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61.
The article analyses ‘local content’ in the strategies of multinational corporations (MNCs). Local content is explored as a link between MNCs and growth poles emerging through contract systems that encourage regional firms to connect with global networks entering a region. With a theoretical starting point in literature on local content and growth pole development, the analysis contributes to developing theories of growth poles by adding novel elements such as MNCs’ procurement strategies and their influence on growth poles through local content in contracts. Three aspects of MNCs’ contracts able to secure local content and thus increase contributions from extraction projects to regional development processes are analysed: (1) whether and how MNC projects are divided into subcontract modules, (2) the position and use of framework contracts, and (3) how transportation costs to sites are included in the biddings. It is concluded that further research on MNCs and local content would need to be aware of the following: factors that facilitate or maintain discrimination between bidders included and not included in global networks; reasons why advantages of geographical proximity are underexposed; and how public authorities (states) establish rules that give equality to local enterprises in their competition with firms entering from outside.  相似文献   
62.
The authors surveyed a representative sample of the Norwegian population (N = 4077) to examine perceptions of biodiversity loss and management, the relative importance of biodiversity loss to other environmental issues, and perceived implications of biodiversity loss. The results showed that 50% of the sample population saw biodiversity as a reality and major environmental issue, and 75% recognized that biodiversity loss occurs. Biodiversity loss was perceived as a lesser global environmental problem than environmental toxins, climate change, air and water pollution, and loss of rainforest, despite the fact that these topics can be difficult to separate since biodiversity loss is a function of other environmental problems. Loss of biodiversity was seen to have negative impacts on people's relationship to the natural environment, to impact environmental resilience, to be at least partly human-induced, and to be an issue of importance and relevance to the general public, not merely to the scientific community. Self-reported levels of knowledge of environmental topics were associated with increasing concern about consequences of reductions in species diversity. The authors conclude that efforts to increase public support for biodiversity conservation can be strengthened by increased emphasis on aesthetic, emotional and cultural aspects of biodiversity.  相似文献   
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Ocean Dynamics - With the continued rise in global mean sea level, operational predictions of tidal height and total water levels have become crucial for accurate estimations and understanding of...  相似文献   
64.
The characteristics of groundwater systems and groundwater contamination in Finland, Norway and Iceland are presented, as they relate to outbreaks of disease. Disparities among the Nordic countries in the approach to providing safe drinking water from groundwater are discussed, and recommendations are given for the future. Groundwater recharge is typically high in autumn or winter months or after snowmelt in the coldest regions. Most inland aquifers are unconfined and therefore vulnerable to pollution, but they are often without much anthropogenic influence and the water quality is good. In coastal zones, previously emplaced marine sediments may confine and protect aquifers to some extent. However, the water quality in these aquifers is highly variable, as the coastal regions are also most influenced by agriculture, sea-water intrusion and urban settlements resulting in challenging conditions for water abstraction and supply. Groundwater is typically extracted from Quaternary deposits for small and medium municipalities, from bedrock for single households, and from surface water for the largest cities, except for Iceland, which relies almost entirely on groundwater for public supply. Managed aquifer recharge, with or without prior water treatment, is widely used in Finland to extend present groundwater resources. Especially at small utilities, groundwater is often supplied without treatment. Despite generally good water quality, microbial contamination has occurred, principally by norovirus and Campylobacter, with larger outbreaks resulting from sewage contamination, cross-connections into drinking water supplies, heavy rainfall events, and ingress of polluted surface water to groundwater.  相似文献   
65.
The chemical composition and toxicity of a water soluble fraction (WSF) of oil versus the underlying water after in situ burning (ISB), has been studied in a laboratory experiment. A system for allowing water sampling after ISB was developed. Seawater samples and oil were collected prior to and immediately after ISB, and chemical analysis was conducted. The chemical characterization of the water showed that the disappearance of water soluble oil components during ISB was insignificant. Acute toxicity tests with the marine copepod Calanus finmarchicus and Microtox® bioassay was performed to establish LC50/EC50 values of the water. The results were compared with regular WAF systems with unburned weathered oil, and indicated no increase in toxicity in the underlying water after ISB.  相似文献   
66.
Observations of currents aimed to study the flow near a spawning aggregation reef, Gladden Spit off the coast of Belize, reveal unusually strong currents on 19–20 October 2009 (the current speed was over 1?m?s?1, when the mean and standard deviation are 0.2?±?0.12?m?s?1). During this short time, the water level was raised by 60–70?cm above normal in one place, but lowered by 10–20?cm in another location just 2?km away. The temperature dropped by over 2°C within a few hours. Analyses of local and remote sensing data suggest that a rare combination of an offshore Caribbean cyclonic eddy, a short-lived local tropical storm, and a Spring tide, all occurred at the same time and creating a “perfect storm” condition that resulted in the unusual event. High-resolution simulations and momentum balance analysis demonstrate how the unique shape of the coral reef amplified the coastal current through nonlinear flow–topography interactions. The suggested mechanism for the water level change is different than the classical wind-driven storm surge process. The study has implications for the influence of external forcing on mixing processes and physical–biological interactions near coral reefs.  相似文献   
67.
In March 2011, the Ecophysiology and Genetics Working Groups of the European Science Foundation COST Action ES 0906, entitled Seagrass Productivity: From Genes to Ecosystem Management, organized an exploratory workshop entitled “Linking Ecophysiology and Ecogenomics in Seagrass Systems”. The goal of the workshop was to discuss how to integrate comparative gene expression studies with physiological processes such as photosynthetic performance, carbon and nitrogen utilization and environmental adaptation. The main questions discussed for integrative research related to mechanisms of carbon utilization, light requirements, temperature effects and natural variation in pH and ocean acidification. It was concluded that the seagrass research community is still in the nascent stages of linking ecophysiology with genomic responses, as carbon and nitrogen metabolism of seagrasses have not been sufficiently well studied. Likewise, genomic approaches have only been able to assign meaningful interpretations to a handful of differentially expressed genes. Nevertheless, the way forward has been established.  相似文献   
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Basin modelling studies are carried out in order to understand the basin evolution and palaeotemperature history of sedimentary basins. The results of basin modelling are sensitive to changes in the physical properties of the rocks in the sedimentary sequences. The rate of basin subsidence depends, to a large extent, on the density of the sedimentary column, which is largely dependent on the porosity and therefore on the rate of compaction. This study has tested the sensitivity of varying porosity/depth curves and related thermal conductivities for the Cenozoic succession along a cross‐section in the northern North Sea basin, offshore Norway. End‐member porosity/depth curves, assuming clay with smectite and kaolinite properties, are compared with a standard compaction curve for shale normally applied to the North Sea. Using these alternate relationships, basin geometries of the Cenozoic succession may vary up to 15% from those predicted using the standard compaction curve. Isostatic subsidence along the cross‐section varies 2.3–4.6% between the two end‐member cases. This leads to a 3–8% difference in tectonic subsidence, with maximum values in the basin centre. Owing to this, the estimated stretching factors vary up to 7.8%, which further gives rise to a maximum difference in heat flow of more than 8.5% in the basin centre. The modelled temperatures for an Upper Jurassic source rock show a deviation of more than 20 °C at present dependent on the thermal conductivity properties in the post‐rift succession. This will influence the modelled hydrocarbon generation history of the basin, which is an essential output from basin modelling analysis. Results from the northern North Sea have shown that varying compaction trends in sediments with varying thermal properties are important parameters to constrain when analysing sedimentary basins.  相似文献   
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