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501.
Nipper M  Qian Y  Carr RS  Miller K 《Chemosphere》2004,56(6):519-530
Bio- and photo-transformation of two munitions and explosives of concern, 2,6-dinitrotoluene (2,6-DNT) and 2,4,6-trinitrophenol (picric acid) were assessed in spiked marine sediments and water. A sandy and a fine-grained sediment, with 0.25% and 1.1% total organic carbon, respectively, were used for biotransformation assessments at 10 and 20 degrees C. Sterilized sediments were used as controls for biotic vs. abiotic transformation. Transformation products were analyzed by HPLC, GC/MS and LC/MS. Biotransformation in sediments started soon after the initial contact of the chemicals with the sediments and proceeded for several months, with rates in the following sequence: fine-grain at 20 degrees C > fine-grain at 10 degrees C > sand at 20 degrees C > sand at 10 degrees C. The biotransformation paths seemed to be similar for all conditions. The major biotransformation product of 2,6-DNT was 2-amino-6-nitrotoluene (2-A-6-NT). 2-Nitrotoluene (2-NT) and other minor components, including N,N-dimethyl-3-nitroaniline, benzene nitrile, methylamino-2-nitrosophenol and diaminophenol, were also identified. After more prolonged incubation these chemicals were replaced by high molecular weight polymers. Several breakdown products of picric acid were identified by GC/MS, including 2,4-dinitrophenol, amino dinitrophenols, 3,4-diamino phenol, amino nitrophenol and nitro diaminophenol. Photo-transformation of 2,6-DNT and picric acid in seawater was assessed under simulated solar radiation (SSR). No significant photolysis of picric acid in seawater was observed for up to 47 days, but photo-transformation of 2,6-DNT began soon after the initial exposure to SSR, with 89% being photo-transformed in 24 h and none remaining after 72 h. High molecular weight chemicals were generated, with mass spectra ranging from molecular weight 200-500 compared to 182 for DNT, and the color of the stock solution changed from clear to orange. Complexity of the mass spectra and mass differences among fragments suggest that multiple polymers were produced and were co-eluting during the LC/MS analyses.  相似文献   
502.
Within the initiatives for poliomyelitis eradication by WHO, Italy activated an environmental surveillance (ES) in 2005. ES complements clinical Acute Flaccid Paralysis (AFP) surveillance for possible polio cases, detects poliovirus circulation in environmental sewage, and is used to monitor transmission in communities. In addition to polioviruses, the analyses comprised: (i) the monitoring of the presence of non-polio enteroviruses in sewage samples and (ii) the temporal and geographical distribution of the detected viruses. From 2009 to 2015, 2880 sewage samples were collected from eight cities participating in the surveillance. Overall, 1479 samples resulted positive for enteroviruses. No wild-type polioviruses were found, although four Sabin-like polioviruses were detected. The low degree of mutation found in the genomes of these four isolates suggests that these viruses have had a limited circulation in the population. All non-polio enteroviruses belonged to species B and the most frequent serotype was CV-B5, followed by CV-B4, E-11, E-6, E-7, CV-B3, and CV-B2. Variations in the frequency of different serotypes were also observed in different seasons and/or Italian areas. Environmental surveillance in Italy, as part of the ‘WHO global polio eradication program’, is a powerful tool to augment the polio surveillance and to investigate the silent circulation or the re-emergence of enteroviruses in the population.  相似文献   
503.
The paper draws results from a review of literature to examine the strengths and weaknesses of the integrated environmental assessment framework in Canada with respect to the inclusion of health impact assessment. Insights include the legislative nature, rigid structure and priority for the natural environment that may restrict progress and the pool of government agencies that need to be convinced of the benefits of health impact assessment that may provide a strong structure for compliance in the long term.  相似文献   
504.
We examined the relationships of humanactivity, bird communities, and plant communities along theland-water interface of Lake Texoma, a large human-madereservoir on the Texas-Oklahoma border. Measurements ofhuman activity, plant surveys, and bird surveys wereperformed at 40 paired transects, one with humandisturbance, the other undisturbed. Both principalcomponents and correspondence analyses of bird-survey dataseparated disturbed sites from paired undisturbed sites, andtypical disturbance-tolerant species from those lesstolerant of human activity. Compared to undisturbed sites,disturbed sites tended to have more individual birds persurvey, pavement, and mowed lawns, and less canopy,vegetation volume, and vegetation vertical diversity. Aprincipal components analysis of quantitative disturbancemeasurements revealed that most bird and plant measures werehighly correlated with the first disturbance component. However, the correlation between birds and human activitywas much stronger than that between birds and plants, orbetween plants and disturbance. Our data suggest that bird-species composition is regulated more by human activity thanby plant-community composition. Also, in this system, birdcommunities are a better choice than plant communities toindex the effect of human disturbance. To maintain regionaldiversity of both birds and plants, undisturbed areas shouldbe maintained around reservoirs.  相似文献   
505.
