[1] Tagliabue A, Bowie A R, Boyd P W, et al. The integral role of iron in ocean biogeochemistry [J]. Nature, 2017, 543(7643): 51-59. doi: 10.1038/nature21058
[2] Boyd P W, Ellwood M J. The biogeochemical cycle of iron in the ocean [J]. Nature Geoscience, 2010, 3(10): 675-682. doi: 10.1038/ngeo964
[3] Raven J A, Evans M C W, Korb R E. The role of trace metals in photosynthetic electron transport in O2-evolving organisms [J]. Photosynthesis Research, 1999, 60(2-3): 111-150.
[4] Liu X W, Millero F J. The solubility of iron in seawater [J]. Marine Chemistry, 2002, 77(1): 43-54. doi: 10.1016/S0304-4203(01)00074-3
[5] Moore J K, Braucher O. Sedimentary and mineral dust sources of dissolved iron to the world ocean [J]. Biogeosciences, 2008, 5(3): 631-656. doi: 10.5194/bg-5-631-2008
[6] Tagliabue A, Mtshali T, Aumont O, et al. A global compilation of dissolved iron measurements: focus on distributions and processes in the Southern Ocean [J]. Biogeosciences, 2012, 9(6): 2333-2349. doi: 10.5194/bg-9-2333-2012
[7] Martin J H, Fitzwater S E. Iron deficiency limits phytoplankton growth in the north-east Pacific subarctic [J]. Nature, 1988, 331(6154): 341-343. doi: 10.1038/331341a0
[8] Martin J H, Fitzwater S E, Gordon R M. Iron deficiency limits phytoplankton growth in Antarctic waters [J]. Global Biogeochemical Cycles, 1990, 4(1): 5-12. doi: 10.1029/GB004i001p00005
[9] Martin J H, Fitzwater S E, Gordon R M. We still say iron deficiency limits phytoplankton growth in the Subarctic Pacific [J]. Journal of Geophysical Research: Oceans, 1991, 96(C11): 20699-20700. doi: 10.1029/91JC01935
[10] De Baar H J W, Boyd P W, Coale K H, et al. Synthesis of iron fertilization experiments: From the iron age in the age of enlightenment [J]. Journal of Geophysical Research: Oceans, 2005, 110(C9): C09S16.
[11] Boyd P W, Jickells T, Law C S, et al. Mesoscale iron enrichment experiments 1993-2005: synthesis and future directions [J]. Science, 2007, 315(5812): 612-617. doi: 10.1126/science.1131669
[12] Martin J H. Glacial-interglacial CO2 change: the iron hypothesis [J]. Paleoceanography and Paleoclimatology, 1990, 5(1): 1-13.
[13] Watson A J, Bakker D C E, Ridgwell A J, et al. Effect of iron supply on Southern Ocean CO2 uptake and implications for glacial atmospheric CO2 [J]. Nature, 2000, 407(6805): 730-733. doi: 10.1038/35037561
[14] Ingall E D, Bustin R M, Van Cappellen P. Influence of water column anoxia on the burial and preservation of carbon and phosphorus in marine shales [J]. Geochimica et Cosmochimica Acta, 1993, 57(2): 303-316. doi: 10.1016/0016-7037(93)90433-W
[15] Van Cappellen P, Ingall E D. Redox stabilization of the atmosphere and oceans by phosphorus-limited marine productivity [J]. Science, 1996, 271(5248): 493-496. doi: 10.1126/science.271.5248.493
[16] Dale A W, Nickelsen L, Scholz F, et al. A revised global estimate of dissolved iron fluxes from marine sediments [J]. Global Biogeochemical Cycles, 2015, 29(5): 691-707. doi: 10.1002/2014GB005017
[17] Elrod V A, Berelson W M, Coale K H, et al. The flux of iron from continental shelf sediments: a missing source for global budgets [J]. Geophysical Research Letters, 2004, 31(12): L12307.
