白洋淀柱状沉积物磷形态及其分布特征研究

Phosphorus Forms and Its Distribution Characteristics in Sediment Cores of Baiyangdian Lake

应用淡水沉积物磷形态的标准测试方法（SMT）,调查了白洋淀6个典型湖区柱状沉积物中的磷形态分布、垂向及在两种沉积物粒级（砂土和粉砂/粘土）上的变化特征,分析了各形态磷之间的相关性。结果表明,白洋淀各湖区柱状沉积物总磷（TP）的平均含量为531~1223mg.kg-1DW,无机磷（IP）是白洋淀沉积物中磷的主要成分,占TP的72~83。湖区水体的污染及富营养化程度影响着生物可利用的铁/铝结合态磷（Fe/Al-P）在白洋淀不同湖区沉积物中的分布,从各形态磷含量和百分含量的变化幅度来看,均是Fe/Al-P〉有机磷（OP）〉钙结合态磷（Ca-P）。在垂向分布和两种粒级沉积物颗粒上,白洋淀沉积物各形态磷都有一定的变化规律,但不同磷形态的变化趋势不同,差异性也不一致。各形态磷相关性分析表明,在平均含量、垂向及粒级分布上,IP和Ca-P之间呈较好相关性,说明稳定的Ca-P是IP的主体;而在平均含量和垂向分布上,TP与IP和Ca-P之间都存在着较好的相关性,说明沉积物中TP的含量主要来自IP中的Ca-P。研究结果对于探讨白洋淀水污染沉积历史及内源磷释放对水体富营养化的贡献具有重要意义。

Distribution and vertical variation of phosphorus（P） forms on sand and silt/clay particles in the sediment cores from six representative sites of Baiyangdian Lake were studied,using the standard measurement and test（SMT） procedure of P forms for the freshwater sediments.Correlation coefficients among sediment P forms were also analyzed.Results showed that the average total P（TP） content in sediment cores varied from 531～1 223 mg·kg-1 DW.The inorganic P（IP） was the major P form in sediment cores and mostly accounted for 72%～83% of TP.The content of bioavailable P bounded to iron and aluminum oxide and hydroxide（Fe/Al-P） was greatly affected by the water quality of the sampling sites.In terms of the variation range of P forms content and percent content,Fe/Al-Porganic P（OP）P bounded to calcium（Ca-P）.The vertical variation of P forms and distribution on sand and silt/clay particles in the sediment cores varied in different sampling sites.IP had significant positive correlation with Ca-P,indicating that the increase of IP content was mainly due to non-available Ca-P.TP had significant positive correlations with IP and Ca-P respectively in space distribution and vertical variation,showing that the increase of TP content in sediment cores was mainly due to Ca-P.The results is useful for researching water pollution history and contribution to water eutrophication from internal sediment P in Baiyangdian Lake.