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The paper compares PM10 concentrations in railroad environments with EU air quality standards and characterizes particle concentrations and particle properties in relation to train traffic. The results show that PM10 concentrations in ground-level railroad environments do not exceed the EU directive 24-h limit value, while on the platforms of the two subterranean stations PM10 concentrations were far above the outdoor limit value. Diurnal and weekly patterns in PM10 concentration could be identified, co-varying with train traffic intensity. The particle mass size distribution peaked at around 2-6 μm. The elemental composition of PM10 at the subterranean stations was dominated by Fe.  相似文献   
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The paper is concerned incorporating landscapes’ ecological and cultural values in infrastructure planning. We focus on cultural heritage connectivity in the context of environmental impact statements in transportation infrastructure planning. Using a case study from south-central Sweden cultural heritage indicators from maps were defined, and a GIS-based automated search tool is developed for analysing cultural heritage connectivity from an antiquarian perspective. Analyses of cultural heritage connectivity can inform about the historical and/or present function of the landscape and its social and economic conditions. While this type of connectivity can be searched out using information from maps, a difficulty lies in communicating the knowledge in an interesting way to non-experts.  相似文献   
3.
This study investigates accident fatalities involving two types of off-road vehicles: snowmobiles and all-terrain vehicles (ATVs). All snowmobile fatalities in Sweden from the 2006/2007 season through the 2011/2012 season, and all ATV fatalities from 2007 through 2012, were retrospectively examined. A total of 107 fatalities—57 snowmobile-related and 50 ATV-related—were found. Most deaths occurred on weekends (71% of the snowmobile-related and 72% of the ATV-related). A majority of the fatalities were males (91% and 94%), with the largest share in the age group 40–49 years (19% and 24%). The most common causes of death were blunt trauma (56% and 66%), drowning (30% vs 6%), and traumatic asphyxia (9% vs 14%). Among victims who were tested (95% vs 92%), a very high share was found to be inebriated (59% vs 61%), and mean blood alcohol concentration was also high (1.9 vs 1.7 g/l). Forty-seven percent of snowmobile-related fatalities and 48% of ATV-related fatalities had a blood alcohol concentration above 1.0 g/l. This means that there was a very strong association between off-road vehicle fatalities and drunken riding; steps to prevent riding while intoxicated seem to be the most important preventive measure. Automatic measures such as alcolocks are probably the most effective. The obvious at-risk group to target is middle-aged men with high alcohol consumption.  相似文献   
4.
The deep Gullmar Fjord on the Swedish west coast may be subject to a trend of decreasing oxygen content of the bottom-water. Due to a non-uniform frequency of oxygen measurements before and after 1980, and small differences in the minimum concentrations, it is difficult to assess with certainty if this is true or not. We have used benthic foraminifera from three ultra-high resolution sediment records to try to find out if such a trend exists. The sediment records comprise the time between 1930 and 1996, with an almost year-based temporal resolution. The foraminiferal records show a significant change in faunal composition during the mid-1970's when it altered from a common Skagerrak fauna to an assemblage characterized by an opportunistic, low oxygen tolerant species; Stainforthia fusiformis. This species is an indicator of low oxygen environments of many Scandinavian fjords. The timing of this faunal change coincides with one of the first recorded severe low oxygen events in the Gullmar Fjord in the winter of 1973/1974. The change suggests that the Gullmar Fjord has actually been subject to a decrease in bottom-water oxygen concentrations. The reason for this change is not clear but here, for the first time, we present sediment records that suggest that there is a causal relation between variations in the North Atlantic Oscillation (NAO) indices and the marine environment. In the early 1970s the NAO-indices altered from a mainly negative phase towards a mainly positive period which is still ongoing. Positive NAO-indices (winter values) in the Skagerrak region are generally marked by westerly winds which normally prevent the exchange of bottom-water in the fjords, i.e., the oxygenation of the sea floor and the supply of oxygen to benthic life.  相似文献   
5.
The transition zone between the North Sea and the Baltic Sea is a highly dynamic region where a general estuarine circulation forms a regional scale frontal system from northern Kattegat to the Arkona Sea. This system is characterized by an upper low saline out?owing Baltic water mass from the in?owing saline Skagerrak bottom water to the Kattegat and Belt Sea area. Large and rapid ?uctuations of the frontal system are caused by barotropic transports, forced by changing sea level difference between northern Kattegat and the western Baltic Sea, and this results in high variability of the hydrographic conditions and also in frequent in- and out?ow events to the Baltic. The dynamics in the region are here analyzed by a regional model of the transition zone, covering the area from the northern Kattegat to the Arkona Sea. The model is validated against water level, temperature and salinity measurements from the region, and the transports through the Danish straits are related to previous estimates and empirical relations. A sensitivity study quantify the role of bathymetry, the tidally induced mixing and the in?owing Skagerrak bottom water for ventilating the bottom water with Skagerrak water or surface water.Furthermore, the dynamics in the region is analyzed with tracers representing the age of the water. The distribution of age tracers with different boundary conditions are analyzed, and the role of advection and mixing for ventilating the bottom water is quanti?ed in terms of the water age. It is shown that the Great Belt area is a very dynamical area where bottom water is ventilated with surface water. The interannual variation of the ventilation of bottom water in the period 2001–2003 is analyzed by various age tracers and related to observed oxygen conditions, and it is shown that the extreme hypoxic event in the autumn 2002 in the southern Kattegat, the Great Belt and in the western Baltic Sea coincide with an unusual low vertical ventilation rate in the Great Belt area, but normal advection rates of bottom water from the northern Kattegat. This indicates that during this particular event, and probably in general, ventilation of bottom water in the Great Belt has signi?cant in?uence on oxygen conditions in the southern part of the region and for ventilation of bottom waters in the western Baltic Sea. In contrast, the central Kattegat is primarily ventilated by advection of bottom water from the Skagerrak. An age tracer representing the ventilation rate of bottom water with either Skagerrak water or surface water is shown to be inversely correlated to the observed oxygen distribution in the region.  相似文献   
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