[18] Severmann S, McManus J, Berelson W M, et al. The continental shelf benthic iron flux and its isotope composition [J]. Geochimica et Cosmochimica Acta, 2010, 74(14): 3984-4004. doi: 10.1016/j.gca.2010.04.022
[19] Shi X M, Wei L, Hong Q Q, et al. Large benthic fluxes of dissolved iron in China coastal seas revealed by 224Ra/228Th disequilibria [J]. Geochimica et Cosmochimica Acta, 2019, 260: 49-61. doi: 10.1016/j.gca.2019.06.026
[20] Fung I Y, Meyn S K, Tegen I, et al. Iron supply and demand in the upper ocean [J]. Global Biogeochemical Cycles, 2000, 14(1): 281-295. doi: 10.1029/1999GB900059
[21] Jickells T D, An Z S, Andersen K K, et al. Global iron connections between desert dust, ocean biogeochemistry, and climate [J]. Science, 2005, 308(5718): 67-71. doi: 10.1126/science.1105959
[22] Sarthou G, Baker A R, Blain S, et al. Atmospheric iron deposition and sea-surface dissolved iron concentrations in the eastern Atlantic Ocean [J]. Deep Sea Research Part I: Oceanographic Research Papers, 2003, 50(10-11): 1339-1352. doi: 10.1016/S0967-0637(03)00126-2
[23] Mahowald N M, Baker A R, Bergametti G, et al. Atmospheric global dust cycle and iron inputs to the ocean [J]. Global Biogeochemical Cycles, 2005, 19(4): GB4025.
[24] Yücel M, Gartman A, Chan C S, et al. Hydrothermal vents as a kinetically stable source of iron-sulphide-bearing nanoparticles to the ocean [J]. Nature Geoscience, 2011, 4(6): 367-371. doi: 10.1038/ngeo1148
[25] Fitzsimmons J N, Boyle E A, Jenkins W J. Distal transport of dissolved hydrothermal iron in the deep South Pacific Ocean [J]. Proceedings of the National Academy of Sciences of the United States of America, 2014, 111(47): 16654-16661. doi: 10.1073/pnas.1418778111
[26] Bennett S A, Rouxel O, Schmidt K, et al. Iron isotope fractionation in a buoyant hydrothermal plume, 5°S Mid-Atlantic Ridge [J]. Geochimica et Cosmochimica Acta, 2009, 73(19): 5619-5634. doi: 10.1016/j.gca.2009.06.027
[27] Wu J F, Wells M L, Rember R. Dissolved iron anomaly in the deep tropical-subtropical Pacific: evidence for long-range transport of hydrothermal iron [J]. Geochimica et Cosmochimica Acta, 2011, 75(2): 460-468. doi: 10.1016/j.gca.2010.10.024
[28] Resing J A, Sedwick P N, German C R, et al. Basin-scale transport of hydrothermal dissolved metals across the South Pacific Ocean [J]. Nature, 2015, 523(7559): 200-203. doi: 10.1038/nature14577
[29] Saito M A, Noble A E, Tagliabue A, et al. Slow-spreading submarine ridges in the South Atlantic as a significant oceanic iron source [J]. Nature Geoscience, 2013, 6(9): 775-779. doi: 10.1038/ngeo1893
[30] Tagliabue A, Bopp L, Dutay J C, et al. Hydrothermal contribution to the oceanic dissolved iron inventory [J]. Nature Geoscience, 2010, 3(4): 252-256. doi: 10.1038/ngeo818
[31] Luo C, Mahowald N, Bond T, et al. Combustion iron distribution and deposition [J]. Global Biogeochemical Cycles, 2008, 22(1): GB1012.
[32] Conway T M, Hamilton D S, Shelley R U, et al. Tracing and constraining anthropogenic aerosol iron fluxes to the North Atlantic Ocean using iron isotopes [J]. Nature Communications, 2019, 10(1): 2628. doi: 10.1038/s41467-019-10457-w
[33] Johnson K S, Chavez F P, Friederich G E. Continental-shelf sediment as a primary source of iron for coastal phytoplankton [J]. Nature, 1999, 398(6729): 697-700. doi: 10.1038/19511
[34] Gledhill M, Buck K N. The organic complexation of iron in the marine environment: a review [J]. Frontiers in Microbiology, 2012, 3: 69.
