采用连续分级提取法巢湖沉积物中不同结合态氮的赋存特征5.13研讨.doc

采用连续分级提取法研究春季巢湖沉积物中不同结合态氮的赋存特征 钟立香1，王书航1，2，姜霞1,*，金相灿1 11.50%、9.76%、0.42%。酸解氨基酸态氮是可矿化态氮最有效贡献者,多元逐步回归方法得到“最优”方程为：y=0.696 AAN -108.918.连续提取法测得总氮值(TSEN)比用凯氏半微量法测得总氮值(TKN)偏小,但在误差允许的范围内, TSEN可替代半微量凯氏法测得的总氮.连续分级提取法研究沉积物中氮形态为湖泊水环境生态安全评估提供基础依据. 关键词：连续提取；氮形态；沉积物；巢湖 中图分类号： Study on Speciation Characteristics of Different Combined Nitrogen in the Sediments of Chaohu Lake by Sequential Extraction Methods ZHONG Li-xiang1, WANG Shu-hang1,2, JIANG Xia1, JIN Xiang-can1 (1: Chinese Research Academy of Environmental Sciences, Beijing, 100012, PR China; 2: Hefei University of Technology, School of Resource and Environment, Hefei, 230009, PR China) Abstract：The release capability and bioavailability of different nitrogen speciation in the surface sediment of Chaohu Lake were investigated. The nitrogen speciation were divided as the free nitrogen (FN), the exchangeable nitrogen (EN), the acid hydrolysable nitrogen (HN) and the residual nitrogen (RN) by sequential extraction methods. And their concentrations in the surface sediment were also analyzed. The results showed that the TKN concentrations of surface sediments ranged from 1 004 mg/kg～2 285 mg/kg, that the concentrations of nitrogen speciation followed the order of HN﹥EN﹥RN﹥FN, their proportion to the total extractable N were 78.32%, 11.50%, 9.76% and 0.42% respectively. AAN is the most efficient contributor to the mineral N with the best regression equation of y=0.696AAN-108.918 by multiple stepwise regression method. The total sediment extractable nitrogen (TSEN) was a little smaller than the total Kjeldhal nitrogen (TKN). However TSEN could take place of TKN within a certain confidence interval. Sequential extraction methods for nitrogen speciation in sediment provide basic data for the lake water environment ecological security assessment. Key words: Sequential extraction methods; Nitrogen speciation; Sediment; Chaohu Lake 1.引言（introduction） 氮作为水生生态系统新陈代谢作用中最关键的元素之一，是唯一不能由矿物质风化而得到的元素，其重要的生态学功能很早就被学术界所认识[1-3]。自从 HABER-BOS