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21.
Kowalik P  Laakkonen S 《Ambio》2007,36(2-3):220-228
The postwar development of water protection legislation and wastewater discharges is poorly known for the Baltic Sea region as a whole. This article presents national efforts to govern wastewater discharges in Poland using legal tools over the twentieth century with an emphasis on the postwar period, 1945-2003. The study also attempts to evaluate how the state authority responded to changing legal demands in terms of urban and industrial wastewater discharges in the postwar period. It outlines the main changes during the socialist regime in Poland and after it regained independence. Also the implications of Poland's integration into the European Union are briefly discussed. Mathematical calculations are used to illustrate some changes in legal requirements over time.  相似文献   
22.
Recent survey results for polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs, dioxins) in Baltic Sea sediments from Finland, Sweden and Denmark were merged with previously published Baltic Sea data. Regional distribution of concentration levels, differences in congener patterns, and temporal changes in sediment profiles were examined. One of the main objectives was to study if any major point sources for different PCDD/F congeners could be identified on a regional scale, based on sediment records. The survey confirmed the impact of chlorophenol production derived highly chlorinated PCDF-congeners on the total toxicity in sediments in the Gulf of Finland near the Kymijoki river estuary. Signatures of other point sources or combined point sources pertinent to specific industry branches or particular production processes (such as pulp bleaching, vinyl chloride production, thermal processes) may be discerned. However, the findings did not support any of the known point sources significantly influencing those congeners that are most abundant in Baltic herring and salmon. Instead, regional distributions in the Baltic Sea indicate that atmospheric deposition may act as a major source for those congeners and especially for 2,3,4,7,8-PeCDF. There were clear indications of declines in levels in sediment in some areas, but generally the levels of highly chlorinated PCDD/Fs on the northern coast of the Gulf of Finland were still high when compared with other areas of the Baltic Sea. Major areas with data gaps cover the south-eastern and eastern coastal regions of the Baltic Proper and the southern Gulf of Finland.  相似文献   
23.
Lynch  Amanda H.  Griggs  David  Joachim  Lee  Salminen  Ed  Heider  Chris  Kestin  Tahl  Zhu  Xuan  Veland  Siri 《Regional Environmental Change》2017,17(3):767-776
Regional Environmental Change - Geographic information systems are a means to develop a common framework for the integration of a range of perspectives into natural resources management decisions....  相似文献   
24.
The iron content was studied in the epiphytic lichens Hypogymnia physodes (L.) Nyl. and Pseudevernia furfuracea (L.) Zopf, in the terricolous lichens Cladina sp. and Peltigera aphthosa (L.) Willd., and in pine bark collected from 31 sites in Finland. There appeared to be differences between lichen species, epiphytes having generally higher concentrations. The iron content of H. physodes was highly significantly correlated (p<0.001) with its sulphur content, reflecting the relations of these elements in precipitation. The highly significant correlations between the iron and titanium contents indicated differences of the phorophytes. The iron/sulphur ratio of H. physodes on pine was 1.3 and on birch 1.4 and iron/titanium ratios were 10.4 and 11.3 respectively. The iron content of Cladina sp. showed highly significant parallel correlations (p<0.001) with its sulphur and titanium contents. The iron/titanium ratio decreased from 9.6 to 8.2 when the iron content increased by 95%, the sulphur content being equal. The iron/titanium ratio of Cladina sp. was nearly identical to that of P. furfuracea. The relation between iron and sulphur, and the fraction of soluble and insoluble iron in precipitation versus lichens and pine bark were considered. Special attention was paid in the discussion to differences in substrate: pine and birch bark for H. physodes, and soil for Cladina sp.  相似文献   
25.
The occurrence and rates of terminal electron acceptor processes, and recharge processes in the unsaturated zone of a boreal site contaminated with petroleum hydrocarbons in the range C(10) to C(40) were examined. Soil microcosms were used to determine the rates of denitrification, iron (Fe) reduction, sulfate (SO(4)) reduction, and methanogenesis in two vertical soil profiles contaminated with oil, and in a noncontaminated reference sample. Furthermore, the abundances of the 16S rRNA genes belonging to Geobacteracaea in the samples were determined by real-time quantitative polymerase chain reaction (PCR). Analyses of ground water chemistry and soil gas composition were also performed together with continuous in situ monitoring of soil water and ground water chemistry. Several lines of evidence were obtained to demonstrate that both Fe reduction and methanogenesis played significant roles in the vertical profiles: Fe reduction rates up to 3.7 nmol h(-1) g(-1) were recorded and they correlated with the abundances of the Geobacteracaea 16S rRNA genes (range: 2.3 x 10(5) to 4.9 x 10(7) copies g(-1)). In the ground water, ferrous iron (Fe(2+)) concentration up to 55 mg L(-1) was measured. Methane production rates up to 2.5 nmol h(-1) g(-1) were obtained together with methane content up to 15% (vol/vol) in the soil gas. The continuous monitoring of soil water and ground water chemistry, microcosm experiments, and soil gas monitoring together demonstrated that the high microbial activity in the unsaturated zone resulted in rapid removal of oxygen from the infiltrating recharge thus leaving the anaerobic microbial processes dominant below 1.5 m depth both in the unsaturated and the saturated zones of the subsurface.  相似文献   
26.
