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Effects of traffic pollution on the genetic structure of Poa annua ***

Journal of Environmental Sciences 2004年第3期16卷 454-457页

作者： LINing CHENXiao-yong SHENLang LIYuan-yuan CAIYue-wei DepartmentofEnvironmentalSciences EastChinaNormalUniversityShanghai200062China KeyLaboratoryofGeographicInformationScience TheMinistryofEducationShanghai200062.China

The genetic composition of Poa annua L. populations with a series of traffic pollution was studied by starch electrophoresis. Five enzyme systems were stained. The results showed that: (1) traffic pollution can dramatically change genotypic frequencies at some loci of P. annua populations. Significant deviations from Hardy Weinberg equilibrium were observed on loci Fe 1 and Me due to the excess of heterozygotes in some populations. (2) The effective number of alleles per locus and the observed and expected heterozygosity were higher in the pollution series than in the clear control site(Botanic Park population), but the increase was not related with the pollution extent. (3) Most genetic variation was found within populations, and only 6 21% was among populations of the polluted series. Slightly higher differentiation( F ST =7 98%) was observed when the control population was included. (4) The calculated gene flow(Nm) is 2 8841 per generation. The mean of genetic identity is 0 9864 and the genetic distance average to 0 0138

关键词： genetic composition traffic pollution allozyme analysis Poa annua L.

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Mitigation of traffic pollution through Application of Venturi Effect ——Proposal of Mega-scaled Purification Towers for Beijing’s Interchanges

Mitigation of Traffic Pollution through Application of Ventu...

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作者： Dukic Milica 天津大学

学位级别：硕士

The principle problem addressed in the conducted research was the issue of excessive pollution being emitted from Beijing’s most congested interchanges which contributes to the overall poor air *** main aim was to examine which principles could be applied through architecture for assisting in the process of pollution *** first objective of this research included detecting and precisely mapping the biggest pollution contributors among Beijing’s interchanges,and thus defining spots in the city that are in need of urgent air ***,the research dealt with introducing Venturi scrubber as the possible pollution *** it already proved highly effective and successful in the process of treating pollution for the purposes of industry,this research aimed to prove that the same method could be applied for the abatement of traffic induced *** than this,since Venturi scrubbers usually operate on a much smaller scale that does not conform with architectural one,it was necessary to examine whether this principle could be used on a large scale with the same *** this reason,series of simulations have been conducted to see how the airflow performs in large structures atria observing criteria such as velocity and pressure *** on the simulations,an optimal model was adopted for the proposal of Venturi *** final objective of the research included the proposal for towers,which introduced how a megascaled Venturi scrubber can be implemented in the context of the *** previously marked interchanges were used as a platform where these towers could be installed,reestablishing concepts such as role of infrastructural buildings in the city context,providing land from traffic infrastructure,but most importantly,concept of integrating mechanical and architectural features of the building in one hybrid *** project for Venturi towers provides a proposal how a problem of traffic induced pollution can be treated

关键词： traffic pollution Venturi Effect Air purifier towers Beijing Interchanges

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Asphalt　fractions　in　airborne　particles　from　highway　traffic　and　the　accumulation　in　plants

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Journal of Environmental Sciences 1996年第2期8卷 196-202页

作者： He Kebin(Department of Environmental Engineering, Tsinghua University, Beijing 100084,China)Hans Mosbaek Jens Chr. Tjell(Department of Environmental Engineering,Technical University of Dentnark, 2800 Lyngby,Denmark) Dept. of Environmental Engineering Tsinghua University Beijing 100084 China Dept. of Environmental Engineering Technical University of Denmark 2800 Lyngby Denmark

With reference to ASTM D4124, asphalt fractions, including polar aromatics (polars),naphthene aromatics (aromatics) and saturates,were characterized both in airborne particles collected in the distances of 2.0 -83.6m from the highway and in the plant samples (including grass,leaves and wheat straw) collected in the distance of 2.0 -10. 0m from the highway. In comparison to the results of diesel particulate, background plant samples and asphalt cernent samples from highway surface, it is concluded that there could be asphalt rnatters in airborne particles and asphalt makes the rnain contributions to the accumulation of the three factions mentioned above in plant species. In the ambient air,the concentrations of the three asphalt fractions are 0. 54- 3.06 ×10-3 mg polars,1. 77- 9. 50 × 10-4 mg aromatics and 0. 21- 1. 23 × 10-4 mg saturates for per cubic meter air. The percentage of bitumen in airborne particles is 1. 61%-11. 02%. In the plant samples, the concentrations are 0. 29- 3.07mg polars, 0.89- 3.89 aromatics and 0. 37-1. 53 mg saturates for per gram dry plant materials.

关键词： asphalt airborne particle traffic pollution HPLC.

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