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551.
This paper examines the viability of using Canoparmelia texana lichen species as a bioindicator of air pollution by radionuclides and rare earth elements (REEs) in the vicinity of a tin and lead industry. The lichen and soil samples were analyzed for uranium, thorium and REEs by instrumental neutron activation analysis. The radionuclides 226Ra, 228Ra and 210Pb were determined either by Gamma-ray spectrometry (GRS) (soils) or by radiochemical separation followed by gross alpha and beta counting using a gas flow proportional counter (lichens). The lichens samples concentrate radionuclides (on the average 25-fold higher than the background for this species) and REEs (on the average 10-fold higher), therefore they can be used as a fingerprint of contamination by the operation of the tin industry.  相似文献   
552.

Background, aim and scope  

A new approach towards monuments, considering them as a passive sampler of pollution, is presented. Cultural Heritage objects suffer daily the damages of environmental pollution, especially in those areas interested by heavy traffic. Since monuments undergo only periodic conservation or maintenance works, surfaces are able to accumulate atmospheric deposit and to record changes in its composition. An optimised analytical protocol was developed in order to quantify platinum and rhodium at trace level on surfaces. The two elements have become tracers of automobile emissions in recent years, since the introduction of catalytic converters, and could have catalytic effects on the decay reactions of natural and artificial stone materials. As a first case study, the cement mortar surfaces of a twentieth century monument, the Camerlata Fountain, in Como (Italy) were investigated.  相似文献   
553.
Arsenic speciation in marine fish and shellfish from American Samoa   总被引:1,自引:0,他引:1  
We speciated arsenic compounds in marine fish and shellfish from two islands of the United States Territory of American Samoa in the South Pacific, and found that inorganic arsenic occurred as a minor fraction. The proportion of inorganic arsenic was generally far below the levels of prevailing assumptions typically used in human health risk assessments when only total arsenic is analysed. Fish and shellfish were collected from Tutuila and Ofu between May 2001 and March 2002 (n=383 individual specimens, with 117 composites); sites were selected based on habitat type and were representative of those frequented by local fishers. These islands have moderately developed reef fish fisheries among artisanal fishers, are far removed from any industrial or mining sources of arsenic, and presented an opportunity to study arsenic variations in marine biota from un-impacted environments. Target species were from various trophic levels and are among those frequently harvested for human consumption. We found evidence that arsenic concentrated in some marine species, but did not tend to follow classic trophic patterns for biomagnification or bioaccumulation. For the majority of samples, inorganic arsenic was less than 0.5% of total arsenic, with only a few samples in the range of 1-5%, the latter being mollusks which are recognized to have unusually high arsenic levels in general. This work supports the importance of speciation analysis for arsenic, because of the ubiquitous occurrence of arsenic in the environment, and its variable toxicity depending on chemical form.  相似文献   
554.
The activated sludge process is performed by a variable and mixed community of microorganisms in an aerobic aquatic environment, in which bacteria constitute the majority and represent the main microorganisms responsible for the degradation process in a plant. In this work, we monitored bacterial charge in different wastewater treatment plants by flow cytometry, also evaluating chlorination effects on bacterial viability, both by flow cytometry and traditional plate counts. Maximum values of bacterial charge were registered in the aeration tank of all plants monitored. Cell viability did not show significant differences (p > 0.05) in samples collected in "before chlorination" and "wastewater effluent" treatment steps; this suggests that the chlorination was not able to decrease total viable bacterial charge. In this work, we discuss the need to improve microbiological analyses, both in terms of measuring other potential pathogens and of using new methodological approaches in the traditional evaluation of the microbiological quality of effluents.  相似文献   
555.
