The Relation Between Differences of Red Tide Frequency and Economic Development along the Coasts of Guangdong
广东沿海赤潮发生频率差异与城市发展的关系

Red tides are one of the main coastal catastrophic events of Guangdong Province, China. The comparison between the numbers of red tide events and the development indexes of cities along the coasts of the province shows that the regional differences in red tide outbreaks has a close relation to those in the coastal urban developments. The cause for an initiation of red tide blooms may be natural ones, but wastewater caused by the fast development of population, industry and aquiculture of the coastal cities enhanced the blooms. It may explain why the two periods of frequent outbreaks of the red tides from 1998 to 2000 matched the urban developments in the coastal areas of Guangdong not only spatially but also temporally. The red tides in the first period were restricted only on the coasts of middle Guangdong, where the urbanization were rapider than the other coastal areas of the province. In second period, fast increments in the development of the coastal cities in east Guangdong leaded to an increase in occurrence of red tides in the sea areas of the same coasts.