35 research outputs found

    Comparison of survey methods for estimating abundance of harbor seals (Phoca vitulina) in glacial fjords

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    The importance of glacial ice habitats to harbor seals (Phoca vitulina) in Alaska has become increasingly apparent. However, enumerating harbor seals hauled out on ice in glacial fjords has been difficult. At Johns Hopkins Inlet in Glacier Bay, Alaska, we compared a shore-based counting method to a large-format aerial photography method to estimate seal abundance. During each aerial survey, shore-based observers simultaneously counted seals from an observation post. Both survey methods incurred errors in double-counting and missing seals, especially when ice movements caused seals to drift between survey zones. Advantages of shore-based counts included the ability to obtain multiple counts for relatively little cost, distinguish pups from adults, and to distinguish mobile seals from shadows or glacial debris of similar size. Aerial photography provided a permanent record of each survey, allowing both a reconciliation of counts in overlapping zones and the documentation of the spatial distribution of seals and ice within the fjord

    Consequences of Covid-19 on the Social Isolation of the Chinese Economy: Accounting for the Role of Reduction in Carbon Emissions

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    The main contribution of the present study to the energy literature is linked to the interaction between economic growth and pollution emission amidst globalization. Unlike other studies, this research explores the effect of economic and social isolation as a dimension of globalization. This allows underpinning the effects on the Chinese economic development of the isolation phenomenon as a consequence of coronavirus (COVID-19). To this end, annual time frequency data is used to achieve the hypothesized claims. The study resolutions include (i) The existence of a long-run equilibrium bond between the outlined variables (ii) The long-run estimates suggest that the Chinese economy over the investigated period, is inelastic to pollutant–driven economic growth as reported by the dynamic ordinary least squares, fully modified ordinary least squares and canonical regressions with a magnitude of 0.09%. (iii) The Chinese isolation is less responsive to its economic growth while the country political willpower is elastic as demonstrated by current government commitment to dampen the effect of the COVID-19 pandemic. This is marked by the aggressive response on the government officials resolute by flattening the exponential impact of the pandemic. Based on these robust results some far-reaching policy implication(s) are underlined in the concluding remark section

    TRY plant trait database – enhanced coverage and open access

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    Plant traits - the morphological, anatomical, physiological, biochemical and phenological characteristics of plants - determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of trait‐based plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits - almost complete coverage for ‘plant growth form’. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and trait–environmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives
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