巢湖城市内河沉积物不同形态磷空间分布特征

Phosphorus Forms and Vertical Distribution in Sediments of Urban Rivers in Chaohu City

对巢湖市城市内河的表层沉积物及柱状沉积物进行了采样,并采用修正后的标准测试程序(SMT)测定了其中的总磷(TP)、无机磷(IP)、有机磷(OP)、铁/铝磷(Fe/Al-P)和钙磷(Ca-P),分析了各形态磷之间以及与沉积物有机质之间的相关性.结果表明,表层沉积物TP的质量分数在832.09～2 572.41mg.kg-1之间,其中以Fe/Al-P为主,占总磷的比例为42.0%～62.3%.采样点各形态磷随深度的增加总体呈现先升高后下降的趋势,但不同采样点出现峰值的深度有所不同,这种空间分布特征能够较好反映周边环境现状和入河污染负荷的变化.不同深度沉积物中各形态磷之间存在极显著的相关性(概率水平P<0.01),各形态磷与有机质也存在极其显著的正相关.

Total phosphorus（TP）,inorganic-phosphorus（IP）,organic-phosphorus（OP）,Fe/Al-bound phosphorus（Fe/Al-P） and Ca-bound phosphorus（Ca-P） in surface sediments and sediment cores of urban rivers in Chaohu City of Anhui Province were measured based on the modified standard measurement and test（SMT） procedure of phosphorus forms in the freshwater sediments.The correlations between phosphorus forms and organic matter content were also analyzed.The results show that the TP content in surface sediments varies from 832.09 to 2 572.41 mg·kg-1.Fe/Al-P is the major phosphorus species,and accounts for 42.0%～62.3% of TP.With the increase of depth,the trends of all phosphorus forms first increase and then decrease,and different sampling sites have different peak depths,which can well indicate surrounding environment status and changes in pollution load into the river.For the sediments of different depths,there are significant（P0.01） positive correlations between all phosphorus forms,and the correlations between organic matter contents and different phosphorus forms are also significant.