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91.
This study analyzed discourses influencing the meaning of Sustainable Forest Management in Catalonia (Spain) and the effects of the European Natura 2000 policy on these discourses. It focused on the Montseny area and on the Administration and Practitioner stakeholder groups. Based on literature review and interviews, we found six discourses influencing the meanings of Sustainable Forest Management. Two of these discourses underwent changes due to the effects of Natura 2000 implementation while the others did not, showing the substantial role played by local elements and actors in shaping the discursive framework of Sustainable Forest Management. Based on empirical findings, the study provided conclusions valid at European level: (1) implementing Natura 2000 does not mean revolutionizing local nature conservation systems, but rather adapting them to European requirements; (2) in order to increase local policy impact, the implementation of European environmental policies needs to be backed up by economic compensation of local actors.  相似文献   
92.
This paper explores a technique for mitigating framing effects in perceptions of global climate change. People's opinions on issues ranging from same sex marriage and the environment to free speech and health care have been shown to be influenced by the way in which the issue is presented: the metaphors, images, and catchphrases that communicate implicit normative messages about the issue. The work described here synthesizes insights from experimental research on moderators of framing effects and sociological research on frame reflection. Based on this synthesis, this paper describes a test of a simple highlighting technique for focusing respondents' attention on the framing operating in political materials. Results suggest that this intervention not only can reduce the opinion-shaping impact of frames but may also reduce ideological polarization. Implications include a better understanding of the mechanisms by which frames operate, techniques for making frame reflection possible among political non-elites, and recommendations for strengthening environmental groups' public communication strategies.  相似文献   
93.
The Mediterranean basin, because of its semi-enclosed configuration, is one of the areas heavily affected by air pollutants. Despite implications on both human health and radiative budget involving an increasing interest, monitoring databases measuring air pollution directly over this area are yet relatively limited. Owing to this context, concentrations of fine (PM2.5) and coarse (PM2.5–10) particles along with other ancillary data, such as ozone levels and meteorological parameters, were measured during six cruise campaigns covering almost the whole Mediterranean basin. Elemental composition of both PM2.5 and PM2.5–10 was also determined to identify specific tracers for different classes of particles that can be found in the Mediterranean atmosphere. Outcomes resulting from the integration of a preliminary qualitative examination with a more quantitative analysis, based on receptor modelling, suggested that European continental influence, Saharan dust outbreaks, wildfire events, sea spray and fossil fuel combustion were the leading causes of the aerosol-ozone variations within the Mediterranean basin. Shipping emissions, consisting in both local harbours and maritime traffic across the basin, were also tested using the marker ratio of V/Ni. Peak values observed for coarse fraction have shown to be driven by the occurrence of African dust events. Considering the major influence of Continental pollution and wildfire events, the spatial variability resulted in larger fine particle concentrations and higher ozone levels over the Eastern Mediterranean side in comparison to the Western one.  相似文献   
94.
Phytoremediation is an environmental friendly, cost-effective technology for a soft restoration of abandoned mine sites. The grasses Agrostis capillaris, Deschampsia flexuosa and Festuca rubra, and the annual herb Helianthus annuus were combined with microbial consortia in pot experiments on multi-metal polluted substrates collected at a former uranium mine near Ronneburg, Germany, and a historic copper mine in Kopparberg, Sweden, to test for phytoextraction versus phytostabilization abilities. Metal uptake into plant biomass was evaluated to identify optimal plant–microbe combinations for each substrate. Metal bioavailability was found to be plant species and element specific, and influenced by the applied bacterial consortia of 10 strains, each isolated from the same soil to which it was applied. H. annuus showed high extraction capacity for several metals on the German soil independent of inoculation. Our study could also show a significant enhancement of extraction for F. rubra and A. capillaris when combined with the bacterial consortium, although usually grasses are considered metal excluder species. On the Swedish mixed substrate, due to its toxicity, with 30 % bark compost, A. capillaris inoculated with the respective consortium was able to extract multi-metal contaminants.  相似文献   
95.
The aim of this study was to evaluate the concentration of CA 125 in second trimester amniotic fluid from Down syndrome pregnancies. CA 125 was measured in stored amniotic fluid samples from pregnancies of 14–19 weeks' gestation with and without Down syndrome fetuses. CA 125 levels were expressed in multiples of the median (MOM) for normal pregnancies of the same gestational age. Twenty-one pregnancies with Down syndrome fetuses and 63 unaffected controls matched for maternal age, gestational age, and duration of storage were studied. The median MOM values of the affected pregnancies were significantly higher than those of the controls (1·41 MOM versus 0·99 MOM). These findings show that there is an increased concentration of CA 125 in second-trimester amniotic fluid from Down syndrome pregnancies.  相似文献   
96.
