Preliminary study on source and sedimentary environment in the Mariana Trench

SONG Zijun; MENG Fanyi; LI Weiding; CHEN Linying; LUO Min

doi:10.16562/j.cnki.0256-1492.2022031801

2022 Vol. 42, No. 4

Article Contents

Article navigation > Marine Geology & Quaternary Geology > 2022 > 42(4): 84-95

Next Article Previous Article

SONG Zijun, MENG Fanyi, LI Weiding, CHEN Linying, LUO Min. Preliminary study on source and sedimentary environment in the Mariana Trench[J]. Marine Geology & Quaternary Geology, 2022, 42(4): 84-95. doi: 10.16562/j.cnki.0256-1492.2022031801

Citation:

SONG Zijun, MENG Fanyi, LI Weiding, CHEN Linying, LUO Min. Preliminary study on source and sedimentary environment in the Mariana Trench[J]. Marine Geology & Quaternary Geology, 2022, 42(4): 84-95. doi: 10.16562/j.cnki.0256-1492.2022031801

Preliminary study on source and sedimentary environment in the Mariana Trench

Shanghai Engineering Research Center of Hadal Science and Technology, College of Marine Sciences, Shanghai Ocean University, Shanghai 201306, China

More Information

Corresponding author: CHEN Linying, lychen@shou.edu.cn

Received Date: 18 March 2022

Revised Date: 11 May 2022

Publish Date: 28 August 2022

Abstract

Abstract

Hadal trenches (＞6000 m) represent the deepest parts on the Earth’s surface in unique topography and sedimentary processes, and are considered the final sink of sediments. The strontium (Sr) and neodymium (Nd) isotope compositions and clay-mineral assemblages of the detrital fraction of sediments in the southern Mariana Trench, as well as the concentrations of major and trace elements of bulk sediments at water depths of 5800～10954 m were analyzed to trace the sediment provenance and distinguish the changes in the sedimentary redox conditions. The whole Core MBR05 and the interval of 8～20 cm of Core MBR06 are dominated by valve fragments of the giant diatom Ethmodiscus rex, forming laminated diatom mats (LDMs). Both Sr-Nd isotope compositions and clay-mineral assemblages of the detrital fraction reflect a two-component mixing pattern consisting of Luzon Arc volcanic clastics and Asian aeolian dusts, showing greater aeolian dust contribution on the LDMs, indicating that the bloom of E. rex may be related to Asian aeolian dust input. Meanwhile, the rare earth elements (REEs) distribution pattern and weak or absent Ce anomalies in the LDM point to suboxic conditions during the LGM formation, while the non-LDM samples exhibit vey low to zero enrichment of redox-sensitive elements and negative Ce anomalies, indicating the deposition under oxic bottom-water conditions. It is inferred that changes in sedimentary environments is associated with the enhanced mineralization of organic matter caused by the rapid deposition of E. rex giant diatom. The bloom of E. rex giant diatom may be caused by the enhanced input of wind dust during the Last Glacial Maximum. This study is of relevance for understanding the heterogeneity of sediment composition in different water depths of hadal trench and its impact on the distribution, ecology, and activity intensity of benthic microorganisms in the trench areas.
- Sr-Nd isotope /
- clay minerals /
- LDM /
- sediment sources /
- sedimentary environment /
- Mariana Trench

FullText(HTML)

