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Even large inflows of oxygen-rich seawater to the Baltic Proper have in recent decades given only short-lived relief from oxygen deficiency below the halocline. We analyse long-term changes in oxygen deficiency, and calculate the “total oxygen debt” OD, the oxygen required to oxidize the hydrogen sulphide (H2S) and ammonium (NH4) that builds up during stagnation periods. Since the early 1990s, oxygen below 65m has gradually decreased during successive stagnation periods, and the OD has increased, with NH4 more important than previously recognised. After the major inflow in 2014, the Baltic Proper OD has reached its highest level so far. The gradual shift of the OD to shallower sub-halocline waters in the western and northern basins has increased the risk of periodic coastal hypoxia and export of hypoxic water to the Bothnian Sea. The potential for inflows large enough to more than eliminate the OD seems limited in the near term.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-022-01738-8. 相似文献
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Agneta Andersson H. E. Markus Meier Matyas Ripszam Owen Rowe Johan Wikner Peter Haglund Kari Eilola Catherine Legrand Daniela Figueroa Joanna Paczkowska Elin Lindehoff Mats Tysklind Ragnar Elmgren 《Ambio》2015,44(3):345-356
Climate change is likely to have large effects on the Baltic Sea ecosystem. Simulations indicate 2–4 °C warming and 50–80 % decrease in ice cover by 2100. Precipitation may increase ~30 % in the north, causing increased land runoff of allochthonous organic matter (AOM) and organic pollutants and decreased salinity. Coupled physical–biogeochemical models indicate that, in the south, bottom-water anoxia may spread, reducing cod recruitment and increasing sediment phosphorus release, thus promoting cyanobacterial blooms. In the north, heterotrophic bacteria will be favored by AOM, while phytoplankton production may be reduced. Extra trophic levels in the food web may increase energy losses and consequently reduce fish production. Future management of the Baltic Sea must consider the effects of climate change on the ecosystem dynamics and functions, as well as the effects of anthropogenic nutrient and pollutant load. Monitoring should have a holistic approach, encompassing both autotrophic (phytoplankton) and heterotrophic (e.g., bacterial) processes. 相似文献
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Mould in buildings constitutes a threat to health. Present methods to determine the moulds comprise counting of spores or determination of viable moulds which give imprecise measures of total mould cell biomass. Analysis of ergosterol and β-glucan as markers of mould cell biomass is expensive and cumbersome. To evaluate if airborne enzyme activity was related to mould in buildings air samples were taken using an impinger technique or cellulose filters in 386 rooms in 141 buildings. The samples were analysed for the activity of N-acetylhexosaminidase (NAHA) and expressed as enzyme units per m(3) (EU per m(3)). The highest value found in a building was used for the classification of the building and was related to the results from the subsequent technical inspection. In buildings without mould damage, the NAHA activity was generally below 20 EU per m(3). In buildings with mould damage, almost all the buildings had activities above 20 EU per m(3) (specificity 85%). At 30 EU per m(3) the specificity was 100%. Measurements of airborne enzyme activity have a high sensitivity and specificity to identify buildings with mould problems. The method can be used in the investigations of building related symptoms or for home exposure characteristics when investigating diseases such as asthma that can be related to mould exposure. 相似文献
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The paper reviews scientific studies of the past two decades dealing with the effects of advances in production technology on industrial injuries. The main features of these studies and the evidence gathered with regard to injury frequency, severity and characteristics are described. The accident co-determinants pointed to by the studies are highlighted. Methodological and theoretical shortcomings are discussed, and a research agenda comprising five questions is proposed. The fairest conclusion at this stage is that technological change may have positive effects with regard to injury occurrence and also promote personal well-being. But the conditions and moderating factors enabling favorable outcomes are not yet fully understood. 相似文献
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Trine Eggen Eldbjørg S. Heimstad Arne O. Stuanes Hans Ragnar Norli 《Environmental science and pollution research international》2013,20(7):4520-4531
