Relationships Between Eutrophication And The Occurrences Of Red Tide In Red Tide-Monitoring Area Of Sandu Bay

We compared the space-time distribution of temperature,salinity,DIP,DIN,COD, the density of phytoplankton cells of Funing and Sansha bay seawater,which belong to Tide-Monitoring Area of Sandu Bay.Results shows that,DIP,DIN,eutrophication index(E)and organic pollution index(A)in Sansha bay are higher than those which in Funing bay during the most of the time in a year.The annually average of temperature, salinity,COD and the density of phytoplankton cells are higher in Funing bay.Monitoring data in 9^thMay to 13^thMay 2007 in Xiapu which located in Funing bay were chosed.The results indicated that,the degree and structure of eutrophication are the matter bases and necessary condictions for red tide produced;but eutrophication of seawater is only one of the reasons that red tide occurance,at the same time,N/P＞16 isn't the decisive factor in Funing Bay red tide produced.Based on SPSS13.0,40 samples were chosed in the time red tide high frequency happened.We use stepwise regression to filter the environmental variable,the density of phytoplankton and chl-a were set to dependent.Results shows that,when the density of phytoplankton become dependent,chl-a,N/P,COD and dependent have a distinct linear regression relationship;in another aspect,there was a linear corelation between Do,T, diaphaneity and chl-a.Finally,chl-a,T,diaphaneity can be used to precise forecast multiplication of red tide species,also it can cut down the work of analyzing overfull monitoring data,improve ocean environmental monitor efficiency and red tide precise forecast.