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721.
Malgorzata Kwiecień 《Environmental monitoring and assessment》1997,46(3):191-207
A new, direct method was developed for quantifying inorganic particulate aerosols trapped by the forest canopy, and for determining the resulting input of elements to a forest ecosystem. The method is based on direct measurements of only six parameters. Using this method, it is possible to determine the load of aerosols trapped by the forest canopy and deposited to leaves, as well as the load of aerosols falling to the forest floor by impaction on plants. It is also possible to estimate the aerosol input of soluble and insoluble elements to an ecosystem. With this new method it has been found that the load of aerosols trapped by the canopy of a mixed forest located in the Rybnik Coal Basin averaged 189.0 kg x ha-1 x growing season-1, or 39.3% of the total inorganic particles reaching the ecosystem. The trapped aerosols provided 13.4 kg x ha-1 of soluble nitrogen and 0.91 kg x ha-1 of insoluble nitrogen over the growing season. At the same time, the input of soluble nitrogen from the atmosphere with rainfall to an open area averaged 13.9 kg x ha-1, and the input of insoluble nitrogen with inorganic dusts averaged 1.4 kg x ha-1. 相似文献
722.
This study examined possible routes for lead (Pb) accumulation in resident pigeons collected from rural, urban, and four industrial sites in Korea. The accumulation pattern of Pb was comparable to the study sites. The highest Pb concentration was found in the bone, followed by kidney, liver, and lung of pigeons. Highest Pb residues in bones were found in urban (Seoul), and two industrial complex areas (Busan and Ulsan), which were about 15 times higher than rural area (Duckjuk island), and followed by Ansan and Yochon industrial areas. Regional Pb variations in liver, kidney, and lung tissues were also similar pattern with the bone Pb difference. These findings indicate that Pb accumulation in tissues of pigeons may be affected by the Pb exposure in their respective habitats. Crop contents and gizzard materials were investigated as representing the ingested items. No difference of Pb concentration was observed in major foods (maize and/or wheat) of crop contents in the study sites except Busan, whereas variations of Pb levels in gizzard materials were indicative of a similar pattern with tissue Pb differences. The Pb concentration in tissues of pigeons did not correspond well to the atmospheric Pb levels. With regard to possible Pb sources, ingested items especially materials present in the gizzard are important sources for Pb contamination to pigeons because Pb-containing sources may be expected to present in roadside particles, dusts, paint chips and building flakes. However, air Pb value being low may not affect significant as the regional variations in tissues of pigeons. 相似文献
723.
通过对重量法,容量法,比色法与仪器法的机理特点分析理顺环境监测分析的本质关系,以便更好地研究,开发和使用各种监测分析方法。 相似文献
724.
通过对中国石化仪征化纤股份有限公司(以下简称仪化公司)排放废水中乙醛污染的调查,表明仪化公司排放的含乙醛废水主要产生于聚酯生产过程中的工艺废水,喷淋废水,冲洗地面和其他跑、冒、滴、漏的废水(“清下水”)。1996年-2000年污水处理场日排放含乙醛废水约5.66万t,日排放含乙醛的“清下水”约3万t。排放的乙醛在长江仪征段未检出,在沿山河和胥浦河水中有不同程度的检出和超标,超标率分别为50%和9.1%,最大超标倍数分别为8.88倍和0.14倍。对长江仪征段乙醛污染的影响预测结果为:污水处理场在非正常处理情况下(即直排),其排放的废水将在排污口周围形成长1250m,宽200m的污染带,污染面积为25万m^2。 相似文献
725.
化学气相沉积法可对13X分子筛进行孔径修饰,并用于含重金属离子废水的净化处理。研究结果表明,随13X分子筛外表面SiO2沉积量的增加,孔径收缩。 相似文献
726.
化学需氧量(COD)测定法的现状及最新进展 总被引:23,自引:0,他引:23
化学需氧量(COD)是水质监测的一个重要参数,本文对化学需氧量的测定现状和最新进展作了简要评述。 相似文献
727.
Worldwide, paper production is a major industry that contributes about 3 percent of Gross World Product. The paper cycle involves a broad range of natural resource and environmental impacts because fiber supply relies on trees, paper manufacturing requires fuel inputs, and paper waste disposal can contribute to emissions of the potent greenhouse gas (GHG), methane (CH4). In some countries, the paper cycle may be seen as a net sink for GHG because of reliance on renewable wood by-products and the maintenance of forest plantations. On a worldwide basis, however, this study demonstrates that the paper cycle is a significant contributor to GHG emissions, adding emissions at least comparable in magnitude to that of Australia each year. The estimated global warming contribution of paper in landfills is estimated to be similar to that of paper manufacturing processes, on a heating-equivalent basis. In some temperate regions, original old-growth forests are still harvested to supply pulpwood, resulting in a significant loss of carbon (C) storage. In theory, the paper cycle holds the promise of achieving zero net emissions if pulpwood production, consumption and disposal are carefully managed. In practice, even stabilization of emissions at current levels would be challenging and entail changes comparable to a 20 percent reduction in CH4 generation from landfilled paper, and a 2.5 percent annual increase in plantation establishment would be needed to offset the projected increase in emissions from paper manufacturing. 相似文献
728.
729.
本文根据历年统计资料对安徽省固体废物管理现状进行了分析,认为该省固体废物管理具有如下特点:(1)工业固体废物产生量总体上存在着上升趋势,并将随着经济发展继续增加;(2)固废综合利用率逐步提高;(3)虽然近年来工业固体废物排放量大幅下降,但污染隐患依然存在。本文还探讨了当前该省工业固废管理存在的问题,提出了加强工业固废管理的对策建议。 相似文献
730.
间歇式活性污泥法处理啤酒废水 总被引:5,自引:1,他引:5
在实验研究基础上,成功地应用间歇式活性污泥法(以下简称SBR法)处理啤酒生产废水。实践证明该工艺具有总投资省、处理效果好,对废水水质适应性强、工艺稳定、能耗低等优点。 相似文献