Data concerning the concentration of dioxins (PCDD/PCDFs), polychlorinated biphenyls (PCBs), metals, metalloids, pesticides and antimicrobials residues are reported for the edible portion of Australian wild and farmed southern bluefin tuna (Thunnus maccoyii). In 2004 wild caught (n=5) and farmed (n=26) southern bluefin tuna (SBT) were collected. The mean concentration of total mercury on a fresh weight (fw) basis was 0.34 mg/kg in wild SBT and 0.31 mg/kg in farmed SBT. Concentrations of dioxins (PCDD/PCDFs) and polychlorinated biphenyls (PCBs) found in wild SBT were extremely low. The mean concentration (fw) of the sum of PCDD/PCDFs and the dioxin-like PCBs was 0.27 pg TEQ/g in wild SBT and 0.61 pg TEQ/g in farmed SBT. Mean PCB total concentration (fw basis) was 0.47 ng/g in wild SBT and 6.60 ng/g in farmed SBT. No detectable residues of any pesticide or antimicrobial compounds were found. All residues detected were within regulatory limits set by the Japanese Competent Authority, the Ministry of Health, Labour and Welfare (MHLW) and the Australian Competent Authority, Food Standards Australia New Zealand (FSANZ). The need for harmonisation of international product integrity procedures for bluefin tunas in international trade is highlighted.  相似文献   
556.
Nuclear power plays an important but controversial role in policies to ensure domestic energy security, fuel poverty reduction and the mitigation of climate change. Our article construes the problem of nuclear power in terms of social discourse, language and public choice; specifically examining the role that metaphors play in the policy domain. We empirically analyze metaphors as framing devices in nuclear energy policy debates in the UK between April 2009 and March 2013, thereby capturing the impact of the Fukushima nuclear disaster in 2011. We employ documentary analysis of major UK national broadsheet and tabloid newspapers, using electronic bibliographic tools to extract the metaphors. We then map these metaphors using a Type Hierarchy Analysis, which examines how elements of the target domain (energy technologies and policies) originate from a different source domain. Type hierarchies identify and categorize metaphors, defining the affectual and emotional responses associated with them, providing us with grounded insight into their role in shaping discourse and as a consequence influence public engagement with energy policy. Our analysis highlights three emergent domains of discourse metaphors and discusses the implications of their deployment. Metaphors were found to be classified into three different categories: Rebirth (Renaissance), Devastation (Apocalypse, Inferno, Genie and Bomb) and Sickness (Addiction and Smoking).  相似文献   
557.
Point Pelee National Park (PPNP) is highly contaminated with dichlorodiphenyltrichloroethane (DDT) and dieldrin due to the historical use of these two persistent organochlorine pesticides. Zero‐valent iron (ZVI) technology with and without amendments has been successfully used in the past to promote organochlorine pesticides degradation in several locations in North America and Europe. In this study, the use of two commercially available ZVI products, DARAMEND® and EHC®, to promote DDT and dieldrin degradation in PPNP's soil and groundwater were investigated. DARAMEND® was applied to PPNP's soil in a laboratory experiment and in an in situ pilot‐scale plot. In both cases, DARAMEND® did not significantly increase DDT or dieldrin degradation in treated soils. The effectiveness of EHC® was tested in a laboratory experiment that simulated the park's groundwater environment using PPNP's pesticide contaminated soil. The result was consistent with the one reported for DARAMEND®, in that there was no significant increase in DDT or dieldrin degradation in any of the samples treated with EHC®. These results demonstrate that both of these ZVI commercially available products are not suitable for in situ remediation at PPNP.  ©2017 Wiley Periodicals, Inc.  相似文献   
558.
Croatia, like many other transition countries has undergone radical changes in its nature protection models. This paper discusses a historical overview, present situation and future possibilities for nature conservation in Croatia. A conservative top-down approach to nature protection was applied in the past in Croatia and is now being replaced by a prevalent bottom-up approach. Social context is crucial to introducing participatory conservation, therefore special concern is given to the perception of the local population towards protected area management in Istria as a case study in Croatia. Survey data were used to assess the conservation knowledge of local populations and their perception towards Protected Areas (PAs), leadership activities and management authorities in Istria County. This paper examines the perceptions of 313 residents living in and around six natural PAs located in Istria. The results revealed a moderate general knowledge about PAs in Istria and environmental issues, and a low awareness of institutions managing PAs, eagerness to participate in the activities of PAs and general support for the conservation cause. Understanding the perception of local residents enables the creation of feasible, long-term strategies for the implementation of participatory conservation. The research identifies the need for greater human, technical and financial efforts to strengthen the management capabilities of local agencies responsible for PAs. The process of participatory conservation optimization in Croatia is underway and world experiences must be observed in order to create a congruent, site-specific model with the best possible results.  相似文献   
559.
