环境生态系统散落核素示踪研究新进展

PROGRESS ON FALLOUT RADIONUCLIDES AS TRACERS IN ENVIRON-ECOLOGICAL SYSTEMS

环境生态系统中的放射性核素既具有生态毒性 ,对生物和人体健康产生重要影响 ,又具有稳定的衰变函数和输入通量 ,对环境生态系统具有重要示踪价值。人类可利用放射性核素来认识环境生态系统 :1环境生态系统中放射性核素的基准 :放射性强度与环境生态系统之间的平衡关系 ;2环境生态系统中放射性核素的行为 :在环境生态系统不同宿体和组分间的运移关系。

The radionuclides in environ ecological systems are important for numbers of reasons. These include the potential radiological impact on biota and human health, and their use as tracers for environmental processes. Therefore, man can make use of radionuclides to know the ecosystem. Important aspects include: (1) radionuclide criteria in the environments and the ecosystem: equilibrium relationship between the radioactive ratio and the ecosystem, or the important significance of environmental radionuclides in the ecosystems; and (2) radionuclide behavior in the environments and the ecosystem: the transfer relationships of radionuclides between different components of the ecosystem. In order to understand the impacts of bio geochemical processes in different ecosystems, it is essential to investigate the variety of radionuclide activity, and the interactions with the environment of all stages. The VII International Congress of Ecology was organised by the International Association for Ecology (INTECOL) in conjunction with the Italian Ecological Society (SITE). It was held in Florence, Italy on 19～25 July, 1998. With support from the Program Committee, we established a Symposium on Radionuclides in Ecological Systems(RNES)organised as below. On this symposium, the discussion focuses on the geochemical behaviours of 210 Pb, 137 Cs and 7Be, as three fallout radionuclides with different originating. This presentation is concerned with recent progress on the dating lake sediments by 210 Pb and 137 Cs, and the bio geochemical behaviors of the 210 Pb, 137 Cs and 7Be in the terrestrial and aquatic ecosystems. With the fallout radionuclides such as 210 Pb, 137 Cs and 7Be are of increasing importance to a wide range of environmental and ecological programs, in order to know their role in the evolution of ecosystems by acting as propellers of genetic variation, it is essential to establishing a global database for environmental radionuclides