海河干流柱芯不同粒径沉积物中有机质和磷形态分布研究

Organic Matter,Different Sized Phosphorus Fractions in the Core Sediments in the Mainstream of Haihe River,China

采用欧洲标准测试委员会制定的SMT法(标准测试方法)对海河干流不同粒径级柱芯沉积物中各种形态的磷进行分级提取和测定,并在此基础上讨论不同深度、不同粒径沉积物中磷形态分布特征。结果表明,在邢家圈和张家嘴两采样点,海河沉积物颗粒组成以细砂、极细砂为主,占总量的40%～60%。沉积物中总磷含量在560～1100μgP·g-1之间。在所有不同粒径沉积物中钙结合态磷(HCl-P)含量最高,占总磷的60%～80%,可交换态磷(Ex-P)含量极微,占总磷的2%～3%,不同粒径下各形态磷含量的高低顺序为:钙结合态磷(HCl-P)>有机磷(OP)>铁铝氧化物结合态磷(NaOH-P)>可交换态磷(Ex-P);张家嘴采样点表层沉积物中磷形态含量高于其他沉积深度磷含量,表明近年来,沉积的磷主要以人为输入为主;钙磷含量随粒径变化复杂,其他各形态磷的含量均随沉积物粒径变小而增高。此外,对各形态磷之间以及各形态磷与沉积物理化性质之间的相关性进行了讨论。

Sediments from Haihe mainstream were collected and examined on the basis of phosphorus（P） fractionation.SMT（standards,measurements and testing） procedure was adopted to investigate the changes in P concentration with depth in the core sediments.And on the basis of this discussion the distribution of P forms of the different depth and different size of sediment,the distribution characters of P forms in sediment cores were studied systematically.The results showed that fine sand and very fine sand were found to be the major grain size composition in sites Xingjiaquan and Zhangjiazui of the mainstream of the Haihe sediment,accounting for 40%～60% of the total particles composition.The contents of total P（TP） in the core sediments ranged from 560 to 1 100 μgP·g-1.The calcium bound P（HCl-P） showed considerable contribution to the sediment total P loads in the sediments with different particle sizes.Accounting for 60%～80% of TP,exchangeable P（ExP） existed in minor quantities,accounting for 2%～3% of TP.The results indicated that in both sites,the rank order of P fractions was HClPOrganic P（OP）NaOH-PEx-P in terms of their concentration.The P contents in the surface sediments of site Zhangjiazui were higher than those in other depth of core sediments.It suggested that most proportion of the phosphorus was from anthropogenic source.Except calcium bound P,the contents of all other P forms increased with sample particle size decreasing.The correlation coefficients between different P fractions and sediment geochemical characteristics were also discussed.