63 research outputs found

    DO INDUSTRIAL CLASSIFICATIONS NEED RE-INVENTINg? AN ANALYSIS OF THE RELEVANCE OF THE U.S. SIC SYSTEM FOR PRODUCTIVITY RESEARCH

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    Two separate empirical investigations into the conceptual structure underlying the U.S. SIC were undertaken. Government industry specialists and industry classification experts reviewed individual4-digit U.S. SICs and judgmentally determined if these industries had been constructed by grouping similar production processes, or, alternatively, by grouping similar markets. Independently, an algorithm derived from the diversification index developed by Gollop and Monahan (1991) was used to measure the heterogeneity of establishment production functions, by 4-digit industry, using the Census Longitudinal Research Database file. The two reviews yielded broadly similar results: Only about one fifth of US. industries have been designed to be approximately consistent with aggregation conditions derived from production theory

    Warmer, deeper and greener mixed layers in the north Atlantic subpolar gyre over the last 50 years.

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    Shifts in global climate resonate in plankton dynamics, biogeochemical cycles, and marine food webs. We studied these linkages in the North Atlantic Subpolar Gyre (NASG), which hosts extensive phytoplankton blooms. We show that phytoplankton abundance increased since the 1960s in parallel to a deepening of the mixed layer and a strengthening of winds and heat losses from the ocean, as driven by the low frequency of the North Atlantic Oscillation (NAO). In parallel to these bottom-up processes, the top-down control of phytoplankton by copepods decreased over the same time period in the western NASG, following sea surface temperature changes typical of the Atlantic Multi-decadal Oscillation (AMO). While previous studies have hypothesized that climate-driven warming would facilitate seasonal stratification of surface waters and long-term phytoplankton increase in subpolar regions, here we show that deeper mixed layers in the NASG can be warmer and host a higher phytoplankton biomass. These results emphasize that different modes of climate variability regulate bottom-up (NAO control) and top-down (AMO control) forcing on phytoplankton at decadal time scales. As a consequence, different relationships between phytoplankton, zooplankton and their physical environment appear, subject to the disparate temporal scale of the observations (seasonal, interannual, or decadal). The prediction of phytoplankton response to climate change should be built upon what is learnt from observations at the longest time scales. This article is protected by copyright. All rights reserved

    Essential ocean variables for global sustained observations of biodiversity and ecosystem changes

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    International audience; Sustained observations of marine biodiversity and ecosystems focused on specific conservation and management problems are needed around the world to effectively mitigate or manage changes resulting from anthropogenic pressures. These observations, while complex and expensive, are required by the international scientific, governance and policy communities to provide baselines against which the effects of human pressures and climate change may be measured and reported, and resources allocated to implement solutions. To identify biological and ecological essential ocean variables (EOVs) for implementation within a global ocean observing system that is relevant for science, informs society, and technologically feasible, we used a driver-pressure-state-impact-response (DPSIR) model. We (1) examined relevant international agreements to identify societal drivers and pressures on marine resources and ecosystems, (2) evaluated the temporal and spatial scales of variables measured by 100+ observing programs, and (3) analysed the impact and scalability of these variables and how they contribute to address societal and scientific issues. EOVs were related to the status of ecosystem components (phytoplankton and zoo-plankton biomass and diversity, and abundance and distribution of fish, marine turtles, birds and mammals), and to the extent and health of ecosystems (cover and composition of hard coral, seagrass, mangrove and macroalgal canopy). Benthic invertebrate abundance and distribution and microbe diversity and biomass were identified as emerging EOVs to be developed based on emerging requirements and new technologies. The temporal scale at which any shifts in biological systems will be detected will vary across the EOVs, the properties being monitored and the length of the existing time-series. Global implementation to deliver useful products will require collaboration of the scientific and policy sectors and a significant commitment to improve human and infrastructure capacity across the globe, including the development of new, more automated observing technologies, and encouraging the application of international standards and best practices

    From Science to Evidence – How Biodiversity Indicators Can Be Used for Effective Marine Conservation Policy and Management

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    Indicators are effective tools for summarizing and communicating key aspects of ecosystem state and have a long record of use in marine pollution and fisheries management. The application of biodiversity indicators to assess the status of species, habitats, and functional diversity in marine conservation and policy, however, is still developing and multiple indicator roles and features are emerging. For example, some operational biodiversity indicators trigger management action when a threshold is reached, while others play an interpretive, or surveillance, role in informing management. Links between biodiversity indicators and the pressures affecting them are frequently unclear as links can be obscured by environmental change, data limitations, food web dynamics, or the cumulative effects of multiple pressures. In practice, the application of biodiversity indicators to meet marine conservation policy and management demands is developing rapidly in the management realm, with a lag before academic publication detailing indicator development. Making best use of biodiversity indicators depends on sharing and synthesizing cutting-edge knowledge and experience. Using lessons learned from the application of biodiversity indicators in policy and management from around the globe, we define the concept of ‘biodiversity indicators,’ explore barriers to their use and potential solutions, and outline strategies for their effective communication to decision-makers
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