【摘要】 研究了崇明东滩湿地低(S1)、中(S2)、高(S3)潮滩沉积物对磷的吸附特征。结果表明,沉积物吸磷过程主要发生在前24 h内,随后近于达到平衡状态。沉积物对PO43--P的平均吸附速率在0~0.5 h内最大,均超过了140 mg.kg-1.h-1;快速吸附过程主要发生在前11 h,前11 h的平均快速吸附速率表现为S1>S3>S2,且沉积物中细颗粒成分越多,沉积物对PO43--P的平均快速吸附速率越大。沉积物对磷的吸附等温线符合Langmuir吸附等温方程,根据Langmuir方程计算,沉积物对磷的吸附容量均>200 mg.kg-1,同时沉积物对PO43--P的吸附容量也表现为S1>S3>S2。原因可能同S1中细颗粒成分、有机碳和常量金属元素(Al、Ca、Fe、Mg)的百分含量较多而S2中细颗粒成分、有机碳和常量金属元素的百分含量较少有关。温度和pH值也影响沉积物对PO43--P的吸附作用。更多还原

【Abstract】 To better understand the phosphorus cycle in wetland,an experimental study was made on the phosphorus adsorption characteristics of sediments S₁,S₂ and S₃ sampled from the Congming Dongtan wetland at the Changjiang Estuary.The results showed that phosphorus adsorption process mainly happened within the first 24 h,and then arrived at a balance.The average quick adsorption rate increased with increasing percentages of fine fraction in the sediments,and the adsorption isotherm could be expressed by the Langmuir equation.According to the equation,the phosphorus adsorption capacity of the sediments was estimated to be more than 200 mg·kg^-1,and decreased in the sequence of S₁>S₃>S₂,which was possibly because of the higher percentages of fine fraction and the higher contents of TOC,Al,Fe,Ca and Mg in S₁ than in S₂.Soil temperature and pH also affected the phosphorus adsorption of sediments.更多还原