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341.
This paper shows how different methods can be integrated in order to provide an organic evaluation of the environmental sustainability at the territorial level. A territory is a complex, dynamic and open system where a population develops, uses resources, produces goods and services, consumes, depletes and finally obtains economic results. All these elements characterise human behaviour, which can be monitored, measured and compared to the capacity of the environment to sustain it in the long run. The SPIn-Eco Project for the Province of Siena (Italy) is described as an example of an environmental sustainability assessment of an area, and its methods (Ecological Footprint, Greenhouse Gas Inventory, Extended Exergy Analysis, Emergy Evaluation, Life Cycle Assessment (LCA) and Remote Sensing) are briefly introduced. This Project has been proposed and funded by the most important provincial administrative and financial institutions in the territory (the Administration of the Province of Siena and the Monte dei Paschi Foundation, respectively), and was designed and realised in 4 years (2001-2004) by a research team coordinated by the University of Siena.  相似文献   
342.
An adaptive management approach is necessary but not sufficient to address the long-term challenges of the Greater Yellowstone Ecosystem (GYE). Adaptive management, in turn, has its own particular challenges, of which we focus on two: science input, and stakeholder engagement. In order to frame our discussion and subsequent recommendations, we place the current management difficulties into their historical context, with special emphasis on the 1990 Vision document, which attempted a broad synthesis of management goals for the ecosystem. After examining these two key challenges in the context of the GYE, we make several recommendations that would allow for more effective ecosystem management in the long term. First, we recommend adoption of the GYE as a site for long-term science research and monitoring with an emphasis on integrative research, long-term federal funding, and public dissemination of data. Second, we conclude that a clearer prioritization of legislative mandates would allow for more flexible ecosystem management in the GYE, a region where conflicting mandates have historically led to litigation antithetical to effective ecosystem management. Finally, we recommend a renewed attempt at an updated Vision for the Future that engages stakeholders (including local landholders) substantively from the outset.  相似文献   
343.
Köppen R  Becker R  Jung C  Nehls I 《Chemosphere》2008,71(4):656-662
The interconversion of the stereoisomers contained in technical 1,2,5,6,9,10-hexabromocyclododecane, a major brominated flame retardant increasingly found in the environment and in biota, was investigated at elevated temperatures. The application of pure enantiomers of the three constituents alpha-, beta-, and gamma-HBCD enabled the unambiguous elucidation of the individual isomerisation reactions as well as the quantification of all respective rate constants. At 160 degrees C the rate constants range over two orders of magnitude from 1.50x10(-3) to 1.88x10(-5)mol(%)s(-1). A preliminary mechanistic explanation for the differences of the rate constants which govern the composition of HBCD diastereomers at equilibrium is given.  相似文献   
344.
Niederer C  Goss KU 《Chemosphere》2008,71(4):697-702
Chlorophenol isomers are known to possess substantially different octanol/water and octane/water partition constants depending on whether the chlorine substituents are in the ortho or meta/para position. Here we show that the same is also true for environmental partition processes such as water/air and humic acid/air partitioning. Quantitative structure property relationships (QSPR) such as those in the widely used EPI-suite or SPARC fail to correctly predict this influence of the substituent position on the compound's partitioning. Only a more sophisticated quantum chemical software, called COSMOtherm, correctly reproduced these effects. Based on this and earlier experiences we conclude that COSMOtherm may be a better tool for screening large sets of chemicals for which no experimental data on their partitioning yet exist.  相似文献   
345.
A detailed analysis of indoor/outdoor physicochemical aerosol properties has been performed. Aerosol measurements were taken at two dwellings, one in the city center and the other in the suburbs of the Oslo metropolitan area, during summer/fall and winter/spring periods of 2002-2003. In this paper, emphasis is placed on the chemical characteristics (water-soluble ions and carbonaceous components) of fine (PM2.5) and coarse (PM2.5-10) particles and their indoor/outdoor relationship. Results demonstrate that the carbonaceous species were dominant in all fractions of the PM10 particles (cut off size: 0.09-11.31 microm) during all measurement periods, except winter 2003, when increased concentrations of water-soluble inorganic ions were predominant because of sea salt transport. The concentration of organic carbon was higher in the fine and coarse PM10 fractions indoors, whereas elemental carbon was higher indoors only in the coarse fraction. In regards to the carbonaceous species, local traffic and secondary organic aerosol formation were, probably, the main sources outdoors, whereas indoors combustion activities such as preparation of food, burning of candles, and cigarette smoking were the main sources. In contrast, the concentrations of water-soluble inorganic ions were higher outdoors than indoors. The variability of water-soluble inorganic ion concentrations outdoors was related to changes in emissions from local anthropogenic sources, long-range transport of particles, sea salt emissions, and resuspension of roadside and soil dusts. In the indoor environment the infiltration of the outdoor air indoors was the major source of inorganic ions.  相似文献   
346.
Vogt C  Nowak C  Diogo JB  Oetken M  Schwenk K  Oehlmann J 《Chemosphere》2007,67(11):2192-2200
While toxicological data are available for numerous chemicals from standard tests, little is known on effects of pollutants over several generations or regarding chronic effects of chemicals on genetic diversity. Within the experiments, effects of the model pollutant tributyltin (TBT) were investigated over eleven generations at a sublethal TBT concentration of 4.46 μg as Sn kg−1 sediment dw on life-cycle parameters and genetic variability of Chironomus riparius. Moreover, the adaptation potential towards TBT was determined. This experimental design enables the identification of TBT effects on life-cycle parameters and the determination of a potential extinction risk caused by chronic exposure. Furthermore, effects on the genetic structure can be determined, which are not predictable based solely on knowledge of the toxic mode of action of the chemical.