[35] Von Der Heyden B P, Roychoudhury A N. A review of colloidal iron partitioning and distribution in the open ocean [J]. Marine Chemistry, 2015, 177: 9-19. doi: 10.1016/j.marchem.2015.05.010
[36] Tagliabue A, Aumont O, DeAth R, et al. How well do global ocean biogeochemistry models simulate dissolved iron distributions? [J]. Global Biogeochemical Cycles, 2016, 30(2): 149-174. doi: 10.1002/2015GB005289
[37] Fitzsimmons J N, Carrasco G G, Wu J F, et al. Partitioning of dissolved iron and iron isotopes into soluble and colloidal phases along the GA03 GEOTRACES North Atlantic Transect [J]. Deep Sea Research Part II: Topical Studies in Oceanography, 2015, 116: 130-151. doi: 10.1016/j.dsr2.2014.11.014
[38] Cullen J T, Bergquist B A, Moffett J W. Thermodynamic characterization of the partitioning of iron between soluble and colloidal species in the Atlantic Ocean [J]. Marine Chemistry, 2006, 98(2-4): 295-303. doi: 10.1016/j.marchem.2005.10.007
[39] Fitzsimmons J N, John S G, Marsay C M, et al. Iron persistence in a distal hydrothermal plume supported by dissolved-particulate exchange [J]. Nature Geoscience, 2017, 10(3): 195-201. doi: 10.1038/ngeo2900
[40] Buck K N, Sedwick P N, Sohst B, et al. Organic complexation of iron in the eastern tropical South Pacific: results from US GEOTRACES Eastern Pacific Zonal Transect (GEOTRACES cruise GP16) [J]. Marine Chemistry, 2018, 201: 229-241. doi: 10.1016/j.marchem.2017.11.007
[41] Rue E L, Bruland K W. The role of organic complexation on ambient iron chemistry in the equatorial Pacific Ocean and the response of a mesoscale iron addition experiment [J]. Limnology and Oceanography, 1997, 42(5): 901-910. doi: 10.4319/lo.1997.42.5.0901
[42] Völker C, Tagliabue A. Modeling organic iron-binding ligands in a three-dimensional biogeochemical ocean model [J]. Marine Chemistry, 2015, 173: 67-77. doi: 10.1016/j.marchem.2014.11.008
[43] Johnson M S, Meskhidze N. Atmospheric dissolved iron deposition to the global oceans: effects of oxalate-promoted Fe dissolution, photochemical redox cycling, and dust mineralogy [J]. Geoscientific Model Development, 2013, 6(4): 1137-1155. doi: 10.5194/gmd-6-1137-2013
[44] Schroth A W, Crusius J, Sholkovitz E R, et al. Iron solubility driven by speciation in dust sources to the ocean [J]. Nature Geoscience, 2009, 2(5): 337-340. doi: 10.1038/ngeo501
[45] Winckler G, Anderson R F, Jaccard S L, et al. Ocean dynamics, not dust, have controlled equatorial Pacific productivity over the past 500 000 years [J]. Proceedings of the National Academy of Sciences of the United States of America, 2016, 113(22): 6119-6124. doi: 10.1073/pnas.1600616113
[46] Tagliabue A, Sallee J B, Bowie A R, et al. Surface-water iron supplies in the Southern Ocean sustained by deep winter mixing [J]. Nature Geoscience, 2014, 7(4): 314-320. doi: 10.1038/ngeo2101
[47] Buck K N, Bruland K W. The physicochemical speciation of dissolved iron in the Bering Sea, Alaska [J]. Limnology and Oceanography, 2007, 52(5): 1800-1808. doi: 10.4319/lo.2007.52.5.1800
[48] Shaw T J, Gieskes J M, Jahnke R A. Early diagenesis in differing depositional environments: the response of transition metals in pore water [J]. Geochimica et Cosmochimica Acta, 1990, 54(5): 1233-1246. doi: 10.1016/0016-7037(90)90149-F
[49] Noffke A, Hensen C, Sommer S, et al. Benthic iron and phosphorus fluxes across the Peruvian oxygen minimum zone [J]. Limnology and Oceanography, 2012, 57(3): 851-867. doi: 10.4319/lo.2012.57.3.0851
