德州引黄灌区主要河流沉积物各形态磷分布研究

Phosphorus Fractions in Sediments Along Three Major Rivers of Irrigation Districts of Yellow River in Dezhou City

对河流沉积物中各形态磷(P)的研究有助于认识沉积物中P的行为特征、水-沉积物界面上P的迁移、转化、可利用性以及水体营养状态。以德州引黄灌区为例,采用改进的RuttenbergSEDEX分级连续提取方法,分析了漳卫新河、马颊河和德惠新河表层沉积物中主要赋存形态磷的含量,以期为评价该地区水环境质量,探究水体污染来源以及制定相应的治理措施提供科学依据。结果表明,河流表层沉积物中总磷(TP)的含量为437.4～1197.0mg.kg-1,无机磷(IP)的含量为373.8～1136.4mg.kg-1,占TP的64.3%～98.5%。IP又分为弱吸附态磷(Lsor-P)、铁结合态磷(Fe-P)、自生磷和碎屑磷(Au-P&De-P),含量分别为26.4～415.2mg.kg-1、6.3～331.2mg.kg-1和302.3～563.6mg.kg-1,分别占TP的5.2%～54.3%、0.8%～31.5%、35.7%～80.9%。有机磷(OP)的含量为9.0～413.4mg.kg-1,占TP含量的1.55%～35.68%。三条河流沉积物中不同形态P含量的变化趋势不同,空间变异性大;从上游到下游,漳卫新河底泥中的TP呈下降趋势,马颊河底泥中TP变化幅度不大,德惠新河底泥中TP呈现出先增高后降低的趋势,变化幅度较大。相关分析表明黄河下游引黄灌区沉积物中部分形态P之间存在显著的相关性,表明这些形态的P可能来源相同或者在某些特定的条件下会相互转化。最后,提出了控制P排放来源、加强污水处理、提高农业P的利用效率以及加强相关的研究等建议。

Studies on phosphorus fractions in river sediments is helpful to recognize the behavioral character of P,to understand the migration,transformation,availability of P that on the water-sediment interface,and to master nutritional status of water bodies.As a case study in Dezhouirrigation distric（t115°45＇-117°36＇E,36°24＇-38°0＇N）of the Yellow River in China,the concentrations of phosphorus fractions in the sediments along Zhangweixin River,Majia River,and Dehuixin River were determined by the modified sequential extraction method（Ruttenberg SEDEX）.It is expected to provide a scientific basis for evaluating the water quality,exploring the phosphorus sources of water pollution,and finding appropriate management actionin this area.The results showed that the concentrations of total phosphorus（TP）,inorganic phosphorus（IP）,and organic phosphorus（OP）ranged from 437.4 to 1197.0 mg.kg-1,373.8 to 1136.4 mg.kg-1,and 9.0 to 413.4 mg.kg-1,respectively.Sediment samples were characterized by a dominance of the inorganic fraction（64.32%～98.53%）.For OP,however,it is 1.55%～ 35.68%.IP was also divided into three fractions：loosely adsorbed phosphorus（Lsor-P）,iron-bound phosphorus（Fe-P）,authigenic phosphorus and detritalphosphorus（Au-PDe-P）which were mainly associated Au-PDe-P（35.67%～80.89%）,Lsor-P and Fe-P accounted for5.21% ～54.27% and 0.77% ～31.54%,respectively.The distribution trends and large spatial variation of phosphorus fractions along three rivers were found.From up to down stream,the concentrations of TP in the Zhangweixin River,Majia River and Dehuixin River showed decreasing trend,smooth variation,and choppy change,respectively.The correlation between some kinds of phosphorus fractions along these rivers were significant,which suggested these fractions of phosphorus should derive from the same sources or transform into each other under certain conditions.Some advises,such as controlling phosphorus drainage sources,setting-up more sewage factories,improving the phosphorus use efficiency,and supporting more relative studies,were suggested.