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Passive diffusion sampling of sulfur dioxide in India: Impact assessment on arid areas

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Science China Earth Sciences 2002年第Z1期45卷 137-141页

作者： S. Kumal M. Mohan R. Datta L. N. Mithila University A-9 L.I.G. Ashiana Nagar Patna Bihar 800025 India Center for Atmospheric Sciences. I.I.T. Delhi Hauzkhas N. Delhi-110016 India 1453 Fifield Hall Department of Plant Pathology University of Florida Gainesville Florida USA

Environmental constraints have drastically limited options of sustainable developmentand have severely offset many developmental schemes. In this paper, possibilities of acidic depo-sition, as a counter measure of desertification, are analyzed. Seasonal data of ambient sulfur di-oxide, pH of rain water and soil acidity are collected for over an year and analyzed. Arid environ-ment of surrounding areas of Delhi is considered and analyzed. Though ambient sulfur depositionis well below critical level, it might not be truly indicative of plant survival in arid areas. Results maybe useful in arid area afforestation, and polluting industries relocation, which holds tremendouspotential vis-a-vis sustainable development.

关键词： sulfur dioxide, diffusion, India.

Influencing domain of peripheral sources in the urban heavy pollution process of Beijing

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Science China Earth Sciences 2005年第4期48卷 565-575页

作者： KANG Shichang Paul A. Mayewski Climate Change Institute University of Maine Orono ME 04469 USA

The effect of city’s peripheral pollution sources is one of the key issues urgent to be solved in the decision-making of Beijing’s environmental pollution control. This paper comprehensively analyses the surface observations, and the satellite remote sensing data of Moderate Resolution Imaging Spectroradiometer (MODIS) and Total Ozone Mapping Spectrometer (TOMS) during the Beijing City Atmospheric Pollution Experiment (BECAPEX) from January to March, 2001, presents an "upstream" wind field resultant vector method for tracing peripheral pollution sources, and finds that the features of the urban heavy pollution processes of Beijing are significantly correlated with the impact of the emission sources of southern peripheral cities, and the pollutants transferred northwards from distant upstream sources are retarded by the U-shaped "Valley" topography in Beijing’s periphery. The two factors are responsible for the formation of the S-N zonal influencing domain of pollutants from the southern peripheral areas to Beijing. The paper also comprehensively analyses the features of flow field in the heavy pollution process in the Beijing region, and compares the heavy pollution process with samples of good air-quality days from January to March, 2001. The experiment of Hybrid Single-Particle Lagrangian Integrated Trajectory model (HYSPLIT-4) further reveals the diffusion trajectory of pollutants of the cities in Hebei and Shandong provinces and Tianjin city in the heavy pollution process of Beijing, and the simulations of the Regional Atmosphere Model System (RAMS) confirm the possible contribution of peripheral sources to the exceptionally heavy pollution process of the urban area of Beijing, thus revealing that the input of pollutants from southern peripheral cities is one of the important factors responsible for aggravating urban heavy pollution processes.

关键词： city's periphery, distant transfer, pollutants transfer, dynamic diffusion, influencing source.

Analysis of Interannual Variations of Inorganic Nitrogen in the Bohai Sea

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Marine Science Bulletin 2002年第2期4卷 15-24页

作者：石强高振会杨建强 North Sea Monitoring Center SOA Qingdao 266003

According to the Bohai Sea cross-section data during 1985～1998, the high concentration inorganic nitrogen in the Bohai Sea section bottom layer water nearshore diffused and transferred to the middle of the Bohai Sea year after year. The interannual variations of the concentration of inorganic nitrogen in the Bohai Sea section bottom layer water may reflect the degree of eutrophication more steadily. The nitrate nitrogen and nitrite nitrogen are used to show quasi-equilibrium state interannual variations, but with the aggravation of seawater pollution, the quasi-equilibrium state of interannual variations has been broken and the marine biological-chemical processes can only maintain the secondary part of the interannual variations in a quasi-equilibrium state, but are not sufficient to prevent the main pan of interannual variations from deviating from the quasi-equilibrium state. The spatial distributions of inorganic nitrogen would be affected by the reproduction and swarming of marine life.

关键词： Inorganic nitrogen, transference, diffusion, quasi-equilibrium state