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31.
The rapidly developing Asian countries may face threatening environmental contamination, that however remains largely unassessed. We studied persistent trace elements in three wetlands, Poyang Lake, relatively unpolluted, and Tai Lake, and Pearl River Delta, selected as hotspots of pollution in Central China. We adopted as indicator the Little Egret, a widespread colonial waterbird, and during 1999 and 2000 we collected and analysed the same samples as for a parallel study we conducted in Pakistan, e.g. eggs, body feathers of chicks, prey spontaneously regurgitated by the chicks, and sediments at the areas most used by foraging egrets. The levels of trace-metals at our three study areas were similar, or within the range, of those found in the few other studies for East Asia, with few exceptions. The concentrations of the various elements were below the threshold that may affect the survival or reproduction of the birds, and even the highest concentrations relative to background, i.e. Se in eggs, and Hg in feathers at Pearl Delta, do not pose toxic hazards. In sediments, the levels of trace elements were lower than the critical levels assumed for contaminated soil, except for alarming high levels of As at Poyang. These results do not confirm our expectation, that Poyang was relatively uncontaminated, while Tai and Pearl were polluted. Although trace metal concentration differed significantly among the three study areas, these differences were minor and were not consistent among elements and samples. The bioaccumulation ratios from sediments through prey, feather and egg, were consistent with our previous findings for Pakistan. Only Hg exhibited high bioaccumulation, while Se and Zn had low accumulation, and the other elements no accumulation. This reasserts that feathers of predators such as egrets, may be more sensitive indicators of environmental contamination for the elements subject to bioaccumulation, whereas the sediments or the organisms low in the food chain are better indicators for the other elements.  相似文献   
32.
科学研究和评估工作推动了国际应对气候变化进程,并加大了各国行动力度。更多的科学证据表明人类活动是造成全球气候变暖的主要原因;气候变化影响、适应和脆弱性研究范围不断扩展和深化,区域甚至次国家级层面的问题受到高度关注;2℃温控目标的实现已然成为共识,政策协调与集成及相关政策在不同领域的协同作用成为研究的热点。未来中国应对气候变化需要在四个方面进一步开展研究和采取行动:1加强不同学科和领域的研究工作,围绕与实现温升控制1.5℃、土地利用、海洋以及城市相关问题开展专题研究。2加强国内绿色低碳转型和国际谈判的战略研究。3构建气候服务体系,以灾害风险管理为抓手,提升气候变化适应水平。4通过构建能源互联网实现能源变革,加快推进国内能源革命和经济发展的低碳转型。  相似文献   
33.
A solid-phase microextration-based sampling method was employed to determine the concentrations of 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (DDT) and its metabolites, 1,1-dichloro-2,2-bis(p-chlorophenyl)ethane (DDD), 1,1-dichloro-2,2-bis(p-chlorophenyl)ethene (DDE) and 1-chloro-2,2-bis(p-chlorophenyl)ethene (DDMU), in two estuarine bays, Daya Bay and Hailing Bay, of South China. Six DDT components including p,p′-DDT, o,p′-DDD, p,p′-DDD, o,p′-DDE, p,p′-DDE, and p,p′-DDMU were detected in Hailing Bay, while only p,p′-DDD was found in Daya Bay. p,p′-DDD was the most abundant DDT component in both bays, sharply different from the previous finding in the water column of the Palos Verdes Shelf, California, USA that p,p′-DDE was prevalent. In addition, the occurrence of p,p′-DDMU (with a range of 0.047-0.21 ng/L in Hailing Bay) has not been reported around the globe, and its presence in our study region appeared to stem from dehydrochlorination of p,p′-DDD, favored under aerobic conditions, but further investigations are clearly needed to confirm the mechanism for generation of DDMU in estuarine environments.  相似文献   
34.
The wide application of new information and communication technologies (ICTs) has been argued to be critical to business success of small and medium-sized enterprises (SMEs), especially to those in the developing countries. Drawing upon existing literature, this article will examine the determinants of ICTs application in SMEs in China based on data collected from interviews with top managers and/or owners of 70 SMEs. We identify 20 factors affecting ICTs application in SMEs in China and divide them into four broad categories, namely pressures, firm specific factors, technical factors and local milieu. We also pay special attention to the Chinese business environment affecting ICTs application. Our analysis shows that local ICT infrastructure, external pressures from competitors and ICT knowledge of employees are the determinants of Internet application by SMEs, while product characteristics and market target are important factors of e-commerce adoption.  相似文献   
35.
2007年中国安全生产事故与自然灾害状况   总被引:2,自引:2,他引:0  
综述了2007年中国安全生产事故状况和自然灾害情况.2007年中国共发生各类安全生产事故506 376起,死亡101 480人,同比分别减少19.3%和10.1%.非煤矿山共发生伤亡事故1 861起、死亡2 188人,同比分别下降0 6%和3.9%.火灾发生15 9万起,死亡1 418人,受伤863人,直接财产损失9 9亿元.共发生森林火灾9 260起,草原火灾248起.2007年各类自然灾害共造成39 777 9万人(次)不同程度受灾,因灾死亡2 325人; 农作物受灾面积4 899万hm2,上升19 2%,其中绝收面积575万hm2,上升6.2%.因灾直接经济损失2 363亿元,比2006年下降6.5%.安徽、四川、河南、湖南、云南、重庆、浙江、陕西等地受灾较为严重.全国因气象灾害共造成经济损失约2 342亿元.2007年共发生风暴潮、海浪、海冰、赤潮和海啸等灾害性海洋过程163次,造成直接经济损失88 37亿元,死亡(含失踪)161人.地质灾害共发生25 364起,死亡598人,造成直接经济损失24 75亿元.大陆地区共发生5级以上地震17次,地震灾害造成死亡3人,直接经济损失20.19亿元.结果表明,2007年中国安全生产事故的发生较2006年有所缓和,自然灾害状况也较2006年轻.  相似文献   
36.
