南四湖水体氮磷及叶绿素空间分布特征

Spatial Distribution Characteristics of Nitrogen,Phosphorus and Chlorophyll in Water from Nansihu Lake

研究分析了南四湖水体氮、磷、叶绿素a含量及空间分布特征。结果表明,南四湖水质主要参数在各湖区的分布存在明显的非均一性。南阳湖水体TN、DTN、NH4＋-N、TP、DTP、PO43--P浓度均显著高于其他3湖区的,但独山湖、昭阳湖和微山湖水体不同形态氮、磷浓度间无显著差异;水体中DTN、NH4＋-N与TN以及DTP、PO43--P与TP浓度呈显著相关;南四湖水体中叶绿素浓度的分布呈现出较大的差异,南阳湖水体叶绿素浓度最高、微山湖的最低,叶绿素a浓度与TN/TP比值、pH值间呈显著的对数负相关,与不同形态氮、磷及COD浓度间呈显著的对数正相关。

The concentration and spatial distribution characteristics of nitrogen,phosphorus and chlorophyll a（Chla） in different zones from Nansihu Lake were studied.The results showed that values of primary water quality parameters in Nansihu Lake had a spatial heterogeneous distribution.The concentrations of total nitrogen（TN）,total dissolved nitrogen（DTN）,ammonium（NH＋4-N）,total phosphorus（TP）,total dissolved phosphorus（DTP）,and orthophosphate（PO3-4-P） in water from Nanyang Lake were significantly higher than those in other zones of Nansihu Lake,and the concentration of different forms of nitrogen and phosphorus between Dushanhu Lake,Zhaoyanghu Lake,and Weishanhu Lake had no significant difference.The trends of DTN and NH＋4-N concentration with TN,and of DTP and PO3-4-P concentration with TP were totally fitted by the linear equations respectively.The spatial distribution of Chla concentration in water from Nansihu Lake was obviously different,and Chla concentration was the highest in Nanyanghu Lake,and the lowest in Weishanhu Lake.The Chla concentrations were significantly negatively logarithmic correlated with values of pH,and the ratio of total nitrogen and total phosphorus.However,remarkably positively logarithmic relationships were observed between the concentrations of Chla and TN,DTN,NH＋4-N,TP,DTP,PO3-4-P,and chemical oxygen demand（COD）.