Citation: | XU Piaopiao,SU Ni,LIAN Ergang,et al. Enrichment effect and environmental control of clay reactive iron in the Changjiang River estuary and East China Sea[J]. Marine Geology & Quaternary Geology,2024,44(4):54-64. DOI: 10.16562/j.cnki.0256-1492.2024030301 |
Chemical speciation analysis of iron (Fe) is a crucial method for understanding sediment provenance, environmental evolution, and the biogeochemical cycling of iron in various environments. However, there are limitations in studying iron speciation, especially in sediments in different grain sizes, which hinders the comprehensive understanding of the iron cycle. In this study, we focused on the surface sediments from the Changjiang River estuary to East China Sea shelf. We employed a six-step extraction method to obtain the concentrations of total Fe (FeT), highly reactive Fe (FeHR), poorly reactive Fe (FePR), and unreactive Fe (FeU) in both bulk sediment samples and their clay fractions. Results show an order of FeHR>FePR>FeU in abundance. FeT and FeHR contents in the bulk sample were closely related to the mean grain size and the concentrations of clay, TOC, and Al, indicating that clay minerals rich in organic matter are prone to enrich FeHR. The FeHR/FeT ratio in the clay fraction increased by 10% and the FePR/FeT ratio in the clay fraction decreased by 10% compared to the bulk sample, indicating an enrichment effect of FeHR on clay minerals. The dynamic estuarine environment controlled the distribution of Fe speciation in sediments, with higher FeT and FeHR contents observed in the bulk sediment samples from the turbidity maximum zone of the Changjiang River estuary, which significantly influenced by grain size. The clay fraction could effectively eliminate the influence of grain size, with FeT and FeHR being heavily retained in the low-salinity region at the forefront of the turbidity maximum zone, while in the medium to high-salinity offshore areas, the sources of Fe remained relatively stable, being mainly the mixture of FeHR-rich sediment from the Changjiang River and FeHR-poor sediment from the shelf. This study revealed that the migration of clay fractions from the watershed to the estuary and shelf might dominate the distribution and cycling of highly reactivity Fe at the land-sea interface, and provided important insights into the sources and sinks of particulate Fe in the ocean, geochemical cycling, and their environmental effects.
[1] |
Raiswell R, Canfield D E. Sources of iron for pyrite formation in marine sediments[J]. American Journal of Science, 1998, 298(3):219-245. doi: 10.2475/ajs.298.3.219
|
[2] |
Poulton S W, Raiswell R. The low-temperature geochemical cycle of iron: from continental fluxes to marine sediment deposition[J]. American Journal of Science, 2002, 302(9):774-805. doi: 10.2475/ajs.302.9.774
|
[3] |
Poulton S W, Raiswell R. Chemical and physical characteristics of iron oxides in riverine and glacial meltwater sediments[J]. Chemical Geology, 2005, 218(3-4):203-221. doi: 10.1016/j.chemgeo.2005.01.007
|
[4] |
Raiswell R. Iron Transport from the Continents to the Open Ocean: The Aging-Rejuvenation Cycle[J]. Elements, 2011, 7(2):101-106. doi: 10.2113/gselements.7.2.101
|
[5] |
Canfield D E. Reactive iron in marine sediments[J]. Geochimica et Cosmochimica Acta, 1989, 53:619-632. doi: 10.1016/0016-7037(89)90005-7
|
[6] |
Poulton S W, Canfield D E. Development of a sequential extraction procedure for iron: implications for iron partitioning in continentally derived particulates[J]. Chemical Geology, 2005, 214:209-221.
|
[7] |
Raiswell R. Towards a global highly reactive iron cycle[J]. Journal of Geochemical Exploration, 2006, 88(1-3):436-439. doi: 10.1016/j.gexplo.2005.08.098
|
[8] |
李超, 舒劲松, 许斐, 等. 沉积物中铁的化学相态分析进展[J]. 地球科学—中国地质大学学报, 2013, 38(3):454-460
LI Chao, SHU Jingsong, XU Fei, et al. The analytical development of low-temperature particulate Fe speciation[J]. Earth Science-Journal of China University of Geosciences, 2013, 38(3):454-460.]
|
[9] |
Wang D Y, Zhu M X, Sun C H, et al. Geochemistry of iron and sulfur in the Holocene marine sediments under contrasting depositional settings, with caveats for applications of paleoredox proxies[J]. Journal of Marine Systems, 2021, 220:103572. doi: 10.1016/j.jmarsys.2021.103572
|
[10] |
胡利民, 季钰涵, 赵彬, 等. 铁对海洋沉积有机碳保存的影响及其碳汇意义[J]. 中国科学: 地球科学, 2023, 53(9): 1967-1981
HU Limin, JI Yuhan, ZHAO Bin, et al. The effect of iron on the preservation of organic carbon in marine sediments and its implications for carbon sequestration[J]. SCIENCE CHINA: Earth Sciences, 2023, 66(9): 1946-1959.]
|
[11] |
Cornell R M, Schwertmann U. The Iron Oxides: Structure, Properties, Reactions, Occurrences and Uses[M]. John Wiley & Sons, 2003.
|
[12] |
Zhu M X, Hao X C, Shi X N, et al. Speciation and spatial distribution of solid-phase iron in surface sediments of the East China Sea continental shelf[J]. Applied Geochemistry, 2012, 27:892-905. doi: 10.1016/j.apgeochem.2012.01.004
|
[13] |
Li C, Yang S, Lian E, et al. Chemical speciation of iron in sediments from the Changjiang Estuary and East China Sea: Iron cycle and paleoenvironmental implications[J]. Quaternary International, 2017, 452:116-128. doi: 10.1016/j.quaint.2016.07.014
|
[14] |
Wei G Y, Chen T Y, Poulton S W, et al. A chemical weathering control on the delivery of particulate iron to the continental shelf[J]. Geochimica et Cosmochimica Acta, 2021, 308:204-216. doi: 10.1016/j.gca.2021.05.058
|
[15] |
恽才兴. 长江河口近期演变基本规律[M]. 北京: 海洋出版社, 2004, 8-14
YUN Caixing. Recent developments of the Changjiang Estuary[M]. Beijing: Ocean Press, 2004, 8-14.]
