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41.
Industrial ecology is a systemic organizing framework for the many facets of environmental management. It views the industrial world as a natural system, embedded in local ecosystems and the global biosphere. It provides a fundamental understanding of the value of modeling the industrial system on ecosystems to achieve sustainable environmental performance. In this article, the author shows how it offers powerful tools of analysis that complement and enhance those offered by such approaches as Total Quality Environmental Management or pollution prevention.  相似文献   
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Gray whales are coastal migratory baleen whales that are benthic feeders. Most of their feeding takes place in the northern Pacific Ocean with opportunistic feeding taking place during their migrations and residence on the breeding grounds. The concentrations of organochlorines and trace elements were determined in tissues and stomach contents of juvenile gray whales that were taken on their Arctic feeding grounds in the western Bering Sea during a Russian subsistence harvest. These concentrations were compared to previously published data for contaminants in gray whales that stranded along the west coast of the US during their northbound migration. Feeding in coastal waters during their migrations may present a risk of exposure to toxic chemicals in some regions. The mean concentration (standard error of the mean, SEM) of sigmaPCBs [1400 (130) ng/g, lipid weight] in the blubber of juvenile subsistence whales was significantly lower than the mean level [27,000 (11,000) ng/g, lipid weight] reported previously in juvenile gray whales that stranded in waters off the west coast of the US. Aluminum in stomach contents of the subsistence whales was high compared to other marine mammal species, which is consistent with the ingestion of sediment during feeding. Furthermore, the concentrations of potentially toxic chemicals in tissues were relatively low when compared to the concentrations in tissues of other marine mammals feeding at higher trophic levels. These chemical contaminant data for the subsistence gray whales substantially increase the information available for presumably healthy animals.  相似文献   
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Within a few years all domestic wastewater effluents in the United States will be subjected to a minimum of a properly operated primary and secondary treatment process. This implies a very high degree of removal of the more readily biologically degradable material as measured by the BOD test. This practice will to a large degree negate the value of the BOD test as a pollution parameter. Organic carbon appears to be a more suitable means for determining the strength of a wastewater or for controlling the operation of physical and chemical treatment processes. Studies were conducted to determine the effect of time of passage on the ratio of organic carbon to BOD, COD and carbohydrate. The ratio was found to vary with both time and the state of the sample. The carbon content was reduced to a lesser degree than the other parameters. Organic carbon content appears to correlate better with COD than with BOD. The efficiency of a chemical precipitation process can be determined on the basis of organic carbon removal.  相似文献   
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This study contends that climatic events such as storms and floods may significantly impact on cost of protection through climate proofing of housing structures along the Atlantic coastal zone in the Southwest region of Cameroon. Household level protection is purposely examined on the rationale that current protective efforts constitute the building blocks for long-term adaptation. Examining the determinants of the cost of current protection stands good stead to better inform policy to promote future adaptation to climatic stress. Hence, from a research sample of 400 households, the study estimates a function that relates household-level protection costs to their characteristics. Sixty-four percent of the homes studied have been hit at least once by strong winds, and an average of 2 times in the last 5 years, and 36% of houses have once been hit by storm surge from the sea nearby. With an average monthly income of 120.000 FCFA (US285), the coastal residents spend on average 145,500 FCFA (US 285), the coastal residents spend on average 145,500 FCFA (US 346) in preparation against floods. The statistical estimates of the cost function reveal significant positive signs, implying that the experiences and location of homes within floodplain increases the cost of protection no matter the structural characteristics of the house. The study observes that the proximity to the coast and in flood plains significantly increases the cost of protection, and the ability to invest in preventive measures and climate proofing housing structures increase as individual income grows. The findings indicate the need for improvement of monitoring and forecasting systems for floods, intensification of awareness and proper urban planning. The policy implications are reinforced by the low incomes of most residents, as this calls for external assistance through transfer of planning skills, capital and public options to reinforce the resilience and choices made at the household level.  相似文献   
46.
Marine protected areas (MPAs) are being promoted in Tanzania to mitigate the drivers of ecosystem change such as overfishing and other anthropogenic impacts on marine resources. The effectiveness of MPAs in managing those drivers was assessed in three ecological zones, seafront, mangrove, and riverine of Mnazi Bay Marine Park, using Participatory Community Analysis techniques, questionnaire survey, checklist and fishery resource assessment methods. Eleven major drivers of ecosystem change were identified. Resource dependence had a major effect in all ecological zones of the park. The results indicated that the park’s legislations/regulations, management procedures, and conservation efforts are reasonably effective in managing its resources. The positive signs accrued from conservation efforts have been realized by the communities in terms of increased catch/income, awareness and compliance. However, some natural and anthropogenic drivers continued to threaten the park’s sustainability. Furthermore, implementation of resource use and benefit sharing mechanisms still remained a considerable challenge to be addressed.  相似文献   
47.
The great majority of China's developing towns will be extensions of already existing villages. With the prospect of hundreds of millions of Chinese farmers projected to leave their villages to become industrial workers in new and expanded towns within the next few years, new challenges will be faced. As expansion and modernization progress, this development moves from the traditional village model that operates not far from resource sustainability to increasingly unsustainable patterns of commerce, urban development, and modern life. With such an unprecedented mass migration and transformation, how can Chinese culture survive? What is to become of the existing million plus agricultural villages? How can these massively unsustainable new industrial towns survive? In the European Commission sponsored research program SUCCESS, researchers worked from the scale of the Chinese village to find viable answers to these questions.  相似文献   
48.
Volatile organic chloramines are reported as the disinfection byproducts during chlorination or chloramination.However,ClO_2,as an important alternative disinfectant for chlorine,was not considered to produce halogenated amines.In the present work,volatile organic chloramines including(CH_3)_2 NCl and CH_3 NCl_2 were found to be generated during the reaction of ClO_2 and the dye pollutants.(CH_3)_2 NCl was the dominant volatile DBP to result from ClO_2 treated all four dye pollutants including Methyl Orange,Methyl Red,Methylene Blue and Malachite Green,with molar yields ranging from 2.6% to 38.5% at a ClO_2 to precursor(ClO_2/P) molar ratio of 10.HOCl was identified and proved to be the reactive species for the formation of (CH_3)_2 NCl,which implied(CH_3)_2 NCl was transformed by a combined oxidation of ClO_2 and hypochlorous acid.(CH_3)_2 NCl concentrations in the ppb range were observed when real water samples were treated by ClO_2 in the presence of the dye pollutants.The results suggest that these azo dyes are one of the significant precursors for the formation of HOCl during ClO_2 treatment and that organic chloramines should be considered in ClO_2 disinfection chemistry and water treatment.  相似文献   
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