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2013年春夏季莱州湾海水环境要素特征和富营养化评估 总被引:1,自引:0,他引:1
根据2013年5(春季)、8月(夏季)莱州湾海水环境要素的调查资料,采用富营养化指数、潜在性富营养化评价模式和灰色聚类分析方法研究环境要素特征和评估海水富营养化状况。结果表明,无机氮是莱州湾水质的主要污染要素,春夏季的N/P平均值分别为100.76、117.84,潜在性富营养化评价模式结果表明,春夏季各站位的营养级均只包括ⅣP、ⅥP两类,磷限制为莱州湾的营养盐结构特征;富营养化指数评价结果表明,春季和夏季E>1站位比例分别为65%、20%;灰色聚类分析结果表明,春季Ⅱ级、Ⅲ级的站位比例分别为95%、5%,夏季Ⅱ、Ⅲ级的站位比例分别为70%、25%,Ⅱ级中的部分站位具有较大潜在富营养化风险。 相似文献
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针对南京市典型道路的交通噪声控制措施,分别选取低噪声路面、声屏障、隔声窗3种噪声控制措施进行监测,监测显示低噪声路面对整体声级降噪有限,声屏障对于1kHz倍频带以上的中高频隔声相对较好,真空玻璃隔声窗能对低频噪声有显著改善。 相似文献
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Thousands of hard rock mines exist in the western USA and in other parts of the world as a result of historic and current gold, silver, lead, and mercury mining. Many of these sites in the USA are on public lands. Typical mine waste associated with these sites are tailings and waste rock dumps that may be used by wildlife and open-range livestock. This report provides wildlife screening criteria levels for metals in soil and mine waste to evaluate risk and to determine the need for site-specific risk assessment, remediation, or a change in management practices. The screening levels are calculated from toxicity reference values based on maximum tolerable levels of metals in feed, on soil and plant ingestion rates, and on soil to plant uptake factors for a variety of receptors. The metals chosen for this report are common toxic metals found at mining sites: arsenic, cadmium, copper, lead, mercury, and zinc. The resulting soil screening values are well above those developed by the US Environmental Protection Agency. The difference in values was mainly a result of using toxicity reference values that were more specific to the receptors addressed rather than the most sensitive receptor. 相似文献
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Honey U. K. Pillai K. V. Jayalakshmy A. Biju K. J. Jayalakshmi V. T. Paulinose C. B. L. Devi V. R. Nair C. Revichandran N. R. Menon C. T. Achuthankutty S. U. Panampunnayil 《Environmental monitoring and assessment》2014,186(6):3305-3319
The study was carried out to understand the variability in phytoplankton production (Chlorophyll a) and mesozooplankton diversity from two different shallow coastal regions of south Andaman viz. Port Blair Bay (PBB), the only real urban area among the islands and Mahatma Gandhi Marine National Park, a Marine Protected Area (MPA) at Wandoor. Seasonal sampling was carried out during the Northeast monsoon (NEM—November 2005), Intermonsoon (IM—April 2006), and Southwest monsoon (SWM—August 2006). Significant (P?<?0.05) seasonal variation was observed in the environmental variables at both the regions. Higher average chlorophyll a (Chl. a) and mesozooplankton standing stock were observed at PBB compared to MPA, but the seasonal variation observed was marginal at both the study areas. Chl. a showed a steep increasing gradient from outer to the inner regions of the PBB. The number of zooplankton taxa recorded at both areas was quite similar, but marked differences were noticed in their relative contribution to the total abundance. Eventhough the Copepoda dominated at both the areas, the non-copepod taxa differed significantly between the regions. Dominance of carnivores such as siphonophores and chaetognaths were noticed at PBB, while filter feeders such as appendicularians and decapod larvae were more abundant at MPA. A total of 20 and 21 copepod families was recorded from PBB and MPA, respectively. Eleven species of chaetognaths were observed as common at both areas. Larval decapods were found to be predominant at MPA with 20 families; whereas, at PBB, only 12 families were recorded. In the light of the recent reports on various changes occurring in the coastal waters of the Andaman Islands, it is suspected that the difference in Chl. a as well as the mesozooplankton standing stock and community structure observed between the two study areas may be related to the various anthropogenic events influencing the coastal waters. 相似文献
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M. Ausejo M. Recuero C. Asensio I. Pavón J. M. López 《Environmental Modeling and Assessment》2010,15(2):125-135
This article aims to discuss the influence of input data on the simulation model when designing Strategic Noise Maps. The
studied noise map was made in the Macrocenter of the Independent City of Buenos Aires (Argentina), which has an approximated
extension of 20 km2 and about 500,000 inhabitants. The several input data for the model are analyzed, for their quality and the lack of some
of them could affect the final result. Also, the evolution and validity of experimental measurements are analyzed when validating
a simulated map. Finally, a study of the uncertainty of the map based on the input data is made, comparing it with the recommendations
internationally adopted. 相似文献