[50] Cai P H, Shi X M, Moore W S, et al. 224Ra: 228Th disequilibrium in coastal sediments: implications for solute transfer across the sediment-water interface [J]. Geochimica et Cosmochimica Acta, 2014, 125: 68-84. doi: 10.1016/j.gca.2013.09.029
[51] Cai P H, Shi X M, Hong Q Q, et al. Using 224Ra: 228Th disequilibrium to quantify benthic fluxes of dissolved inorganic carbon and nutrients into the Pearl River Estuary [J]. Geochimica et Cosmochimica Acta, 2015, 170: 188-203. doi: 10.1016/j.gca.2015.08.015
[52] Schlitzer R, Anderson R F, Dodas E M, et al. The GEOTRACES intermediate data product 2017 [J]. Chemical Geology, 2018, 493: 210-223. doi: 10.1016/j.chemgeo.2018.05.040
[53] Raiswell R, Tranter M, Benning L G, et al. Contributions from glacially derived sediment to the global iron (oxyhydr)oxide cycle: implications for iron delivery to the oceans [J]. Geochimica et Cosmochimica Acta, 2006, 70(11): 2765-2780. doi: 10.1016/j.gca.2005.12.027
[54] Smith Jr K L, Robison B H, Helly J J, et al. Free-drifting icebergs: hot spots of chemical and biological enrichment in the Weddell Sea [J]. Science, 2007, 317(5837): 478-482. doi: 10.1126/science.1142834
[55] Zhang R F, John S G, Zhang J, et al. Transport and reaction of iron and iron stable isotopes in glacial meltwaters on Svalbard near Kongsfjorden: from rivers to estuary to ocean [J]. Earth and Planetary Science Letters, 2015, 424: 201-211. doi: 10.1016/j.jpgl.2015.05.031
[56] Von Damm K L, Edmond J M, Grant B, et al. Chemistry of submarine hydrothermal solutions at 21 °N, East Pacific Rise [J]. Geochimica et Cosmochimica Acta, 1985, 49(11): 2197-2220. doi: 10.1016/0016-7037(85)90222-4
[57] Douville E, Charlou J L, Oelkers E H, et al. The rainbow vent fluids (36°14′N, MAR): the influence of ultramafic rocks and phase separation on trace metal content in Mid-Atlantic Ridge hydrothermal fluids [J]. Chemical Geology, 2002, 184(1-2): 37-48. doi: 10.1016/S0009-2541(01)00351-5
[58] Statham P J, German C R, Connelly D P. Iron (II) distribution and oxidation kinetics in hydrothermal plumes at the Kairei and Edmond vent sites, Indian Ocean [J]. Earth and Planetary Science Letters, 2005, 236(3-4): 588-596. doi: 10.1016/j.jpgl.2005.03.008
[59] Rudnicki M D, Elderfield H. A chemical model of the buoyant and neutrally buoyant plume above the TAG vent field, 26 degrees N, Mid-Atlantic Ridge [J]. Geochimica et Cosmochimica Acta, 1993, 57(13): 2939-2957. doi: 10.1016/0016-7037(93)90285-5
[60] Li M, Toner B M, Baker B J, et al. Microbial iron uptake as a mechanism for dispersing iron from deep-sea hydrothermal vents [J]. Nature Communications, 2014, 5: 3192. doi: 10.1038/ncomms4192
[61] Toner B M, Fakra S C, Manganini S J, et al. Preservation of iron(II) by carbon-rich matrices in a hydrothermal plume [J]. Nature Geoscience, 2009, 2(3): 197-201. doi: 10.1038/ngeo433
[62] 王建强, 李小虎, 毕冬伟, 等. 全球海水剖面Fe同位素组成的不均一性及其影响因素[J]. 地球科学, 2017, 42(9):1519-1530. [WANG Jianqiang, LI Xiaohu, BI Dongwei, et al. Fe isotopic composition heterogeneity of seawater profiles and its influence factors [J]. Earth Science, 2017, 42(9): 1519-1530.
[63] Brantley S L, Liermann L J, Guynn R L, et al. Fe isotopic fractionation during mineral dissolution with and without bacteria [J]. Geochimica et Cosmochimica Acta, 2004, 68(15): 3189-3204. doi: 10.1016/j.gca.2004.01.023
[64] Wiederhold J G, Kraemer S M, Teutsch N, et al. Iron isotope fractionation during proton-promoted, ligand-controlled, and reductive dissolution of goethite [J]. Environmental Science & Technology, 2006, 40(12): 3787-3793.