Sediment trap material was collected during May–December in the period 1996–2008 in three coastal areas and four open sea stations in the Finnish territory of the Baltic Sea. The highest sedimentation of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) with a typical source-related congener profile from chlorophenol production dominated by highly chlorinated dibenzofurans was found close to a historical source in the Kymijoki estuary. This was an order of magnitude higher than in other river estuaries and two orders of magnitude higher than in the open sea stations. The sedimentation of polychlorinated biphenyls (PCBs) was also higher in river estuaries than in other areas. No significant decrease over a 12 year period of monitoring was found in concentration or in sedimentation in the Kymijoki estuary. In the western Gulf of Finland, the Archipelago Sea and the Gulf of Bothnia, the dominating congeners, calculated as toxic equivalent (TEQ) in sedimentation were 1, 2, 3, 7, 8-PeCDD and 2, 3, 4, 7, 8-PeCDF, often reported as the main congeners in deposition.  相似文献   
27.
Räsänen T  Laakkonen S 《Ambio》2007,36(2-3):229-236
The Convention on the Protection of the Marine Environment of the Baltic Sea Area signed in 1974 in Helsinki is probably the most important environmental agreement consummated in the Baltic Sea region. This article is the first study that explores the history of this agreement, also known as the Helsinki Convention, by using primary archival sources. The principal sources are the archives of the Ministry for Foreign Affairs of Finland. We examine the role of Finland in the process that led to the signing of the Helsinki Convention from the perspective of international politics. The study focuses primarily on Finnish, Swedish, and Soviet state-level parties from the end of the 1960s to 1974. We show that Cold War politics affected in several ways negotiations and contents of the Helsinki Convention. We also argue that the Soviet Union used the emerging international environmental issues as a new tool of power politics.  相似文献   
28.
The aim of this study was to discover accident factors specific to young workers, using two accident data sets gathered at the same time but with different methods. The first data set consisted of 99 serious occupational accidents, which occured in Southern Finland in 1988 and 1989. The second data set was based on the interview study of over 13,000 people of whom 792 were involved in an accident at work. Both data sets showed consistently that the accident frequency of young workers was higher than that of older workers. The accidents of young workers, however, were less severe. Young accident victims hurt themselves more often when feeding or cleaning machines. Incautiousness contributed more often to accidents of young workers. In order to prevent occupational accidents of young workers, companies should introduce training programmes for new employees.  相似文献   
29.
Degradation of potassium formate in the unsaturated zone of a sandy aquifer   总被引:1,自引:0,他引:1  
This paper presents results from a lysimeter experiment on the fate of potassium formate, an alternative deicing agent. The experiment was performed through the winter and spring to identify any thermal sensitivity in the transport and biodegradation of formate in the lysimeter. Ninety-eight percent of the total quantity of formate applied was degraded while percolating through the 1.7-m-thick unsaturated sand layer within the lysimeter. Concomitantly, the bicarbonate concentration of the percolating water increased. The low concentrations of nitrogen (0.02 mg L(-1)) and phosphorous (<0.002 mg L(-1)) in the percolated water, however, potentially limited microbial activity. During the study period, 99% of the applied potassium was retained in the lysimeter, and the ion exchange between the potassium and a variety of monovalent and divalent ions was assumed to be responsible for the leaching of barium, calcium, magnesium, and sodium from the soil material. Except for manganese, the concentrations of the studied metals in the percolated water did not exceed the threshold values set for drinking water by the Council of the European Union. By contrast, the application of potassium formate had a detrimental effect on the vegetation on the lysimeter. To conclude, formate was effectively degraded in the sandy lysimeter and its application did not cause major undesirable changes in the quality of the percolating water. Further research at field scale is, however, needed for instance on the biodegradation of potassium formate and on its impacts on roadside vegetation.  相似文献   
30.
Summary. We investigated the effects of four chemically characterised galloylglucoses (GGs, a subgroup of hydrolysable tannins) and their hydrolysis product, gallic acid (GA), on consumption and performance of larvae of the autumnal moth Epirrita autumnata. Larvae were fed with birch (Betula pubescens) leaves that had been painted individually with each of the compounds at two levels, 5 and 20 mg/g. In addition, we investigated the fates of the leaf-painted GGs and GA in the E. autumnata digestive tract by comparing phenolics in leaves consumed and in faeces. In general, GGs reduced leaf consumption by E. autumnata during the second and fourth instars, although there was high compound- and instar-specific variation. However, GGs did not affect the leaf consumption rates by the most voracious fifth instar larvae. This resulted in approximately the same loss of total biomass by the experimental tree, regardless of the nature and level of GGs enriched to its foliage. The characteristic fate of hydrolysable tannins, i.e. hydrolysis, was evidenced in the larval digestive tract for three of the four leaf-painted GGs. In addition to hydrolysis, the almost total absence of GGs in larval faeces was presumably related to the oxidation of GGs. The dose-dependent excretion percentage of ingested GA showed that it's faecal content should not be used, although it commonly is, to calculate the level of GG hydrolysis. Moreover, by comparing the non-uniform appearance of faecal tetragalloylglucoses, whether ingested as such or hydrolysed from pentagalloylglucose, we concluded that a major part of oxidation of GGs occurs before their hydrolysis in the digestive tract of E. autumnata. Criticism against the common use of tannic acid, a heterogeneous mixture of GA and GGs, in ecological studies is presented. Received 15 May 2002; accepted 16 July 2002  相似文献   
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