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531.
Agricultural recycling of treatment-plant sludge: a case study for a vegetable-processing factory 总被引:1,自引:0,他引:1
The present study evaluated the possibility of using the sludge produced by a vegetable-processing factory in agriculture. The sludge was amended with a soil mixture (i.e., a mixture of sand, soil, and manure) and was applied at 0, 165, 330, 495 and 660 t/ha to promote the growth of cucumbers. The effects of various sludge loadings on plant growth were assessed by counting plants and leaves, measuring stem lengths, and weighing the green parts and roots of the plants. We also compared heavy metal uptake by the plants for sludge loadings of 330, 495, and 660 t/ha with various recommended standards for vegetables. Our results showed that plant growth patterns were influenced to some extent by the sludge loadings. In general, the number of leaves, stem length, and dry weight of green parts exhibited a pronounced positive growth response compared with an unfertilized control, and root growth showed a lesser but still significant response at sludge loadings of 165 and 330 t/ha. The sludge application caused no significant increase in heavy metal concentrations in the leaves, though zinc (Zn) and iron (Fe) were found at elevated concentrations. However, despite the Zn and Fe accumulation, we observed no toxicity symptoms in the plants. This may be a result of cucumber's tolerance of high metal levels. 相似文献
532.
Snelder TH Leathwick JR Dey KL Rowden AA Weatherhead MA Fenwick GD Francis MP Gorman RM Grieve JM Hadfield MG Hewitt JE Richardson KM Uddstrom MJ Zeldis JR 《Environmental management》2007,39(1):12-29
We describe here the development of an ecosystem classification designed to underpin the conservation management of marine environments in the New Zealand region. The classification was defined using multivariate classification using explicit environmental layers chosen for their role in driving spatial variation in biologic patterns: depth, mean annual solar radiation, winter sea surface temperature, annual amplitude of sea surface temperature, spatial gradient of sea surface temperature, summer sea surface temperature anomaly, mean wave-induced orbital velocity at the seabed, tidal current velocity, and seabed slope. All variables were derived as gridded data layers at a resolution of 1 km. Variables were selected by assessing their degree of correlation with biologic distributions using separate data sets for demersal fish, benthic invertebrates, and chlorophyll-a. We developed a tuning procedure based on the Mantel test to refine the classification's discrimination of variation in biologic character. This was achieved by increasing the weighting of variables that play a dominant role and/or by transforming variables where this increased their correlation with biologic differences. We assessed the classification's ability to discriminate biologic variation using analysis of similarity. This indicated that the discrimination of biologic differences generally increased with increasing classification detail and varied for different taxonomic groups. Advantages of using a numeric approach compared with geographic-based (regionalisation) approaches include better representation of spatial patterns of variation and the ability to apply the classification at widely varying levels of detail. We expect this classification to provide a useful framework for a range of management applications, including providing frameworks for environmental monitoring and reporting and identifying representative areas for conservation. 相似文献
533.
Burger J Gochfeld M Powers CW Kosson DS Halverson J Siekaniec G Morkill A Patrick R Duffy LK Barnes D 《Journal of environmental management》2007,85(1):232-244
It is increasingly clear that a wide range of stakeholders should be included in the problem formulation phase of research aimed at solving environmental problems; indeed the inclusion of stakeholders at this stage has been formalized as an integral part of ecological risk assessment. In this paper, we advocate the additional inclusion of stakeholders in the refinement of research methods and protocols and in the execution of the research, rather than just at the final communication and reporting phase. We use a large study of potential radionuclide levels in marine biota around Amchitka Island as a case study. Amchitka Island, in the Aleutian Island Chain of Alaska, was the site of three underground nuclear tests (1965-1971). The overall objective of the biological component of the study was to collect a range of marine biota for radionuclide analysis that could provide data for assessing current food safety and provide a baseline for developing a plan to monitor human and ecosystem health in perpetuity. Stakeholders, including regulators (State of Alaska), resource trustees (US Fish and Wildlife Service, State of Alaska), representatives of the Aleut and Pribilof Island communities, the Department of Energy (DOE), and others, were essential for plan development. While these stakeholders were included in the initial problem formulation and approved science plan, we also included them in the refinement of protocols, selection of bioindicators, selection of a reference site, choice of methods of collection, and in the execution of the study itself. Meetings with stakeholders resulted in adding (or deleting) bioindicator species and tissues, prioritizing target species, refining sampling methods, and recruiting collection personnel. Some species were added because they were important subsistence foods for the Aleuts, and others were added because they were ecological equivalents to replace species deleted because of low population numbers. Two major refinements that changed the research thrust were (1) the inclusion of Aleut hunters and fishers on the biological expedition itself to ensure that subsistence foods and methods were represented, and (2) the addition of a fisheries biologist on a NOAA research trawler to allow sampling of commercial fishes. Although the original research design called for the collection of biota by Aleut subsistence fishermen, and by a commercial fishing boat, the research was modified with continued stakeholder input to actually include Aleuts and a fisheries biologist on the expeditions to ensure their representation. The inclusion of stakeholders during the development of protocols and the research itself improved the overall quality of the investigation, while making it more relevant to the interested and affected parties. Final responsibility for the design and execution of the research and radionuclide analysis rested with the researchers, but the process of stakeholder inclusion made the research more valuable as a source of credible information and for public policy decisions. 相似文献
534.
