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551.
552.
This paper is concerned with the normative underpinnings of popular sustainability indicators and country rankings. Attempts to quantify national sustainability in the form of composite indicators and rankings have increased rapidly over past decades. However, questions regarding validity and interpretability remain. This article combines theoretical and statistical tools to explore how input variables in five popular sustainability indicators can be related to different theoretical paradigms: weak and strong sustainability. It is shown that differences in theoretical interpretations affect input variable selection, which in turn affects indicator output. This points towards the risk of indicators becoming a sort of ‘circular argumentation construct’. The article argues that sustainability indicators and country rankings must be treated as theoretical just as much as statistical instruments. It is proposed that making underlying normative assumptions explicit, and making input variable selection more clear in a theoretical sense, can enhance indicator validity and usability for policy makers and researchers alike.  相似文献   
553.
The quality of sewage sludge-based products, such as composts and growth media, is affected by the contamination of sewage sludge with, potentially, hundreds of different substances. Therefore, it is difficult to achieve the reliable environmental quality assessment of sewage sludge-based products solely based on chemical analysis. In the present work, we demonstrate the use of the kinetic luminescent bacteria test (ISO 21338) to evaluate acute toxicity and the Vitotox? test to monitor genotoxicity of sewage sludge and composted sewages sludge. In addition, endocrine-disrupting and dioxin-like activity was studied using yeast-cell-based assays. The relative contribution of industrial waste water treated at the Waste Water Treatment Plants led to elevated concentrations of polyaromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and polychlorinated dibenzo-p-dioxins and -furans (PCDD/F) in sewage sludge. The effect of elevated amounts of organic contaminants could also be identified with biotests able to demonstrate higher acute toxicity, genotoxicity, and potential for endocrine-disruptive properties. Additional extraction steps in kinetic luminescent bacteria test with DMSO and hexane increased the level of toxicity detected. Composting in a pilot-scale efficiently reduced the amounts of linear alkylbenzensulphonates (LASs), nonylphenols and nonylphenolethoxylates (NPE/NPs) and PAH with relative removal efficiencies of 84%, 61% and 56%. In addition, decrease in acute toxicity, genotoxicity and endocrorine-disrupting and dioxin-like activity during composting could be detected. However, the biotests did have limitations in accessing the ecotoxicity of test media rich with organic matter, such as sewage sludge and compost, and effects of sample characteristics on biotest organisms must be acknowledged. The compost matrix itself, however, which contained a high amount of nutrients, bark, and peat, reduced the sensitivity of the genotoxicity tests and yeast bioreporter assays.  相似文献   
554.
The farming community is today faced with requests by various interest groups to implement environmental management systems (EMS). The series of items shows principle theoretical questions of the method and the advantages of EMS (part I and II), presents the practical outcome (part III) and give a recommendation for potential users of EMS in agricultural systems (part IV). The study conducted outlines the method of the implementing an EMS according to the Environmental Management and Audit System (EMAS) and ISO 14001. Further advantages and disadvantages for the agricultural industry are addressed. Even though terms such as site can not easily be defined or problems with open material cycles and structural particularity of agricultural farms there appears to be a benefit to implement. The transparency and documentation of the material flow as well as the economical benefits of an optimized organization count towards the EMS. Further EMS can be a means to strengthen the argumentative position for example with the public, authorities, banks or insurance. This concurs with minimizing company liabilities and obtaining governmental privileges (deregulation).  相似文献   
555.
The Baltic Sea runoff events during 1970–2000 were analysed with non-linear estimation in order to find potential stability and time-varying (non-constancy) properties of time series parameters. In the Baltic Sea area, the wintertime rainfall is expected to increase, especially in the northern parts of the watershed; furthermore, seasonality is expected to decrease, i.e. the runoffs will become more evenly distributed over seasons, mainly by decreasing springtime peaks. We found a general increase in runoffs over the time period studied that consisted of a level shift upwards during the early 1980s. The runoffs considerably resulted from inputs in the months of April to June (which points to the significance of winter precipitation) and are biased to northern parts of the catchment. Our results suggest that this is connected with snow and ice melting in the northern areas of the watershed, especially in the subarctic catchment area of the Neva River (the area includes, for example, three of the four biggest lakes in Europe, Lake Ladoga, Lake Onega and Lake Saimaa, which are annually covered by ice). The yearly variation in runoff is significantly stabilised by large N–S extension of the watersheds of these lakes. The results are generally in accordance with the presented climatic expectations; however, decreasing seasonality was not obvious in the series yet. However, we found potential implications of system change towards decreased seasonality. By better understanding of ongoing processes in the sea, the results can give us an opportunity to better evaluate the system control, predicted areal consequences and ecosystem effects of the climate change. The analysis proved to be a sensitive tool for studying climatic variation in a relatively small area and over a short time span.  相似文献   
556.
The fate of 14C-labeled difloxacin (14C-DIF) was studied in time course experiments after application on soil (Ap horizon of silt loam) and amendment of authentic DIF containing pig manure (146 mL kg?1; 4.17 MBq kg?1; 0.85 mg kg?1) or water (124 mL kg?1; 0.42 MBq kg?1; 0.09 mg kg?1) for 56 and 120 days of incubation, respectively.

