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Monitoring of Phenol in Wastewater Bioremediation by HPLC 总被引:1,自引:0,他引:1
KC Ng G Poi CM Puah V De Castro PL Rogers 《Environmental monitoring and assessment》1997,44(1-3):433-436
Bioremediation emphasizes the detoxification and destruction of toxic substances by microorganisms. Wastewater obtained from an industrial concern was solvent extracted with methyl alcohol and dichloromethane and analysed by GC/MS. Besides phenol, a large variety of organic compounds were detected. Under controlled laboratory conditions, the wastewater was innoculated with a mixed culture of microorganisms specially selected for their abilities to degrade phenol. Samples were collected at regular intervals from the stirred tank bioreactor and analysed for phenol by reverse phase HPLC with a C18 column. Results shows that from an initial phenol concentration of 987 ppm, slightly more than 50% was destroyed within 163 hours. The dry weight of the microorganisms and the plate count (CFU/ml) shows a steady increase from 0.5238 gms to 0.5355 gms and from 1.1E+9 to 1.94E+13 respectively over the same period. This suggested that the phenol was consumed by the microorganisms as the sole carbon source. 相似文献
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Peter A Dewees 《Natural resources forum》1995,19(2):143-152
Forestry and energy policies in Malawi place the blame for the country's high rate of deforestation on the demand for woodfuel. The government has been involved in a range of questionable supply-side initiatives, as well as in a number of interventions in woodfuel markets, with the objective of slowing rates of deforestation. It seeks to encourage farmers to grow woodfuel to meet market demands, and has provided subsidies to do so. The Forest Department has kept prices for firewood from its plantations low, both in order to discourage the market for wood from free resources and because of concerns about the impact of high producer prices on the urban poor. In doing so, the government is less able to rely on the market to provide producers with the incentive to plant trees to meet market demands. In any event, the market accounts for a relatively small proportion of total woodfuel demand. Policies do not distinguish between rural household demands and the specific market demands which are having the greatest impact on deforestation: woodfuel for urban markets, for tobacco curing, and for small industries. These, coupled with the expansion of the estate sector, have had afar greater impact on woodland clearance than rural, subsistence woodfuel demands. Rural household energy demands need to be addressed from a much broader perspective which considers the household's larger needs for tree based products or outputs: income, food, fibre, fodder, soil fertility, as well as for fuel . 相似文献
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Market-based approaches to environmental regulation (such as tradable permits or transferable quotas) are frequently offered
as innovative solutions to many environmental problems. Globally, one of the most well-established forms of this approach
is individual transferable quotas (or ITQs) in fisheries management. Within the natural resource management community, there
is considerable debate over the effects ITQs have on the fishing industry and fisher behavior although this approach is not
well-established in the United States. The previously imposed moratorium on ITQs in the United States has expired and the
2006 reauthorization of the Magnuson-Stevens Act explicitly provides for limited access privileges (LAPs). A variety of fishers,
regulators, and conservation organizations are enthusiastically seeking to introduce ITQ management. With debate over whether
and how ITQs should be used in American fisheries reinvigorated, it is timely to examine the evidence on the social and economic
effects of ITQs in other nations’ fisheries. After briefly summarizing the debate on ITQs, we examine the case of New Zealand,
one of the earliest and longest-lived ITQ-based fisheries regimes. We use multiple data sources and methods to analyze the
extent to which industry consolidation and aggregation has occurred, including surveys of industry participants, expert interviews,
reviews of academic reports and analyses, analysis of trade publications, and direct analysis of quota ownership patterns.
This analysis shows a more complex outcome than recent debates in the ITQ literature would predict. These findings suggest
that policy makers considering ITQs can learn from the experiences of other countries related to key issues such as quota
allocation, aggregation limits, transferability, cost recovery, and resource sustainability when designing ITQ and other LAP
systems. It is also important to explicitly identify economic and social objectives and then carefully design ITQ regimes
to meet these objectives. 相似文献
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