湖泊科学2019，Vol.31Issue(1)：81-87,7.DOI:10.18307/2019.0108
冰封期乌梁素海沉积物-水界面氨氮的交换特征
Exchange characteristics of ammonia nitrogen at the water and sediment interface during the ice-sealing period in Lake Ulansuhai
摘要
Abstract
Lake Ulansuhai is the largest lake in the Yellow River Basin with an area of 293 km2. The average air temperature is 7.3℃ and the winter is about six months with a cumulative negative accumulated temperature about 610-800℃·day. The lake water usually starts freezing in the early November and melting in the end of March or in the early April of the following year. The lake is completely sealed by ice in terms of ice-sealing period for about 100-130 days with an ice thickness of 0.63 m in average. To get better understanding in the migration mechanism of ammonia nitrogen at the water sediment interface and the impact of endogenous nutrients on the lake environment during the ice-sealing period, the water and sediment samples were collected at seven sampling sites in early February of 2018 in Lake Ulansuhai. The concentrations of ammonia nitrogen of the water samples were analyzed. The diffusion flux of ammonia nitrogen at the water sediment interface was estimated. The results showed that the concentrations of ammonia nitrogen in the water ranged from 0.55 mg/L to 1.60 mg/L with an average of 1.05 mg/L. The concentrations of ammonia nitrogen in the pore water of 0-5 cm surface sediments were one order of magnitude greater than that in overlying water which ranged from 6.64 mg/L to 18.63 mg/L with an average of 11.92 mg/L. The diffusion flux of ammonia from the sediments to the water was 1.282-4.269 mg/ (m2·d). This indicated that a large number of soluble pollutants had been transported to the sediments during the process of freezing. It would be the one of the dominated source of water pollution to the lake environment in the period of ice stability, during the period of ice thawing, and in a period of time after ice thawing.关键词
冰封期/乌梁素海/沉积物/氨氮/内源污染源Key words
Ice-sealing period/Lake Ulansuhai/sediment/ammonia nitrogen/endogenous pollution引用本文复制引用
姜涛,张生,赵胜男,史小红,孙标,田伟东,韩知明,吕杰..冰封期乌梁素海沉积物-水界面氨氮的交换特征[J].湖泊科学,2019,31(1):81-87,7.基金项目
国家自然科学基金项目(51569019,51509133,51669022,51339002) （51569019,51509133,51669022,51339002）
内蒙古自然科学基金项目(2016MS0406)联合资助 （2016MS0406）
