四川省水体富营养状况时空分布调查

采用综合营养指数法对四川省主要河流营养状况进行调查评价,分析其时空分布规律。结果表明,2009年四川省水体综合营养状态整体处于中营养水平。从空间分布情况看,水体营养状态从优到劣依次为金沙江、长江干流、岷江、嘉陵江、沱江,其中沱江处于轻度富营养状态。从时间分布情况看,除沱江流域月度间变化较小外,其他调查河流水体营养状态月度间变化呈双峰型"M"状,营养指数主峰发生在8月;长江干流、岷江和嘉陵江次峰发生在4—5月,金沙江次峰发生在10月。     

Sources and seasonal variation of PAHs in the sediments of drinking water reservoirs in Hong Kong and the Dongjiang River (China)

The main objective of this study was to investigate occurrence of polycyclic aromatic hydrocarbons (PAHs) in the sources of the drinking water supply of Hong Kong. The main emphasis was on the Dongjiang River in mainland China which is the major source, supplying 80% of the total consumption in Hong Kong (the remaining 20% is obtained from rain water). Sediments were collected from four sites along the Dongjiang River and four reservoirs in Hong Kong during both the dry and wet weather seasons. The concentrations of total PAHs in the sediments ranged between 36 and 539 microg/kg dry wt. The lower levels were detected at the upstream site on the Dongjiang River and at the reservoirs in Hong Kong (44-85 microg/kg dry wt), while the mid- and downstream sites on the Dongjiang River were more polluted (588-658 microg/kg dry wt). Examination of the PAH profiles revealed that the mid- and downstream sections of the Dongjiang River contained high percentages of 4,5,6-ring PAHs, similar to the amounts of atmospheric particulate matter and road dust collected during the dry weather season from the Pearl River Delta region as reported in the literature. Seasonal changes were revealed in the reservoirs of Hong Kong, with higher PAH levels in the wet weather season than in the dry weather season. For those reservoirs in Hong Kong that store water from the Dongjiang River, a distinct seasonal pattern was also observed, namely, that under dry weather season conditions the PAHs found in the sediments were primarily from petrogenic source, while under wet weather season conditions they were from pyrolytic sources. No such pattern was detected in the reservoirs which stored only rain water.     

Distribution and source analysis of aluminum in rivers near Xi’an City, China

To study the status and source of aluminum (Al) contamination, a total of 21 sampling sites along six rivers near Xi’an City (Shaanxi province, China) were investigated during 2008–2010. The results indicated that the average concentration of total Al (Al_t) in the six rivers increased by 1.6 times from 2008 to 2010. The spatial distribution of Al_t concentrations in the rivers near Xi’an City was significantly different, ranged from 367 μg/L (Bahe River) to 1,978 μg/L (Taiping River). The Al_t concentration was highest near an industrial area for pulp and paper-making (2,773 μg/L), where the Al level greatly exceeded the water quality criteria of both the USA (Criterion Continuous Concentration, 87 μg/L) and Canada (100 μg/L). The average concentration of inorganic monometric aluminum (Al_im) was 72 μg/L which would pose threats to fishes and other aquatic lives in the rivers. The concentrations of exchangeable Al (Al_ex) in the sediment of the Taiping River sampled were relatively high, making it to be an alternative explanation of increasing Al concentrations in the rivers near Xi’an City. Furthermore, an increasing Al level has been detected in the upstream watershed near Xi’an City in recent years, which might indicate another notable pollution source of Al.     

北京大气中异戊二烯的季变化、日变化形式及影响因素研究

对2005年北京大气中异戊二烯进行了一年的观测分析。结果表明,异戊二烯体积分数年平均值为0.58×10^-9,月平均值为0.1×10^-9～1.8×10^-9,7月最高,1月最低。春、秋、冬三季,异戊二烯日变化形式呈三峰形,分别在14:00、18:00、02:00;18:00、02:00、08:00;02:00、10:00、16:00出现峰值;夏季异戊二烯体积分数日变化呈现白天高夜晚低且在14:00出现峰值。夏季异戊二烯源排放主要由生物排放控制,其日变化形式受温度、辐射影响大;春季和秋季异戊二烯源排放受汽车尾气和生物排放共同控制,其日变化形式受汽车尾气影响大,温度、辐射也有一定影响;冬季异戊二烯源排放主要由汽车尾气控制,其日变化形式主要受汽车尾气影响。不同季节北京大气中的异戊二烯体积分数日变化形式与PM_2.5浓度日变化形式大致相同。     

Fluctuating asymmetry rather than oxidative stress in <Emphasis Type="Italic">Bufo raddei</Emphasis> can be an accurate indicator of environmental pollution induced by heavy metals

