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In Finland the number of potentially contaminated sites totals ca. 20?000. The annual costs of remediation are 60–70 million euros. Excavation combined with disposal or off-site treatment is the most common soil remediation method. To define which factors make contaminated land management (CLM) eco-efficient and to study whether eco-efficiency has been considered in CLM decisions we carried out a literature survey, two stakeholder seminars, thematic interviews and a questionnaire study on economic instruments. Generally speaking, eco-efficiency means gaining environmental benefits with fewer resources. To assess its realization in CLM, it is necessary to have a more specific definition. In our study, we arrived at a list of several qualifications for eco-efficiency. It was also shown that eco-efficiency has hardly been a real issue in the selection of remediation techniques or generally, in the decision-making concerning contaminated sites. The existing policy instruments seem to be insufficient to promote eco-efficiency in CLM. Several concrete barriers to eco-efficiency also came up, urgency and lack of money being the most important. The scarcity of the use of in situ remediation methods and the difficulties involved in recycling slightly contaminated or treated soil were considered to be major problems. Insufficient site studies, inadequate or unsuitable methods for risk assessment and cost evaluation, and deficient and mistimed risk communication can also hinder the realization of eco-efficiency. Hence, there is a need to promote the use of more eco-efficient remediation techniques and to develop CLM policy instruments, guidelines, and participatory processes and methods to assess the eco-efficiency of CLM options.  相似文献   
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A total of 156 fish composite samples were collected from five areas of the Baltic Sea and from three lakes and analysed for polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), polychlorinated biphenyls (PCBs), polychlorinated naphthalenes (PCNs) and polybrominated diphenyl ethers (PBDEs). The European Union's maximum permissible level for PCDD/Fs, 4 pg WHO-TEQ/g fresh weight (fw), was exceeded in salmon, river lamprey and Baltic herring. In other species from the Baltic Sea, the 90th percentile was 3.42 pg WHO(PCDD/F)-TEQ/g fw. In the lake fish, the concentrations of PCDD/Fs, PCBs and PCNs were only 29-46% of those in the same species caught from the Baltic Sea, whereas the concentrations of PBDEs in the lake fish were as high as in the Baltic Sea fish. Dioxin-like PCBs contributed to the total dioxin-like toxicity of PCBs and PCDD/Fs by 49+/-12% in all the analysed samples.  相似文献   
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Groundwater dependent ecosystems. Part I: Hydroecological status and trends   总被引:3,自引:0,他引:3  
Groundwater dependent ecosystems (GDEs) include valuable ecosystems such as springs, wetlands, rivers, lakes and lagoons. The protection of these systems and services they provide is highlighted by international agreements, i.e. Ramsar convention on wetlands, and regional legislation, i.e. the European Water Framework Directive. Groundwater provides water, nutrients and a relatively stable temperature. However, the role of groundwater in surface ecosystems is not fully understood. The ecosystem can depend on groundwater directly or indirectly, and the reliance can be continuous, seasonal or occasional. This has implications for the vulnerability of ecosystems, as some may be easily affected by external pressure. Conceptual models and quantitative assessments of how groundwater interacts with the environment are needed. GDEs are also threatened by different land use activities and climate change. Hence, we need to understand how GDEs are affected by changes in groundwater quantity and quality, as severe groundwater changes have been observed in many regions. This study examines key aspects of GDEs (hydrogeology, geochemistry and biodiversity) in order to improve conceptual understanding of the role of groundwater in such ecosystems. The status and baseline of different types of GDEs are discussed, with particular emphasis on past evidence of environmental change and potential thresholds and threats in GDEs in various parts of Europe with different land use, climate and geology.  相似文献   
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Employees' work outcomes vary as a function of their focus on exploring new possibilities versus exploiting current opportunities. But what determines how employees divide their attention between these contrasting work behaviors? Drawing on studies on work motivation and employees' impression management concerns, we examine how intrinsic work motivation and self‐enhancement motivation relate to the exploration–exploitation balance and how environmental dynamism moderates these relationships. Based on the analyses of a sample of 638 employees in 34 organizations in Finland, we find that intrinsic work motivation is positively associated with employees' focus on exploration relative to exploitation. By contrast, self‐enhancement motivation negatively associates with exploration relative to exploitation, but this relationship is nonlinear, such that as self‐enhancement motivation increases, its positive association with exploitation diminishes. The findings also show that the hypothesized nonlinear relationship between self‐enhancement motivation and exploration is particularly pronounced in stable business environments. Our findings contribute to organizational learning research and provide a new theoretical perspective on pursuing exploration and exploitation in organizations.  相似文献   
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IntroductionItisgenerallyassumedthatacidrain,biosphericozone,metalfalloutorsomeotherpollutantscauseforestdeclinethroughphytotoxemiaswhichshowspecificsymptomsofdisease.Ithasbeenshownexperimentallythatsuchdiseasesymptomsmayreallydevelopintreeswhentheya…  相似文献   
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Polychlorinated hydrocarbons and chlorophenol compounds were analyzed in three populations of Baltic salmon (Salmo salar) and one population of Bothnian Bay trout (Salmo trutta). Muscles, livers and unfertilized eggs were studied and the analysis results treated by standard statistical methods. PCB, DDT residues, HCB and lindan were detected in most, 2,3,6-t-richlorocymene in some samples at levels which are near to the global baseline. Ten chlorophenol compounds were detected, 34DCC at 0–1000 ug/kg the others 0–100 ug/kg (fresh weight) levels. Chlorohydrocarbons showed some significant positive correlations with weight, and fat contents of the fish. Significances of the differences between populations and tissues were low or neglible except that the chlorophenols in liver were at clearly higher level than in muscle or eggs.  相似文献   
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Tauno Kuokkanen  Pekka Autio 《Chemosphere》1989,18(9-10):1921-1925
p-Cymene was chlorinated by chlorine in CCl4. The products of the chlorination were separated by distillation and purified by preparative gas chromatography. The structures of chlorocompounds were confirmed by means of their NMR and mass spectra. The distillation gave as the main compounds: (2) 2-chloro-, (4) 2,3-dichloro-, (5) 2,5-dichloro-, (6) 2,3,6-trichloro-, (7) 2,3,5,6-tetrachloro-p-cymenes and as by-products: (8) 2,5,7-trichloro-p-cymene, (9) 2,6-dichloro-1-methyl-4-(1-methylethenyl)benzene (cymenene), and (10) 2,3,6-trichloro-1-methyl-4-(1-methylethenyl)benzene (cymenene).  相似文献   
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