Genetic variety was determined via microsatellite analysis, measuring individual length differences of highly variable satellite DNA fragments. For the identification of changes in tolerances towards the stressor, acute and chronic toxicity experiments were conducted.

During the multi-generation study, significant effects on development and reproduction were determined. For some generations, the emergence was significantly (p < 0.05) delayed under TBT exposure. Reproduction seems to be a sensitive parameter as well, whereby females laid significantly larger egg masses (p < 0.05) in the latter generations. TBT did not affect the population growth rate nor the genetic variability, while clear deviations from the Hardy–Weinberg equilibrium appeared. The study also provides strong evidence for the acquirement of a higher tolerance towards the stressor in the TBT-exposed group.  相似文献   

347.
Kahle M  Stamm C 《Chemosphere》2007,68(7):1224-1231
Substantial amounts of sulfonamides, ionizable, polar veterinary antimicrobials, may reach the environment by spreading of manure. Sorption to soils and sediments is a crucial but not sufficiently understood process influencing the environmental fate of sulfonamides. Therefore, we investigated sorption of sulfathiazole to clay minerals (montmorillonite, illite) and ferrihydrite for varying pH values and two contact times (1d, 14 d) under sterile conditions. Results were compared to sulfathiazole sorption to organic sorbents. Sulfathiazole sorption to inorganic sorbents exhibited pronounced pH dependence consistent with sorbate speciation and sorbent charge properties. While sulfathiazole cations were most important for sorption to clay minerals, followed by neutral species, ferrihydrite was a specific anion sorbent, showing significant sorption only between pH 5.5-7. Experiments revealed a substantial increase of sorption with time for ferrihydrite (pH 5.5-7) and illite (pH<5.5). Reasons may be disaggregation of clay minerals and, for ferrihydrite, diffusion and sorption of sulfathiazole in micropores. Independent of contact time and pH, sorption to inorganic sorbents was more than an order of magnitude lower than to organic sorbents. This implies that in many topsoils and sediments inorganic sorbents play a minor role. Our results highlight the need to account for contact time and speciation when predicting sulfonamide sorption in the environment.  相似文献   
348.
The toxicity and hazard of a mixture of selective serotonin reuptake inhibitors (SSRIs), including fluoxetine, fluvoxamine, and sertraline, to zooplankton communities were evaluated using 120,00l outdoor microcosms. Acute (day 4) and chronic (day 35) zooplankton abundance and species richness were assessed for Rotifera, Cladocera, and Copepoda. For acute SSRI exposures, rotifers were the most sensitive zooplankton taxa to changes in abundance (predicted no effect concentration (PNEC)=19 nM); however, no effects in zooplankton species richness were observed for this treatment period. A decrease in Copepoda abundance and species richness was observed following chronic exposures of SSRIs (PNEC=9.1 nM). A 99th-centile predicted environmental concentration (PEC=0.51 nM) yielded HQs at least two orders of magnitude below 1. Therefore, mixtures of SSRIs do not appear to present a hazard to zooplankton communities at environmentally relevant concentrations.  相似文献   
349.
Stabilization of Pb- and Cu-contaminated soil using coal fly ash and peat   总被引:4,自引:0,他引:4  
The stabilization of metal contaminated soil is being tested as an alternative remediation method to landfilling. An evaluation of the changes in Cu and Pb mobility and bioavailability in soil induced by the addition of coal fly ash and natural organic matter (peat) revealed that the amount of leached Cu decreased by 98.2% and Pb by 99.9%, as assessed by a batch test. Metal leaching from the treated soil was lower by two orders of magnitude compared to the untreated soil in the field lysimeters. A possible formation of mineral Cu- and Pb-bearing phases and active surface with oxides were identified by chemical equilibrium calculations. Low metal leaching during a two-year observation period, increased seed germination rate, reduced metal accumulation in plant shoots, and decreased toxicity to plants and bacteria, thereby demonstrating this stabilization method to be a promising technique for in situ remediation of Cu and Pb contaminated soil.  相似文献   
350.
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