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171.
Decision makers interested in promoting sustainable development must simultaneously consider the environmental, economic and social implications of any action. This article proposes the Framework for Integrated Sustainability Assessment (FISA), a methodological framework for conducting a sustainability impact assessment of any investment project. Based on a Multiregional Input–Output (MRIO) framework, FISA links the extended MRIO results with social risk data from the Social Hotspots Database (SHDB) in order to integrate the social with the environmental and economic pillars. Resulting impacts are simultaneously considered and reported by means of FISA charts, making it possible to assess the different impacts within the three sustainability pillars across countries involved in the whole supply chain of investment projects. This methodological framework can be applied not only to compare the sustainability impacts of two alternative projects, but also to derive specific recommendations aimed at minimizing the harmful social, environmental and economic effects along the whole project supply chain.  相似文献   
172.
Issue cycles in media reporting and in the coverage of environmental news in particular have been studied since the 1970s. This study seeks to extend existing theory on issue-attention lifecycles from the news-media domain to the corporate domain by exploring how companies operationalize environmental sustainability over time. Using computer-assisted text analysis, this study investigates 744 corporate environmental reports in a 10-year longitudinal design in order to study how the attention that companies pay to a set of 13 environmental issues shifts over this period. The results indicate discernible issue cycles for almost all of the issues studied. Some issues are in a phase of heightened awareness, others in a punctuated equilibrium following specific events, and even others in a phase of decline. The issue cycles identified suggest that companies pursue their environmental strategies consistently, but shift attention to particular issues as a response to high-profile environmental events. Policy-makers therefore need to be aware of the slowness of changes in corporate environmental strategies.  相似文献   
173.
Zhang W  Zhuang L  Tong L  Lo IM  Qiu R 《Chemosphere》2012,86(8):809-816
Cr(VI) was often reported to oxidize soil organic matter at acidic environments due to its high ORP, probably thus changing cationic metal species bound to soil organic matter, and influencing their electro-migration patterns. However, such an effect on the electro-migration was not confirmed in most previous studies. Therefore, this study applied a fixed voltage direct current field on an aged electroplating contaminated clayed soil, with a special interest in the direct or indirect influence of Cr(VI) on the electro-migration of other coexisting metals. After 353 h electrokinetic process, 81% of Zn, 53% of Ni and 22% of Cu in the original soil were electro-migrated into the electrolyte, and most of the remaining concentrated near the cathode. The Cr(VI) oxidized some soil organic matter along its migration pathway, with a pronounced reaction occurred near the anode at low pHs. The resulting Cr(III) reversed its original movement, and migrated towards the cathode, leading to the occurrence of a second Cr concentration peak in the soil. Metal species analyses showed that the amount of metals bound to soil organic matter significantly decreased, while a substantial increase in the Cr species bound to Fe/Mn (hydro-)oxides was observed, suggesting an enhancement of cationic metal electro-migration by the reduction of Cr(VI) into Cr(III). However, the Cr(VI) may form some stable lead chromate precipitates, and in turn demobilize Pb in the soil, as the results showed a low Pb removal and an increase in its acid-extractable and residual fractions after electrokinetic remediation.  相似文献   
174.
The current study represents the first investigation of the suitability of wolf hair as indicator tissue for metal exposure and accumulation within NW Spanish ecosystems. Dead animals, which were not specifically killed for these purposes, were necropsied, and further toxicological analyses were performed in order to establish the heavy metal content (Pb, Cd, and Zn) in liver, kidney, and hair, by means of inductively coupled plasma optical emission spectrometry. Two different factors, gender and age, were considered in order to determine their influence on heavy metal accumulation. Mean liver, kidney and hair concentrations of both toxic element, Cd (0.528, 2.692, and 0.026 ppm) and Pb (4.108, 0.031, and 0.196 ppm) considered on a dry weight basis, were situated below the established as acute toxicity levels for mammals. The highest concentrations were quantified for Zn, with means ranging from a maximum in hair samples (150.9 ppm) to a minimum in kidney samples (25.81 ppm). When the variable of gender and age were considered, female and adult wolves had higher concentrations of Cd in all the considered organs, although differences were only statistically significant for kidney. Neither the sex nor the age had a significant effect on Pb and Zn concentrations. A significant positive correlation (p?<?0.05) was identified between hair and liver Pb concentrations, as well as between hair and kidney Cd concentrations, thus suggesting the interest of the noninvasive sample for future ecotoxicological biomonitoring studies.  相似文献   
175.
Invasive species are one of the greatest threats to biodiversity worldwide, and to successfully manage their introductions is a major challenge for society. Knowledge on the impacts of an invasive species is essential for motivating decision makers and optimally allocating management resources. We use a prominent invasive fish species, the round goby (Neogobius melanostomus) to objectively quantify the state of scientific knowledge on its impacts. Focusing on how native fish species are affected by round goby invasions, we analyzed 113 peer-reviewed papers and found that impacts are highly ecosystem and time scale dependent. We discovered round goby impacts to be profound, but surprisingly complex. Even if identical native species were affected, the impacts remained less comparable across ecosystems than expected. Acknowledging the breadth but also limitations in scientific knowledge on round goby impacts would greatly improve scientists’ ability to conduct further research and inform management measures.

Electronic supplementary material

The online version of this article (doi:10.1007/s13280-015-0718-9) contains supplementary material, which is available to authorized users.  相似文献   
176.
177.