Mineralization of 14C-DIF was below 0.2% in both experiments after 56 days or 120 days. In the course of the experiments, portions of extractable radioactivity (Accelerated Solvent Extraction (ASE); acetonitrile-water) decreased to 19–21% depending only little on manure amendment. Non-extractable residues of 14C-DIF increased to 70–74% after 56 days and 120 days, respectively, and therefore were the main route of 14C-DIF in soil. According to radioanalytical HPLC and LC-MS/MS, only the parent compound was found in all extracts over the whole time of the experiment. According to fractionation of the non-extractable residues (NER) into particle size fractions, 14C portions were associated to the water used for fractionation, the silt and clay fractions, whereas no radioactivity was detected in the sand fraction. The majority of 14C was found within the clay fractions.

Fractionation of humic components showed that radioactivity derived from 14C-DIF was associated with humic acids, fulvic acids, humins and minerals and very little with soluble, non-humic HCl fraction. The highest portions of radioactivity were found in the fulvic acid fraction. Results obtained by size exclusion chromatography (SEC) of the purified fulvic acids were similar for every sample analyzed. One large portion of 14C co-eluted with fulvic acids of a molecular weight below 910 g mol?1. Both fractionation methods demonstrated that the parent compound DIF or initial metabolites were rapidly integrated into humic materials and, thus, were major components of NER.  相似文献   
557.
Perfluoroalkyl substances (PFASs) in food and water from Faroe Islands   总被引:1,自引:1,他引:0  
Diet and drinking water are suggested to be major exposure pathways for perfluoroalkyl substances (PFASs). In this study, food items and water from Faroe Islands sampled in 2011/2012 were analyzed for 11 perfluoroalkyl carboxylic acids (PFCAs) and 4 perfluoroalkane sulfonic acids (PFSAs). The food samples included milk, yoghurt, crème fraiche, potatoes, fish, and fish feed, and the water samples included surface water and purified drinking water. In total, nine PFCAs and four PFSAs were detected. Generally, the levels of PFAS were in the lower picogram per gram range. Perfluorobutanoic acid was a major contributor to the total PFASs concentration in water samples and had a mean concentration of 750 pg/L. Perfluoroundecanoic acid (PFUnDA) was predominating in milk and wild fish with mean concentrations of 170 pg/g. Perfluorooctane sulfonic acid (PFOS) was most frequently detected in food items followed by PFUnDA, perfluorononanoic acid, and perfluorooctanoic acid (PFOA). Levels of PFUnDA and PFOA exceeded those of PFOS in milk and fish samples. Prevalence of long-chain PFCAs in Faroese food items and water is confirming earlier observations of their increase in Arctic biota. Predominance of short-chain and long-chain homologues indicates exposure from PFOS and PFOA replacement compounds.  相似文献   
558.
559.
There are worldwide approximately 4.3 million coffee (Coffea arabica) producing smallholders generating a large share of tropical developing countries’ gross domestic product, notably in Central America. Their livelihoods and coffee production are facing major challenges due to projected climate change, requiring adaptation decisions that may range from changes in management practices to changes in crops or migration. Since management practices such as shade use and reforestation influence both climate vulnerability and carbon stocks in coffee, there may be synergies between climate change adaptation and mitigation that could make it advantageous to jointly pursue both objectives. In some cases, carbon accounting for mitigation actions might even be used to incentivize and subsidize adaptation actions. To assess potential synergies between climate change mitigation and adaptation in smallholder coffee production systems, we quantified (i) the potential of changes in coffee production and processing practices as well as other livelihood activities to reduce net greenhouse gas emissions, (ii) coffee farmers’ climate change vulnerability and need for adaptation, including the possibility of carbon markets subsidizing adaptation. We worked with smallholder organic coffee farmers in Northern Nicaragua, using workshops, interviews, farm visits and the Cool Farm Tool software to calculate greenhouse gas balances of coffee farms. From the 12 activities found to be relevant for adaptation, two showed strong and five showed modest synergies with mitigation. Afforestation of degraded areas with coffee agroforestry systems and boundary tree plantings resulted in the highest synergies between adaptation and mitigation. Financing possibilities for joint adaptation-mitigation activities could arise through carbon offsetting, carbon insetting, and carbon footprint reductions. Non-monetary benefits such as technical assistance and capacity building could be effective in promoting such synergies at low transaction costs.  相似文献   
560.
OBJECTIVE: The study evaluated the accident risk of certain driving circumstances and driving motives among novice drivers. METHODS: Self-reported exposure and accidents according to driving circumstances and driving motives were compared between young (n = 6,847) and middle-aged (n = 942) male and female novice drivers. For young drivers, self-reported accidents were further compared to fatal accidents (n = 645) in terms of the driving conditions in which they occurred. The survey was conducted in 2002 and the questions regarding the quantity and quality of driving exposure and accidents covered the first four years of the novice drivers' driving career after licensing. Data on fatal accidents related to the period of 1990 to 2000. RESULTS: Leisure-time driving, driving just for fun, and driving with passengers and during evenings and at night was more typical for young drivers than for middle-aged drivers. For middle-aged drivers, the most typical driving was driving to or from work. Driving on errands was more typical for females than males. Nighttime driving was overrepresented in young drivers' self-reported and fatal accidents, compared to the share of young drivers' driving at night. Slippery road conditions were over-represented in young male drivers' self-reported accidents, but not in their fatal accidents, whereas for young females slippery road conditions seemed to increase the propensity of fatal accidents. CONCLUSIONS: The study concluded that some driving conditions increase the risk of certain types of accidents among certain driver groups, but not among all drivers. For example, slippery road conditions were overrepresented in young male drivers' minor (self-reported) accidents, but not in their fatal accidents. For young female drivers slippery road conditions seem to increase the propensity of fatal accidents. Driving circumstances are different in minor (self-reported) and fatal accidents. When drawing conclusions regarding accident risk, it is important to determine the seriousness of the accidents which take place.  相似文献   
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