增加紫外辐射对海洋生态的影响

How Might Enhanced Levels of Solar UV-B Radiation Affect Marine Ecosystems

环境科学家面临的一项挑战性任务是如何根据各种生物和生物过程的研究来确定外部环境变化对自然生态系统的影响。评价紫外辐射大量增加对海洋环境产生的潜在影响是具有挑战性的任务。大量的紫外线辐射对海洋生态系统影响范围很广,并涉及难于观察的细微变化。特别引人注意的是由于长时间的辐射使许多海洋生物过程可能持续发生变化。另外,由于对海洋生态系统缺少缓冲辐射的措施和方法,使辐射的压力和影响范围正在加剧。如果承认上述推断,那么重要的问题就是用实验来验证这种推断。在本文中。

One of the most challenging tasks facing environmental scientists is to determine the likely consequences of an external change for complex natural ecosystems on the basis of observations of the impact on individual orga- nisms or processes.Assessing the potential impacts of enhanced solar UV-B radiation on the marine environment presents such a challenge.The potential UV-B stress is broad-scale;the response of marine ecosystems involves many spatial and temporal scales,and also involves subtle changes that may be difficult to detect.A particularly acute concern exists,however,for lasting changes-changes made possible because of long residence times for many oceanic processes,as well as the lack of mitigating measures given the spatial extent of both stress and effects.Thus,acknowledging the speculative nature of extrapolations,the potential problems are of a quality requ ring significant a priori examination.In this paper,I suggest several types of ecological changes of concern.The examples-includingpossibleeffects on food webs,fisheries,and biogeochemical cycles-are chosen to illustrate the scope and urgency of the problem.