收稿日期: 2009-06-02
修回日期: 2009-07-30
网络出版日期: 2011-10-10
基金资助
国家自然科学基金(40476035); 教育部留学回国基金(2004)
Vertical distributions of dissolved oxygen, manganese, and iron in the sediments from Vietnam upwelling zone of South China Sea
Received date: 2009-06-02
Revised date: 2009-07-30
Online published: 2011-10-10
Supported by
国家自然科学基金(40476035); 教育部留学回国基金(2004)
2007年夏季航次对南海越南上升流区的三个站位进行现场采样, 利用微电极技术测定了沉积物间隙水中的溶解氧(DO溶解氧分子)、锰(Mn2+)、铁(Fe2+)的浓度和氧化还原电位, 估算了DO的通量、消耗速率和有机碳的消耗速率。在沉积物间隙水中DO浓度随深度的增加而迅速降低, 渗透深度为9—48mm。在沉积物深处还检测到Mn2+ 和Fe2+。采用元素分析仪测定了沉积物中总有机碳(TOC)含量和总氮(TN)含量, 三个站位沉积物中的TOC含量为0.7%—1.03%, TN含量为0.052%—0.10%, C/N为10.5—16.0。从C/N可以看出, 该研究区域沉积物中的有机物有部分来源于陆源输入, 其中一个站位位于湄公河冲淡水区域, 其C/N最大。从氧化还原电位来看, 三个站位的沉积环境都属于还原性环境。此研究首次测量了南海越南上升流区沉积物的氧化还原化学成分, 对于认识该海区海底生物地球化学具有重要意义。
许昆明,邹文彬,司靖宇, . 南海越南上升流区沉积物中溶解氧、锰和铁的垂直分布特征[J]. 热带海洋学报, 2010 , 29(5) : 56 -64 . DOI: 10.11978/j.issn.1009-5470.2010.05.056
Sediments were sampled at three sites in the Vietnam upwelling zone of the South China Sea during a summer cruise in 2007. Microelectrodes were applied to measure the concentrations of dissolved oxygen molecules (DO), Mn2+, Fe2+, and redox potentials in the pore water of the sediments. The fluxes and consumption rates of DO and the consumption rates of total organic carbon (TOC) were estimated. It was found that DO concentration decreased with increasing depth in the sediments and that its penetration depths were between 9 to 48 mm. Mn2+ and Fe2+ were also detected in the sediments. TOC and total nitrogen (TN) were measured by an elemental analyzer. TOC values at the three sites were between 0.7%—1.03%, TN values were between 0.052%—0.10%, and C/N ratios were between 10.5—16.0. From the C/N ratios, it can be seen that the sediments in the region had terrestrial origins. The sampling site located at the freshwater plume of the Mekong River had maximum C/N ratios. The redox potentials indicated that all sediments belonged to reducing environments. This study measured the redox chemical species in sediments from the Vietnam upwelling zone of the South China Sea for the first time and provided vital clues to the biogeochemistry of the sediments in the region.
Key words： sediment; Fe; Mn; organic carbon; dissolved oxygen molecules
[1] 罗莎莎, 万国江. 云贵高原湖泊沉积物-水界面铁、锰、硫体系的研究进展[J]. 地质地球化学, 1999, 27(3): 47-52.
[2] Di TorO D M, Paquin P R, Subburamu K, et al. Sediment oxygen demand model: methane and ammonia oxidation[J]. Environmental Engineer, 1990, 116: 945-985.
[3] Nielsen L P, CHristensen P B, Revsbech N P, et al. Denitrification and oxygen respiration in biofilms studied with a microsensor for nitrous oxide and oxygen[J]. Microbial Ecology, 1990, 19: 63-72.
[4] 周伟华, 吴云华, 陈邵勇. 南沙群岛海域表层沉积物中有机物、铁和锰的分布特征[J].热带海洋学报, 2003, 22(1): 43-49.
[5] 许昆明, 司靖宇．适用于海洋沉积物间隙水中氧、锰(Ⅱ)、铁(Ⅱ)、硫分析的金汞齐微电极[J]．分析化学, 2007, 35(8): 1147-1150.
[6] 高学鲁, 陈绍勇, 马福俊,等. 南沙群岛西部海域两柱状沉积物中碳和氮的分布和来源特征及埋藏通量估算[J].热带海洋学报, 2008, 27(3): 38-44.