KY-3型聚合物处理炼厂含油污水研究 总被引:1,自引:0,他引:1
运用KY -3型阳离子聚合物与无机絮凝剂复配对炼厂含油污水处理进行了研究。结果表明 :KY -3型阳离子聚合物的分子量、加入浓度及污水 pH值、污水温度等对处理效果影响较大 ,当阳离子聚合物相对分子量为120万时 ,处理效果随聚合物加量增大、污水温度及 pH升高而增强 相似文献
535.
Kiyoko M. Gotanda Katrine Turgeon Donald L. Kramer 《Behavioral ecology and sociobiology》2009,63(11):1563-1572
Flight initiation distance (FID), the distance at which an organism begins to flee an approaching threat, is an important
component of antipredator behavior and a potential indicator of an animal’s perception of threat. In a field study on parrotfishes,
we tested the predictions that FID in response to a diver will increase with body size, a correlate of reproductive value,
and with experience of threat from humans. We studied a broad size range in four species on fringing reefs inside and outside
the Barbados Marine Reserve. We used the Akaike's Information Criterion modified for small sample sizes (AICc) and model averaging
to select and assess alternative models. Body size, reserve protection, and distance to a refuge, but not species, had strong
support in explaining FID. FID increased with body size and generally remained two to ten times fish total length. FID was
greater outside the reserve, especially in larger fish. Although we were not able to completely rule out other effects of
size or reserve, this study supports predictions of an increase in FID with reproductive value and threat from humans. 相似文献
536.
黄春蕾 《中国人口.资源与环境》2004,14(5):99-102
近来我国城市公用事业的市场化改革正在快速发展,但污水处理作为城市公用事业的,市城化改革进展却十分缓慢,绝大部分城市的污水处理行业仍在传统的政府断经营的轨道上运行,本文从我国现实出发,认为政府职能未能及时调整是导致改革进展缓慢的重要原因,提出必须以市场为导向定位政府职能,充分发挥市场机制在污水处理中的作用,并通过重点培育和完善市场及市场机制,加快城市基础设施建设投资体制改革,加强污水处理监管体制建设等措施,推进污水处理市场化改革,这对我国政府导推进城市其它公用事业市场化改革无疑具有重要的借鉴意义。 相似文献
537.
BENJAMIN L. NICHOLSON ANASTASSIOS N. PERAKIS JONATHAN W. BULKLEY 《Environmental management》2003,31(4):0532-0545
Through discussion of causative factors and examination of historical data, petrochemical spill prevention in US waters is
reviewed. Unintentional petrochemical outflow is analyzed in a comprehensive manner and presented as a hierarchical sequence
of antecedent events to reveal the trends of causative factors leading to release. Specifically, a seaborne petrochemical
spill is examined in terms of four basic, antecedent events: (1) an underway source, (2) a failure incident, (3) a marine
accident capable of breaching the hull and cargo block, and (4) the onset of outflow. These events are further subdivided
into underlying, contributing events to form a causative framework for spill prevention. While a hierarchical review is not
necessary to uncover the elements of causation, it does provide a comprehensive and logical structure that clearly defines
these elements in terms of occurrence frequency and contribution to resulting outflow. It is found that relatively small,
frequent spills less than 40,000 liters (10,567 gallons), attributable to human operator failures, leading to grounding, and
cargo transfer system failure accidents, dominate US seaborne petrochemical outflow from 1992 to 1999. Given the frequency
of groundings, structural reinforcement regulations such as those contained in the Oil Pollution Act of 1990 (requiring double
hulls) appear well justified. However, passive restraint systems are secondary to the need for vigilant training and licensing
of tank vessel operators. 相似文献
538.
539.
油气田含盐水淡化和污水除盐现状及发展 总被引:2,自引:0,他引:2
依据资料调研和现场调查,从5个方面介绍了油气田含盐水的状况,包括油气田含盐水类型、特征、淡化及处理技术,国内外含盐水淡化技术研究现状及最新发展,我国油气田含盐水淡化研究的着眼点和宜采用的技术。强调在油气田范围内,开展含盐水淡化处理技术研究,从根本上解决水资源短缺和排水造成的损失已成为油气田开发建设中不可忽视的问题。 相似文献
540.