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1.
An intrinsic biodegradation study involving the design and implementation of innovative environmental diagnostic tools was conducted to evaluate whether monitored natural attenuation (MNA) could be considered as part of the remedial strategy to treat an aerobic aquifer contaminated with 1,4-dioxane and trichloroethene (TCE). In this study, advanced molecular biological and stable isotopic tools were applied to confirm in situ intrinsic biodegradation of 1,4-dioxane and TCE. Analyses of Bio-Trap? samplers and groundwater samples collected from monitoring wells verified the abundance of bacteria and enzymes capable of aerobically degrading TCE and 1,4-dioxane. Furthermore, phospholipid fatty acid analysis with stable isotope probes (PLFA-SIP) of the microbial community validated the ability for microbial degradation of TCE and 1,4-dioxane. Compound specific isotope analysis (CSIA) of groundwater samples for TCE resulted in δ(13)C values that indicated likely biodegradation of TCE in three of the four monitoring wells sampled. Results of the MNA evaluation showed that enzymes capable of aerobically degrading TCE and 1,4-dioxane were present, abundant, and active in the aquifer. Taken together, these results provide direct evidence of the occurrence of TCE and 1,4-dioxane biodegradation at the study site, supporting the selection of MNA as part of the final remedy at some point in the future.  相似文献   
2.
We studied the binding of Cu(II) to humic acids and fulvic acids extracted from two horizons of an ombrotrophic peat bog by metal titration experiments at pH 4.5, 5.0, 5.5, and 6.0 and 0.1 M KNO3 ionic strength. Free metal ion concentrations in solution were measured using an ion selective electrode. The amounts of base required to maintain constant pH conditions were recorded and used to calculate H+/Cu2+ exchange ratios. The amount of Cu(II) bound to the humic fractions was greater than the amount bound to the fulvic fractions and only at the highest concentrations of metal ion the amount of Cu(II) sorbed by both fractions became equal. The proton to metal ion exchange ratios are similar for all humic substances, with values ranging from 1.0 to 2.0, and decreasing with increased pH. The amount of Cu(II) bound is practically independent of the horizon from which the sample was extracted. The results indicate that the humic substances show similar cation binding behaviour, despite the differences in chemical composition. The copper binding data are quantitatively described with the NICA-Donnan model, which allows to characterize only the carboxylic type binding sites. The values of the binding constants are higher for the humic acids than for the fulvic acids.  相似文献   
3.
In this paper, we divide the communities in Central China into four groups, namely ecological high-poverty communities, non-ecological high-poverty communities, sustainable communities and non-ecological low-poverty communities. We use 2000 and 2006 data for 498 counties to conduct analysis and comparison between sustainable and unsustainable communities in order to define determinants of the development pathways to sustainable communities. The comparison of the variable means between the groups of ecological high-poverty communities and non-ecological high-poverty communities in 2006 indicates that there is no significant difference in the dimensions related to economy, society and environment, with the exception of average output value per industrial enterprise.

The non-ecological low-poverty communities are more likely to have a higher proportion of secondary industry, higher total industrial output value, higher average output value per industrial enterprise and higher intensity of infrastructure construction, compared to the sustainable communities. The factors that determine whether the communities will choose the pathway to sustainable communities are found to be landscape, social conditions of secondary industry and agriculture and economic development level. Hence, the policies that aim at promoting sustainability for the unsustainable communities will have to focus on different strategies and actions for non-ecological high-poverty and non-ecological low-poverty communities.  相似文献   
4.
Boston's Chinatown is an urban community surrounded by businesses, a university, a large medical centre, and an area zoned for “adult entertainment” called the Combat Zone. The overall goal of this exploratory study was to examine the temporal and geographic distribution of street crime in Boston's Chinatown using police crime reports from the years 1988 to 2004. Crime patterns were most notably associated with the presence of the adult entertainment area, known as the Combat Zone. However, despite the decline of adult businesses over the study period, we saw small limited reduction in property and violent crimes, suggesting that the decline of these businesses did not lead to large-scale short-term (<5 years) reductions in crime.  相似文献   
5.
