Habitat filtering determines spatial variation of macroinvertebrate community traits in northern headwater streams

Although our knowledge of the spatial distribution of stream organisms has been increasing rapidly in the last decades, there is still little consensus about trait-based variability of macroinvertebrate communities within and between catchments in near-pristine systems. Our aim was to examine the taxonomic and trait based stability vs. variability of stream macroinvertebrates in three high-latitude catchments in Finland. The collected taxa were assigned to unique trait combinations (UTCs) using biological traits. We found that only a single or a highly limited number of taxa formed a single UTC, suggesting a low degree of redundancy. Our analyses revealed significant differences in the environmental conditions of the streams among the three catchments. Linear models, rarefaction curves and beta-diversity measures showed that the catchments differed in both alpha and beta diversity. Taxon- and trait-based multivariate analyses also indicated that the three catchments were significantly different in terms of macroinvertebrate communities. All these findings suggest that habitat filtering, i.e., environmental differences among catchments, determines the variability of macroinvertebrate communities, thereby contributing to the significant biological differences among the catchments. The main implications of our study is that the sensitivity of trait-based analyses to natural environmental variation should be carefully incorporated in the assessment of environmental degradation, and that further studies are needed for a deeper understanding of trait-based community patterns across near-pristine streams

Catalytic oxidation of volatile organic compounds (n-hexane, benzene, toluene, o-xylene) promoted by cobalt catalysts supported on γ-Al2O3-CeO2

Cobalt catalysts supported on γ-alumina, ceria and γ-alumina-ceria, with 10 or 20%wt of cobalt load, prepared by the wet impregnation method and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), field emission transmission electron microscopy (FETEM), N2 adsorption-desorption isotherms (BET/BJH methods), energy-dispersive X-ray spectroscopy (EDX), X-ray photoemission spectroscopy (XPS), O2-chemisorption and temperature programmed reduction (TPR) were used to promote the oxidation of volatile organic compounds (n-hexane, benzene, toluene and o-xylene). For a range of low temperatures (50-350 °C), the activity of the catalysts with a higher cobalt load (20% wt) was greater than that of the catalysts with a lower cobalt load (10% wt). The Co/γ-Al2O3-CeO2 catalytic systems presented the best performances. The results obtained in the characterization suggest that the higher catalytic activity of the Co20/γ-Al2O3-CeO2 catalyst may be attributed to the higher metal content and amount of oxygen vacancies, as well as the effects of the interaction between the cobalt and the alumina and cerium oxides

Functional diversity and traits assembly patterns of benthic macrofaunal communities in the southern North Sea

The study of ecosystem functioning – the fluxes of energy and material through biotic and abiotic components of an ecosystem – is becoming increasingly important in benthic ecological research. We investigated the functional structure of macrozoobenthic communities at four long-term sampling sites in the southern North Sea using biological traits assigned to life history, morphological and behavioural characteristics. The “typical” species of the macrofaunal assemblages at the sampling sites was characterized by small to medium body size, infaunal burrowing life style, deposit feeding habit, omnivory diet type, short to medium life span, gonochoristic sexual differentiation, 330 macrofaunal taxa have been compiled in a comprehensive database

Emissivity, catalycity and microstructural characterization of ZrB2–SiCfiber based UHTC at high temperature in a non-equilibrium air plasma flow

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XXX.—Notice of the discovery of a new Fossil Animal, forming a link between the Ichthyosaurus and Crocodile, together with general remarks on the Osteology of the Ichthyosaurus.

In the course of a series of observations on the organic remains contained in the lias in the vicinity of Bristol, my attention was particularly attracted by the numerous vertebræ of oviparous quadrupeds occuring in that formation. Of these a considerable portion obviously belonged to the Ichthyosaurus; the remaining, and larger division, presented vertebræ of forms considerably differing from each other, but which, from some general analogies, I was persuaded had all belonged to different places in the vertebral column of a single species; and I ventured even to point out those places, from a comparison with those of the crocodile to which they bore a strong general resemblance, yet at the same time combined with so many material points of difference, as to prove that the animal from which they were derived must have constituted a separate genus. At this period, I was fortunate enough to associate in my researches a colleague equally able and zealous, whose name stands at the head of this paper. The numerous important and illustrative specimens which he placed at my disposal, proved of material aid, and still more so his general acquaintance with the subject, of which I subsequently enjoyed the fullest advantage; so that the facts now submitted to the Society must be considered as the fruit of inquiries prosecuted by us in common. A skeleton of the animal in question, deficient only in the bones of the head, preserved in the well known collection of Col. Birch, (who most liberally allowed</jats:p

WLCG Transfers Dashboard: a Unified Monitoring Tool for Heterogeneous Data Transfers

The Worldwide LHC Computing Grid provides resources for the four main virtual organizations. Along with data processing, data distribution is the key computing activity on the WLCG infrastructure. The scale of this activity is very large, the ATLAS virtual organization (VO) alone generates and distributes more than 40 PB of data in 100 million files per year. Another challenge is the heterogeneity of data transfer technologies. Currently there are two main alternatives for data transfers on the WLCG: File Transfer Service and XRootD protocol. Each LHC VO has its own monitoring system which is limited to the scope of that particular VO. There is a need for a global system which would provide a complete cross-VO and cross-technology picture of all WLCG data transfers. We present a unified monitoring tool – WLCG Transfers Dashboard – where all the VOs and technologies coexist and are monitored together. The scale of the activity and the heterogeneity of the system raise a number of technical challenges. Each technology comes with its own monitoring specificities and some of the VOs use several of these technologies. This paper describes the implementation of the system with particular focus on the design principles applied to ensure the necessary scalability and performance, and to easily integrate any new technology providing additional functionality which might be specific to that technology