Polybrominated diphenyl ethers (PBDEs) and indicator polychlorinated biphenyls (PCBs) in marine fish from four areas of China

The levels of polybrominated diphenyl ethers (PBDEs) and indicator polychlorinated biphenyls (PCBs) were determined in marine fish from four areas of China (South China Sea, Bohai Sea, East China Sea, and Yellow Sea) using GC/NCI-MS and GC/ITMS, respectively. Total concentrations of eight PBDEs (BDE-28, 47, 99, 100, 153, 154, 183 and 209) in all samples ranged from 0.3 ng g⁻¹ ww (wet weight) to 700 ng g⁻¹ ww, with median and mean values of 85 ng g⁻¹ ww and 200 ng g⁻¹ ww, respectively. BDE-209 and BDE-47 were the major congeners in all samples, contributing 54% and 19% to the total concentration, respectively. The sum of seven indicator PCB levels (CB-28, 52, 101, 118, 138, 153, and 180) ranged from 0.3 ng g⁻¹ ww to 3.1 μg g⁻¹ ww, with median and mean values of 6.4 ng g⁻¹ ww and 398 ng g⁻¹ ww, respectively. High contributions of CB-138 (32%) and CB-153 (25%) were found in all samples. In general, pollutants measured in this study were at high levels when compared with previous studies from other regions in the world. The relative abundance of BDE-209 may suggest that deca-BDE sources existed in studied area. And principal component analysis (PCA) showed that there were other PBDE sources in Yellow Sea. The pattern and PCA showed that PCB pollutions came from similar sources in the studied areas. In addition, concentrations of ∑₇PBDEs (u/209) were strongly correlated with those of ∑₇PCBs in all fish (r = 0.907, n = 44).     

Sequestration of organochlorine pesticides in soils of distinct organic carbon content

In the present study, five soil samples with organic carbon contents ranging from 0.23% to 7.1% and aged with technical dichlorodiphenyltrichloroethane (DDT) and hexachlorocyclohexane (HCH) for 15 months were incubated in a sealed chamber to investigate the dynamic changes of the OCP residues. The residues in the soils decreased over the incubation period and finally reached a plateau. Regression analysis showed that degradable fractions of OCPs were negatively correlated with soil organic carbon (SOC) except for α-HCH, while no correlation was found between degradation rate and SOC, which demonstrated that SOC content determines the OCP sequestration fraction in soil. Analysis of the ratio of DDT and its primary metabolites showed that, since it depends on differential sequestration among them, magnitude of (p,p′-DDE + p,p′-DDD)/p,p′-DDT is not a reliable criterion for the identification of new DDT sources.     

基于相对资源承载力的青岛市主体功能区区划

本文根据相对资源承载力研究方法,以全国作为参照区域计算了2005～2008年青岛市主要辖区相对自然资源承载力、相对经济资源承载力和综合承载力.分析结果表明:①对于相对自然资源承载力而言,平度市处于富余状态;莱西市处于临界状态;胶州市、即墨市、胶南市处于超载状态:青岛市市区则处于严重超载状态.相对自然资源承载力序列(由富余到超载):平度市>莱西市>胶州市>胶南市>即墨市>市区.②青岛市各辖区相对经济资源承载力全部处于富余状态,其中市区的相对经济资源承载能力最大.相对经济资源承载力序列(由富余到超载):市区>胶州市>胶南市>即墨市>藁西市>平度市.③青岛市各主要辖区综合承载力全部处于富余状态,且基本保持稳定.综合承载力序列(由大到小):市区>平度市>即墨市>胶州市>胶南市>莱西市.在此基础上.本文对青岛市2005-2008期间主要辖区的主体功能区进行了区划,结果显示青岛市所辖6市区均属于优化开发区,在"十二五"期间.产业调整与优化仍是区域可持续发展的重中之重.     

