Preface

Anthropogenic emissions impact significantly the atmospheric environment which human being relies on, e.g., global warming, stratospheric ozone depletion, photochemical smog, acid rain, haze and so on. Although clean air actions have been legislated by many nations to mitigate pollutants＇ emission with the aim of protecting the atmospheric environment, serious air pollution events are frequently observed in different regions, especially in developing countries. To best evaluate the effect of various control measures as well as the influence of various pollutants on the atmospheric environment, the levels, sources and sinks of the pollutants are needed to be comprehensively investigated. Since atmospheric environment involves multidisciplinary approach, scientists with different disciplines together can provide profound understandings about the atmospheric environmental problems. Sino-French Workshop on Atmospheric Environment is just one of such platforms to join scientists together for collaboration, exchange of experience and ideas.     

Contamination of soil, leaves and vegetables by polychlorinated biphenyls in Xiamen region, China

The paper aimed to identify the primary of polychlorinated biphenyls(PCBs) in the Jiulong River Estuary, investigate the spatial distribution of PCBs contamination in the environment, localize the atmospheric source and evaluate ongoing PCBs emissions by analyzing soil samples collected along the Jiulong River region. In addition, the accumulation of PCBs in the human food chain was quantified by analyzing leaf of orange trees and vegetable samples collected along a gradient of soil/atmospheric contamination moving away from the source. Consequently, the impact on the human health and the ecosystem was quantified, different management options were proposedto reduce this impact and to carry out research on organic contaminants along the Jiulong River and Xiamen region.     

On the influence of sand-wind on atmospheric environment

The authors seek, through tests on simulated sand samples in a wind tunnel and analysis of minerals combination and trace elements, to discover the environmental implications of flying-up, falling-down and concentration variation as a function of natural wind speed and direction, distance of movement, range and extent of influence on the atmospheric environment, of micro-granular components on the ground surface in the Keerqin desert area in northwest Liaoning Province of China.     

Effect of temperature tuning on the aerosol acoustic aggregation process

Diesel exhaust aerosols(DEAs) can absorb and accumulate toxic metal particulates and bacteria suspended in the atmospheric environment, which impact human health and the environment.The use of acoustic standing waves(ASWs) to aggregate DEA is currently considered to be an efficient particle removal method; however, study of the effect of different temperatures on the acoustic aggregation process is scarce. To explore the method and technology to regulate and optimize the aerosol aggregation process through temperature tuning, an acoustic apparatus integrated with a temperature regulation function was constructed. Using this apparatus, the effect of different characteristic temperatures(CTs) on the aerosol aggregation process was investigated experimentally in the ASW environment. Under constant conditions of acoustic frequency 1.286 kHz, voltage amplitude 17 V and input electric power 16.7 W, the study concentrated on temperature effects on the aggregation process in the CT range of 58–72°C. The DEA opacity was used. The results demonstrate that the aggregation process is quite sensitive to the CT, and that the optimal DEA aggregation can be achieved at 66°C. The aggregated particles of 68.17 μm are composed of small nanoparticles of 13.34–62.15 nm. At CTs higher and lower than 66°C, the apparatus in non-resonance mode reduces the DEA aggregation level. For other instruments, the method for obtaining the optimum temperature for acoustic agglomeration is universal. This preliminary demonstration shows that the use of acoustic technology to regulate the aerosol aggregation process through tuning the operating temperature is feasible and convenient.     

Influence of acid deposition on atmospheric corrosion of zinc

Site exposure tests both open and sheltered have been carried out in acid deposition area in Southwest China. Results from six sites show that acid deposition exerts a great influence on atmospheric corrosion of Zn, and it is more serious in wet condition. Basically, Zn corrosion is directly proportional to time of exposure. While SO2 is the main pollutant of the atmosphere environment, Zn corrosion has a linear relationship to SO2 depositing rate and a hyperbolic to rain pH value.Observations by SEM, EDAX and X-ray diffraction show that under sheltered exposure condition, the corrosion products of Zn in heavy acid deposition area principally are sulphates.Based on the corrosion rates measured, the working life of galvanized steel can be predicated.     

The Second Sino-FrenchWorkshop on Atmospheric Environment (Orleans, December 2010): Preface

A sound scientific understanding of the factors affecting the environment is essential to guarantee the sustainable development of the world's economic and societal activities.Many environmental issues,such as air quality and climate change are intimately linked to atmospheric chemistry and physics,therefore research in these areas is of tremendous importance.Both anthropogenic and biogenic emissions contribute greatly to the chemical composition of the atmosphere.Even though the atmosphere is a self-cleaning system through its photochemically-driven reactions,the hazardous direct impacts of primary and secondary pollutants on human health and ecosystems are observable and have been evidenced on different scales from local to global (e.g.ozone hole,climate change,air quality…).The chemical processing of the species present in the atmosphere is one of the most important players in driving the evolution of the atmosphere.     

Residential environmental evaluation of local cities considering regional characteristic and personal residential preference-a case study of Saga City, Japan

Questionnaire surveys and subjective evaluations on residential environment were performed in order to grasp the main factors of residential environment of small local cities. The suitable evaluation index system was established, and the regional residential environment characteristics and personal residential preference types were analyzed, so that their influence on residential environment evaluation could be grasped. The results can be applied to the residential environment planning, construction and monitoring of local cities.     

Influence of the Haizhou Open Pit Coal Mine on the atmospheric flow over Fuxin, China

The influence of the Haizhou Open Pit Mine on the atmospheric flow in nearby Fuxin City in China was analyzed with the aid of the steady-state Navier-Stokes equations. The finite element method was used to obtain numerical solutions to these equations. The results showed that the Haizhou Open Pit Coal Mine contributes to the turbulent flow in the Fuxin City and its surroundings. However,when compared with the climatic effects, the open pit mine has a relatively small impact on the atmospheric flow over Fuxin.     

Antimony speciation in the environment: Recent advances in understanding the biogeochemical processes and ecological effects

Antimony(Sb) is a toxic metalloid, and its pollution has become a global environmental problem as a result of its extensive use and corresponding Sb-mining activities. The toxicity and mobility of Sb strongly depend on its chemical speciation. In this review, we summarize the current knowledge on the biogeochemical processes(including emission, distribution,speciation, redox, metabolism and toxicity) that trigger the mobilization and transformation of Sb from pollution sources to the surrounding environment. Natural phenomena such as weathering, biological activity and volcanic activity, together with anthropogenic inputs, are responsible for the emission of Sb into the environment. Sb emitted in the environment can adsorb and undergo redox reactions on organic or inorganic environmental media, thus changing its existing form and exerting toxic effects on the ecosystem. This review is based on a careful and systematic collection of the latest papers during 2010–2017 and our research results, and it illustrates the fate and ecological effects of Sb in the environment.     

Effect of free-air CO2 enrichment on nematode communities in a Chinese farmland ecosystem

At a rice-wheat rotational free-air CO2 enrichment(FACE) platform, the effect of elevated atmospheric CO2 on soil nematode communities in a farmland ecosystem was studied. Wheat plots were exposed to elevated atmospheric CO2 (ambient 370 μl/L 200 μl/L).32 families and 40 genera of nematode were observed in soil suspensions during the study period. Under FACE treatment, the numbers of total nematodes, bacterivores and fungivores exhibited an increasing trend. Because of the seasonal variation of soil temperature and moisture, the effect of elevated atmospheric CO2 on soil nematodes was only observed under favorable conditions. The response of nematode communities to elevated atmospheric CO2 may indicate the change of soil food web.