胶州湾大肠菌群丰度变化及对环境污染的指示

VARIATION OF COLIFORM BACTERIA ABUNDANCE IN THE JIAOZHOU BAY AND ITS INDICATION TO ENVIRONMENTAL POLLUTION

采用MPN计数法对胶州湾大肠菌群丰度进行7年(84个月)连续监测,结果表明,大肠菌群丰度的周年变化明显,全年最高丰度与最低丰度相差约2.2倍。胶州湾大肠菌群丰度自2005—2009年明显下降,降幅达67%,说明胶州湾环境质量有所好转。研究还发现大肠菌群丰度变化具有明显的区域特征,河口区最高,湾内区最低,差异近11倍。大肠菌群丰度与环境因子的相关性分析表明,大肠菌群丰度变化与胶州湾海水中总氮、溶解有机碳、叶绿素a浓度,海水盐度及青岛市废水排放量均显著相关。

A 7-year monitoring of coliform bacteria abundance in the Jiaozhou Bay showed clear annual variations.On an annual basis,the maximum abundance of coliform bacteria appeared in September [（2.56±2.00）×104/L] and the minimum appeared in April [（1.17±0.77）×104/L],the maximum was about 2.2 times of the minimum.Analysis on the interannual variations showed that the coliform abundance declined by about 67% from（2.96±1.28） ×104/L（2005） to（0.97±0.81）×104/L（2009）,suggesting that the environmental quality of Jiaozhou Bay had improved.The distribution of the coliform bacteria exhibited regional patterns.The maximum abundance appeared in the estuary area [（5.42±2.47）×104/L],followed by the bay-mouth [（1.18±0.14）×104/L],the outer bay [（0.53±0.32）×104/L],and the inner bay [（0.50±0.11） ×104/L].The abundance in the estuary area was almost 11 times of the abundance from the inner bay.Correlation analysis between the abundance of the coliform bacteria and the environmental factors showed that the abundance was significantly correlated with sewage discharged in Qingdao,salinity,concentration of total nitrogen,dissolved organic carbon,and chlorophyll-a in the Jiaozhou Bay seawater.