Abstract

This paper presents the analysis of ambient air concentrations of 10 carbonyl compounds (aldehydes and ketones) measured in the yards of 87 residences in the city of Elizabeth, NJ, throughout 1999–2001. Most of these residences were measured twice in different seasons; the sampling duration was 48 hr each time. The authors observed higher concentrations for most of the measured carbonyl compounds on warmer days, reflecting larger contributions of photochemical reactions on warmer days. The estimated contributions of photochemical production varied substantially across the measured carbonyl compounds and could be as high as 60%. Photochemical activity, however, resulted in a net loss for formaldehyde. The authors used stepwise multiple linear regression models to evaluate the impact of traffic sources and meteorological conditions on carbonyl concentrations using the data collected on colder days (with lower photochemical activities). They found that the concentrations of formal-dehyde, acetaldehyde, acrolein, propionaldehyde, crotonaldehyde, benzaldehyde, glyoxal, and methylglyoxal significantly decreased with increasing distance between a measured residence and one or more major roadways. They also found significant negative associations between concentrations for most of the measured carbonyl compounds and each of the following meteorological parameters: mixing height, wind speed, and precipitation.  相似文献   
560.
Winfried Schröder  Stefan Nickel  Simon Schönrock  Michaela Meyer  Werner Wosniok  Harry Harmens  Marina V. Frontasyeva  Renate Alber  Julia Aleksiayenak  Lambe Barandovski  Alejo Carballeira  Helena Danielsson  Ludwig de Temmermann  Barbara Godzik  Zvonka Jeran  Gunilla Pihl Karlsson  Pranvera Lazo  Sebastien Leblond  Antti-Jussi Lindroos  Siiri Liiv  Sigurður H. Magnússon  Blanka Mankovska  Javier Martínez-Abaigar  Juha Piispanen  Jarmo Poikolainen  Ion V. Popescu  Flora Qarri  Jesus Miguel Santamaria  Mitja Skudnik  Zdravko Špirić  Trajce Stafilov  Eiliv Steinnes  Claudia Stihi  Lotti Thöni  Hilde Thelle Uggerud  Harald G. Zechmeister 《Environmental science and pollution research international》2016,23(11):10457-10476
For analysing element input into ecosystems and associated risks due to atmospheric deposition, element concentrations in moss provide complementary and time-integrated data at high spatial resolution every 5 years since 1990. The paper reviews (1) minimum sample sizes needed for reliable, statistical estimation of mean values at four different spatial scales (European and national level as well as landscape-specific level covering Europe and single countries); (2) trends of heavy metal (HM) and nitrogen (N) concentrations in moss in Europe (1990–2010); (3) correlations between concentrations of HM in moss and soil specimens collected across Norway (1990–2010); and (4) canopy drip-induced site-specific variation of N concentration in moss sampled in seven European countries (1990–2013). While the minimum sample sizes on the European and national level were achieved without exception, for some ecological land classes and elements, the coverage with sampling sites should be improved. The decline in emission and subsequent atmospheric deposition of HM across Europe has resulted in decreasing HM concentrations in moss between 1990 and 2010. In contrast, hardly any changes were observed for N in moss between 2005, when N was included into the survey for the first time, and 2010. In Norway, both, the moss and the soil survey data sets, were correlated, indicating a decrease of HM concentrations in moss and soil. At the site level, the average N deposition inside of forests was almost three times higher than the average N deposition outside of forests.  相似文献   
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