Isotopic niche variability in macroconsumers of the East Scotia Ridge (Southern Ocean) hydrothermal vents: What more can we learn from an ellipse?

Aspects of between-individual trophic niche width can be explored through the isotopic niche concept. In many cases isotopic variability can be influenced by the scale of sampling and biological characteristics including body size or sex. Sample size-corrected (SEAc) and Bayesian (SEAb) standard ellipse areas and generalised least squares (GLS) models were used to explore the spatial variability of δ13C and δ15N in Kiwa tyleri (decapod), Gigantopelta chessoia (peltospirid gastropod) and Vulcanolepas scotiaensis (stalked barnacle) collected from 3 hydrothermal vent field sites (E2, E9N and E9S) on the East Scotia Ridge (ESR), Southern Ocean. SEAb only revealed spatial differences in isotopic niche area in male K. tyleri. However, the parameters used to draw the SEAc, eccentricity (E) and angle of the major SEAc axis to the x-axis (θ), indicated spatial differences in the relationships between δ13C and δ15N in all 3 species. The GLS models indicated that there were spatial differences in isotope-length trends, which were related to E and θ of the SEAc. This indicated that E and θ were potentially driven by underlying trophic and biological processes that varied with body size. Examination of the isotopic niches using standard ellipse areas and their parameters in conjunction with length-based analyses provided a means by which a proportion of the isotopic variability within each species could be described. We suggest that the parameters E and θ offer additional ecological insight that has so far been overlooked in isotopic niche studies

Geneses and Progress of the World Campaign and Council for The Biosphere

Starting with some clarifying definitions of the senses in which the key words in its title are used, this paper outlines the concept and actuality of The Biosphere, which is defined as ‘The integrated living and life-supporting system comprising the peripheral envelope of Planet Earth together with its surrounding atmosphere so far down, and up, as any form of life exists naturally.' Two ‘round- dozens' of the key facts about The Biosphere are then given—including Mankind's constitution of an integral part of it as well as utter dependence on it and yet increasing threat to it—with emphasis on the vital importance of understanding and fostering it as our own and Nature's sole life-support. To such understanding and concomitant fostering for survival, education is the key, and to such ends the World Campaign for The Biosphere was developed through various stages and finally declared on World Environment Day 1982 with the No. 1 aim of making the concept and reality of ‘Our Biosphere intimately and personally meaningful to people of all ages and cultures throughout the world.