Investigation of PM2.5 pollution during COVID-19 pandemic in Guangzhou, China

The COVID-19 pandemic has raised awareness about various environmental issues,including PM_2.5 pollution.Here,PM_2.5 pollution during the COVID-19 lockdown was traced and analyzed to clarify the sources and factors influencing PM_2.5 in Guangzhou,with an emphasis on heavy pollution.The lockdown led to large reductions in industrial and traffic emissions,which significantly reduced PM_2.5 concentrations in Guangzhou.Interestingly,the trend of PM_2.5     

Effects of labelled meaning on the affective quality of housing scenes

A series of studies examined the effects of labelled meaning on affective response to housing scenes. Students at Ohio State University assessed their feelings towards imagined housing (public or private) and cities (Memphis, Houston and San Francisco). Expected differences in the affective quality were found. Responses to color photographs of specific housing scenes labelled as either private condominiums or public housing were obtained. Differences in scene-affect as a function of labelled meaning were found. Responses to housing scenes labelled as located in either Memphis, Houston or San Francisco revealed no differences in scene-affect as a function of label meaning. This latter finding was confirmed in a non-repeated measure examination. Differences in the fittingness, potency or relevance of the information provided may account for the pattern of findings.     

Wetland development trends in coastal North Carolina,USA, from 1970 to 1984

Coastal wetlands are a valuable resource to North Carolina, USA, representing important habitat for marine organisms and providing flood control areas and buffer zones from marine storms. An analysis of wetland development trends in coastal North Carolina from 1970 to 1984 was conducted using over 3000 files containing 15 years of permitting records. The total amount of coastal wetland area altered due to authorized development under the Coastal Area Management Act (CAMA), the Dredge and Fill Law, and Section 404 of the Federal Water Pollution Control Act is 1740 ha. This represents nearly 2% of the salt marsh wetlands along the coast of North Carolina. The number of permits issued steadily increased during the 1980s; however, the total amount of wetland loss decreased each year. A few large projects in the early 1970s accounted for nearly 70% of all wetland area developed during the 15-year period. Nearly two-thirds of all projects involving wetland destruction involved impacts on high marsh ecosystems. Bulkheads, canals, and filling activities made up 80% of the projects requiring permits; 62% of the permits were issued to private landowners, but this group accounted for only 16% of the losses of wetland area. Utility companies, which accounted for less than 1% of the permits issued, were responsible for 46% of the permitted wetland loss during the 15-year study period. Future studies should address agriculture and forestry practices which are exempt under CAMA laws and therefore their effects on wetland alteration have not been quantified.     

New federalism and state implementation of the Clean Water Act

An important goal of the Reagan administration has been to shift responsibility for many public programs from the US federal government to the states. This New Federalism seeks to restore a proper balance to the federal system and to ensure an effective working partnership between the states and the federal government. Such a partnership is especially important for many environmental laws because these laws often give states primary responsibility for the control and abatement of pollution.This research examines the extent to which the Reagan administration has succeeded in improving intergovernmental environmental relations in terms of state implementation of the Clean Water Act. Data from a 1985 survey of directors of state water quality control programs are compared with responses to a similar survey that the US General Accounting Office conducted in 1979. The latter survey found considerable dissatisfaction on the part of state directors with the quality of their relations with the US Environmental Protection Agency. Although some improvement can be noted between 1979 and 1985, the Reagan administration's efforts to improve intergovernmental relations appear to have been of limited consequence, to the possible detriment of effective implementation of the Clean Water Act.     

事故致因的突变模型

在众多论述伤亡事故致因的理论中，都没有解释为何系统元素的连续变化引起系统状态的突变（事故），以及人、物因素在这种突变过程中的作用。本文引入突变理论这一数学工具，指出系统内某些元素的连续变化导致系统状态的突然改变，较好地解决了这个问题，通过建立事故致因突变模型，提出了提高系统安全性的原则。     

我国矿井环境模拟和控制技术的研究进展

计算机技术的迅速发展,极大地推动了矿井动态通风系统定量分析的研究。本文介绍了我国近年来在矿井火灾时期井下状态模拟和最优控制方面应用新技术获得的进展,并对各种定性及定量分析方法进行比较和评价。文中对建立矿井火灾时期救灾决策系统的研究方向提出了建议,以便能尽快的为矿井灾变时期的救灾指挥决策的实际应用服务。     

纺织工业安全生产特点及安全对策管理

简要分析了纺织工业安全生产的特点及安全管理的难点,从而针对性地应用了安全对策管理,并取得一定成效。