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81.
We re-sequenced 815 bp of the mtDNA of loggerhead turtles from a population nesting in Calabria (southern Italy), which was found recently. Non-invasive sampling was applied and information on deposition date and place was used to avoid possible resampling of nesting females. Among 38 nests laid by independent females, we found the common haplotype CC-A2.1 (57.9%) and two other haplotypes which have never been described in Mediterranean nesting grounds, CC-A20.1 (36.8%) and CC-A31.1 (5.3%). Calabria harbors the highest intra-population diversity among 11 Mediterranean nesting populations. Our findings narrow the gap between haplotypes recorded in feeding grounds and those found in nesting grounds. Analyses of population structure show a strong maternal isolation, with Calabria and east Turkey displaying far more diversity than expected considering their census size. These observations suggest that recurrent female founder effects from sources yet to be identified in the Atlantic or in the Mediterranean may have shaped the pattern of mtDNA diversity in this latter basin. Our results provide evidence that the Ionian Calabrian sites should be protected because of the high diversity found there. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
82.
Understanding patterns, dynamics, and drivers of land use is crucial for improving our ability to cope with sustainability challenges. The human appropriation of net primary production (HANPP) framework provides a set of integrated socio-ecological indicators that quantify how land use alters energy flows in ecosystems via land conversions and biomass harvest. Thus, HANPP enables researchers to systematically and consistently assess the outcome of changes in land cover and land-use intensity across spatio-temporal scales. Yet, fine-scale HANPP assessments are so far missing, an information important to address site-specific ecological implications of land use. Here, we provide such an assessment for Europe at a 1-km scale for the years 1990, 2000, and 2006. The assessment was based on a consistent land-use/biomass flow dataset derived from statistical data, remote sensing maps, and a dynamic global vegetation model. We find that HANPP in Europe amounted to ~43 % of potential productivity, well above the global average of ~25 %, with little variation in the European average since 1990. HANPP was highest in Central Europe and lower in Northern and Southern Europe. At the regional level, distinct changes in land-use intensity were observed, most importantly the decline of cropland areas and yields following the breakdown of socialism in Eastern Europe and the subsequent recovery after 2000, or strong dynamics related to storm events that resulted in massive salvage loggings. In sum, however, these local dynamics cancelled each other out at the aggregate level. We conclude that this finding warrants further research into aspects of the scale-dependency of dynamics and stability of land use.  相似文献   
83.
Mercury policy and regulations for coal-fired power plants   总被引:1,自引:1,他引:0  

Introduction  

Mercury is a high-priority regulatory concern because of its persistence and bioaccumulation in the environment and evidence of its having serious adverse effects on the neurological development of children.  相似文献   
84.
There is a recent increase in the interest of designing high-performance photocatalysts using graphene-based materials. This review gathers some important aspects of graphene?CTiO2, graphene oxide?CTiO2, and reduced graphene oxide?CTiO2 composites, which are of especial relevance as next generation photocatalysts. The methods used for the preparation of these materials, the associated mechanistic fundamentals, and the application of graphene-based composites on the photocatalytic degradation of pollutants are reviewed. Some structural, textural, and chemical properties of these materials and other photo-assisted applications, such as hydrogen production from water splitting and dye-sensitized solar cells, are also briefly included.  相似文献   
85.
