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Large variations in skeletal microarchitecture, and in the carbon and oxygen isotopic composition of the skeleton, exist within single calices and over the surfaces of single colonies of various species of West Indian (Jamaican) scleractinian reef corals. Rapidly extending parts of individual colonies are depleted in both C13 and O18 regardless of the abundance of zooxanthellae in the overlying tissues. We suggest that this relationship is due to active translocation of organic compounds to sites of rapid calcification. Considerable variation in isotopic composition is found in skeletons of different specimens of the same species even when the skeletons are sampled in a consistent manner, come from the same locality and depth, and have a comparable growth history. The isotopic composition of the scleractinian skeleton is vastly more complex than has heretofore been realized.  相似文献   
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鲤鱼对三种硝基芳族化合物的摄取、释放和生物富集   总被引:7,自引:0,他引:7  
赵晓明  郎佩珍 《环境化学》1994,13(5):433-438
用第二松花江水和鱼体中多次检出的三种硝基芳族化合物来分别测定鲤鱼体中的生物富集系数(BCF),摄取和释放动力学参数,以及在肌肉、肠、肝和鳃等组织中的分布。试验在半静态条件下进行。硝基芳族化合物在鲤鱼体内的释放可用双区一级动力学模型很好地描述。鲤鱼对2,4-二硝基甲苯和对硝基氯苯的富集过程中发现有未知的代谢产物生成。  相似文献   
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This contribution highlights the role and importance of ecotoxicology in regulatory decisions of chemicals legislation focussing on the responsibilities of the German Federal Environmental Agency (UBA). Therefore, organisational structures and processes relevant for making decisions concerning the risks of chemicals to men and the environment are described. As any regulatory decision starts with scientific findings, a brief overview of UBA’s activities with regard to own research and to initiate research in the area of ecotoxicology is provided. In addition, the vast importance of standardisation and international harmonisation of guidelines for testing and assessment of chemicals is illustrated, including the time- and ressource consuming character of these harmonisation processes. Subsequently, the involvement of regulatory decision making in intense and controversial scientific and political debates is emphasised. The transparency of these discussions and the independence of science is critically addressed in this context. In a final chapter the job requirements and options for qualification in Germany are described, ending up with a brief summary of the positive experiences with UBA’s contribution to the new advanced training course in ecotoxiciology realised by GDCh/SETAC GLB. A summary of the discussions on these different topics emphasises the specific challenge in regulatory ecotoxicology: To generate knowledge relevant for decision making, while acting in an area of conflict between scientific demands and economical as well as political interests.  相似文献   
116.

Goal and Scope

The constant increase of traffic and the rising energy and material consumption both in industry and trade as well as in private households mean a constant challenge to environmental protection and to the air pollution control. With the commencement of the Federal ambient pollution control act in April 1974, the legal basis for the monitoring of air pollution was created. In future, the limit values laid down in the Council Directive 1999/30/EG, 2000/69/EG and 96/62/EG, will be valid. In town and regional planning there is a great demand for a simple index to evaluate the air quality. From the available data of PM10, NO2, O3, CO, SO2, trends of the air quality will be derived.

Methods

The indices LQI and TLQ suggested by Mayer et al. (2002) were calculated for selected stations of the air pollution monitoring network (ZIMEN) in Rhineland-Palatine. All analysis are based on hourly recorded value, Mean values and frequency distributions are used for the interpretation. Furthermore, the characteristics and trends of the indices under different weather conditions were examined and discussed.

Results

The examination figures out that the air pollutions indices at all stations show similar patterns in the period between January 2001 and December 2002. Neither the LQI, nor the TLQ shows an annual variation. Existing variations are mainly controlled by the general weather situation and the air temperature. High values of the indices appear at extremely high or low mean daily air temperature. The absolute value of the air pollution index is determined by local pollution factors.

Outlook and Recommendations

Both indices are well suitable to evaluate the air quality and to assess the effects of state-aided measures for air pollutant control. Therefore, the indices TLQ and LQI should be published as an additional information in the world wide web.  相似文献   
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工业的发展既要最大限度地满足人们物质与文化生活的需要,又要创造人类与自然之间和谐的生产与生活环境。从可持续发展的角度出发,分析了平顶山这一典型资源型城市工业发展的条件和现,针长期以高耗资源和粗放经 特征的发展模式,提出了其工业可持发展 途径,实现结构合理化及优化投资环境;建立资源节约型,在环境质量和资源基础上都可以长期承受的新型工业发展模式。  相似文献   
120.
本文论述了我国铅锌矿产资源储量、分布特点和消费现状,并预测了我国铅锌金属的需求量.  相似文献   
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