摘要
[目的]本文旨在探究不同浓度砷沉积物对磷的吸附差异。[方法]采用5和50 mg·L^(-1)砷溶液分别处理30和60 d,分别记为A_0(原土样)、A_(5-30)、A_(50-30)、A_(5-60)和A_(50-60)。以不同浓度砷处理沉积物为研究对象,通过添加0、1、5、10、20和40 mg·L^(-1)磷(K_2HPO_4,以P计)的室内模拟试验,探究磷在不同浓度砷沉积物上的吸附特征。[结果]不同浓度砷处理的沉积物中各种形态磷和砷的含量有不同程度变化,磷酸二钙(Ca_2-P)含量增加4.1～10.4 mg·L^(-1),磷酸八钙(Ca_8-P)含量增加6.6～14.4 mg·L^(-1),磷酸铝盐(Al-P)和磷酸铁盐(Fe-P)含量呈下降趋势,活性态砷(弱酸提取态砷、可还原态砷和可氧化态砷)占总砷的比例为2.52%～26.37%,残渣态砷占总砷的比例为71.14%～79.68%。随砷处理浓度增加,沉积物中非活性态磷向活性态磷转化,活性态砷向残渣态砷转化。沉积物对磷的吸附能力与沉积物中砷的浓度相关性较强,沉积物中砷浓度越高吸附磷的能力越差,沉积物对磷的截留能力减弱。随上覆水磷浓度的升高,不同处理沉积物砷的释放量均呈上升趋势。上覆水磷质量浓度为40 mg·L^(-1)时,沉积物砷的释放量为0.056 mg·L^(-1),超过地表水质量环境标准Ⅲ类水标准值。[结论]不同浓度砷处理能改变沉积物中砷和磷的总量及各形态的含量,活性态砷含量越高的沉积物对磷的吸附能力越强。
[Objectives]The purpose of this paper is to explore the difference of phosphorus adsorption characteristics of arsenic sediments with different concentrations.[Methods]The sediments were treated with arsenic at 5 and 50 mg·L^-1 of A 0(original sample),A 5-30,A 50-30,A 5-60 and A 50-60 for 30 and 60 days.The indoor simulation experiments were carried out by adding phosphorus(K 2HPO 4,P)at 0,1,5,10,20 and 40 mg·L^-1.Adsorption characteristics of phosphorus on arsenic sediments with different concentrations were explored.[Results]The increase of active phosphorus content in sediments treated with different concentrations was changed to varying degrees.Various forms of phosphorus and arsenic in sediments treated with different concentrations varied to different degrees.The content of form of arsenic and phosphorus varied to varying degrees in sediments treated with different arsenic concentrations.The content of dicalcium phosphate(Ca 2-P)increased by 4.1-10.4 mg·L^-1,the content of octacalcium phophate(Ca 8-P)increased by 6.6-14.4 mg·L^-1 and contents of aluminum phosphate(Al-P)and ferric phosphate(Fe-P)decreased.The proportion of active arsenic(including:weak acid extracted arsenic,reducible arsenic and oxidized arsenic)to total arsenic was 2.52%to 26.37%,and the proportion of residual arsenic to total arsenic was 71.14%to 79.68%.With the increase of arsenic concentration,inactive phosphorus transformed into active phosphorus,and active arsenic transformed into residual arsenic in sediments.The adsorption capacity of phosphorus on sediments was strongly correlated with the concentration of arsenic in sediments.The higher the concentration of arsenic was,the worse adsorption capacity of phosphorus,and the sediment retention capacity of sediments was weakened.With the increase in phosphorus concentration,the release of arsenic from sediments of different treatments showed an upward trend.When the concentration of phosphorus in overlying water was 40 mg·L^-1,arsenic released from sediments was 0.056 mg·L^-1,which exceeded the standard value of classⅢwater for surface water quality and environment.[Conclusions]Different concentrations of arsenic can change the total amount and speciation of arsenic and phosphorus in the sediment.The higher the content of active arsenic was,the stronger the adsorption capacity of phosphorus in the sediment.
作者
赵蓉
刘云根
王妍
赵立君
任伟
徐鸣洲
ZHAO Rong;LIU Yungen;WANG Yan;ZHAO Lijun;REN Wei;XU Mingzhou(College of Ecology and Soil & Water Conservation,Southwest Forestry University,Kunming 650224,China;Research Institute of Desertification,Southwest Forestry University,Kunming 650224,China;Wetland College,Southwest Forestry University,Kunming 650224,China)
出处
《南京农业大学学报》
CAS
CSCD
北大核心
2019年第3期576-581,共6页
Journal of Nanjing Agricultural University
基金
国家自然科学基金项目(3150147
31660139)
云南省高校土壤侵蚀与控制重点实验室资助项目
关键词
砷
沉积物
吸附
磷
湿地
arsenic
sediment
adsorption
phosphorus
wetland
