我国不同营养状态湖泊沉积物有机磷形态分级特征研究

研究了我国不同区域的7个不同流域特征、生态结构、污染程度的湖泊表层沉积物中有机磷（P_o）形态的分布特征，分析了P_o各组分与沉积物其他组分的关系和生物有效性. 不同湖泊沉积物中P_o相对含量的差异表明其来源和生物地球化学循环的不同，不同湖泊沉积物中有机质（OM）与P_o表现出显著相关关系（R>²=0.80，p>＜0.01），除杞麓湖外，其它湖泊的OM与活性P_o、中活性P_o和非活性P_o也表现出显著相关关系（R>²分别为0.85、0.52、0.80，p>＜0.01）. 沉积物中有机磷中以中活性有机磷和非活性有机磷为主，其含量分别占总P_o的15.12%～66.73%和27.99%～77.72 %，活性P_o的平均相对含量为6.1%. 不同P_o组分的相对含量顺序为：residual P_o> HCl-P_o >fulvic acid-P_o>humic acid-P_o> NaHCO₃-P_o，平均的相对比例为8.3∶3.1∶2.2∶1.8∶1.0. 活性P_o和TP、P_i、P_o、NaHCO₃-P_i、NaOH-P_i呈显著正相关，非活性P_o与TP、P_o、NaOH-P_i呈显著相关，说明活性P_o很容易转化为生物可利用磷，同时非活性P_o也可能成为生物可利用磷的潜在源，非活性P_o只是化学溶解上的相对“惰性”，它仍具有潜在的生物活性.

Characteristics of Organic Phosphorus Fractions in Different Trophic Sediments of Lakes, China

In this study, the characteristics of organic phosphorus fractions in sediments of seven lakes with different drainage basin feature, ecological structure, and polluted levels from different regions were investigated, and the relationships between organic phosphorus (Po), inorganic phosphorus (Pi) and bioavailable characters were also discussed. The difference of the related content of Po in different sediments indicated the discrepancy of phosphorus sources and biogeochemical cycles in different lakes. Organic matter (OM) was significantly correlated with Po (R2 = 0.80, p < 0.01), and except for Lake Qilu, OM was significantly correlated with labile Po, moderately labile Po and nonlabile Po in all studied sediments (R2 were 0.85, 0.52, 0.80 respectively, p < 0.01). The moderately labile Po and nonlabile Po were the main fraction of Po in all studied lakes, and the relative contributions to total Po were 15.12%-66.73% and 27.99%-77.72%, respectively. The mean proportion of labile Po was 6.1% in studied sediments. The rank order of Po fractions was residual Po > HCl-Po > fulvic acid-Po > humic acid-Po > NaHCO3-Po with mean relative proportion 8.3:3.1:2.2:1.8:1.0. Labile Po was significantly correlated with total phosphorus (TP), Pi , Po, NaHCO3-Pi and NaOH-Pi . Furthermore, Labile Po was also significantly correlated with T), Po and NaOH-Pi in all studied sediments, which suggested that labile Po was transformed into bioavailable phosphorus and the nonlabile Po may become a potential source of available phosphorus, although it was considered as highly resistant fraction.