Thirteen PAHs, five nitro-PAHs and two hydroxy-PAHs were determined in 55 vapor-phase samples collected in a suburban area of a large city (Madrid, Spain), from January 2008 to February 2009. The data obtained revealed correlations between the concentrations of these compounds and a series of meteorological factors (e.g., temperature, atmospheric pressure) and physical–chemical factors (e.g., nitrogen and sulfur oxides). As a consequence, seasonal trends were observed in the atmospheric pollutants. A “mean sample” for the 14-month period would contain a total PAH concentration of 13 835 ± 1625 pg m−3 and 122 ± 17 pg m−3 of nitro-PAHs. When the data were stratified by season, it emerged that a representative sample of the coldest months would contain 18 900 ± 2140 pg m−3 of PAHs and 150 ± 97 pg m−3 of nitro-PAHs, while in an average sample collected in the warmest months, these values drop to 9293 ± 1178 pg m−3 for the PAHs and to 97 ± 13 pg m−3 for the nitro-PAHs. Total vapor phase concentrations of PAHs were one order of magnitude higher than concentrations detected in atmospheric aerosol samples collected on the same dates. Total nitro-PAH concentrations were comparable to their aerosol concentrations whereas vapor phase OH-PAHs were below their limits of the detection, indicating these were trapped in airborne particles.  相似文献   
86.
The Naples's harbour is one of the largest and most important commercial and tourist port of the Mediterranean basin. It is located on the southeast coast of Italy and receives industrial and municipal wastewaters from the city of Naples. Due to its social and economic impact, a comprehensive assessment of levels and sources of contamination of bottom sediments in this area of the Mediterranean basin is essential to identify potential danger due to mobilization of contaminants produced by managing of the same sediments. In this study, superficial sediments collected from 189 sampling sites were analyzed for grain size, heavy metals (Cr, Cu, Ni, Pb, V, Zn, Co, Sn, Cd, Hg, As, Al and Fe), 16 priority polycyclic aromatic hydrocarbons (PAHs) and perylene and 38 individual polychlorinated biphenyl (PCB) congeners. Compared to the estimated local background, Cu, Zn, Pb, Cd, Sn and Hg show enrichment factors >3 and only Hg evidences a median value higher than the NOAA (effects range - median) guidelines. Principal component analysis allowed us to clearly discriminate two areas mainly affected by heavy metals contamination and influenced by different sources related to industrial, commercial and/or urban activities. Priority PAHs are predominantly represented by three-five-ring compounds with concentrations ranging between 9 and 31774 ng g(-1) and frequently higher than the NOAA ER-M index. A prevalent pyrolitic origin of PAH was assessed on the basis of the relative abundance of the different congeners and selected isomer ratios. The concentrations of PCBs, as sum of the 38 congeners, ranged from 1 to 899 ng g(-1), with a predominance of highly chlorinated (tetra- and penta-chlorobiphenyls) congeners. WHO-TEQ values, calculated for the PCDD-like PCB congeners, suggest a relatively high level of toxicity. Generally, the concentration of PAHs and PCBs were higher near the sites of intense industrial, shipping and/or commercial activities suggesting a direct influence of these sources on the pollutant distribution patterns.  相似文献   
87.
The cathode ray tube (CRT) glass is one of the most important problem that afflicts the electronic waste disposal whose solution lies in the identification of efficient and ecofriendly processes to detoxify and reutilize lead-contained funnel glass. This study is focused on a rapid screening of different chemical and mechanochemical processes to reduce lead content in waste CRT glass downgrading the risk correlated to it. In particular, as a possibility to clean waste CRT glass, treatments of lead-containing glass with different chelating agents (EDTA, NTA, ATMP, EDTMP and HEDP) were performed to evaluate their extractive capabilities. Furthermore, the influence of the grinding, the chelating agent functional groups (polyamino-carboxylic acid, carboxylic acid, and polyamino phosphonic acid), and the time and the temperature on lead content reduction were analyzed. ESEM and EDS analysis were performed on all the samples to evaluate the lead amount before and after the treatments.  相似文献   
88.
89.
Environmental Science and Pollution Research - In recent years, the proliferation of Harmful Cyanobacterial Blooms (CyanoHABs) has increased with water eutrophication and climate change, impairing...  相似文献   
90.
Environmental Science and Pollution Research - In this study, we determined the levels of elements (i.e. As, Be, Cd, Cr, Hg, Ni, Pb, U, and Zn) in bees and edible beehive products (honey, wax,...  相似文献   
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