【摘要】 为了解苏州市水环境中营养元素的时空分布特征及潜在生态风险,于苏州市城区、城郊和郊区共设置16个采样点,并对全年水样和沉积物样进行各形态碳、氮、磷含量的测定。结果表明:(1)时间尺度上,水体中春季溶解性有机质(DOC)极显著低于秋、冬季,TN季节性差异不显著,春、夏季TP极显著高于秋、冬季。沉积物中总有机碳(TOC)、TN和TP均在冬季最高、春季最低。(2)空间尺度上,水体中城区TP高于城郊和郊区。沉积物中TOC、TP均呈现城区>郊区>城郊的分布特征。(3)水体富营养化评价综合指数表明,1个采样点为极富营养级,11个为重富营养级,4个为富营养级,春、夏两季富营养化风险高。(4)苏州市整体有机氮污染较严重,城区沉积物中生物有效性磷最高,对上覆水的磷释放风险最高。(5)相关性分析表明,沉积物中TP、无机磷和铁铝磷来源可能相同。更多还原

【Abstract】 In order to reveal space-time distribution characteristics and potential ecological risk of nutrients in aquatic environment in Suzhou city,16 sampling sites were set up in urban,suburb and rural area in Suzhou.Contents of C,N,P in different forms were determined during the year.The results showed that:(1)on the time scale,the contents of dissolved organic carbon(DOC)in spring were obviously lower than that of autumn and winter.There was no significant seasonal variation of TN.The contents of TP in spring and summer were significantly higher than that of autumn and winter.Total organic carbon(TOC),TN and TP in sediments were found to be the highest in winter and the lowest in spring.(2)On the spatial scale,TP in water samples presented the occurrence characteristics that urban area higher than rural area and suburb area.TOC and TP in sediment samples presented the occurrence characteristics that urban area>rural area>suburb area.(3)Comprehensive eutrophication index(EI)demonstrated that 1 sampling sites,11 sites and 4 sites were at the level of extreme eutrophication,severe eutrophication and eutrophication respectively.(4)The organic nitrogen pollution in Suzhou was severe generally.The content of bioavailable phosphorus in urban area was the highest,indicating that its ecological risk of phosphorus release was the highest in all regions.(5)Correlation analysis showed that TP,inorganic phosphorus and ferric/aluminous phosphorus in sediment samples might have the same source.更多还原