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431.
In the eggs and developing chick livers in the two wild bird species, great cormorant and herring gull, the concentrations of a range of 15 perfluoroalkyl acids (PFAAs) were determined. Eggs of the two species were collected from Lake Vänern, Sweden, and analysed either as undeveloped egg (whole egg or separated into yolk and albumen) or incubated until start of the hatching process when the chick liver was removed and analysed. High levels of PFAAs were found in all matrixes except albumen. The predominant PFAA was perfluorooctane sulfonate (PFOS), which was found in the μg/g wet weight (ww) range in some samples of cormorant whole egg, yolk and liver and herring gull egg yolk and liver. The average concentration in yolk was 1,506 ng/g ww in cormorant and 589 ng/g ww in herring gull. The average liver concentrations of PFOS were 583 ng/g ww in cormorant and 508 ng/g ww in herring gull. At these concentrations, biochemical effects in the developing embryo or effects on embryo survival cannot be ruled out. For perfluoroalkyl carboxylates (PFCAs), the liver/egg and liver/yolk concentration ratios increased with PFCA chain length in cormorant but not in herring gull, indicating that chain length could possibly affect egg-to-liver transfer of PFCAs and that species differences may exist.  相似文献   
432.
Efficient and sustainable management of rapidly mounting environmental issues has been the focus of current intensive research. The present study aimed to investigate the impact of plant phenological development stage variation on mercury (Hg) tolerance, accumulation, and allocation in two salt marsh macrophytes Triglochin maritima and Scirpus maritimus prevalent in historically Hg-contaminated Ria de Aveiro coastal lagoon (Portugal). Both plant samples and the sediments vegetated by monospecific stands of T. maritima and S. maritimus were collected from reference (R) and sites with moderate (M) and high (H) Hg contamination in Laranjo bay within Ria de Aveiro lagoon. Hg tolerance, uptake, and allocation in T. maritima and S. maritimus, physico-chemical traits (pH, redox potential, and organic matter content) and Hg concentrations in sediments vegetated by these species were impacted differentially by phenological development stages variation irrespective of the Hg contamination level. In T. maritima, Hg concentration increased with increase in Hg contamination gradient where root displayed significantly higher Hg followed by rhizome and leaf maximally at H. However, in S. maritimus, the highest Hg concentration was perceptible in rhizome followed by root maximally at M. Between the two studied plant species, S. maritimus displayed higher Hg tolerance index (depicted by higher plant dry mass allocated to reproductive stage) and higher available Hg at M (during all growth stages) and H (during senescent stage) when compared to T. maritimus. Both plant species proved to be Hg excluder (low root/rhizome–leaf Hg translocation). Additionally, T. maritima also acted as Hg stabilizer while, S. maritimus as Hg accumulator. It can be inferred from the study that (a) the plant phenological development stage variations significantly influenced plant Hg sensitivity by impacting sediment chemistry, plant growth (in terms of plant dry mass), Hg accumulation, and its subsequent allocation capacity, contingent to Hg contamination gradient; (b) S. maritimus accumulated higher Hg but restricted its translocation to above-ground part using exclusion process at both M and H due to its accelerated growth during Hg-tolerant reproductive/metabolically active phenological development stage greater than its counterpart T. maritima; and (c) the studied salt marsh plants although hailed from the same C3 and monocot group did not necessarily display similar phenotypic plasticity and behavior towards Hg-contaminated scenario during their life cycle.  相似文献   
433.
The water disinfecting behavior of silver-modified clinoptilolite–heulandite rich tuff (ZSAg) as an antibacterial agent against coliform microorganisms from water in a continuous mode was investigated. Silver recovery from the disinfected effluents by the sodium-modified clinoptilolite–heulandite rich tuff (ZSNa) was also considered. Escherichia coli (ATCC 8739) and total coliform microorganisms, as indicators of microbiological contamination of water, were chosen to achieve the disinfection of synthetic wastewater or municipal wastewater. Ammonium (NH4+) and chloride (Cl) ions were added to the synthetic wastewater as an interfering chemical species on the disinfection processes. The antibacterial activity of the ZSAg as a bactericide was measured by the coliform concentration as evaluated by the APHA method. The amount of silver in the disinfected effluents was determined using atomic absorption spectroscopy. The inactivation of the ZSAg was calculated from the breakthrough curves based on the model reported by Gupta et al. It was found that when the silver concentration in the effluent is less than 0.6 μg/mL, the bacterial survival percentage increased and the volume of disinfected water diminished. The total silver amounts found in the effluent at the end of the disinfection processes varied depending on the water treated (synthetic or municipal wastewater). The presence of NH4+ ions in synthetic wastewater influent notably improved the disinfected water volume (zero NVC/100 mL), in comparison to the disinfection of the same influent without NH4+ ions. A contrary water disinfection behavior was observed in the presence of Cl ions. The silver recovery does not depend on the mass of the sodium zeolitic bed according with the wastewater to be treated (synthetic or municipal wastewater) and the presence of NH4+ or Cl ions in the influent also influenced the silver recovery from wastewater. The ZSNa did not have antibacterial activity. Therefore the amount of bactericide agent (silver-modified natural zeolite), coliform microorganisms from water (E. coli or consort of coliform microorganisms) as well as the water quality (synthetic wastewater or municipal wastewater) influenced both the disinfection process and the silver recovery in a column system.  相似文献   
434.
435.
The influence of intact (FLT) and photomodified (phFLT) fluoranthene (0.05, 0.5 and 5 μmol l−1) and herbicide Basagran (5, 20, 35 and 50 nmol l−1) on the germination, growth of seedlings and photosynthetic processes in pea plants (Pisum sativum L., cv. Garde) was investigated. The germination was significantly inhibited already by the lowest concentration (0.05 μmol l−1) of FLT and phFLT, while Basagran caused inhibition only in higher concentrations (35 and 50 nmol l−1). The growth of roots was significantly inhibited by higher concentration 5 μmol l−1 of both FLT and phFLT and the shoot of seedlings was significantly influenced only by photomodified form. The length of root and shoot was inhibited already by concentration 5 nmol l−1 of Basagran. Organic compounds applied on chloroplasts suspension influenced primary photochemical processes of photosynthesis. In chlorophyll fluorescence parameters, the significant increase of F0 values and the decrease of FV/FM and ΦII values by application of FLT (0.5 and 5 μmol l−1) and phFLT (0.05, 0.5 and 5 μmol l−1) was recorded. The maximum capacity of PSII (FV/FM) was influenced by the highest (50 nmol l−1) and the effective quantum yield of PSII (ΦII) already by the lowest (5 nmol l−1) concentration of Basagran. Hill reaction activity decreased and was significantly inhibited by higher concentration (0.5 and 5 μmol l−1) of FLT and phFLT and already by the lowest concentration (5 nmol l−1) of Basagran.  相似文献   
436.
Kovács A  Mammen UC  Wernham CV 《Ambio》2008,37(6):408-412
Sixty-four percent of the 56 raptor and owl species that occur in Europe have an unfavorable conservation status. As well as requiring conservation measures in their own right, raptors and owls function as useful sentinels of wider environmental "health," because they are widespread top predators, relatively easy to monitor, and sensitive to environmental changes at a range of geographical scales. At a time of global acknowledgment of an increasing speed of biodiversity loss, and new, forward-looking and related European Union biodiversity policy, there is an urgent need to improve coordination at a pan-European scale of national initiatives that seek to monitor raptor populations. Here we describe current initiatives that make a contribution to this aim, particularly the current "MEROS" program, the results of a questionnaire survey on the current state of national raptor monitoring across 22 BirdLife Partners in Europe, the challenges faced by any enhanced pan-European monitoring scheme for raptors, and some suggested pathways for efficiently tapping expertise to contribute to such an initiative.  相似文献   
437.
Paper recycling is an environmental important activity that is carried out in all the countries, but during the recycling process a paper waste is produced. Generally these wastes are placed in landfill sites but it is possible to profit it as secondary fuel and raw material in manufacture furnaces.

