中文摘要：

对1980--2007年广东沿海赤潮灾害历史资料进行统计分析，研究赤潮灾害的时空分布规律和赤潮肇事种的变化规律。结果表明，广东沿海赤潮灾害总体呈上升趋势，发生频率不断增加；赤潮高发季节由过去的春季扩展到春夏秋冬季；赤潮发生海域和影响范围不断扩大；鱼毒性藻类和有毒藻越来越频繁地引发赤潮；引发赤潮灾害的生物种类不断增多，由甲藻和硅藻引发的赤潮减少，而由针胞藻类、定鞭藻类和纤毛虫类引发的赤潮明显增多。研究表明，赤潮生物种类繁多和日益增多的海洋污染可能是广东沿海赤潮灾害频发的原因。

英文摘要：

Based on the historical analysis of 30 years＇ data accumulated on the harmful algal blooms （ HAB ） in Guangdong coastal areas, the paper has made a comprehensive survey and categorized the regularities of the HAB distribution and succession of causative organisms. The results of our survey and analysis indicate that the frequency of HAB occurrences in Guangdong coasts tends to rise significantly since 1980, especially during the seven years from 2000 to 2007, the number of HAB events has increased over t0 times each year almost. The high season of HAB occurrence has been shifted from spring in 1980s and 1990s to the four seasons from 2000 to 2007. Furthermore, the areas and locations affected by HAB events have also been extended. Before 1995, only 2 events were recorded in the west coast of Guangdong, and no record in the east coast of Guangdong. But the number of HAB events has been significantly increased in the eastern and western coasts of the province since 2000. The HAB incidents ever recorded in the above-said areas was 22 and 12, respectively, during the said period. In addition, the proportion of toxic and detrimental events has also been mushrooming. Whereas there were no recordings with toxic events in 1980s, the number has been rising gradually since 1990s. Fish-killing events have also turned up more and more frequently, whose number increased from l0 in 1980s to 44 in 2000s. Moreover, the constitution of HAB causative species has also been varied. For example, whereas the percentage of the dinoflagellates blooms drops from 70% in 1980s to 56% in 1990s and to 33% during the period of 2000- 2007 and diatom blooms drops from 32% in 1990s to 26% during 2000 - 2007, the blooms of Raphidophyceae, Haptophyceae and Ciliates have increased, especially, during the same period. Therefore, we strongly believe that it is imperative to study and disclose the myth that has caused HAB occurrences in the coastal areas of Guangdong province on the basis of analysis of the data collected in the past 30 years.