This paper examines the impact of the clean development mechanism (CDM) on China??s progress in building a resource-efficient and environmentally friendly society, referred to as a dual-goal society. It presents China??s CDM activities from the perspective of policy directions, administrative arrangements and capacity building as well as outlines the regional trends and distribution of CDM projects across China??s 30 provinces. Based on regression analysis of 2006?C2009 panel data, the research was able to provide estimates at provincial level of the impacts of CDM activities on China??s CO2 emission intensity, SO2 emission intensity and industrial dust emission intensity. The study concludes that the active CDM projects are mainly located in the less-developed central and west China where they have provided increased opportunities for sustainable development. Furthermore, the successful implementation of CDM projects across the country has significantly decreased the emission intensity of CO2, SO2 and industrial dust, which means that these activities have enhanced China??s ability to build the desired dual-goal society.  相似文献   
6.
Bio‐Trap®–based in situ microcosm studies were conducted to evaluate EHC‐M® stimulated degradation of mono‐, di‐, and trichlorobenzenes in anaerobic groundwater at a site in Michigan. The data show that the EHC‐M® amendment stimulated an overall increase in microbial activity and a shift in the microbial community structure, indicating more reduced conditions. Stable isotope probing with 13C6‐chlorobenzene demonstrated attenuation of chlorobenzene and subsequent separation and characterization of the 12C‐ and 13C‐deoxyribonucleic acid (DNA) fractions were used to identify the attenuating microbes. These data clearly show the participation of an obligate aerobe in the chlorobenzene biodegradation process. Decreases in concentrations of trichlorobenzenes were also observed in comparison to a control. Due to the thermodynamically favorable reducing conditions stimulated by EHC‐M®, the mechanism of degradation of the trichlorobenzenes is presumed to be reductive dehalogenation. However, on the strength of the DNA‐based analysis of microbial community structure, concurrent microaerophilic degradation of chlorobenzene or its metabolites was definitively demonstrated and cannot be ruled out for the other chlorobenzenes. © 2013 Wiley Periodicals, Inc.  相似文献   
7.
Regionally specific sustainability processes that account for diverse environments and populations and that integrate social, economic, political and ecological spheres are being developed in Western Australia. A coordinated commitment to sustainability principles and a participatory philosophy by the state and local governments is necessary. This requires a transformation of the public service, from a director of passive programmes and laws to a facilitator of community projects and outcomes, towards an enabling state. An international participatory paradigm provides an array of concepts and methods for local and regional communities in partnership with government and industry to achieve this. Participatory methodologies are utilised successfully around the globe to create an institutional framework that facilitates a process of dialogue, partnership, networking, learning and managing change. This paper examines the potential contribution of a participatory approach to improve the participatory capacity of regional communities and both local and state governments towards the facilitation of regional sustainability processes.  相似文献   
8.
A sensitive and simple procedure is described for determining the total phenolic/antioxidant levels of olive oil mill wastewater (OMW), using for the first time Co(II)/ethylenediaminetetracetic acid (EDTA)-induced luminol chemiluminescence. Olive oil wastewater samples were tested for their composition in simple phenolic compounds as a function of the extraction system (two- and three-phase centrifugation systems). The results revealed that the three-phase system had a stronger antioxidant activity and a higher total phenolic content than the two-phase system. The relationship between antioxidant values and total phenolic content is also discussed.  相似文献   
9.
Understanding longshore sediment transport (LST) is a prerequisite for designing an effective coastal zone management strategy. The present study estimates the LST along the central west coast of India based on four bulk LST formulae: (1) the Coastal Engineering Research Center (CERC) formula, (2) the Walton and Bruno formula, (3) the Kamphuis formula and (4) the Komar formula. The Delft3D–wave module is used for estimating nearshore waves with measured directional wave data at a water depth of 9 m as the input parameter. Wave data for the validation of the nearshore wave transformation model is measured using the InterOcean S4DW wave gauge. The model results show that waves approach from the south 90 % of the time in a year and that they generate predominantly northerly longshore currents. Upon comparison with the measured data, the findings show that the estimates based on the Kamphuis formula agree with the field data. A high ratio (~1) of the monthly net and gross transport rates indicates that the LST is dominating in one direction in all months except February and July. The study shows that a slight change in the angle of the wave approach during the Asian summer monsoon period (JJAS) can significantly alter the direction and magnitude of the LST. Inter-annual variations in the LST based on the data for 2009 and 2011 show that the variations in the annual net and gross LST rates in different years are less than 7 %.  相似文献   
10.
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