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1.
Herbarium plants were used as a material to study possible long-term changes in mineral elements of forest plants. Plants from South Norway collected in the period 1870 to 1930 were compared to plants collected in 1982. Relative to mineral contents in plants from 1870 to 1930, the 1982 material showed elevated levels of Zn, Cd, Rb, K, Mn and Ti and decreased levels of Sr, B, Ca and Mo in some of the plant species analysed. Most of these differences may be explained by changes in the environmental conditions, due to differences in chemical composition of precipitation, accelerated soil acidification and subsequent increasing mineral weathering. Consequently analysis of herbarium plants seems to provide valuable information about preindustrial levels of mineral elements and seems to detect changes in mineral elements brought about by recent anthropogenic activity.  相似文献   
2.

Rock ptarmigan (Lagopus muta) and willow ptarmigan (L. lagopus) are Arctic birds with a circumpolar distribution but there is limited knowledge about their status and trends across their circumpolar distribution. Here, we compiled information from 90 ptarmigan study sites from 7 Arctic countries, where almost half of the sites are still monitored. Rock ptarmigan showed an overall negative trend on Iceland and Greenland, while Svalbard and Newfoundland had positive trends, and no significant trends in Alaska. For willow ptarmigan, there was a negative trend in mid-Sweden and eastern Russia, while northern Fennoscandia, North America and Newfoundland had no significant trends. Both species displayed some periods with population cycles (short 3–6 years and long 9–12 years), but cyclicity changed through time for both species. We propose that simple, cost-efficient systematic surveys that capture the main feature of ptarmigan population dynamics can form the basis for citizen science efforts in order to fill knowledge gaps for the many regions that lack systematic ptarmigan monitoring programs.

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3.
In the OZIPP (ozone isopleth plotting package, developed by United States Environmental Protection Agency) a number of model specific assumptions with respect to chemical and physical processes are made. These assumptions are introduced into an alternative model developed at AERE Harwell, United Kingdom, in which a detailed chemistry and mixture of organic emissions is included. The impact on the AERE Harwell model results of the assumptions made in OZIPP of omitting ground removal of ozone (O3) and peroxyacetylnitrate (PAN) and of employing an incomplete PAN chemistry and adopting a reaction rate coefficient of the key reaction NO + HO2 → NO2 + OH which is a factor 10 lower than the accepted value, are discussed. The composition of the organic emissions is an important model parameter, and it is shown how grouping of nonmethane hydrocarbon (NMHC) emissions into a small group of NMHC thought to be representative, often implies that O3 and other pollutants are overestimated. The O3 isopleth diagram for London constructed using the AERE Harwell model gives a somewhat different picture from that obtained with OZIPP. OZIPP in general predicts that NOx control or combined hydrocarbon(HC) and NOx control is efficient with respect to O3 reduction whilst the AERE Harwell model predicts that HC control alone usually is more efficient than combined HC and NOx control. Furthermore NOx control alone may often increase the O3 burden downwind in the AERE Harwell model.  相似文献   
4.
Do natural resources reduce social trust? This paper reviews the literature on natural resources and on trust. The existing theoretical and empirical literature suggests that natural resources can reduce trust through several indirect mechanisms. Notably, studies show that natural resources lead to institutional degradation, corruption, inequality, and civil war, all of which have been associated with reduced trust. In addition, game theoretical work on windfall gains suggests that there may be direct effect of natural resources on trust. This paper tests empirically whether there is a direct effect of natural resources on trust (The Pearl Hypothesis), using cross-country data. The results indicate that no such direct effect exists, but we find a significant effect on trust of intermediate variables affected by natural resources, such as institutions, corruption, inequality and/or civil war. Importantly, the relationship between corruption and trust turns out to be non-linear, indicating that the effect of natural resources on trust depends on the initial corruption level of a country. In highly corrupt societies, institutional improvements that reduce corruption may also undermine trust, which poses difficult challenges for anti-corruption policy.  相似文献   
5.
Urinary copper (Cu), nickel (Ni) and cobalt (Co) concentrations were determined for 127 Cu refinery workers (40 females, 87 males), with values of the 95% upper confidence interval of the geometric mean in nmol per mmol creatinine of 89 (Ni), 42 (Cu) and 3.4 (Co) for electrorefinery workers. In the pyrometallurgical departments, the corresponding concentrations were 37 (Ni), 99 (Cu) and 11 (Co). Female workers had higher Co urinary concentrations than males (p< or = 0.05) while no gender difference was observed for Cu and Ni. Inter-elemental correlations were moderate to weak. Based on the inhalable aerosol levels reported previously for the same workers, the observed urinary Cu concentrations were considerably lower than expected, relative to Co and Ni. This is interpreted in terms of the current understanding of Cu homeostasis.  相似文献   
6.
