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Background and Scope

The marine shipping lanes have become the most important path for the invasion of foreign aquatic organisms. The increasing global trade results in an increase in the number of marine vessels. Without any protective measures, with every ship carrying foreign organisms the risk of biological invasions will rise.

Results

The International Martime Organization (IMO) of the United Nations developed a convention to reduce the transfer of organisms with ballast water. After the entry-into-force of this convention the fleet of the world has to be equipped with effective ballast water management technology before 2016. This article discusses potential options for action. To comply with the limit values of the ballast water convention, the current state of the art demands the use of active substances. Any decision on the approval of active substances used for ballast water treatment and the environmental impact assessment lies with the IMO. Proposed to day are UV-radiation, active chlorine, active oxygen, the creation of biocides through electrolysis and a change in gases contained in the ballast water. The technologies and the potential risks are presented.

Conclusions

Despite the introduction of an approval procedure by IMO any reliable assessment of the real risks involved in the use of biocides is impossible, as the risk assessment approaches have still to be developed. On the regulatory level, the main focus in data requirements for the risk assessment is on a comprehensive testing of the toxic potential of the biocides proposed. Strategies for the identification and evaluation of the chemical resulting from the treatment of limnic, marine and brackish water are not fully developed. An integrating assessment of risks involved in the introduction of foreign organisms versus the toxic effects of the substances used or created during treatment is still missing.  相似文献   
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Environmental functions as a unifying concept for ecology and economics   总被引:6,自引:0,他引:6  
Summary In spite of the increased awareness about many environmental problems, degradation and pollution of the natural environment by human actions still continue on a large scale. Some of the main reasons for man's continued abuse of the natural environment are the short-term nature of the economic planning process, which largely ignores the negative long-term effects of economic production on the environment (e.g. pollution), and the fact that the pricing system mainly concentrates on man-made goods and services while considering most natural resources to be free goods.This paper argues that environmental functions (i.e. natural goods are services) are at least as important to human welfare as man-made goods and services and should, therefore, be included in economic accounting procedures. To this end, it is suggested to replace the term natural resources by the concept of environmental functions and, efforts should be undertaken to increase our understanding of the ecological and socio-economic benefits of environmental functions to human society. Only when ecological principles become an integral part of economic planning and political decision-making is there a chance of achieving a happy global village based on harmony between man and nature.Rudolf S. de Groot is an environmental consultant and a Ph.D candidate in environmental planning and management in the Nature Conservation Department of the Agricultural University Wageningen. As a member of the IUCN Commission on Environmental Planning he is involved in the activities of the European Committee for National Conservation Strategies, to implement, monitor and update National and European Conservation Strategies.  相似文献   
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von Götz N  Richter O 《Chemosphere》1999,38(6):1401-1407
The degradation behaviour of bentazone in 14 different soils was examined at constant temperature and moisture conditions. Two soils were examined at different temperatures. On the basis of these data the influence of soil properties and temperature on degradation was assessed and modelled. Pedo-transfer functions (PTF) in combination with a linear and a non-linear model were found suitable to describe the bentazone degradation in the laboratory as related to soil properties. The linear PTF can be combined with a rate related to the temperature to account for both soil property and temperature influence at the same time.  相似文献   
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