|
[16] |
郭磊城, 朱春燕, 何青, 等. 长江河口潮波时空特征再分析[J]. 海洋通报, 2017, 36(6):652-661
GUO Leicheng, ZHU Chunyan, HE Qing, et al. Examination of tidal wave properties in the Yangtze River estuary[J]. Marine Science Bulletin, 2017, 36(6):652-661.]
|
[17] |
苏纪兰, 袁立业. 中国近海水文[M]. 北京: 海洋出版社, 2005
SU Jilan, YUAN Liye. Hydrology of China Offshore Area[M]. Beijing: Ocean Press, 2005.]
|
[18] |
Liang Y H, Wang R, Sheng G D, et al. Geochemical controls on the distribution and bioavailability of heavy metals in sediments from Yangtze River to the East China Sea: Assessed by sequential extraction versus diffusive gradients in thin-films (DGT) technique[J]. Journal of Hazardous Materials, 2023, 452:131253. doi: 10.1016/j.jhazmat.2023.131253
|
[19] |
Mayer L M. Surface area control of organic carbon accumulation in continental shelf sediments[J]. Geochimica et Cosmochimica Acta, 1994a, 58:1271-1284.
|
[20] |
Mayer L M. Relationships between mineral surfaces and organic carbon concentrations in soils and sediments[J]. Chemical Geology, 1994b, 114:347-363.
|
[21] |
刘梦佳, 黄湘通, 连尔刚, 等. 长江口-东海内陆架悬浮重矿物组成与颗粒特征[J]. 古地理学报, 2024, 26(2):1-16
LIU Mengjia, HUANG Xiangtong, LIAN Ergang, et al. Composition and particle characteristics of heavy minerals in suspended solids from the Yangtze River estuary and East China Sea inner continental shelf[J]. Journal of Palaeogeography, 2024, 26(2):1-16.]
|
[22] |
Mao C P, Chen J, Yuan X Y, et al. Seasonal variation in the mineralogy of the suspended particulate matter of the lower Changjiang River at Nanjing, China[J]. Clays and Clay Minerals, 2010, 58(5):691-706. doi: 10.1346/CCMN.2010.0580508
|
[23] |
赵彬, 姚鹏, 于志刚. 有机碳—氧化铁结合对海洋环境中沉积有机碳保存的影响[J]. 地球科学进展, 2016, 31(11):1151-1158
ZHAO Bin, YAO Peng, YU Zhigang. The effect of organic carbon-iron oxide association on the preservation of sedimentary organic carbon in marine environments[J]. Advances in Earth Science, 2016, 31(11):1151-1158.]
|
[24] |
杨守业, 贾琦, 许心宁, 等. 海底反风化作用与关键元素循环[J]. 海洋地质与第四纪地质, 2023, 43(3):26-34
YANG Shouye, JIA Qi, XU Xinning, et al. Submarine reverse weathering and its effect on oceanic elements cycling[J]. Marine Geology & Quaternary Geology, 2023, 43(3):26-34.]
|
[25] |
Boyle E, Edmond J, Sholkovitz E. The mechanism of iron removal in estuaries[J]. Geochimica et Cosmochimica Acta, 1977, 41:1313-1324.
|
[26] |
Moore R M, Burton J D, Williams P J LeB, et al. The behaviour of dissolved organic material, iron and manganese in estuarine mixing[J]. Geochimica et Cosmochimica Acta, 1979, 43(6):919-926. doi: 10.1016/0016-7037(79)90229-1
|
[27] |
Mayer L M. Aggregation of colloidal iron during estuarine mixing: kinetics, mechanism, and seasonality[J]. Geochimica et Cosmochimica Acta, 1982, 46:2527-2535. doi: 10.1016/0016-7037(82)90375-1
|
[28] |
Figueres G, Martin J M, Meybeck M. Iron behaviour in the Zaire estuary[J]. Netherlands Journal of Sea Research, 1978, 12:329-337. doi: 10.1016/0077-7579(78)90035-2
|
[29] |
Zhang K D, Li A C, Huang P, et al. Sedimentary responses to the cross-shelf transport of terrigenous material on the East China Sea continental shelf[J]. Sedimentary Geology, 2019, 384:50-59. doi: 10.1016/j.sedgeo.2019.03.006
|
[30] |
Canfield D E, Lyons T W, Raiswell R. A model for iron deposition to euxinic Black Sea sediments[J]. American Journal of Science, 1996, 296:818-834. doi: 10.2475/ajs.296.7.818
|
[31] |
Poulton S W, Canfield D E. Ferruginous conditions: a dominant feature of the ocean through Earth's history[J]. Elements, 2011, 7:107-112. doi: 10.2113/gselements.7.2.107
|
[32] |
Clarkson M O, Poulton S W, Guilbaud R, et al. Assessing the utility of Fe/Al and Fe-speciation to record water column redox conditions in carbonate-rich sediments[J]. Chemical Geology, 2014, 382:111-122. doi: 10.1016/j.chemgeo.2014.05.031
|
[33] |
Cole D B, Zhang S, Planavsky N J. A new estimate of detrital redox-sensitive metal concentrations and variability in fluxes to marine sediments[J]. Geochimica et Cosmochimica Acta, 2017, 215:337-353. doi: 10.1016/j.gca.2017.08.004
|