Temporal and Spatial Distribution of Chlorophyll-a in Yao Lake and Its Correlation with Environmental Factors

According to the analysis on water quality monitoring indexes data of Yao lake in Jiangxi from May 2010 to April 2011,the nine monitoring sites were classified into two kinds of areas using Q-type analysis method,based on which the temporal and spatial distribution rules of chlorophyll-a were investigated.The results showed that the annual average content of chlorophyll-a was 25.82 mg / m3;and the variation range in the monitoring sites were 1.59~142.68 mg / m3.From the view of temporal distribution,on the whole,chlorophyll-a content increased continuously in spring,summer and autumn,and reduced in winter.Chlorophyll-a content was significantly different in different sites;and it decreased continuously with the decrease of nutrient content.The correlation between chlorophyll-a content and environmental factors was analyzed using Pearson index method.There was high positive correlations between chlorophyll-a content and water temperature(or dissolved oxygen),nutrient(total phosphorus,nitrite nitrogen,ammonia nitrogen),pH;while high negative correlation between chlorophyll-a content and transparency.