References

[1]	Wolff T. The concept of the hadal or ultra-abyssal fauna [J]. Deep Sea Research and Oceanographic Abstracts, 1970, 17(6): 983-1003. doi: 10.1016/0011-7471(70)90049-5 CrossRef Google Scholar
[2]	Jamieson A J, Fujii T, Mayor D J, et al. Hadal trenches: the ecology of the deepest places on Earth [J]. Trends in Ecology & Evolution, 2010, 25(3): 190-197. Google Scholar
[3]	Nakanishi M, Hashimoto J. A precise bathymetric map of the world's deepest seafloor, Challenger Deep in the Mariana Trench [J]. Marine Geophysical Research, 2011, 32(4): 455-463. doi: 10.1007/s11001-011-9134-0 CrossRef Google Scholar
[4]	Watling L, Guinotte J, Clark M R, et al. A proposed biogeography of the deep ocean floor [J]. Progress in Oceanography, 2013, 111: 91-112. doi: 10.1016/j.pocean.2012.11.003 CrossRef Google Scholar
[5]	林刚. 西太平洋新不列颠海沟沉积特征与源-汇过程及其时空变化[D]. 上海海洋大学硕士学位论文, 2019. Google Scholar LIN Gang. The characteristics and source-sink processes of sediments in the New Britain Trench of western Pacific Ocean and their temporal and spatial variations[D]. Master Dissertation of Shanghai Ocean University, 2019. Google Scholar
[6]	Nozaki Y, Ohta Y. Rapid and frequent turbidite accumulation in the bottom of Izu-Ogasawara Trench: Chemical and radiochemical evidence [J]. Earth and Planetary Science Letters, 1993, 120(3-4): 345-360. doi: 10.1016/0012-821X(93)90249-9 CrossRef Google Scholar
[7]	Danovaro R, Croce N D, Dell’Anno A D, et al. A depocenter of organic matter at 7800m depth in the SE Pacific Ocean [J]. Deep Sea Research Part I:Oceanographic Research Papers, 2003, 50(12): 1411-1420. doi: 10.1016/j.dsr.2003.07.001 CrossRef Google Scholar
[8]	Glud R N, Wenzhöfer F, Middelboe M, et al. High rates of microbial carbon turnover in sediments in the deepest oceanic trench on Earth [J]. Nature Geoscience, 2013, 6(4): 284-288. doi: 10.1038/ngeo1773 CrossRef Google Scholar
[9]	Oguri K, Kawamura K, Sakaguchi A, et al. Hadal disturbance in the Japan Trench induced by the 2011 Tohoku–Oki Earthquake [J]. Scientific Reports, 2013, 3: 1915. doi: 10.1038/srep01915 CrossRef Google Scholar
[10]	Ikehara K, Kanamatsu T, Nagahashi Y, et al. Documenting large earthquakes similar to the 2011 Tohoku-oki earthquake from sediments deposited in the Japan Trench over the past 1500 years [J]. Earth & Planetary Science Letters, 2016, 445: 48-56. Google Scholar
[11]	Howell D G, Murray R W. A budget for continental growth and denudation [J]. Science, 1986, 233(4762): 446-449. doi: 10.1126/science.233.4762.446 CrossRef Google Scholar
[12]	Hay W W, Wold C N. Relation of selected mineral deposits to the mass/age distribution of Phanerozoic sediments [J]. Geologische Rundschau, 1990, 79(2): 495-512. doi: 10.1007/BF01830641 CrossRef Google Scholar
[13]	Stewart H A, Jamieson A J. Habitat heterogeneity of hadal trenches: Considerations and implications for future studies [J]. Progress in Oceanography, 2018, 161: 47-65. doi: 10.1016/j.pocean.2018.01.007 CrossRef Google Scholar
[14]	Glud R N, Berg P, Thamdrup B, et al. Hadal trenches are dynamic hotspots for early diagenesis in the deep sea [J]. Communications Earth & Environment, 2021, 2(1): 21. Google Scholar
[15]	吕成功. 马里亚纳海槽两沉积岩芯主要化学元素的因子分析[J]. 黄渤海海洋, 1992, 10(1):34-41 Google Scholar LV Chenggong. Factor analysis of major chemical elements in the sediments of two cores from the Mariana trough [J]. Journal of Oceanography of Huanghai & Bohai Seas, 1992, 10(1): 34-41. Google Scholar
[16]	吕海滨, 王永吉. 马里亚纳海槽沉积物中的火山碎屑及火山灰特征[J]. 海洋通报, 1998, 17(2):58-64 Google Scholar LV Haibin, WANG Yongji. A preliminary study on features of volcanic debris and ash layers in the Mariana trough [J]. Marine Science Bulletin, 1998, 17(2): 58-64. Google Scholar
[17]	王汾连, 何高文, 王海峰, 等. 马里亚纳海沟柱状沉积物稀土地球化学特征及其指示意义[J]. 海洋地质与第四纪地质, 2016, 36(4):67-75 Google Scholar WANG Fenlian, HE Gaowen, WANG Haifeng, et al. Geochemistry of rare earth elements in a core from Mariana Trench and its significance [J]. Marine Geology & Quaternary Geology, 2016, 36(4): 67-75. Google Scholar
[18]	朱坤杰, 何树平, 陈芳, 等. 马里亚纳海沟南部海域沉积物的工程地质特性及其成因[J]. 地质学刊, 2015, 39(2):251-257 doi: 10.3969/j.issn.1674-3636.2015.02.251 CrossRef Google Scholar ZHU Kunjie, HE Shuping, CHEN Fang, et al. Engineering geological characteristics and genesis of the sediments from the southern Mariana Trench [J]. Journal of Geology, 2015, 39(2): 251-257. doi: 10.3969/j.issn.1674-3636.2015.02.251 CrossRef Google Scholar