Emerging contaminants in wastewater and sewage sludge spread on agricultural soil can be transferred to the human food web directly by uptake into food crops or indirectly following uptake into forage crops. This study determined uptake and translocation of the organophosphates tris(1-chloro-2-propyl) phosphate (TCPP) (log K ow 2.59), triethyl-chloro-phosphate (TCEP) (log K ow 1.44), tributyl phosphate (TBP) (log K ow 4.0), the insect repellent N,N-diethyl toluamide (DEET) (log K ow 2.18) and the plasticiser N-butyl benzenesulfonamide (NBBS) (log K ow 2.31) in barley, wheat, oilseed rape, meadow fescue and four cultivars of carrot. All species were grown in pots of agricultural soil, freshly amended contaminants in the range of 0.6–1.0 mg/kg dry weight, in the greenhouse. The bioconcentration factors for root (RCF), leaf (LCF) and seed (SCF) were calculated as plant concentration in root, leaf or seed over measured initial soil concentration, both in dry weight. The chlorinated flame retardants (TCEP and TCPP) displayed the highest bioconcentration factors for leaf and seed but did not show the same pattern for all crop species tested. For TCEP, which has been phased out due to toxicity but is still found in sewage sludge and wastewater, LCF was 3.9 in meadow fescue and 42.3 in carrot. For TCPP, which has replaced TCEP in many products and also occurs in higher residual levels in sewage sludge and wastewater, LCF was high for meadow fescue and carrot (25.9 and 17.5, respectively). For the four cultivars of carrot tested, the RCF range for TCPP and TCEP was 10–20 and 1.7–4.6, respectively. TCPP was detected in all three types of seeds tested (SCF, 0.015–0.110). Despite that DEET and NBBS have log K ow in same range as TCPP and TCEP, generally lower bioconcentration factors were measured. Based on the high translocation of TCPP and TCEP to leaves, especially TCPP, into meadow fescue (a forage crop for livestock animals), ongoing risk assessments should be conducted to investigate the potential effects of these compounds in the food web. 相似文献
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Vera L. G. Blank Lucie Laflamme Finn Diderichsen Ragnar Andersson 《Journal of Safety Research》1998,29(4):263-273
This study is concerned with the longitudinal representation of injury risk obtained using alternative injury-rate denominators—hours worked and production volume. It investigates injury risks at the underground extraction phase in a Swedish iron-ore mine. Six stages of mining development are defined, and three risk measures are employed: average injury rates (AIRs) by stage, injury rate ratios (IRRs) by stage, and annual injury rates (AnIRs). The two denominators give a quite different representation of injury risk at the early stages of the development of the mine, but tend increasingly to provide a similar picture (similar ratios) at later stages. It is concluded that automated production processes, as opposed to mechanized ones, tend to make hours worked and production volume interchangeable denominators. Choice of appropriate denominator may depend upon whether the individual or the production process is in focus. 相似文献
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PROBLEM: Suicide is a dominating, although hidden, safety problem on Swedish railroads. The aim of this paper is to describe the epidemiology of fatal train-person collisions as a basis for systems-oriented prevention. METHOD: Data on collision circumstances were collected from narrative reports at the Swedish National Rail Administration. RESULTS: The events were evenly distributed by months and weekdays, however, most suicides occur during the day while unintentional events usually occur at night. Most train-person collisions happened in densely populated areas, and 75% of the suicide victims were waiting on the track before the collision. Significance test between types of injury event (suicide, accident, or unknown intent) showed small or no differences. CONCLUSION: Traditional approaches to accident prevention by systems modification seem largely applicable to combat railroad suicide as well. IMPACT ON INDUSTRY: Our findings show promising preventive potentials. 相似文献
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Health Impact of Injuries: A Population-Based Epidemiological Investigation in a Local Community of Bangladesh 总被引:1,自引:0,他引:1
Due to the lack of valid injury data, the objective of this study was to assess the injury morbidity and mortality in a local community of Bangladesh. A population-based survey of 3,258 households was conducted in 1996. The information was collected by trained field-level health workers using three pretested structured forms. The estimated crude morbidity from injuries was 311 per 1,000 population per year, and injury accounted for 13% of all morbidity. The children and old-age groups experienced higher injury rates than others, and male children aged 5–15 years had the highest incidence rates (546/1,000 person-years). Falls and cutting injuries tended to be the most frequently (62.4%) observed types of injuries in this survey. The home (42%) and workplace (42%) were where most of the injuries occurred, and the majority (70.7%) of the injuries were minor. Of all deaths, mortality from injuries was 2.9%, and drowning (27.8%) and homicide (16.7%) were found as common forms of injury-causing deaths. This study invites more detailed investigation on injury morbidity and mortality. 相似文献