fatty acids that contributed to the observed segregation were C16:0; C17:0; C18:1ω9; C20:3ω6 and C22:2ω6. Detected differences are probably related with environmental variables to which lampreys may have been exposed, which leaded to different patterns of gene expression. These results suggest the existence of three different sea lamprey stocks in Portugal, with implication in terms of management and conservation.

Environmental fluctuations can generate asynchronous species' fluctuations and community stability, due to compensatory dynamics of species with different environmental tolerances. We tested this hypothesis in intertidal hard-bottom communities of north-central Chile, where a persistent upwelling centre maintains a mosaic in sea surface temperatures (SST) over 10s of kilometres along the shore. Coastal upwelling implies colder and temporally more stable SST relative to downstream sites. Uni- and multivariate analyses of multiyear timeseries of SST and species abundances showed more asynchronous fluctuations and higher stability in sites characterised by warmer and more variable SST. Nevertheless, these effects were weakened after including data obtained in sites affected by less persistent upwelling centres. Further, dominant species were more stable in sites exposed to high SST variability. The strength of other processes that can influence community stability, chiefly statistical averaging and overyielding, did not vary significantly between SST regimes. Our results provide observational evidence supporting the idea that exogenously driven compensatory dynamics and the stabilising effects of dominant species can determine the stability of ecosystems facing environmental fluctuations.