In the late 1990s China started to expand its market economic reform to the public sector, such as water services. This reform led to major changes in urban water management, including water tariff management. The reforms in water tariff management relate not only to tariffs, but also to the decision-making on tariffs. Water tariff decision-making seems to move away from China's conventional mode of highly centralized and bureaucratic policy- and decision-making. The legalization, institutionalization and performance of public hearings in water tariff management forms a crucial innovation in this respect. This article analyzes the emergence, development and current functioning of public hearings in water tariff setting, and assesses to what extent public hearings are part of a turning point in China's tradition of centralized bureaucratic decision-making, towards more transparent, decentralized and participative governance.  相似文献   
37.
为查明华东某铀矿区稻米中放射性核素铀污染现状及健康风险问题,测定铀矿区和对照区共136件稻米样品中放射性核素U含量,采用单因子污染指数法评价放射性铀污染,并开展U元素健康风险评价。结果表明:(1)研究区稻米中U含量平均值为1.46 ng·g~(–1),各亚区稻米中U含量平均值从大到小顺序为:开采矿井区水冶场区含矿未采区废弃矿井区江西省背景值对照区;(2)稻米单因子污染指数为1.25,属于轻度污染。其中,开采矿井区和水冶厂区为轻度污染,废弃矿井区和对照区未受污染;(3)首次计算提出江西省大米U元素致癌风险最大斜率系数为1.04×10~3(d·kg)·mg~(–1)。各亚区稻米中成人和儿童致癌风险指数高低顺序均为:开采矿井区水冶厂区含矿未采区废弃矿井区对照区。儿童直接饮食稻米具有一定的致癌风险;开采矿井区和水冶厂区的成人存在一定致癌风险,含矿未采区和废弃矿井区以及对照区均无致癌风险。  相似文献   
38.
Based on the China high resolution emission gridded data (1 km spatial resolution), this article is aimed to create a Chinese city carbon dioxide (CO2) emission data set using consolidated data sources as well as normalized and standardized data processing methods. Standard methods were used to calculate city CO2 emissions, including scope 1 and scope 2. Cities with higher CO2 emissions are mostly in north, northeast, and eastern coastal areas. Cities with lower CO2 emissions are in the western region. Cites with higher CO2 emissions are clustered in the Jing-Jin-Ji Region (such as Beijing, Tianjin, and Tangshan), and the Yangtze River Delta region (such as Shanghai and Suzhou). The city per capita CO2 emission is larger in the north than the south. There are obvious aggregations of cities with high per capita CO2 emission in the north. Four cities among the top 10 per capita emissions (Erdos, Wuhai, Shizuishan, and Yinchuan) cluster in the main coal production areas of northern China. This indicates the significant impact of coal resources endowment on city industry and CO2 emissions. The majority (77%) of cities have annual CO2 emissions below 50 million tons. The mean annual emission, among all cities, is 37 million tons. Emissions from service-based cities, which include the smallest number of cities, are the highest. Industrial cities are the largest category and the emission distribution from these cities is close to the normal distribution. Emissions and degree of dispersion, in the other cities (excluding industrial cities and service-based cities), are in the lowest level. Per capita CO2 emissions in these cities are generally below 20 t/person (89%) with a mean value of 11 t/person. The distribution interval of per capita CO2 emission within industrial cities is the largest among the three city categories. This indicates greater differences among per capita CO2 emissions of industrial cities. The distribution interval of per capita CO2 emission of other cities is the lowest, indicating smaller differences of per capita CO2 emissions among this city category. Three policy suggestions are proposed: first, city CO2 emission inventory data in China should be increased, especially for prefecture level cities. Second, city responsibility for emission reduction, and partitioning the national goal should be established, using a bottom-up approach based on specific CO2 emission levels and potential for emission reductions in each city. Third, comparative and benchmarking research on city CO2 emissions should be conducted, and a Top Runner system of city CO2 emission reduction should be established.  相似文献   
39.
Liu X  Xu L  Chen Q  Sun L  Wang Y  Yan H  Liu Y  Luo Y  Huang J 《Chemosphere》2012,87(5):549-556
We collected three ornithogenic coral sand sedimentary profiles from Jinyin Island, Jinqing Island and Guangjin Island of Yongle archipelago, South China Sea and reconstructed the deposition flux of anthropogenic Hg over the past 700 years in the study area. On the whole, the anthropogenic Hg flux is relatively low; it remained at a low level before the Industrial Revolution with a small peak at about 1450-1550 AD, which may record the enhanced metallurgy activity in Ming Dynasty of China. During the 20th century, the deposition flux of anthropogenic Hg increased rapidly, but two troughs occurred during the periods around 1940s and 1970s, corresponding to the economic depression caused by World War II, Civil War in China (1945-1949), and the Culture Revolution (1966-1976) in China. Since the 1970s the deposition flux of anthropogenic Hg has been persistently increasing, apparently the result of fast economic development in East and Southeast Asia countries around South China Sea.  相似文献   
40.
在2004—2007年旅游统计数据的基础上,运用主成分分析法对西部地区旅游业发展水平进行了综合评价。结果表明,尽管西部地区旅游资源优势明显,但旅游业发展的整体水平还较低,旅游资源优势尚未充分转化为经济优势,且各地区旅游业发展水平差异较大。基于上述分析,结合西部地区实际情况和旅游业的未来发展趋势,提出加快西部地区旅游业发展的对策和建议。  相似文献   
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