In order to evaluate the water quality at the surface/groundwater interface (hyporheic zone), the pattern of microcrustacean assemblages in response to environmental stress caused by urban industrial contamination was studied in the Jarama River basin (central Spain) during high water discharges (March and April 2011). The clustering of biological variables and the concentration of urban contaminants in hyporheic waters showed that pristine hyporheic waters have moderate species diversity (two to seven species) and dominance of k strategist stygobites, whereas excessively contaminated sites are devoid by crustaceans. An intermediate level of disturbance in hyporheic waters is associated with a peak of species taxonomic diversity (four to nine species) and proliferation of r strategist more tolerant species. Typical species found in hyporheic zone, e.g., Paracyclops imminutus (Copepoda, Cyclopoida), Cryptocandona vavrai (Ostracoda) and Herpetocypris chevreuxi (Ostracoda), were good indicators of high concentrations of Cr, Mn, Ni, Cd, Pb and VOCs; whereas the stygobites do not show any significant correlation. The effectiveness of hyporheic crustaceans as efficient bioindicators for assessing the current ecological status of river ecosystems is emphasised.  相似文献   
178.
Hydrogen peroxide-assisted UV photodegradation of Lindane   总被引:1,自引:0,他引:1  
Aqueous solutions of gamma-hexachlorocyclohexane (Lindane) were photolyzed (lambda=254 nm) under a variety of solution conditions. The initial concentrations of hydrogen peroxide (H(2)O(2)) and Lindane varied from 0 to 20 mM and 0.21 to 0.22 microM, respectively, the pH ranged from 3 to 11, and several concentration ratios of Suwannee River humic acid and fulvic acid were dissolved in the irradiated solutions. Lindane rapidly reacted, and the maximum reaction rate constant (9.7 x 10(-3) s(-1)) was observed at pH 7 and initial [H(2)O(2)]=1 mM. Thus, 90% of the Lindane is destroyed in approximately 4 min under these conditions. In addition, within 15 min, all chlorine atoms were converted to chloride ion, indicating that chlorinated organic by-products do not accumulate. The reactor was characterized by measuring the photon flux (7.04 x 10(-6) E s(-1)) and the cumulative production of *OH during irradiation. The cumulative *OH production during irradiation was fastest at an initial [H(2)O(2)]=5 mM (k=0.77 micro M s(-1)).  相似文献   
179.
Fishing the line near marine reserves in single and multispecies fisheries.   总被引:3,自引:0,他引:3  
Throughout the world "fishing the line" is a frequent harvesting tactic in communities where no-take marine reserves are designated. This practice of concentrating fishing effort at the boundary of a marine reserve is predicated upon the principle of spillover, the net export of stock from the marine reserve to the surrounding unprotected waters. We explore the consequences and optimality of fishing the line using a spatially explicit theoretical model. We show that fishing the line: (1) is part of the optimal effort distribution near no-take marine reserves with mobile species regardless of the cooperation level among harvesters; (2) has a significant impact on the spatial patterns of catch per unit effort (CPUE) and fish density both within and outside of the reserve; and (3) can enhance total population size and catch simultaneously under a limited set of conditions for overexploited populations. Additionally, we explore the consequences of basing the spatial distribution of fishing effort for a multispecies fishery upon the optimality of the most mobile species that exhibits the greatest spillover. Our results show that the intensity of effort allocated to fishing the line should instead be based upon more intermediate rates of mobility within the targeted community. We conclude with a comparison between model predictions and empirical findings from a density gradient study of two important game fish in the vicinity of a no-take marine-life refuge on Santa Catalina Island, California (USA). These results reveal the need for empirical studies to account for harvester behavior and suggest that the implications of spatial discontinuities such as fishing the line should be incorporated into marine-reserve design.  相似文献   
180.
Disaggregating seagrass meadows and studying its components separately (clones, ramets, shoots) can provide us insights on meadow dynamics and growth patterns. The clonal growth, dependent upon clonal rules may regulate and impose constraints to plant architecture and, therefore, determine how individual clones evolve into the environment. In order to investigate the relationship between clonal growth rules and clone architecture, the belowground network architecture of single-clones of the seagrass Zostera noltii was studied. Networks were traced in situ after washing out the overlying sediment, and network characteristics were measured using digital analysis: area covered by clone, total rhizome length, type of rhizomatic axes (main, secondary, tertiary, quaternary), number and length of the internodes, branching angles and branching frequencies. This approach revealed that Z. noltii is able to develop into large clones integrating up to 300 internodes, 676 cm of rhizome, 208 shoots and 4,300 cm2 of plant area. Internodal length depended on both, the distance to the apical shoot (time effect) and the axes type (apical dominance effect). However, average branching angle was independent of axis type (average 58.3 ± 0.75), but varied significantly depending on the distance from the apical shoot. This average branching angle allows Z. noltii maximize the rate of centrifugal expansion, maintaining a high density in colonized areas to produce close stands but also minimizing the investment in belowground biomass and ramets overlapping. The clonal architecture of Z. noltii seems to be regulated by the interaction of both, apical dominance strength and clonal integration distance. Moreover, clonal growth rules and growth pattern seem to constrain clonality through (clonal) plant architecture regulations (i.e. branching is restricted in secondary axes, similar average branching angles regardless the axes, the higher the distance to the apex the higher the number of internodes in secondary axes, shorter internodes in secondary and tertiary axes). Future research efforts should focus on how these complex relationships between apical dominance and clonal integration interact to elucidate the temporal (seasonal) and spatial scales of both processes and the outcome at the plant architectural level.  相似文献   
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