青岛近海冬末春初海水碳酸盐体系的特征  

Characteristics of Carbonate System in the Coastal Sea Off Qingdao in Late Winter

作　　者：郝珍珍[1] 黄延吉 董春肖 李铁[1,2] 刘春颖[1,2] 姬泓巍[1] 祝陈坚[1] HAO Zhenzhen HUANG Yanji DONG Chunxiao LI Tie LIU Chunying JI Hongwei and ZHU Chenjian(College of Chemistry and Chemical Engineering, Ocean University of China Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Qingdao 266100)

机构地区：[1]中国海洋大学化学化工学院 [2]海洋化学理论与工程技术教育部重点实验室,山东青岛266100

出　　处：《海洋湖沼通报》2016年第4期29-37,共9页Transactions of Oceanology and Limnology

基　　金：中国海洋大学基本科研业务费项目(201262031);国家基础科学人才培养基金(J1103313)资助

摘　　要：通过在青岛近岸海域采集海水样品,测定了海水pH、总碱度（TA）、溶解无机碳（DIC）以及溶解钙离子,并根据这些参数计算了海水中的碳酸氢根、碳酸根等分量以及海水二氧化碳分压（pCO2）、碳酸钙饱和度等参数。各站点海水pH范围为8.09～8.18,平均8.13;TA范围为2309～2345（mol/kg,平均2325（mol/kg;DIC范围为2158～2200（mol/kg,平均2180（mol/kg;海水中溶解钙离子的浓度为0.3700～0.3732g/kg,平均0.3716g/kg。求得海水pCO2范围为371～476（atm,平均415（atm;方解石和文石的饱和度范围分别为2.31～2.84和1.45～1.78,平均值分别为2.57和1.61。通过与温度、盐度进行比较,发现冬末春初青岛近岸海域海水总碱度、溶解无机碳和溶解钙离子具有较为均匀的特征,是冬季混合导致的结果。海水pH有一定的变化性,与营养盐和叶绿素a的关系显示,观测区西部已开始增强的生物生产使海水pH升高,pH是该季节影响海水pCO2、碳酸钙饱和度等参数的主要因素。该季节青岛近海总体上表现为大气CO2的弱源,但西部海区是大气CO2的弱汇。Seawater samples were collected in the coastal sea off Qingdao in March 2014. Parameters of the carbonate system, i. e. , pH, total alkalinity （TA） and dissolved inorganic carbon （DIC）, as well as dissolved calcium ion （Ca2＋） in seawater were determined. The pH values ranged from 8.09 to 8. 18 with an average of 8.13 over the observed area. TA ranged from 2309 to 2345 with an average of 2325 （mol/kg. DIC was in a range between 2158 and 2200 and averaged 2180 （mol/kg. The dissolved calci- um ranged from 0. 3697 to 0. 3739 with an average value of 0. 3716 g/kg. Concentrations of bicarbonate and carbonate, partial pressure of carbon dioxide of seawater （pCO2） and saturation degrees of calcium carbonate were calculated based on the equilibriums of carbonate system. The pCO2 values ranged from 371 to 476 with an average of 415 （atm. The saturation degree of calcite ranged from 2.31 to 2.84 with an average of 2.57, and that of aragonite ranged from 1.45～1.78 with an average of 1.61. Comparing with the observed temperature and salinity data, it was suggested that TA, DIC and Ca2＋ were highly homogenized due to winter mixing in the coastal sea. The pH values of seawater showed slight but detectible variability from the east side to the west side of this area. The variations of pH with nutrients and chlorophyll a indicated that biological production increased in the western part of the observed area, which caused increase in pH of seawater, pH was the main factor influencing pCO2, and saturation degrees of calcium carbonate. It was suggested that the coastal sea off Qingdao was a weak source of atmospheric CO2 , generally.

关 键 词：碳酸盐体系 PH 总碱度 钙离子 青岛近海 

分 类 号：P734.2[天文地球—海洋化学]