Air pollution from a large steel factory: polycyclic aromatic hydrocarbon emissions from coke-oven batteries

A systematic investigation of solid and gaseous atmospheric emissions from some coke-oven batteries of one of Europe's largest integrated steel factory (Taranto, Italy) has been carried out. In air monitoring samples, polycyclic aromatic hydrocarbons (PAHs) were consistently detected at concentrations largely exceeding threshold limit values. By means of PAHs speciation profile and benzo(a)pyrene (BaP) equivalent dispersion modeling from diffuse sources, the study indicated that serious health risks exist not only in working areas, but also in a densely populated residential district near the factory.     

HEAVY METAL DISTRIBUTION AND SPECIATION IN THE NORTHERN ADRIATIC SEA

In the present study the concentrations of cobalt, copper, iron, manganese, zinc were analysed and the speciation of copper and zinc performed, with a summer and winter sampling, for two areas in the Northern Adriatic Sea and crossing at the farthest zones of the Po river-sea water interface. Results show that when salinity increases the concentrations of all investigated metals (with the exception of cobalt) present some degree of biogeochemical cycling. Copper is the element whose dissolved phase has the highest importance in metal transport across the salinity gradient. Results of speciation analysis demonstrate that the presence of excess amounts (5-8 fold) of unbound ligands confers a buffering capacity for potential inputs of dissolved metals into the Northern Adriatic Sea. The speciation of both copper and zinc in the dissolved phase was dominated by organic complexation.     

The function of polydomy: the ant <Emphasis Type="Italic">Crematogaster torosa</Emphasis> preferentially forms new nests near food sources and fortifies outstations

Many ant species are polydomous, forming multiple spatially segregated nests that exchange workers and brood. However, why polydomy occurs is still uncertain. We investigated whether colonies of Crematogaster torosa form new polydomous nests to better exploit temporally stable food resources. Specifically, we tested the effect of food presence or absence and distance on the likelihood that colonies would form a new nest. Because this species also forms little-known structures that house only workers without brood (outstations), we also compared the function of this structure with true nests. Laboratory-reared colonies were connected to a new foraging arena containing potential nest sites with or without food for 4 months. When food was present, most colonies formed polydomous nests nearby and the remainder formed outstations. When food was absent, the behavior of colonies differed significantly, frequently forming outstations but never polydomous nests. Distance had no effect on the type of structure formed, but when food was present, a larger proportion of the workforce moved shorter distances. Workers often fortified the entrances to both structures and used them for storage of dried insect tissue (“jerky”). In an investigation of spatial fidelity, we found that workers on the between-nest trail were associated with the original nest, whereas workers collecting food were more likely to be associated with the new nest or outstation. C. torosa appears to have a flexible colony structure, forming both outstations and polydomous nests. Polydomous nests in this species were associated with foraging and were only formed near food resources.     

Pollution prevention at the 3M corporation: Case study insights into organizational incentives, resources, and strategies

3M initiated its “Pollution Prevention Pays” (3P) program in 1975 and is probably the U.S. corporation which has been most identified with using preventive strategies to reduce toxic releases. This case study draws on interviews conducted with representatives of 3M manufacturing plants and corporate staff to provide both an overview of 3M's pollution prevention efforts and explore the organizational dimensions of two types of pollution prevention projects. The analysis addresses two key questions: (1) what do 3M's accomplishments indicate about the potential for pollution prevention approaches? and (2) what are the organizational incentives, resources and strategies which underpin 3M's pollution prevention efforts?     

