Multiscale scenarios for nature futures Targets for human development are increasingly connected with targets for nature, however, existing scenarios do not explicitly address this relationship. Here, we outline a strategy to generate scenarios centred on our relationship with nature to inform decision-making at multiple scales.

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Mussels often act as ecosystem engineers in rocky intertidal habitats, favoring the occurrence of many small invertebrates by increasing habitat complexity and improving local environmental conditions. This study tests the hypothesis that invertebrate assemblages from intertidal mussel beds differ between wave-sheltered and wave-exposed habitats. To this aim, we surveyed exposed and sheltered sites spanning 350 km of coastline in Nova Scotia, Canada. We identified all invertebrates and measured their abundance in replicate quadrats that were fully covered by mussels. In total, we found 50 invertebrate taxa living in these mussel beds. Multivariate analyses revealed that the composition of invertebrate assemblages differed significantly between both habitat types. Exposed habitats supported a greater species richness, and the species that mainly explained the compositional difference between both environments were more abundant in exposed ones. Assemblages were taxonomically dominated by arthropods, annelids, and molluscs and numerically dominated by tubificid oligochaetes regardless of exposure. Our results suggest that exposed habitats may favor the occurrence of filterfeeders, such as barnacles, and sheltered habitats the occurrence of predators, such as small crabs and sea stars, in intertidal mussel beds from the NW Atlantic coast.

Ecosystem engineers can modify habitat, creating structural microhabitats. This structural complexity can affect species richness. Marine ecosystem engineers are able to produce local effects in combination with environmental variables (e.g. to create more humid habitat during low tides). We tested the hypotheses that if there is a relationship between mussel morphology and environmental factors, mussels would be larger at warmer than at cooler locations, and in areas where 2 species of mussels overlap, size and biomass will decrease and density will increase. At a smaller scale, we predicted that there is a relationship between the assemblage structure and hardness of the substratum and sediment content of a mussel bed. Using a nested design, we measured density, biomass and size of 2 species of mussels, Brachidontes rodriguezii and Perumytilus (Brachidontes) purpuratus, and diversity of species associated with mussel beds at 2 rocky intertidal sites at each of 4 shores along the northern Argentinean coast. These variables were correlated with oceanographic conditions and local characteristics. Significant correlations were found between intertidal assemblages and local factors. The largest specimens of B. rodriguezii and P. purpuratus were found at the warmer shores. In areas where they overlapped, size, biomass and density of P. purpuratus were lower, although B. rodriguezii did not change. The mean abundance of invertebrates associated with a mussel bed showed significant differences among shores. These 2 species of mytilids coexist over a small area, and although these species are very similar in their biological and ecological function, the fauna associated with their matrices are very different. KEY WORDS: Spatial variations · Rocky shores · Ecosystem engineers · Environmental factors · Benthos · Southwest AtlanticResale or republication not permitted without written consent of the publisher Aquat Biol 18: 91-103, 2013 physically harsh conditions (Murray et al. 2002). In addition, local meteorological conditions such as wind, precipitation and climate anomalies can cause large impacts on ecosystems (Mantua & Hare 2002). The species that live in these habitats survive in variable and sometimes extreme physical conditions. One factor that correlates well with the abundance and diversity of species is water temperature, particularly over latitudinal gradients (Rohde 1992). Many other factors also correlate with species distributions and patterns of abundance (e.g. physical interactions between organisms and their habitats, behavioural and physiological adaptations; Burrows & Hughes 1989).Changes in the structure of assemblages of intertidal species at the scales of hundreds of kilometres and hundreds of metres may be attributed to differences in topography, substrate type, hydrodynamic conditions, intertidal elevation, wave exposure, climatic differences or variation in primary productivity (Araujo et al. 2005, Liuzzi & López Gappa 2008, Burrows et al. 2009. Spatial variability at the scale of t...

Assemblages associated with intertidal rocky shores were examined for large scale distribution patterns with specific emphasis on identifying latitudinal trends of species richness and taxonomic distinctiveness. Seventy-two sites distributed around the globe were evaluated following the standardized sampling protocol of the Census of Marine Life NaGISA project (www.nagisa.coml.org). There were no clear patterns of standardized estimators of species richness along latitudinal gradients or among Large Marine Ecosystems (LMEs); however, a strong latitudinal gradient in taxonomic composition (i.e., proportion of different taxonomic groups in a given sample) was observed. Environmental variables related to natural influences were strongly related to the distribution patterns of the assemblages on the LME scale, particularly photoperiod, sea surface temperature (SST) and rainfall. In contrast, no environmental variables directly associated with human influences (with the exception of the inorganic pollution index) were related to assemblage patterns among LMEs. Correlations of the natural assemblages with either latitudinal gradients or environmental variables were equally strong suggesting that neither neutral models nor models based solely on environmental variables sufficiently explain spatial variation of these assemblages at a global scale. Despite the data shortcomings in this study (e.g., unbalanced sample distribution), we show the importance of generating biological global databases for the use in large-scale diversity comparisons of rocky intertidal assemblages to stimulate continued sampling and analyses.

The rapid, global spread of COVID-19, and the measures intended to limit or slow its propagation, are having major impacts on diverse sectors of society. Notably, these impacts are occurring in the context of other anthropogenic-driven threats including global climate change. Both anthropogenic stressors and the COVID-19 pandemic represent significant economic challenges to aquaculture systems across the globe, threatening the supply chain of one of the most important sources of animal protein, with potential disproportionate impacts on vulnerable communities. A web survey was conducted in 47 countries in the midst of the COVID-19 pandemic to assess how aquaculture activities have been affected by the pandemic, and to explore how these impacts compare to those from climate change. A positive correlation between the effects of the two categories of drivers was detected, but analysis suggests that the pandemic and the anthropogenic stressors affect different parts of the supply chain. The immediate measurable reported losses varied with aquaculture typology (land vs. marine, and intensive vs. extensive). A comparably lower impact on farmers reporting the use of integrated multitrophic aquaculture (IMTA) methods suggests that IMTA might enhance resilience to multiple stressors by providing different market options under the COVID-19 pandemic. Results emphasize the importance of assessing detrimental effects of COVID-19 under a multiple stressor lens, focusing on areas that have already locally experienced economic loss due to anthropogenic stressors in the last decade. Holistic policies that simultaneously address other ongoing anthropogenic stressors, rather than focusing solely on the acute impacts of COVID-19, are needed to maximize the long-term resilience of the aquaculture sector.

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This study examined spatial relationships between rocky shore polychaete assemblages and environmental variables over broad geographical scales, using a database compiled within the Census of Marine Life NaGISA (Natural Geography In Shore Areas) research program. The database consisted of abundance measures of polychaetes classified at the genus and family levels for 74 and 93 sites, respectively, from nine geographic regions. We tested the general hypothesis that the set of environmental variables emerging as potentially important drivers of variation in polychaete assemblages depend on the spatial scale considered. Through Moran's eigenvector maps we indentified three submodels reflecting spatial relationships among sampling sites at intercontinental (>10000 km), continental (1000–5000 km) and regional (20–500 km) scales. Using redundancy analysis we found that most environmental variables contributed to explain a large and significant proportion of variation of the intercontinental submodel both for genera and families (54% and 53%, respectively). A subset of these variables, organic pollution, inorganic pollution, primary productivity and nutrient contamination was also significantly related to spatial variation at the continental scale, explaining 25% and 32% of the variance at the genus and family levels, respectively. These variables should therefore be preferably considered when forecasting large-scale spatial patterns of polychaete assemblages in relation to ongoing or predicted changes in environmental conditions. None of the variables considered in this study were significantly related to the regional submodel.