This perspective paper argues for an urgent need to monitor a set of 12 concrete, measurable indicators of food and water security in the Arctic over time. Such a quantitative indicator approach may be viewed as representing a reductionist rather than a holistic perspective, but is nevertheless necessary for actually knowing what reality aspects to monitor in order to accurately understand, quantify, and be able to project critical changes to food and water security of both indigenous and non-indigenous people in the Arctic. More relevant indicators may be developed in the future, taking us further toward reconciliation between reductionist and holistic approaches to change assessment and understanding. However, the potential of such further development to improved holistic change assessment is not an argument not to urgently start to monitor and quantify the changes in food and water security indicators that are immediately available and adequate for the Arctic context.  相似文献   
7.
8.
The spent nuclear fuel (SNF) and radioactive waste (RAW) storage facility at Andreeva Bay shore technical base (STB) is one of the largest and most hazardous nuclear legacy sites in northwest Russia. Originally commissioned in the 1960s the facility now stores large amounts of SNF and RAW associated with the Russian Northern Fleet of nuclear powered submarines. The objective of the present study was to map ambient gamma dose rates throughout the facility, in particular at a number of specific sites where SNF and RAW are stored. The data presented here are taken from a Norwegian-Russian collaboration enabling the first publication in the scientific literature of the complete survey of on-site dose rates. Results indicate that elevated gamma dose rates are found primarily at discrete sites within the facility; maximum dose rates of up to 1000 microSv/h close to the ground (0.1m) and up to 3000 microSv/h at 1m above ground were recorded, higher doses at the 1m height being indicative primarily of the presence of contaminated equipment as opposed to ground contamination. Highest dose rates were measured at sites located in the immediate vicinity of buildings used for storing SNF and sites associated with storage of solid and liquid radioactive wastes. Elevated dose rates were also observed near the former channel of a small brook that became heavily contaminated as a result of radioactive leaks from the SNF storage at Building 5 starting in 1982. Isolated patches of elevated dose rates were also observed throughout the STB. A second paper detailing the radioactive soil contamination at the site is published in this issue of Journal of Environmental Radioactivity.  相似文献   
9.
Petroleum exploration and production in the Barents Sea is a controversial topic. The Goliat field outside the northern coast of Norway will be the first offshore oil development in this region, with planned production start in 2013–2014. Avoiding major accidents at Goliat is critical; not only to reduce the risks to human lives and the environment, but also to gain political acceptance. Providing early warnings of major accidents for Goliat is one of the main objectives of the research project ‘Building Safety’. The objective of this paper is to describe the development of early warnings in the form of indicators. In addition, the paper includes an overview of current status of early warnings of accidents in other major hazard industries; the nuclear power industry, the chemical process industry, and aviation. Experiences from these industries, including lessons learned from recent major accidents, have been used as important input to the development of early warning indicators.  相似文献   
10.
Substantial emission of ammonia (NH3) from animal houses and the related high local deposition of NH3-N are a threat to semi-natural nitrogen-deficient ecosystems situated near the NH3 source. In Denmark, there are regulations limiting the level of NH3 emission from livestock houses near N-deficient ecosystems that are likely to change due to nitrogen (N) enrichment caused by NH3 deposition. The models used for assessing NH3 emission from livestock production, therefore, need to be precise, as the regulation will affect both the nature of the ecosystem and the economy of the farmer. Therefore a study was carried out with the objective of validating the Danish model used to monitor NH3 transport, dispersion and deposition from and in the neighbourhood of a chicken farm. In the study we measured NH3 emission with standard flux measuring methods, NH3 concentrations at increasing distances from the chicken houses using passive diffusion samplers and deposition using 15N-enriched biomonitors and field plot studies. The dispersion and deposition of NH3 were modelled using the Danish OML-DEP model. It was also shown that model calculations clearly reflect the measured NH3 concentration and N deposition. Deposition of N measured by biomonitors clearly reflected the variation in NH3 concentrations and showed that deposition was not significantly different from zero (P < 0.05) at distances greater than 150–200 m from these chicken houses. Calculations confirmed this, as calculated N deposition 320 m away from the chicken farm was only marginally affected by the NH3 emission from the farm. There was agreement between calculated and measured deposition showing that the model gives true estimates of the deposition in the neighbourhood of a livestock house emitting NH3.  相似文献   
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