Turbulence investigation in the roughness sub-layer of a near wall flow

The turbulence behaviour along a wall roughened by pyramidal elements was analysed in the region extending from the apex of the roughness elements up to the external limit of the roughness sub-layer. The data used for the analysis were obtained by particle image velocimetry technique. The rough wall turbulent boundary layer flow is characterized by a relatively low Reynolds number. All the results on the rough wall were compared with data referring to the canonical flow on a smooth wall turbulent boundary layer. Mean values and turbulence quantities for the two flows collapse when approaching the external limit of the roughness sublayer. The quadrant analysis of the Reynolds shear stress, in the region near the surface, shows that the contribution of the sweep motions is about equivalent for the two flows (except for wall distances lower than 40 viscous units). The contribution of the ejection motions appears to be more important over the smooth wall than over the rough wall with increasing differences approaching the wall. The probability density functions of the streamwise fluctuating velocity field for the rough wall case appear to be positively skewed in the zone very close to the pyramid apex, in contrast with the behavior observed for the smooth wall case at corresponding distances from the wall. The integral and Taylor scales for the rough wall case appear to be strongly reduced by the presence of the roughness, while the Kolmogorov microscale shows higher values.     

Mechanical properties of Municipal Solid Waste by SDMT

In the paper the results of a geotechnical investigation carried on Municipal Solid Waste (MSW) materials retrieved from the “Cozzo Vuturo” landfill in the Enna area (Sicily, Italy) are reported and analyzed. Mechanical properties were determined both by in situ and laboratory large-scale one dimensional compression tests.While among in situ tests, Dilatomer Marchetti Tests (DMT) is used widely in measuring soil properties, the adoption of the DMT for the measurements of MSW properties has not often been documented in literature. To validate its applicability for the estimation of MSW properties, a comparison between the seismic dilatometer (SDMT) results and the waste properties evaluated by laboratory tests was carried out.Parameters for “fresh” and “degraded waste” have been evaluated. These preliminary results seems to be promising as concerns the assessment of the friction angle of waste and the evaluation of the S-wave in terms of shear wave velocity. Further studies are certainly required to obtain more representative values of the elastic parameters according to the SDMT measurements.     

Markets and the crowding out of conservation-relevant behavior

Markets are increasingly being incorporated into many aspects of daily life and are becoming an important part of the conservation solution space. Although market-based solutions to environmental problems can result in improvements to conservation, a body of social science research highlights how markets may also have unforeseen consequences by crowding out or displacing 3 key types of behaviors potentially relevant to conservation, including people's willingness to engage in collective action and civic duty; tolerance for inflicting harm on others (third-party externalities); and desire for equity. Better understanding of the contexts and mechanisms through which this crowding out occurs and whether specific market-based instruments are more prone to different types of crowding out will be crucial to developing novel conservation initiatives that can reduce or prevent crowding out.     

Mercury removal, methylmercury formation, and sulfate-reducing bacteria profiles in wetland mesocosms

A pilot-scale model was constructed to determine if a wetland treatment system (WTS) could effectively remove low-level mercury from an outfall located at the Department of Energy's Savannah River Site. Site-specific hydrosoil was planted with giant bulrush, Scirpus californicus, and surface amended with gypsum (CaSO4) prior to investigating the biogeochemical dynamics of sediment-based sulfur and mercury speciation. On average, the pilot WTS decreased total mercury concentrations in the outfall stream by 50%. Transformation of mercury to a more "bioavailable" species, methylmercury, was also observed in the wetland treatment system. Methylmercury formation in the wetland was ascertained with respect to sediment biogeochemistry and S. californicus influences. Differences in sulfate-reduction rates (SRRs) were observed between mesocosms that received additional decomposing Scirpus matter and mesocosms that were permitted growth of the submerged macrophyte, Potamogeton pusillus. Relative abundance measurements of sulfate-reducing bacteria (SRB) as characterized using oligonucleotide probes were also noticeably different between the two mesocosms. A positive correlation between increased sulfide, dissolved total mercury, and dissolved methylmercury concentrations was also observed in porewater. The data suggest that soluble mercury-sulfide complexes were formed and contributed, in part, to a slight increase in mercury solubility. Observed increases in methylmercury concentration also suggest that soluble mercury-sulfide complexes represent a significant source of mercury that is "available" for methylation. Finally, a volunteer macrophyte, Potamogeton pusillus, is implicated as having contributed additional suspended particulate matter in surface water that subsequently reduced the pool of dissolved mercury while also providing an environment suitable for demethylation.