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31.
32.
S.M.Semenov 《环境科学学报(英文版)》1992,4(1):10-14
An integrated approach was developed to determine the critical levels of air pollution for ecological standard setting based on the unified index of biological response, by taking into account the effects of all pollution components simultaneously. An empirical model of plant productivity was taken as the dose response model for gaseous pollutant effect on the productivity of trees and the annual productivity of plants was used as the above mentioned index. The CO2 increase in the lower atmosphere was considered to potentially increase plant productivity and NO2 was estimated as neutral while being dangerous for plants as a chemical precursor of ozone or as a source of acidification. The maximum permissible chronic O3 and SO2 levels for trees were estimated and it was found that O3 is much more phytotoxic, as compared to SO2 , with a rather narrow range of permissible levels (27-33 ppb) which complicates its monitoring and control. 相似文献
33.
Xu Song-ling 《环境科学学报(英文版)》1999,(1):4
1IntroductionVilageandtownshipindustry(VTI)isbecomingaveryimportantcomponentofChinaseconomyandenvironment.In1992,VTIproduced... 相似文献
34.
磺酰脲类除草剂的残留分析 总被引:8,自引:0,他引:8
磺酰脲类除草剂是一类新型超高效除草剂,大约包括2V化合物,已被广泛用于禾谷作物防除阔叶杂草以及某些禾本科杂草,该类除草剂在环境中的残留浓度〈1μg.kg^-1水平。常规的分析方法包括生物鉴定,酶免疫分析,气相色谱法和高效液相色谱法(HPLC)、HPLC/MS联用后,可以准确测定复杂环境样中磺酰脲类除草剂的痕量残留。 相似文献
35.
The waterquality of the downstream of Nanfei River and the northwest area of Lake Chao is evaluated from organic analysis aspect. PAHs such as fluoranthene, pyrene are detected in the waters collected from downstream river and river mouth. More phenolic compounds are found in the river water. Some halogenated hydrocarbons are present in the river and lake waters. A great many of aliphatic hydrocarbons and benzene hydrocarbons found in all the water samples are about one third of the total organics detected. The hydrophobic components are found to be present not only in water but also in suspended sediment. The ratio of the amount existing is 0.4 in sediment and 1 in particle-free water. The quantity of humic materials existing in lake water is larger than that in river water. The proportion of the humic materials in lake water to that in river water is 1.9 to 1. In the lake water, some natural substances, such as dimethyl disulfide, alpha-pinene, azulene, and 6- methyl -2-heptanone are observed. 相似文献
36.
A study for the photochemical behavior of some polyaromatic hydrocarbons (PAH), for example B(a )P, B( k )F and fluoranthene in coal smoke particles was performed by using indoor Teflon smog chamber.Experiments suggest that the photochemical reaction of PAH is first order reaction and kinetic rates of some PAH were obtained. It was shown that the reaction rate constant is proportional to light intensity and water vapor concentration. Temperature and PAH loading also have influence on PAH decay rate. A model for PAH loss has been set up on the basis of the results of our experiments and the simulating results of this model suggest that coal particle PAH half lives are of the order of a period of days in winter and a few hours in summer. Other factors which may have effect on the photochemical reaction of PAH have also been discussed. 相似文献
37.
This paper, based on the autonomy concept, continues to investigate hierarchical forms and spatial structure of ecosystems. The former can lead to limits for the selection of the component parts of an ecosystem and a distinction between its endogenous and exogenous variables; and the latter can be lead to a hypothesis of the space of an ecosystem: the space of an ecosystem = its habitat area + supporting area + impact area, and two characteristics of ecosystems, space-overlapping and the area of ecosystem space, have been further studied referring to human activities. 相似文献
38.
加强地市级环境自动监测监控中心建设的思考 总被引:5,自引:0,他引:5
以建设福州市环境监测监控中心为例,讨论了在地市级环境自动监测监控中心建设过程中应坚持的指导思想,在进行系统设计中应考虑的功能需求,以及应注意的技术方面的问题。 相似文献
39.
AsayofsomevolatilecompoundsinhumanexhalationQinTao,XuXiaobaiResearchCenterforEcoEnvironmentalSciences,ChineseAcademyofScie... 相似文献
40.
Progress in the research on aquatic environmental nonpoint source pollution in China 总被引:1,自引:0,他引:1
ProgresintheresearchonaquaticenvironmentalnonpointsourcepolutioninChinaBaoQuansheng,MaoXianqiang,WangHuadongInstituteofEnviro... 相似文献