Environmental release and mass flux partitioning of PCDD/Fs during normal and transient operation of full scale waste to energy plants

The paper reports on global release and mass partitioning in the flux of residues of PCDD/Fs, evaluated with dedicated field campaigns at a municipal solid waste incineration plant during normal and transient operation. Results are compared with those obtained in other installations equipped with furnaces, energy recovery options and flue gas treatment technologies representative of most of the European incineration plants currently in operation. Levels of the pollutants of interest were determined in all the solid, liquid and gaseous residues produced by every single facility, and the results analysed in terms of the effects arising from the fed waste and the configuration of the plant. PCDD/Fs total release between 1.5 and 45 microg I-TEQ per ton of burned waste was evaluated, with lower values resulting from the adoption of catalytic conversion process for flue gas treatment. Most of the mass flux emitted is associated with solid residues deriving from activated carbon PCCD/F dry removal options, with significant contributions also from fly ash produced by particulate removal devices located immediately downstream the boiler and from scrubber blowdowns treatment sludge. During transient operating conditions the dioxin total release may increase by 50% with comparison to steady-state functioning.     

Evaluation of the impact on entomocoenosis of active agents allowed in organic olive farming against Bactrocera oleae (Gmelin, 1790)

Several attempts for evaluating environmental impact of active agents allowed in organic olive farming against Bactrocera oleae have been made, but very few studies were performed contemporaneously on more than one of them. Insects were chosen as indicators because they are known to react very quickly to environmental perturbations, mainly at the community level. In fact, the coenosis is the functional unit interacting with biotic and abiotic environmental parameters. Seven taxa, known for their sensitivity to habitat alterations, were sampled and grouped in functional groups: predators and parasitoids, phytophagouses and pollinators. The coenotic balance between these two functional groups was analyzed. The study was carried out in an organic olive orchard in the municipality of Terranova da Sibari, Cosenza, Southern Italy. The tested active agents (Azadirachtin, Rotenone, Copper Oxychloride) were sprayed twice (end of September and middle October). During the treatments the population dynamics of all the taxa were knocked-down. No one tested compound seems to be harmless to the entomocoenosis, particularly on phytophagouses and pollinators. In truly organic farming it is necessary to provide natural refuge areas to beneficial insects (i.e. pest antagonists) in which no active agents are sprayed and alternative preys could be found.     

Distribution of Cd and As in organs and tissues of four marine mammal species stranded along the Italian coasts

Concentrations of Cd and As were determined in organs and tissues (muscle, heart, kidney, lung and liver) of four cetacean species (Stenella coeruleoalba, Truncatus truncatus, Grampus griseus and Ziphius cavirostris) stranded along the Italian coasts during the period 2000-2009. Significant differences were found between Cd concentrations in the different analysed tissues. Particularly, the kidney shows the highest concentrations of Cd in all analysed specimens, followed by the liver. No systematic or statistically significant difference in As concentrations was found in the analysed tissues. Considerable differences of Cd and As values in samples from different geographical areas (Sicily Channel, Adriatic Sea and Tyrrhenian Sea) were found, with the highest values measured in samples from the Sicily Channel. This basically suggests that anthropogenic and natural sources significantly affect Cd and As content in cetaceans.     

Identification of stationary sources of air pollutants by concentration statistical analysis

The atmospheric concentrations of benzene, toluene, ethylbenzene and isomeric xylenes (BTEX) in a medium-sized town (S. Maria Capua Vetere, about 32000 inhabitants, Southern Italy) have been determined during working days and weekends in 2006. The procedure used was 24h passive adsorption by samplers distributed throughout the town followed by GC/MS analysis. On a yearly base, the arithmetic mean benzene concentrations were above the limit required by the 2000/69/CE European Directive. The Pearson correlation coefficients of the 24h geometric mean BTEX concentrations were indicative of stationary sources of toluene located in a well circumscribed area of the urban territory, active only during the working days and not officially recognized. The results highlight the effectiveness of the statistical approach used in this study for the identification of pollutant sources.     

Remote sensing water observation for supporting Lake Victoria weed management

This paper aims to assess the suitability of remote sensing for enhancing the management of water body resources and for providing an inexpensive way to gather, on a wide area, weed infestation extent and optical parameter linked to the water body status. Remotely sensed satellite images and ancillary ground true data were used to produce land cover maps, trough classification techniques, and water compounds maps, applying radiative transfer models. The study proposed within the framework of the cooperation between Italian Foreign Affair Ministry (through the University of Rome) and Kenyan Authorities has been carried out on the Kenyan part of the Lake Victoria. This lake is one of the largest freshwater bodies of the world where, over the last few years environmental challenges and human impact have perturbed the ecological balance affecting the biodiversity. The objective of this research study is to define the thematic products, retrievable from satellite images, like weed abundance maps and water compound concentrations. These products, if provided with an appropriate time frequency, are useful to identify the preconditions for the occurrence of hazard events like abnormal macrophyte proliferation and to develop an up-to-date decision support system devoted to an apprised territory, environment and resource management.     

