Iron and inorganic carbon in Liaodong Gulf sediments of Bohai Sea in China  

作　　者：NIU Lifeng LI Xuegang SONG Jinming YUAN Huamao LI Ning DAI Jicui 

机构地区：[1]Normal College, Qingdao University, Qingdao 266071, China [2]Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China

出　　处：《Acta Oceanologica Sinica》2006年第4期53-64,共12页海洋学报（英文版）

摘　　要：Iron in seawater is an essential trace metal for phytoplankton that plays an important role in the marine carbon cycle. But most studies focused on oceanic iron fertilization in high nutrient low chlorophyll （HNLC） seawaters. A study of inorganic carbon （IC） forms and its influencing factors was presented in Liaodong Gulf sediments, and especially the influence of iron was discussed in detail. Inorganic carbon in Liaodong Gulf sediments was divided into five forms： NaCl, NH3·H2O, NaOH, NH2OH·HCl and HCl. The concentration of NaCl and NaOH forms were similar and they only occupied the minority of total inorganic carbon （TIC）. However, NH3 ·H2O, NH2OH · HCl and HCl forms were the principal forms of TIC and accounted for more than 80% of TIC. Especially, the percentage of NH3·H2O form was much higher than that in the Changjiang River Estuary and Jiaozhou Bay sediments. All forms of inorganic carbon were influenced by organic carbon, pore water, iron, pH, redox potential （Eh） and sulfur potential（Es） in sediments, moreover, the influences had different characteristics for different IC forms. However, the redox reactions of iron affected mainly active IC forms. Iron had little effect on NH2OH· HCl and HCl forms of IC which were influenced mainly by pH. Iron had a stronger influence on NaCl, NaOH and NH3· H2O forms of IC ; the influence of Fe^2＋ was higher than Fe^3＋ and its effect on NH3 ·H2O form was stronger than on NaCl and NaOH forms.Iron in seawater is an essential trace metal for phytoplankton that plays an important role in the marine carbon cycle. But most studies focused on oceanic iron fertilization in high nutrient low chlorophyll （HNLC） seawaters. A study of inorganic carbon （IC） forms and its influencing factors was presented in Liaodong Gulf sediments, and especially the influence of iron was discussed in detail. Inorganic carbon in Liaodong Gulf sediments was divided into five forms： NaCl, NH3·H2O, NaOH, NH2OH·HCl and HCl. The concentration of NaCl and NaOH forms were similar and they only occupied the minority of total inorganic carbon （TIC）. However, NH3 ·H2O, NH2OH · HCl and HCl forms were the principal forms of TIC and accounted for more than 80% of TIC. Especially, the percentage of NH3·H2O form was much higher than that in the Changjiang River Estuary and Jiaozhou Bay sediments. All forms of inorganic carbon were influenced by organic carbon, pore water, iron, pH, redox potential （Eh） and sulfur potential（Es） in sediments, moreover, the influences had different characteristics for different IC forms. However, the redox reactions of iron affected mainly active IC forms. Iron had little effect on NH2OH· HCl and HCl forms of IC which were influenced mainly by pH. Iron had a stronger influence on NaCl, NaOH and NH3· H2O forms of IC ; the influence of Fe^2＋ was higher than Fe^3＋ and its effect on NH3 ·H2O form was stronger than on NaCl and NaOH forms.

关 键 词：different forms of inorganic carbon IRON Liaodong Gulf sediments 

分 类 号：P736.211[天文地球—海洋地质]