[65] Dideriksen K, Baker J A, Stipp S L S. Equilibrium Fe isotope fractionation between inorganic aqueous Fe(III) and the siderophore complex, Fe(III)-desferrioxamine B [J]. Earth and Planetary Science Letters, 2008, 269(1-2): 280-290. doi: 10.1016/j.jpgl.2008.02.022
[66] Conway T M, John S G. Quantification of dissolved iron sources to the North Atlantic Ocean [J]. Nature, 2014, 511(7508): 212-215. doi: 10.1038/nature13482
[67] Fantle M S, DePaolo D J. Iron isotopic fractionation during continental weathering [J]. Earth and Planetary Science Letters, 2004, 228(3-4): 547-562. doi: 10.1016/j.jpgl.2004.10.013
[68] John S G, Helgoe J, Townsend E, et al. Biogeochemical cycling of Fe and Fe stable isotopes in the Eastern Tropical South Pacific [J]. Marine Chemistry, 2018, 201: 66-76. doi: 10.1016/j.marchem.2017.06.003
[69] Henkel S, Kasten S, Hartmann J F, et al. Iron cycling and stable Fe isotope fractionation in Antarctic shelf sediments, King George Island [J]. Geochimica et Cosmochimica Acta, 2018, 237: 320-338. doi: 10.1016/j.gca.2018.06.042
[70] Staubwasser M, Von Blanckenburg F, Schoenberg R. Iron isotopes in the early marine diagenetic iron cycle [J]. Geology, 2006, 34(8): 629-632. doi: 10.1130/G22647.1
[71] Homoky W B, John S G, Conway T M, et al. Distinct iron isotopic signatures and supply from marine sediment dissolution [J]. Nature Communications, 2013, 4: 2143. doi: 10.1038/ncomms3143
[72] Radic A, Lacan F, Murray J W. Iron isotopes in the seawater of the equatorial Pacific Ocean: new constraints for the oceanic iron cycle [J]. Earth and Planetary Science Letters, 2011, 306(1-2): 1-10. doi: 10.1016/j.jpgl.2011.03.015
[73] Lough A J M, Klar J K, Homoky W B, et al. Opposing authigenic controls on the isotopic signature of dissolved iron in hydrothermal plumes [J]. Geochimica et Cosmochimica Acta, 2017, 202: 1-20. doi: 10.1016/j.gca.2016.12.022
[74] Nasemann P, Gault-Ringold M, Stirling C H, et al. Processes affecting the isotopic composition of dissolved iron in hydrothermal plumes: a case study from the Vanuatu back-arc [J]. Chemical Geology, 2018, 476: 70-84. doi: 10.1016/j.chemgeo.2017.11.005
[75] Rouxel O, Toner B M, Manganini S J, et al. Geochemistry and iron isotope systematics of hydrothermal plume fall-out at East Pacific Rise 9°50′N [J]. Chemical Geology, 2016, 441: 212-234. doi: 10.1016/j.chemgeo.2016.08.027
[76] Abadie C, Lacan F, Radic A, et al. Iron isotopes reveal distinct dissolved iron sources and pathways in the intermediate versus deep Southern Ocean [J]. Proceedings of the National Academy of Sciences of the United States of America, 2017, 114(5): 858-863. doi: 10.1073/pnas.1603107114
[77] John S G, Mendez J, Moffett J, et al. The flux of iron and iron isotopes from San Pedro Basin sediments [J]. Geochimica et Cosmochimica Acta, 2012, 93: 14-29. doi: 10.1016/j.gca.2012.06.003
[78] Wu J F, Boyle E, Sunda W, et al. Soluble and colloidal iron in the oligotrophic North Atlantic and North Pacific [J]. Science, 2001, 293(5531): 847-849. doi: 10.1126/science.1059251
[79] Marsay C M, Lam P J, Heller M I, et al. Distribution and isotopic signature of ligand-leachable particulate iron along the GEOTRACES GP16 East Pacific Zonal Transect [J]. Marine Chemistry, 2018, 201: 198-211. doi: 10.1016/j.marchem.2017.07.003
[80] Horner T J, Williams H M, Hein J R, et al. Persistence of deeply sourced iron in the Pacific Ocean [J]. Proceedings of the National Academy of Sciences of the United States of America, 2015, 112(5): 1292-1297. doi: 10.1073/pnas.1420188112
[81] Lund D C, Asimow P D, Farley K A, et al. Enhanced East Pacific Rise hydrothermal activity during the last two glacial terminations [J]. Science, 2016, 351(6272): 478-482. doi: 10.1126/science.aad4296