[7] 于雯泉, 钟少军. 海洋沉积物有机碳分析方法中干燥预处理过程人为误差的发现及其意义[J]. 环境科学学报, 2007, 27(5): 861-867.
[8] Stephan A, Ryba R M B. Effects of sample preparation on the measurement of organic carbon, hydrogen, nitrogen, sulfur and oxygen concentrations in marine sediments[J]. Chemosphere, 2002, 48: 139–147.
[9] Tung J W T, Tanner P A. Instrumental determination of organic carbon in marine sediments[J]. Marine Chemistry, 2003, 80 (2,3): 161–170 .
[10] King P, Kennedy K, Newton P P, et al. Analysis of total and organic carbon and total nitrogen in settling oceanic particles and a marine sediment: an interlaboratory comparison[J]. Marine Chemistry, 1998, 60 (3,4): 203–210.
[11] HEDGES J I. Carbon and nitrogen determinations of carbonate containing solids[J]. Limnological Oceanography, 1984, 29: 657-663.
[12] Iperen V J, Helder W A. Method for the determination of organic carbon in calcareous marine sediments[J]. Marine Geology, 1985, 64: 179-187.
[13] Froelich P N, Klinkhammer G P, Bender M L, et al. Early oxidation of organic matter in pelagic sediments of the eastern equatorial Atlantic: suboxic diagenesis[J]. Geochimica et Cosmochimica Acta, 1979, 43: 1075-1090.
[14]
[15] Cai W J, Zhao P, Theberge S M, et al. Porewater redox species, pH and pCO
[16] Cai W J, Sayles F L. Oxygen penetration depths and fluxes in marine sediments[J]. Marine Chemistry, 1996, 52: 123-131.
[17] Luther III G W, Reimers, C E, Nuzzio, D B, et al. In situ deployment of voltammetric, potentiometric and amperometric microelectrodes from a ROV to determine O2, Mn, Fe, S (-2) and pH in porewaters[J] . Environmental Science & Technology, 1999, 33: 4352–4356.
[18] Luther III, G W, Glazer, B T, et al. Use of voltammetric solid-state (micro) electrode for studying biogeochemical processer: Laboratory measurements to real time measurements with an in situ electrochemical analyzer(ISEA)[J]. Marine Chemistry, 2008, 108: 221–235.
[19] Boudreau, B P. A method-of-lines code for carbon and nutrient diagenesis in aquatic sediments[J]. Computers and Geosciences, 1996, 22: 479–496.
[20] Sauter E J, Schluter M, Suess E. Organic carbon flux and remineralization in surface sediments from the northern North Atlantic derived from porewater oxygen microprofiles[J]. Deep Sea Research, 2001, 48: 529–553.
[21] Meyers P A. Organic geochemical proxies of paleoceanographic, paleolimnologic, and paleoclimatic processe[J]. Organic Geochemistry, 1997, 27(5, 6): 213-250.
[22] Prahl F G, Ertel J R, Go(n)i M A, et al. Terrestrial organic carbon contributions to sediments on the Washington margin[J]. Geochimica et Cosmochimica Acta, 1994, 58(14): 3035-3048.
[23] Thornton S F, McManus J. Application of organic carbon and nitrogen stable isotope and C/N ratios as source indicators of organic matter provenance in estuarine systems: Evidence from the Tay Estuary, Scotland Estuarine[J]. Coastal and Shelf Science, 1994, 38: 219–233.
[24] Ruttenberg K C, Goni M A. Phosphorus distribution, C: N: P ratios, and δ13Corg in arctic, temperate and tropical coastal sediments: Tools for characterizing bulk sedimentary organic matter[J]. Marine Geology, 1997, 139: 123–145.
[25] Bordovskiy O K. Accumulation and transformation of organic substances in marine sediments[J]. Marine Geology, 1965, 3: 3–14.
[26] Prahl F G, Bennett J T, Carpenter R. The early diagenesis of aliphatic hydrocarbons and organic matter in sedimentary particulates from Dabob Bay[J]. Washington Geochimica et Cosmochimica Acta, 1980, 44: 1967–1976.
[27] Tang D L, Hiroshi K, Tran V D, et al. Offshore phytoplankton biomass increase and its oceanographic causes in the South China Sea[J]. 2004, 268: 31–41.
[28] 宋金明. 中国近海沉积物-海水界面化学[M]. 北京: 海洋出版社, 1997, 89-91.
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