In this work the combustion of the waste papers with cement and ceramic raw material has been studied with the objective to analyse the interaction of these substances with the emitted pollutants like PAHs and PCDD/Fs.

The results of the study show that the presence of inorganic material produces an increment in the lighter PAH emission but chlorinated compounds are not affected. The PCDD/F emission level found in the combustion of this waste is quite low compared with other wastes subjected to similar conditions.  相似文献   

438.
Biodegradability of a partially photo-oxidized pesticide mixture is demonstrated and the effect of photo-Fenton treatment time on growth and substrate consumption of the bacteria Pseudomonas putida CECT 324 is shown. Four commercial pesticides, laition, metasystox, sevnol and ultracid, usually employed in citric orchards in eastern Spain, were chosen for these experiments. The active ingredients are, respectively, dimethoate, oxydemeton-methyl, carbaryl and methidathion. Judging by biomass measurements, dissolved organic carbon measurements and biodegradation efficiency, it may be concluded that 90min相似文献   
439.
Myrtus communis, Arbutus unedo and Retama sphaerocarpa are Mediterranean shrubs widely used in revegetation of semiarid degraded soils. The aim of this work is to study the resistance of these plants to arsenic under controlled conditions, in order to evaluate their potential use in revegetation and/or phytoremediation of As-polluted soils. R. sphaerocarpa showed higher resistance to As than M. communis or A. unedo according to its higher EC50, P status and P/As molar ratio in both, roots and shoots, and the lower increases in lipid peroxidation and decrease of chlorophyll levels in response to arsenic, while the highest arsenate sensitivity was obtained for A. unedo. Arsenic was mainly retained in roots, and, although M. communis accumulated higher arsenic amounts than the other two species, R. sphaerocarpa showed the highest root to shoot transfer. Most of the studied parameters (chlorophylls, MDA and total thiols) showed significant correlation with arsenic concentration in roots and leaves of plants, so they can be useful indexes in the diagnosis of arsenic toxicity in these species. According to our results, both M. communis and R. sphaerocarpa could be used in the revegetation of moderately arsenic contaminated sites.  相似文献   
440.
In this work, 24-h PM10 samples were collected in Rio de Janeiro, Brazil, and analysed for trace elements (Cd, Ce, Cu, La, Mo, Ni, Pb, Pd, Rh, Sb and Sn). The sampling was carried out at five locations (Bonsucesso; Centro, downtown city; Copacabana; Nova Igua?u and Sumaré) with different traffic densities and anthropogenic activities. An analytical method based on the EPA method for the determination of trace elements in airborne particulate matter (PM), using ultrasonic-assisted extraction and inductively coupled plasma mass spectrometry (ICP-MS) was applied. Our results suggest that vehicular traffic is the most important source of environmental pollution at the studied sites. The presence of Mo, Pd and Rh in the analysed filters reflects an additional source of pollution caused by the erosion and deterioration of automotive catalytic converters.  相似文献   
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