The U.S. Department of Energy is conducting a project to accelerate remediation through the use of monitored natural attenuation and enhanced attenuation for chlorinated ethenes in soils and groundwater. Better monitoring practices, improved scientific understanding, and an advanced regulatory framework are being sought through a team effort that engages technology developers from academia, private industry, and government laboratories; site cleanup managers; stakeholders; and federal and state regulators. The team works collaboratively toward the common goals of reducing risk, accelerating cleanup, reducing cost, and minimizing environmental disruption. Cutting‐edge scientific advances are being combined with experience and sound environmental engineering in a broadly integrated and comprehensive approach that exemplifies socalled “third‐generation R&D.” The project is potentially a model for other cleanup activities. © 2004 Wiley Periodicals, Inc.  相似文献   
506.
We synthesized nine studies that examined the influence of land use at different spatial scales in structuring biotic assemblages and stream channel characteristics in southeastern Minnesota streams. Recent studies have disagreed about the relative importance of catchment versus local characteristics in explaining variation in fish assemblages. Our synthesis indicates that both riparian- and catchment-scale land use explained significant variation in water quality, channel morphology, and fish distribution and density. Fish and macroinvertebrate assemblages can be positively affected by increasing the extent of perennial riparian and upland vegetation. Our synthesis is robust; more than 425 stream reaches were examined in an area that includes a portion of three ecoregions. Fishes ranged from coldwater to warmwater adapted. We suggest that efforts to rehabilitate stream system form and function over the long term should focus on increasing perennial vegetation in both riparian areas and uplands and on managing vegetation in large, contiguous blocks. Minnesota Cooperative Fish and Wildlife Research Unit is jointly sponsered by U.S. Geological Survey Biological Resources Division, the University of Minnesota, The Minnesota Department of Natural Resources, and the Wildlife Management Institute.  相似文献   
507.
This article presents the findings of a survey of farmers' markets customers in the Niagara region of Ontario, Canada. The recent growth of farmers' markets in North America and the association of these markets with local food systems development provoke examination to gain insights into consumer motivations for patronizing these markets, and to then reflect on their potential role within locally oriented and sustainable food production systems. The survey carried out on customers of three Niagara region farmers' markets corroborates previous studies that noted that socioeconomic and cultural factors such as the importance of food freshness, support of local farmers and the local farm economy, and social interaction—embeddedness—are key expressions of people's support and interest in farmers' markets. This work serves to heighten our understanding of consumer attitudes toward direct marketing via farmers' markets, yields useful speculation about these markets and their roles in sustainable local food systems progress, and also raises critical questions about such customer patronage and associated farmers' markets potential in local food system development.  相似文献   
508.
ABSTRACT: The implementation of various bioretention systems was analyzed, including rain gardens, vegetated swales, trenches, and infiltration basins in the St. Francis subdivision, Cross Plains, Wisconsin. Through the examination of archival data and interviews with key participants, it was found that although regulatory and political pressures encouraged the inclusion of bioretention, current standards for storm water management prevailed. The developers had to meet both existing requirements and anticipated rules requiring infiltration. As a result, bioretention systems simply supplemented, rather than replaced, traditional storm water practices. The confusion surrounding dual standards contributed to substantial delays in the negotiations among relevant stakeholders in the watershed. It is concluded that the St. Francis subdivision serves as both a cautionary tale and a bioretention success story. As a caution, this situation demonstrates the need for careful review and refinement of existing storm water ordinances to incorporate water quality improvement technologies, such as bioretention. The demonstrated success of the St. Francis development, however, is that it became a positive prototype for best management storm water practices elsewhere in the region. In addition, the water quality monitoring data from the site has contributed to development of a new county ordinance, the first in Wisconsin to address both quantity and quality of storm water runoff.  相似文献   
509.
Organizations that manage property that poses risks for surrounding communities need to practice stewardship. Stewardship is defined as carrying out the responsibility to manage land and facilities in a sustainable manner, while being accountable to others who have a stake in those resources. This article reviews six case studies of organizational stewardship and derives a set of five lessons learned, along with four challenges. Lessons include developing stewardship goals, good stakeholder relationships, multiple approaches to safety, and encouraging innovation and stable funding. Challenges include bureaucratic processes, burdensome regulations, organizational continuity, and inter‐organizational cooperation. These crosscutting lessons learned about how to achieve success or avoid failure in long‐term management of resources can be applied to all types of public and private agencies, including the long‐term management of environmental contamination. © 2003 Wiley Periodicals, Inc.  相似文献   
510.
This article presents a database developed to determine the potential reuse of contaminated sites for primarily ecologically and culturally based activities. The database consists of 172 quantitative and qualitative measures of on‐site land suitability, ecological, cultural, and recreational value, and off‐site suitability, economic, and demographic information. Using sites owned by the U.S. Department of Energy (DOE) as a case study, the article evaluates the quality of available data and suggests ways of using it for planning ecologically sensitive remediation activities and future land use. This type of database can be developed and used by anyone who needs to select, review, or evaluate site remediation and future land use options. Also discussed are the challenges associated with compiling and using data that has been generated by many sources over several years. © 2003 Wiley Periodicals, Inc.  相似文献   
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