Oxidative stress (OS) and fluctuating asymmetry (FA) as risk markers for environmental stress are widely used to predict changes in the health and fitness of many animals exposed to pollutants. However, from the perspective of protecting declining amphibians, it remains to be verified which one would be a reliable indicator for amphibians exposed to long-term heavy metal pollution under natural conditions. In this study, the OS and FA of Bufo raddei exposed to natural heavy metal pollution were analyzed to determine which marker is more accurate for indicating heavy metal-induced stress. Three years of data were collected during the breeding season of B. raddei from Baiyin (BY), which has been mainly contaminated with Cu, Zn, Pb, and Cd compounds for a long period, and from Liujiaxia (LJX), which is a relatively unpolluted area. Unexpectedly, although significant accumulation of the four heavy metals was found in the kidney and liver of B. raddei from BY, the levels of superoxide dismutase, glutathione peroxidase, and malondialdehyde in these two organs were found to be irregular, with low repeatability in both BY and LJX. However, significant differences in the levels of FA were observed in B. raddei populations from these two areas over the past 3 years (P < 0.01). The degrees of FA in B. raddei populations from BY and LJX were assessed as degree 4 and 1, respectively. In short, this study suggested that FA was a more reliable and effective indicator than OS to monitor and predict long-term environmental stress on anuran amphibians.     

高速公路交通噪声预测模型探讨

针对我国当前广泛使用的2种高速公路噪声预测模型《06规范》预测模型与《09导则》预测模型在预测时比较研究,重点利用环境现状监测数据分别对2种模型验证与对比分析.结果表明,2种模型预测值与实测值相差3dB ～5dB,车流量＞ 300辆/h,《09导则》更接近实测值;在夜间车流量＜300辆/h,《06规范》更接近实测值,2种模型结合采用《06规范》计算的车速,距离衰减考虑车流量的大小,在此基础上应用《09导则》,预测结果与实测值更为接近.     

State of rare earth elements in different environmental components in mining areas of China

China has relatively abundant rare earth elements (REEs) reserves and will continue to be one of the major producers of REEs for the world market in the foreseeable future. However, due to the large scale of mining and refining activities, large amounts of REEs have been released to the surrounding environment and caused harmful effects on local residents. This paper summarizes the data about the contents and translocation of REEs in soils, waters, atmosphere, and plants in REE mining areas of China and discusses the characteristics of their forms, distribution, fractionation, and influencing factors. Obviously high concentrations of REEs with active and bioavailable forms are observed in all environmental media. The mobility and bioavailability of REEs are enhanced. The distribution patterns of REEs in soils and water bodies are all in line with their parent rocks. Significant fractionation phenomenon among individual members of REEs was found in soil–plant systems. However, limited knowledge was available for REEs in atmosphere. More studies focusing on the behavior of REEs in ambient air of REE mining areas in China are highly suggested. In addition, systematic study on the translocation and circulation of REEs in various media in REEs mining areas and their health risk assessment should be carried out. Standard analytical methods of REEs in environments need to be established, and more specific guideline values of REEs in foods should also be developed.     

天津市中心城区集中供应管网末梢水的抗生素耐药基因污染特征研究

为了研究天津市中心城区集中供应管网末梢水的抗生素耐药基因(antibiotic resistance genes,ARGs)污染特征,采集了天津市中心城区6个采样点的管网末梢水样,分别采用微孔滤膜正压过滤法及核酸吸附-洗脱法富集水中细菌和胞外核酸后,利用实时定量PCR技术对15种胞内ARGs和胞外ARGs进行定量检测....     

An integrated method for safety pre-warning of complex system

In large-scale and complex industrial systems, unplanned outages and hazardous accidents cause huge economic losses, environmental contamination, and human injuries, due to component degradation, exogenous changes, and operational mistakes. In order to ensure safety and increase operational performance and reliability of complex system, this study proposes an integrated method for safety pre-warning to analyze the current safety state of each component and the whole system indicating hidden hazards and potential consequence, and furthermore predict future degradation trends in the long term.The work presented here describes the rationale and implementation of the integrated method incorporating HAZOP study, degradation process modeling, dynamic Bayesian network construction, condition monitoring, safety assessment and prognosis steps, taking advantage of the priori knowledge of the interactions and dependencies among components and the environment, the relationships between hazard causes and effects, and the use of historical failure data and online real-time data from condition monitoring.The application of the integrated safety pre-warning approach described here to the specific example of the gas turbine compressor system demonstrates how each phase of the presented method contributes to completion of the safety pre-warning system development in a systematic way.