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151.
We investigated the acute impact of trinitrotoluene (TNT) contamination of soil on the aerobic bacterial community composition and function. The contamination of the environment with explosive residues presents a serious problem at sites across the world, with the highly toxic compound TNT being the most widespread explosive contaminant. We investigated the acute impact of trinitrotoluene (TNT) contamination of soil on the aerobic bacterial community composition and function. Soil microcosms were amended with a range of concentrations of TNT for 30 days. A polyphasic approach encompassing culture-independent molecular analysis by DGGE, community-level physiological profiling (CLPP) and cell enumeration revealed that the amendment of soils with TNT resulted in a shift from slower growing k-strategists towards faster growing r-strategists. Pseudomonads became prevalent at high concentrations of TNT. Pollution induced community tolerance (PICT) was observed as TNT concentrations increased. Chemical analyses revealed that TNT was reduced to its amino derivatives, products of reductive microbial transformation. The transformation to amino derivatives decreased at high concentrations of TNT, indicative of inhibition of microbial TNT transformation.  相似文献   
152.
Microbial and plant ecology of a long-term TNT-contaminated site   总被引:1,自引:0,他引:1  
The contamination of the environment with explosive residues presents a serious ecological problem at sites across the world, with the highly toxic compound trinitrotoluene (TNT) the most widespread contaminant. This study examines the soil microbial community composition across a long-term TNT-contaminated site. It also investigates the extent of nitroaromatic contamination and its effect on vegetation. Concentrations of TNT and its metabolites varied across the site and this was observed to dramatically impact on the extent and diversity of the vegetation, with the most heavily contaminated area completely devoid of vegetation. Bryophytes were seen to be particularly sensitive to TNT contamination. The microbial population experienced both a reduction in culturable bacterial numbers and a shift in composition at the high concentrations of TNT. DGGE and community-level physiological profiling (CLPP) revealed a clear change in both the genetic and functional diversity of the soil when soil was contaminated with TNT.  相似文献   
153.
To provide additional evidence that several halogenated organic compounds (HOCs) found in environmental samples are natural and not industrially produced, we analyzed an archived whale oil sample collected in 1921 from the last voyage of the whaling ship Charles W. Morgan. This sample, which pre-dates large-scale industrial manufacture of HOCs, contained two methoxylated polybrominated diphenyl ethers (MeO-PBDEs), five halogenated methyl bipyrroles (MBPs), one halogenated dimethyl bipyrrole (DMBP), and tentatively one dimethoxylated polybrominated biphenyl (diMeO-PBB). This result indicates, at least in part, a natural source of the latter compounds.  相似文献   
154.
The aim of this study was to evaluate different techniques for assessing the availability of polycyclic aromatic hydrocarbons (PAHs) in soil. This was done by comparing the amounts (total and relative) taken up by the earthworm Eisenia fetida with the amounts extracted by solid-phase microextraction (SPME), semi-permeable membrane devices (SPMDs), leaching with various solvent mixtures, leaching using additives, and sequential leaching. Bioconcentration factors of PAHs in the earthworms based on equilibrium partitioning theory resulted in poor correlations to observed values. This was most notable for PAHs with high concentrations in the studied soil. Evaluation by principal component analysis (PCA) showed distinct differences between the evaluated techniques and, generally, there were larger proportions of carcinogenic PAHs (4-6 fused rings) in the earthworms. These results suggest that it may be difficult to develop a chemical method that is capable of mimicking biological uptake, and thus estimating the bioavailability of PAHs.  相似文献   
155.
Throughout 2004, PM(10) concentrations were measured at 10 min intervals at Hazelrigg, a remote location in NW England. The annual mean concentration was 6.1 microg m(-3) and likely origins were determined using directional and particle size characteristics. The fine temporal resolution of the monitoring also allowed several short periods (< 20 h) of persistently high PM(10) concentration to be identified and then 'typed' by event start time, duration, wind direction and particle size characteristics. A series of night time PM(10) anomalies (concentration < 465 microg m(-3)) of no obvious source were identified, and by elimination assumed to have originated from a ground-based fire of particle-rich fodder. A novel methodology combining Stokes' Law with systematic and rigorous modelling of source strength (using ADMS3.2) was developed to locate a possible burn site. The process was limited by the lack of previous modelling studies related to ground-based fires, and also by the capacity of ADMS3.2 to model sub-hourly time-varying emissions and fluctuations in wind speed and direction in the near field. However, modelling did suggest the source was located <400 m SSE of Hazelrigg, and investigation of this area revealed a burn site where tyres and plastic bags were piled nearby. Few studies have combined directional analysis and modelling to locate a source based on sampled data. This innovative methodology could be used by regulatory bodies to investigate the origins of unidentified PM(10) observed within the particle record.  相似文献   
156.
This paper presents an analysis of present and future hydrological conditions at the Forsmark site in Sweden, which has been proposed as the site for a geological repository for spent nuclear fuel. Forsmark is a coastal site that changes in response to shoreline displacement. In the considered time frame (until year 10 000 ad), the hydrological system will be affected by landscape succession associated with shoreline displacement and changes in vegetation, regolith stratigraphy, and climate. Based on extensive site investigations and modeling of present hydrological conditions, the effects of different processes on future site hydrology are quantified. As expected, shoreline displacement has a strong effect on local hydrology (e.g., groundwater flow) in areas that change from sea to land. The comparison between present and future land areas emphasizes the importance of climate variables relative to other factors for main hydrological features such as water balances.  相似文献   
157.
158.
This paper studies how fisheries services are classified in the World Trade Organization (WTO) framework for trade in services and discusses the potential impact of unclear classifications. The WTO plays a key role in regulation and assessment in the area of trade in services, mainly due to the General Agreement on Trade in Services (GATS), which contains the only set of multilateral rules managing such trade internationally. The purpose of GATS is to create a credible and reliable system of international trade rules that ensures fair treatment of all participants. Through negotiations, individual countries establish commitments to provide market access and limiting national treatment in various service sectors. During such negotiations, the classification of services is a prerequisite to ensure unambiguous and comparable commitments. However, the classification list used by the WTO, namely the W/120, is based on, and corresponds to, old versions of other classification lists, leading to unclear classifications. This lack of clarity in sectoral classifications makes policy analysis unnecessarily difficult and creates a risk that trade agreements may be interpreted differently by different parties.  相似文献   
159.
Birds of prey, owls and falcons are widely used as sentinel species in raptor biomonitoring programmes. A major current challenge is to facilitate large-scale biomonitoring by coordinating contaminant monitoring activities and by building capacity across countries. This requires sharing, dissemination and adoption of best practices addressed by the Networking Programme Research and Monitoring for and with Raptors in Europe (EURAPMON) and now being advanced by the ongoing international COST Action European Raptor Biomonitoring Facility. The present perspective introduces a schematic sampling protocol for contaminant monitoring in raptors. We provide guidance on sample collection with a view to increasing sampling capacity across countries, ensuring appropriate quality of samples and facilitating harmonization of procedures to maximize the reliability, comparability and interoperability of data. The here presented protocol can be used by professionals and volunteers as a standard guide to ensure harmonised sampling methods for contaminant monitoring in raptors.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01341-9) contains supplementary material, which is available to authorized users.  相似文献   
160.
Regional Environmental Change - Protection of natural or semi-natural ecosystems is an important part of societal strategies for maintaining biodiversity, ecosystem services, and achieving overall...  相似文献   
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