黄河中下游表层沉积物磷的赋存形态及生物有效性

Species and Bio-availability of Phosphorus in Surface Sediments from Middle and Lower Reaches of Yellow River

利用磷的连续分级提取方法,研究了黄河中下游16个沉积物样品中磷的赋存形态分布特征,并探讨了沉积物中磷的生物有效性。结果表明,黄河沉积物中总磷的含量为83.79～132.35μg·g-1,其中主要以无机磷的形式存在,而无机磷中以钙结合态磷为主。线性回归分析结果表明,NaOH-P的含量与活性态Fe、BD-P,NaOH-P含量的总和与活性态Fe、BD-P,NH4Cl-P含量的总和与活性态Fe、Al含量总和,均有一定的线性关系;沉积物中的总无机磷含量与沉积物的总有机质含量呈正相关关系。磷的生物有效性分析结果显示,潜在的生物有效性磷主要包括弱结合态磷、氧化还原敏感态磷、金属(水合)氧化物结合态磷3种赋存形态,黄河沉积物中潜在的生物有效性磷含量在9.02～37.20μg·g-1范围内,平均值为24.47μg·g-1,平均占沉积物总磷的22.43%、占总无机磷的35.59%。

Species and bio-availability in the sediments from middle and lower reaches of Yellow River were investigated using sequential extraction method. It was shown that total phosphorus in sediments varied from 83.79～132.35 μg·g^-1 and was mainly in the form of inorganic phosphorus dominated by HCl-P. The linear relationship between the NaOH-P and active Fe,the sum of BD-P and NaOH-P and active Fe,the sum of BD-P and NH4Cl-P and the sum of active Fe and Al was observed within the sixteen sediments. Also,the concentrations of IP were linearly correlated with the TOC. Moreover,the bio-available phosphorus （BAP） included NH4Cl-P,BD-P and NaOH-P and was ranging from 9.02 ～ 37.20 μg·g^-1,and average 24.47 μg·g^-1 for all sediment samples. The contribution of BAP to total （TP） and inorganic sedimentary phosphorus （IP） were 22.43% and 35.59% on average,respectively.