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91.
Hijano CF Domínguez MD Gimínez RG Sínchez PH García IS 《Environmental monitoring and assessment》2005,111(1-3):75-88
The evaluation of certain vascular plants that grow in the city of Madrid as biomonitors of SO2 air pollution in urban environments has been carried out. Total concentration of sulphur in leaves of the chosen higher plants
as well as other parameters in close relation to this contaminant (visible injury symptoms, chlorophyll a- and b-content and
peroxidase activity) have been determined in order to study the spatial distribution and temporal changes in SO2 deposition. Results obtained show that coniferous species such as Pinus pinea, were more sensitive to SO2 atmospheric concentration than leafy species as Quercux ilex subspecies ballota and, in the same way, bush species, such asPyracantha coccinea and Nerium oleander, were more sensitive than wooded species, such as Cedrus deodaraandPinus pinea, respectively. There is a higher accumulation of sulphur in vegetable species located near highways and dense traffic incidence
roads and near areas with high density of population. The minimum values for accumulation of SO2 were registered in winter and spring seasons (from January to April) due to the vegetative stop; while maximum values are
obtained during the summer season (from June to September), due to the stoma opening. The highest increments in sulphur concentration,
calculated as the difference between two consecutive months, are obtained in May and June for all considered species except
forCedrus deodara and Pyracantha coccinea, both species have few seasonal changes during the whole year. Some species are more sensitive to natural washing than others,
showing a decrease in sulphur concentration after rainfall periods. 相似文献
92.
93.
亚铵法制浆造纸厂中段废水处理技术分析研究 总被引:1,自引:0,他引:1
通过对采用两级气浮做预处理 ,生物硫化床串联接触氧化做深度处理的治理技术的分析研究 ,结合废水处理工程实例 ,说明了用两级串联气浮 +硫化床 +接触氧化工艺处理造纸中段水技术切实可靠 ,该治理工艺对处理亚铵法麦草制浆造纸中段废水有较强的针对性和可行性。 相似文献
94.
95.
Wong MY Sauser KR Chung KT Wong TY Liu JK 《Environmental monitoring and assessment》2001,67(3):361-378
The green alga Selenastrum capricornutum expresses a uniqueascorbate peroxidase, that responds to copper and lead. Attemptswere made to test if this peroxidase could be used to monitor thelevels of copper and lead in natural waters. When S.capricornutum was exposed to a stormwater sample, the specificactivity of the peroxidase in the cell extract was commensuratewith the combined copper and lead contents in the sample. Theperoxidase responses were also correlated with the 96 hr biomasstoxicity assay of S. capricornutum. However, unlike thebiomass toxicity assay, the peroxidase activity was not affectedby the anions in the samples. The use of this peroxidase can beused as a marker for testing heavy metal toxicity in the water. 相似文献
96.
省级环境监测站在建设项目竣工验收监测中的地位和作用 总被引:4,自引:0,他引:4
建设项目竣工验收监测是环境监测工作的一项重要工作,也是"一控双达标"工作的重要一环.从锻炼队伍、保护队伍、巩固队伍、稳定队伍和纯洁队伍等方面综合分析,省级监测站在此项工作中应承担相应的责任,才能更好地发挥技术中心、信息中心、网络中心和培训中心的作用. 相似文献
97.
《中国环境监测》于2006年8月第22卷第4期发表了一篇名为“碱性高锰酸钾指数标准分析方法的错误”的文章,该文作者通过配制不同浓度的葡萄糖标准溶液,分别用酸性法与碱性法来测定其高锰酸盐指数值,对相应的结果与计算公式进行讨论,指出碱性高锰酸钾操作方法与计算公式均存在错误,并提出了碱性高锰酸钾测定的修正方法与公式。文章对上述观点和结论有不同的看法,从碱性高锰酸钾指数标准分析方法的试验操作步骤及方法原理的理解入手,进行相关的阐述和讨论。 相似文献
98.
Kimpo metropolitan landfill has received various kinds of wastessince January 1992. The leachate level was measured to be 10.3 m in May 1995 and the level increased to 12.2 m in August 1996. Therefore, to prove the reason for the increasing leachate level, we calibrated hydraulic conductivity of each waste andintermediate layer using the HELP (Hydrologic Evaluation ofLandfill Performance) model. The leachate generation data measured from February 1993 to October 1995 was used in the model calibration. As a result of a model calibration, we obtained anaverage infiltration ratio and used this in analysis of the total water balance to predict elevation of leachate level. Main causes of the elevation of the leachate level were the high water content of the waste and the degradation of the leachate-drainage system caused by the subsidence of a naturalbarrier layer. 相似文献
99.
100.
Gustavo Ratto Fabián Videla J. Reyna Almandos Ricardo Maronna Daniel Schinca 《Environmental monitoring and assessment》2006,121(1-3):325-340
This article presents and discusses SO2 (ppbv) concentration measurements combined with meteorological data (mainly wind speed and direction) for a five-year campaign (1996 to 2000), in a site near an oil refinery plant close to the city of La Plata and surroundings (aprox. 740.000 inh.), considered one of the six most affected cities by air pollution in the country. Since there is no monitoring network in the area, the obtained results should be considered as medium term accumulated data that enables to determine trends by analyzing together gas concentrations and meteorological parameters. Preliminary characterization of the behaviour of the predominant winds of the region in relation with potential atmospheric gas pollutants from seasonal wind roses is possible to carry out from the data. These results are complemented with monthly averaged SO2 measurements. In particular, for year 2000, pollutant roses were determined which enable predictions about contamination emission sources. As a general result we can state that there is a clear increase in annual SO2 concentration and that the selected site should be considered as a key site for future survey monitoring network deployment. Annual SO2 average concentration and prevailing seasonal winds determined in this work, together with the potential health impact of SO2 reveals the need for a comprehensive and systematic study involving particulate matter an other basic pollutant gases. 相似文献