[82] Costa K M, McManus J F, Middleton J L, et al. Hydrothermal deposition on the Juan de Fuca Ridge over multiple glacial-interglacial cycles [J]. Earth and Planetary Science Letters, 2017, 479: 120-132. doi: 10.1016/j.jpgl.2017.09.006
[83] Hasenclever J, Knorr G, Rupke L H, et al. Sea level fall during glaciation stabilized atmospheric CO2 by enhanced volcanic degassing [J]. Nature Communications, 2017, 8: 15867. doi: 10.1038/ncomms15867
[84] Crowley J W, Katz R F, Huybers P, et al. Glacial cycles drive variations in the production of oceanic crust [J]. Science, 2015, 347(6227): 1237-1240. doi: 10.1126/science.1261508
[85] Lamy F, Gersonde R, Winckler G, et al. Increased dust deposition in the Pacific southern ocean during glacial periods [J]. Science, 2014, 343(6169): 403-407. doi: 10.1126/science.1245424
[86] Martínez-Garcia A, Rosell-Melé A, Jaccard S L, et al. Southern Ocean dust-climate coupling over the past four million years [J]. Nature, 2011, 476(7360): 312-315. doi: 10.1038/nature10310
[87] Murray R W, Leinen M, Knowlton C W. Links between iron input and opal deposition in the Pleistocene equatorial Pacific Ocean [J]. Nature Geoscience, 2012, 5(4): 270-274. doi: 10.1038/ngeo1422
[88] Loveley M R, Marcantonio F, Wisler M M, et al. Millennial-scale iron fertilization of the eastern equatorial Pacific over the past 100 000 years [J]. Nature Geoscience, 2017, 10(10): 760-764. doi: 10.1038/ngeo3024
[89] Costa K M, McManus J F, Anderson R F, et al. No iron fertilization in the equatorial Pacific Ocean during the last ice age [J]. Nature, 2016, 529(7587): 519-522. doi: 10.1038/nature16453
[90] Ardyna M, Lacour L, Sergi S, et al. Hydrothermal vents trigger massive phytoplankton blooms in the Southern Ocean [J]. Nature Communications, 2019, 10(1): 2451. doi: 10.1038/s41467-019-09973-6
[91] Scholz F, Severmann S, McManus J, et al. Beyond the Black Sea paradigm: the sedimentary fingerprint of an open-marine iron shuttle [J]. Geochimica et Cosmochimica Acta, 2014, 127: 368-380. doi: 10.1016/j.gca.2013.11.041
[92] Zhu X K, O'Nions R K, Guo Y L, et al. Secular variation of iron isotopes in North Atlantic Deep Water [J]. Science, 2000, 287(5460): 2000-2002. doi: 10.1126/science.287.5460.2000
[93] Chu N C, Johnson C M, Beard B L, et al. Evidence for hydrothermal venting in Fe isotope compositions of the deep Pacific Ocean through time [J]. Earth and Planetary Science Letters, 2006, 245(1-2): 202-217. doi: 10.1016/j.jpgl.2006.02.043
[94] Bereiter B, Eggleston S, Schmitt J, et al. Revision of the EPICA Dome C CO2 record from 800 to 600 kyr before present [J]. Geophysical Research Letters, 2015, 42(2): 542-549. doi: 10.1002/2014GL061957
[95] Lam P J, Bishop J K B. The continental margin is a key source of iron to the HNLC North Pacific Ocean [J]. Geophysical Research Letters, 2008, 35(7): L07608.
[96] Slemons L O, Murray J W, Resing J, et al. Western Pacific coastal sources of iron, manganese, and aluminum to the Equatorial Undercurrent [J]. Global Biogeochemical Cycles, 2010, 24(3): GB3024.
[97] Rose A L, Waite T D. Kinetics of hydrolysis and precipitation of ferric iron in seawater [J]. Environmental Science & Technology, 2003, 37(17): 3897-3903.
[98] Henkel S, Kasten S, Poulton S W, et al. Determination of the stable iron isotopic composition of sequentially leached iron phases in marine sediments [J]. Chemical Geology, 2016, 421: 93-102. doi: 10.1016/j.chemgeo.2015.12.003
[99] Revels B N, Zhang R F, Adkins J F, et al. Fractionation of iron isotopes during leaching of natural particles by acidic and circumneutral leaches and development of an optimal leach for marine particulate iron isotopes [J]. Geochimica et Cosmochimica Acta, 2015, 166: 92-104. doi: 10.1016/j.gca.2015.05.034