不同条件下乌梁素海污染物在冰-水体系中分布规律的模拟  

Pollutant distribution under different conditions in Lake Ulansuhai ice-water system

作　　者：吕宏洲 李畅游[1] 史小红[1] 赵胜男[1] 杨芳[1] 吴用[1] 宋爽[1] 

机构地区：[1]内蒙古农业大学水利与土木建筑工程学院,呼和浩特010018

出　　处：《湖泊科学》2015年第6期1151-1158,共8页Journal of Lake Sciences

基　　金：国家自然科学基金项目(51339002;51269016;51269017;51169017)资助

摘　　要：为探讨单一因素(如浓度、温度、酸碱度)对冰封期乌梁素海中营养盐和盐分(总氮、总磷、Na+和Cl-)迁移的影响,对不同条件下各物质水样进行室内单向结冰模拟,分析总结物质在冰层和冰下水层中的分布特征,并用分配系数(K)来表征.结果表明:冰体中物质浓度随水样初始浓度(C0)的增大而增大,随结冰温度的升高而减小;各物质在冰体中的浓度分布表现为顶层<中层<底层.总氮、总磷的分配系数K随C0的增大呈递减趋势,Na+和Cl-的K值随C0的增大呈递增趋势;对各条件下的K值进行假设检验,结果为:水样中物质初始浓度和结冰温度显著影响其在冰-水体系中的分布;同一温度下,C0较小时,酸碱度显著影响各物质在冰-水体系中的分布,C0较大时,酸碱度显著影响Na+和Cl-在冰-水体系中的分布,但对总氮、总磷浓度分布的影响不显著.可见,在不同环境因素下,各物质在冰-水体系中表现出不同的分布特征,对此进行模拟可为寒区湖泊污染物迁移和生物地球化学循环的研究提供一定的参考.Laboratory unidirectional freezing experiments were performed to investigate the migration of nutrients（ TN, TP） and sa- linity（ Na^＋ , Cl^- ） in Lake Ulansuhai water during ice season, and difference among single factors, including initial concentra- tion, freezing temperature and pH were tested. The distributions of TN, TP, Na ^＋ , Cl^ - in simulation ice cores were studied and partition coefficients between the ice and the unfrozen liquid were determined. The results showed that concentrations in ice in- creased with enhancing initial concentration and decreased with enhancing freezing temperature. The concentration in various seg- ments of the ice phase was in the order of： top 〈 middle 〈 bottom. The higher initial concentration, the lower partition coefficient K of TN and TP, but higher K of Na^＋ and Cl^-. At the significant level of 0.05, we found ： different initial concentration and freez- ing temperature can significant affect the distribution of TN, TP, Na^＋ and Cl^-. At different pH conditions, their distribution va- ries in lower initial concentration, but no significant change is found in higher initial concentration of TN and TP. Results indicated that transport processes of contaminants were greatly affected by its physical properties and the freezing environment factors.

关 键 词：单向结冰模拟 冰水双介质 物质迁移 分配系数 乌梁素海 

分 类 号：X524[环境科学与工程—环境工程]