In this paper a comparison about kinetic behaviour, acid-base properties and copper removal capacities was carried out between two different adsorbent materials used for heavy metal removal from aqueous solutions: an aminodiacetic chelating resin as commercial product (Lewatit TP207) and a lyophilised bacterial biomass of Sphaerotilus natans. The acid-base properties of a S. natans cell suspension were well described by simplified mechanistic models without electrostatic corrections considering two kinds of weakly acidic active sites. In particular the introduction of two-peak distribution function for the proton affinity constants allows a better representation of the experimental data reproducing the site heterogeneity. A priori knowledge about resin functional groups (aminodiacetic groups) is the base for preliminary simulations of titration curve assuming a Donnan gel structure for the resin phase considered as a concentrated aqueous solution of aminodiacetic acid (ADA). Departures from experimental and simulated data can be interpreted by considering the heterogeneity of the functional groups and the effect of ionic concentration in the resin phase. Two-site continuous model describes adequately the experimental data. Moreover the values of apparent protonation constants (as adjustable parameters found by non-linear regression) are very near to the apparent constants evaluated by a Donnan model assuming the intrinsic constants in resin phase equal to the equilibrium constants in aqueous solution of ADA and considering the amphoteric nature of active sites for the evaluation of counter-ion concentration in the resin phase. Copper removal outlined the strong affinity of the active groups of the resin for this ion in solution compared to the S. natans biomass according to the complexation constants between aminodiacetic and mono-carboxylic groups and copper ions.  相似文献   
97.
Fungal biodegradation of naphthalene: microcosms studies   总被引:1,自引:0,他引:1  
Mollea C  Bosco F  Ruggeri B 《Chemosphere》2005,60(5):636-643
The present work is aimed to ascertain naphthalene biodegradation capability of P. chrysosporium and T. harzianum in soil microcosms. Considering the high naphthalene volatility, a suitable soil microcosm was set-up and used. Several degradation tests were conducted with different C/N ratio media for the two fungi in order to enquire the best range of working conditions. The kinetic studies were conducted at a maximal naphthalene concentration of 600 mg kg(-1). During experimental time course naphthalene concentration, CO2 evolution as well as phytotoxicity tests were performed as monitoring parameters. The results shown in the current paper, put in evidence that T. harzianum, differently than in liquid culture, is not able to biodegrade naphthalene directly in soil microcosm, while P. chrysosporium in the same conditions biodegrades the PAH till about 600 mg kg(-1). As concern the founded kinetics for P. chrysosporium, a saturation shape in presence of N-limited medium (high C/N ratio) was evaluated while a growing form more than linear in no-N limited medium (normal C/N ratio) was determined.  相似文献   
98.
Gastropod shells are limited resources for most hermit crab species, acting as primary factors in various aspects of their biology. To investigate the efficacy of different behavioral tactics adopted for their acquisition (locomotion, attendance at shell-supplying sites, interactions with conspecifics in aggregation) we conducted observations and experiments at a salt marsh in New England (USA). Locomotion, fast and meandering, significantly increased the chances of encountering empty shells and conspecifics. However, shell exchanges were rare. Simulated gastropod predation sites quickly attracted a larger number of hermit crabs than the other shell-supplying sites tested (live and dead conspecifics, live snails) and induced the rapid occupancy of all the empty shells offered, usually by the first crabs arriving at the site. Aggregations seemed not to function as shell exchange markets, as previously suggested for several other species. In the short run, exploitation seems to be more efficient for the acquisition of new shells by Pagurus longicarpus. In the long run, it is the density of nondestructive gastropod predators that regulates the availability of new shells of good quality in the pool available to this hermit crab species.  相似文献   
99.
A phylogenetic analysis of some bioeroding sponges of the family Clionaidae (Order Hadromerida) was performed to resolve some taxonomic problems both at the specific and the supraspecific level using the D2 and D3 regions of 28S rDNA. Species belonging to the genera Cliona, Cliothosa, Spheciospongia (fam. Clionaidae) and Diplastrella (fam. Spirastrellidae) from the Mediterranean Sea and Celebes Sea (Indonesia) were analysed. In the phylogenetic tree, the species clustered on two main branches, one comprising Cliona celata, C. rhodensis, C. utricularis, and Cliothosa hancocki, and the other made up of C. viridis, C. nigricans, C. schmidti, C. jullieni, Spheciospongia solida and S. vagabunda. Above the species level, data do not support the separation of the genus Cliothosa from Cliona, while they do support the inclusion of some massive boring species, previously assigned to the genus Spirastrella, in the family Clionaidae. At the species level, data demonstrated the genetic identity of taxa C. viridis and C. nigricans, in spite of their considerable morphological differences. In contrast, the yellow species commonly attributed to C. celata are probably to be considered as a complex of sibling species with a number of distinct taxa present in the Mediterranean. Data also showed the identity of the Mediterranean and Pacific populations of C. schmidti, suggesting the status of a Tethyan relict for this species.  相似文献   
100.
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