TG, FT-IR and NMR characterization of n-C16H34 contaminated alumina and silica after mechanochemical treatment

This paper deals with the application of mechanochemistry to model systems composed of alumina or silica artificially contaminated with n-C16H34. The mechanochemical treatment was carried out by means of a ring mill for times ranging from 10 to 40h. Thermogravimetry and infrared and nuclear magnetic resonance spectroscopies were used for the characterization of the mechanochemical products. The results have indicated that, in the case of alumina, almost all the contaminant n-C16H34 undergoes a complex oxidative reaction path whose end products are strongly held on the surface. These end products are most likely made of crosslinked, partially oxidized hydrocarbon chains bond to the solid surface via COO(-) groups. In the case of silica, the hydrocarbon undergoes a different, equally complex reaction path, but to a lower extent. In this case the end products are most probably carbonylic compounds and graphitic carbon. Then, for both solid matrices, the mechanochemical treatment promotes significant modification of the chemical nature of the polluting hydrocarbon with end products much more difficult to remove from the surface. As the systems studied are models of sites contaminated by aliphatic hydrocarbon, the results are worthy of consideration in relation to the mobility of the contaminants in the environment.     

Environmental and biological monitoring of iridium in the city of Rome

The use of iridium in the latest catalytic converters to further reduce nitrogen oxide emission in the exhaust of lean-burn engines could result in increased atmospheric levels of this element in high-density vehicle traffic areas. The objective of this study is to assess environmental Ir pollution and its urinary levels in workers and an urban control group. Environmental monitoring inside a tram consisted in air samplings of total suspended particles (TSP), PM10 and PM2.5 carried out during November 2005. Urinary Ir levels were evaluated in 64 municipal tram drivers and in 58 administrative employees as controls. Quantification of Ir in air samples and urine was performed by means of Sector Field Inductively Coupled Plasma Mass Spectrometry. Means+/-standard deviation of Ir levels in TSP, in PM10 and PM2.5 fractions were 1.43+/-1.66, 0.44+/-0.27 and 0.36+/-0.19 pg m(-3), respectively. No statistically significant differences were observed among urinary Ir values in the exposed subjects and control group. The Ir levels in Rome air are still sufficiently low, even if the increased use of new Ir-based catalysts could be of some concern in the near future. The results of our study are of interest as they are a first attempt to explore airborne levels and urinary concentrations of Ir in an urban context at medium-high density of vehicle traffic. Particular attention should be given to the fact that Ir was found in the finest dust particles as the effects of fine particles containing Ir have not yet been studied.     

Integrating functional connectivity and fire management for better conservation outcomes

Globally, the mean abundance of terrestrial animals has fallen by 50% since 1970, and populations face ongoing threats associated with habitat loss, fragmentation, climate change, and disturbance. Climate change can influence the quality of remaining habitat directly and indirectly by precipitating increases in the extent, frequency, and severity of natural disturbances, such as fire. Species face the combined threats of habitat clearance, changing climates, and altered disturbance regimes, each of which may interact and have cascading impacts on animal populations. Typically, conservation agencies are limited in their capacity to mitigate rates of habitat clearance, habitat fragmentation, or climate change, yet fire management is increasingly used worldwide to reduce wildfire risk and achieve conservation outcomes. A popular approach to ecological fire management involves the creation of fire mosaics to promote animal diversity. However, this strategy has 2 fundamental limitations: the effect of fire on animal movement within or among habitat patches is not considered and the implications of the current fire regime for long-term population persistence are overlooked. Spatial and temporal patterns in fire history can influence animal movement, which is essential to the survival of individual animals, maintenance of genetic diversity, and persistence of populations, species, and ecosystems. We argue that there is rich potential for fire managers to manipulate animal movement patterns; enhance functional connectivity, gene flow, and genetic diversity; and increase the capacity of populations to persist under shifting environmental conditions. Recent methodological advances, such as spatiotemporal connectivity modeling, spatially explicit individual-based simulation, and fire-regime modeling can be integrated to achieve better outcomes for biodiversity in human-modified, fire-prone landscapes. Article impact statement: Land managers may conserve populations by using fire to sustain or enhance functional connectivity.