2,039 research outputs found

    Toward a new generation of effective problem solvers and project-oriented applied ecologists

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    Abstract. In an era of environmental crises, conservation and management strategies need a new generation of applied ecologists. Here, we stimulate the next-generation applied ecologists to acquire a pragmatic mentality of problems solvers in real contexts, using the wide arsenal of concepts, approaches and techniques available in the project management (PM) arena using a road map based on the main steps of conservation project cycle. The acquisition of the conceptual and operational framework of PM can allow the next-generation applied ecologists to take on a more important role in nature conservation strategies: from data samplers, analyzers and interpreters to suppliers of solutions and decisions driving changes in species' targets inhabiting real contexts. Since the high number of applied ecologists, this change in approach (from analytical to operational) could make the difference in conservation science. We also provided, as a conceptual framework, a set of suggestions and approaches useful to facilitate this change

    Scalar Field Theory on Non-commutative Snyder Space-Time

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    We construct a scalar field theory on the Snyder non-commutative space-time. The symmetry underlying the Snyder geometry is deformed at the co-algebraic level only, while its Poincar\'e algebra is undeformed. The Lorentz sector is undeformed at both algebraic and co-algebraic level, but the co-product for momenta (defining the star-product) is non-co-associative. The Snyder-deformed Poincar\'e group is described by a non-co-associative Hopf algebra. The definition of the interacting theory in terms of a non-associative star-product is thus questionable. We avoid the non-associativity by the use of a space-time picture based on the concept of realization of a non-commutative geometry. The two main results we obtain are: (i) the generic (namely for any realization) construction of the co-algebraic sector underlying the Snyder geometry and (ii) the definition of a non-ambiguous self interacting scalar field theory on this space-time. The first order correction terms of the corresponding Lagrangian are explicitly computed. The possibility to derive Noether charges for the Snyder space-time is also discussed.Comment: 10 pages; v2: introduction rewritten, co-algebraic analysis improved, references added; to appear in PR

    The Dynamics of the Global Monsoon: Connecting Theory and Observations

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    Earth's monsoons are complex systems, governed by both large-scale constraints on the atmospheric general circulation and regional interactions with continents and orography, and coupled to the ocean. Monsoons have historically been considered as distinct regional systems, and the prevailing view has been, and remains, an intuitive picture of monsoons as a form of large-scale sea breeze, driven by land-sea contrast. However, climate dynamics is seldom intuitive. More recently, a perspective has emerged within the observational and Earth system modeling communities of a global monsoon that is the result of a seasonally migrating tropical convergence zone, intimately connected to the global tropical atmospheric overturning and localized by regional characteristics. Parallel with this, over the past decade, much theoretical progress has been made in understanding the fundamental dynamics of the seasonal Hadley cells and Intertropical Convergence Zones via the use of hierarchical modeling approaches, including highly idealized simulations such as aquaplanets. Here we review the theoretical progress made, and explore the extent to which these theoretical advances can help synthesize theory with observations and understand differing characteristics of regional monsoons. We show that this theoretical work provides strong support for the migrating convergence zone picture, allows constraints on the circulation to be identified via the momentum and energy budgets, and lays out a framework to assess variability and possible future changes to the monsoon. Limitations of current theories are discussed, including the need for a better understanding of the influence of zonal asymmetries and transients on the large-scale tropical circulation

    Dune plants as a sink for beach litter: The species-specific role and edge effect on litter entrapment by plants

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    Anthropogenic litter accumulates along coasts worldwide. In addition to the flowing litter load, wind, sea currents, geomorphology and vegetation determine the distribution of litter trapped on the sandy coasts. Although some studies highlighted the role of dune plants in trapping marine litter, little is known about their efficiency as sinks and about the small-scale spatial distribution of litter across the dune area. Here, we explore these gaps by analysing six plant species widespread in Mediterranean coastal habitats, namely Echinophora spinosa, Limbarda crithmoides, Anthemis maritima, Pancratium maritimum, Thinopyrum junceum, and Salsola kali. The present study analyses for the first time the capture of litter by dune vegetation at a multi-species level, considering their morphological structure. Data on plastic accumulation on dune plants were compared with unvegetated control plots located at embryo-dune and foredune belts. We found that dunal plants mainly entrapped macrolitter (> 0.5 cm). Particularly, E. spinosa, L. crithmoides, A. maritima and P. maritimum mostly accumulated litter in the embryo dune while T. junceum and S. kali entrapped more in the foredune area. Moreover, beach litter was mainly blocked at the edge of the plant patches rather than in the core, highlighting the ‘Plant-edge litter effect’. As A. maritima and S. kali entrapped respectively more litter in embryo and foredune habitats, these species could be used to monitor and recollect litter. In this light, our findings provide further insight into the role of dune plants in the beach litter dynamics, suppling useful information for beach clean-up actions
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