摘要
对水体沉积物中磷的环境地球化学研究中较普遍采用的7步法连续提取磷分级方案在实际应用中出现的一些问题进行了探讨。从该方法对水系沉积物成分分析标准物质GSD-12及太湖沉积物的分析结果看,该方法的应用中各形态的重现性问题必须得到重视,尤其是闭蓄态磷的提取中,实际操作中要尽量避免因沉积物固结容器底部而降低提取剂的提取效率,对于提取离心液过滤难的问题也一定要解决好。可交换态磷、铝磷和铁磷的提取液由于磷浓度低,可以不将其后的漂洗液混入后测定,以提高待测液中磷的浓度。另外,从GSD-12与太湖沉积物中磷形态特征的相似性看,GSD-12可以考虑作为淡水水体沉积物磷形态分级的标准物质,从而解决不同文献、不同研究项目在沉积物形态分析方面缺乏可比性的问题。
Application of seven- step sequential extraction protocol for fractionation of phosphorus in freshwater sediments was studied by phosphorus fractionation of water body sediment certified reference materials GSD- 12 and the sediment samples from Lake Taihu. The results showed that, reproducibility of fraction analysis is quite bad, especially the fraction of occluded P. The reason may be due to cementation of sediment when extracted P with sodium hydroxide and the incompleteness of the filtration of extraction. Therefore, efficiency of oscillation and filtration shall be improved. Fractions of exchangeable P and Al- P are so low that determination of P in the extraction was difficult. Therefore, it is suggested that not to amalgamate the extraction and wash solution before determination. Distribution of P fractions in GSD- 12 and that in Lake Taihu sediment are quite similar, so it is feasible to use GSD- 12 as the certified reference materials for fractionation of P in freshwater sediment.
出处
《农业环境科学学报》
CAS
CSCD
北大核心
2003年第3期349-352,共4页
Journal of Agro-Environment Science
基金
中科院知识创新重大项目(KZCX1-SW-12-Ⅱ-02)
国家自然科学基金项目(40071019)
中国博士后科学基金(2002031226)
关键词
沉积物
磷形态
化学连续提取法
应用
环境地球化学
sediment
phosphorus
geochemical fraction
chemical sequential extraction
certified reference materials
