| The persistent organic pollutants (POPs) and Be absorbed by soil and air have been collected and analyzed from several typical areas in East Asian monsoon region in our country, for three years and covering the east and the south of China. The status of pollution and the character of distribution to POPs have been studied systematically. An investigation has been launched for the distribution character of’Be, while a try has been put out innovatively to research the role’Be played in POPs removing tracing.Combining many literatures, the research results showed:OCPs in the surface soil had not a regular latitude scatter law, and it is the dosage used in the past and the using status of Lindane, Dicofol and etc that are the key factors influencing OCPs residual in soils now. There were the higher concentration sites of the 7 PCBs in Dongbei area. Studying the typical agriculture areas in Yangtze River delta and Pearl River delta for soil-air diffusion of OCPs by the fugacity model simply, we found out that the fugacity in soil was higher than in air for OCPs mostly, namely, the OCPs in soils were the source for those in air.The results from air samples showed that the OCPs and PCBs in vapor and aerosols all had distribution rules along latitude. In the five cities in the northern China, Beijing, Qingdao, Shenyang, Meihekou, Jilin, DDTs were the main compounds for total OCP in vapor. Total OCP and total PCB would have the lower concentration with the latitude increasing. Using the Clausius Clapeyron equation, we concluded that the temperature was important for DDTs and PCBs transporting from mid-low latitude to high latitude, but it was not for HCHs. In the different cities along the latitude, Guangzhou, Suzhou, Qingdao, Beijing, Heihe, all the POPs absorbed in aerosols showed us a latitude distribution model of two peaks. The lowest value appeared in Qingdao, what was maybe caused by oceanic climate.Analyzing POPs and 7Be in the aerosols samples from Beijing and Guangzhou, we drew many conclusions. In Beijing TSP samples, the concentrations of HCHs, DDTs and PCBs seemed to follow the same pattern of increasing or reducing, but the trend with time was uniform. DDTs and PCBs had a better correlation than what they were to HCHs. In the TSP samples from Guanzhou city, HCHs and DDTs had the similar change patterns that they would increase or decrease at the same time, and PCBs and PBDEs also have the trends. But between the two groups there were opposite phenomena that one increased while the other one was decreasing. The POPs concentrations in TSP would be affected by many meteorological conditions directly, such as precipitation, the influence of wind. But the natural temperature had no significant correlation to POPs.The 7Be concentrations in Beijing TSP samples ranged from 4.90 mBq/m3 to 15.64 mBq/m3, averaging 8.64 mBq/m3, which is higher than the yearly mean value all over the world (3.5 mBq/m3),. The lowest value appeared in February and the highest value appeared in November. The’Be concentrations in Guangzhou TSP samples ranged from 0.07 mBq/m3 to 8.45 mBq/m3, averaging 2.59 mBq/m3, which is lower than the world yearly mean value. The highest value appeared in May and the lowest value appeared in August. The influence factors to 7Be concentrations in near-surface atmospheric were mainly latitude, air-transportation and aerosols deposition. Determining 7Be, we found out the "spring leak" existing. Data showed, in different seasons and different latitude area, there were some similar and some different trends between 7Be and POPs. The similarity was that rainfall was the most important factor affecting 7Be and POPs in air in summer and autumn. The differences between’Be and the organic compounds were that the sources of them were various. In the areas where’Be had no significant change, we could use the ratio ΣOPs/7Be to reveal the change of the POPs source.In our studied areas, Be had shown us a Gaussian distribution, and the curve would move with the season changing in a certain latitude range. |
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