Natural organic ligands controlling iron concentration in the water column in the North Pacific Ocean and important role of the organic ligands on the primary production.

天然有机配体控制北太平洋水体中铁浓度及其对初级生产的重要作用。

• 批准号: 12640475
• 负责人: KUMA Kenshi
• 金额: $ 2.18万
• 依托单位: HOKKAIDO UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2000
• 资助国家: 日本
• 起止时间: 2000 至 2001
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-12640475/
• 关键词: seawater; Fe(III) solubility; dissolved organic-Fe(III) complex; organic ligand; phytoplankton; primary production; 植物フランクトン; バクテリア

Vertical distributions of Fe(III) hydroxide solubilities and dissolved Fe concentrations, which are strongly related to the concentration and affinity of natural organic Fe(III) chelators in seawater, were measured at three typical stations (0-3500 m) and inside (HP) and outside (LP) a phytoplankton spring bloom patch area (0-250 m) in the northwestern North Pacific Ocean. Iron(III) hydroxide solubility in the surface mixed layer was generally high and variable, corresponding with the depth of high chlorophyll a concentrations. The high Fe(III) solubility in the surface layer was probably due to a high concentration or strong affinity of natural organic Fe(III) chelators, which were possibly released by phytoplankton or bacteria. In culture experiments, the dissolved siderophore-Fe(III) organic complex in seawater supplied biologically available inorganic Fe(III) species, which may determine the iron uptake rate in culture media by providing bioavailable Fe as the siderophore decomposes. The therma, photochemical and microbial decomposition of organic chelators complexed with Fe(III) in aquatic environments is probably one of the most important mechanisms for providing bioavailable inorganic Fe(III) species into thse environments. In middepth and deep waters, the Fe(III) solubility levels appeared to increase with increasing nutrient concentration. The increase in Fe(III) solubility with nutrient concentrations is likely related to the decomposition and transformation of sinking organic matter and is due to the formation of organic Fe(III) chelators through the decomposition of biogenic organic matter. The solubility profiles reveal that dissolved Fe concentrations in deep ocean waters are controlled primarily by the Fe(III) complexation with natural organic ligands.

在三个典型站（0-3500 m）和内部（HP ）和北太平洋西北部浮游植物春季绽放斑块区域（0-250 m）之外（LP）。氢氧化铁(III)在表面混合层中的溶解度一般较高且变化，与高叶绿素a浓度的深度相对应。表层中 Fe(III) 的高溶解度可能是由于天然有机 Fe(III) 螯合剂的高浓度或强亲和力，这些螯合剂可能是由浮游植物或细菌释放的。在培养实验中，海水中溶解的铁载体-Fe(III)有机复合物提供了生物可利用的无机Fe(III)物质，这可以通过在铁载体分解时提供生物可利用的Fe来确定培养基中的铁吸收率。在水生环境中与 Fe(III) 络合的有机螯合剂的热、光化学和微生物分解可能是将生物可利用的无机 Fe(III) 物种提供到这些环境中的最重要机制之一。在中深度和深水中，Fe(III) 溶解度水平似乎随着营养物浓度的增加而增加。 Fe(III) 溶解度随营养物浓度的增加可能与下沉有机物的分解和转化有关，并且是由于生物有机物分解形成有机 Fe(III) 螯合剂所致。溶解度曲线表明，深海水中溶解的 Fe 浓度主要由 Fe(III) 与天然有机配体的络合控制。

项目成果

S.Nakabayashi, K.Kuma, K.Sasaoka et al.: "Variation in iron(III) solubility and iron concentration in the northwestern North Pacific Ocean"Limnology and oceanography. (in press). (2002)

S.Nakabayashi、K.Kuma、K.Sasaoka 等：“北太平洋西北部铁(III) 溶解度和铁浓度的变化”湖沼学和海洋学。

S.Nakabayashi, M.Kusakabe K.Kuma, I.Kudo: "Vertical distributions of iron(III) hydroxide solubility and dissolved iron in the northwestern North Pacific Ocean"Geophysical Research Letters. 28(24). 4611-4614 (2001)

S.Nakabayashi，M.Kusakabe K.Kuma，I.Kudo：“北太平洋西北部氢氧化铁(III)溶解度和溶解铁的垂直分布”地球物理研究快报。

S. Nakabayashi, M. Kusakabe, K. Kuma, I. Kudo: "Vertical distributions of iron(III) hydroxide solubility and dissolved iron in the northwestern North Pacific Ocean"Geophysical Research Letters. 28(24). 4611-4614 (2001)

S. Nakabayashi、M. Kusakabe、K. Kuma、I. Kudo：“北太平洋西北部氢氧化铁（III）溶解度和溶解铁的垂直分布”地球物理研究快报。

S. Nakabayashi, K. Kuma, K. Sasaoka et al.: "Variation in iron(III) solubility and iron concentration in the northwestern North Pacific Ocean"Limnology and Oceanography. (in press). (2002)

S. Nakabayashi、K. Kuma、K. Sasaoka 等人：“北太平洋西北部铁(III) 溶解度和铁浓度的变化”湖沼学和海洋学。