Variety of Chlorophyll-a and its Correlations with Environmental Factors Before and After Algal Bloom

Many present studies on the relationships between chlorophyll-a(Chl-a) and water-quality factors are based on the data after algal bloom.In this paper,the data of a reservoir in south China,from February 2003 to December 2009,were used to investigate the temporal variety of chl-a before and after the algal bloom in 2006.The correlations between Chl-a and TN,TP,pH,SD and DO were also investigated.Results indicate that the maximum concentrations of Chl-a are in the summer of 2003 to 2005.Algal bloom is likely to occur in the winter from 2007 when the maximum values of Chl-a are determined.There are no significant correlations between Chl-a and the engaged water-quality factors before the algal bloom in 2006;after that,the correlations increase significantly except for TN.There are direct or indirect linear relationships between Chl-a and TP,SD,pH and DO.