[19]	张金鹏, 邓希光, 杨胜雄, 等. 马里亚纳海沟挑战者深渊南部7000 m水深处发现硅藻化石软泥[J]. 地质通报, 2015, 34(12):2352-2354 doi: 10.3969/j.issn.1671-2552.2015.12.021 CrossRef Google Scholar ZHANG Jinpeng, DENG Xigaung, YANG Shengxiong, et al. Diatom ooze found in 7000m submarine area of Challenger Depth in Mariana Trench [J]. Geological Bulletin of China, 2015, 34(12): 2352-2354. doi: 10.3969/j.issn.1671-2552.2015.12.021 CrossRef Google Scholar
[20]	熊志方. 热带西太平洋硅藻席地球化学: 碳、硅循环及古海洋响应[D]. 中国科学院海洋研究所博士学位论文, 2010. Google Scholar XIONG Zhifang. Geochemistry of diatom mats from tropical West Pacific: Implications for carbon and silicon cycle and response to paleoceanographic conditions[D]. Doctor Dissertation of the Institute of Oceanology, Chinese Academy of Sciences, 2010. Google Scholar
[21]	Xiong Z F, Li T G, Algeo T, et al. Paleoproductivity and paleoredox conditions during late Pleistocene accumulation of laminated diatom mats in the tropical West Pacific [J]. Chemical Geology, 2012, 334: 77-91. doi: 10.1016/j.chemgeo.2012.09.044 CrossRef Google Scholar
[22]	Xiong Z F, Li T G, Algeo T, et al. Rare earth element geochemistry of laminated diatom mats from tropical West Pacific: Evidence for more reducing bottomwaters and higher primary productivity during the Last Glacial Maximum [J]. Chemical Geology, 2012, 296-297: 103-118. doi: 10.1016/j.chemgeo.2011.12.012 CrossRef Google Scholar
[23]	唐琴琴, 詹文欢, 李健, 等. 南海东部边缘火山活动所反映的板片窗构造[J]. 海洋地质与第四纪地质, 2017, 37(2):119-126 Google Scholar TANG Qinqin, ZHAN Wenhuan, LI Jian, et al. Volcanic evidence for slab window induced by fossil ridge subduction at east edge of South China Sea [J]. Marine Geology & Quaternary Geology, 2017, 37(2): 119-126. Google Scholar
[24]	Fryer P. Serpentinite mud volcanism: observations, processes, and implications [J]. Annual Review of Marine Science, 2012, 4(1): 345-373. doi: 10.1146/annurev-marine-120710-100922 CrossRef Google Scholar
[25]	刘鑫, 李三忠, 赵淑娟, 等. 马里亚纳俯冲系统的构造特征[J]. 地学前缘, 2017, 24(4):329-340 Google Scholar LIU Xin, LI Sanzhong, ZHAO Shujuan, et al. Structure of the Mariana subduction system [J]. Earth Science Frontiers, 2017, 24(4): 329-340. Google Scholar
[26]	Shiraki K, Kuroda N, Maruyama S, et al. Evolution of the Tertiary volcanic rocks in the Izu-Mariana arc [J]. Bulletin Volcanologique, 1978, 41(4): 548-562. doi: 10.1007/BF02597386 CrossRef Google Scholar
[27]	刘志兴. 马里亚纳海沟深渊沉积物地球化学特征及其地质意义[D]. 长安大学硕士学位论文, 2019. Google Scholar LIU Zhixing. Geochemical characteristics and geological significance of the hadal trench sediments in the Mariana Trench[D]. Master Dissertation of Chang'an University, 2019. Google Scholar
[28]	Liu R L, Wang L, Wei Y L, et al. The hadal biosphere: Recent insights and new directions [J]. Deep Sea Research Part II:Topical Studies in Oceanography, 2018, 155: 11-18. doi: 10.1016/j.dsr2.2017.04.015 CrossRef Google Scholar
[29]	Warren B A, Owens W B. Deep currents in the central subarctic Pacific Ocean [J]. Journal of Physical Oceanography, 1988, 18(4): 529-551. doi: 10.1175/1520-0485(1988)018<0529:DCITCS>2.0.CO;2 CrossRef Google Scholar
[30]	Kawabe M. Deep water properties and circulation in the western North Pacific [J]. Elsevier Oceanography Series, 1993, 59: 17-37. Google Scholar
[31]	Johnson G C. Deep water properties, velocities, and dynamics over ocean trenches [J]. Journal of Marine Research, 1998, 56(2): 329-347. doi: 10.1357/002224098321822339 CrossRef Google Scholar
[32]	Rea D K, Janecek T R. Mass-accumulation rates of the non-authigenic inorganic crystalline (eolian) component of deep-sea sediments from the western mid-Pacific mountains, deep sea drilling project site 463 [J]. Deep Sea Drilling Project Initial Reports, 1981, 62: 653-659. Google Scholar
[33]	Clemens S C, Prell W L. Late Pleistocene variability of Arabian Sea summer monsoon winds and continental aridity: Eolian records from the lithogenic component of deep-sea sediments [J]. Paleoceanography and Paleoclimatology, 1990, 5(2): 109-145. Google Scholar
[34]	Biscaye P E. Mineralogy and sedimentation of recent deep-sea clay in the Atlantic Ocean and adjacent seas and oceans [J]. Geological Society of America Bulletin, 1965, 76(7): 803-832. doi: 10.1130/0016-7606(1965)76[803:MASORD]2.0.CO;2 CrossRef Google Scholar
[35]	Calvert S E, Pedersen T F, Thunell R C. Geochemistry of the surface sediments of the Sulu and South China Seas [J]. Marine Geology, 1993, 114(3-4): 207-231. doi: 10.1016/0025-3227(93)90029-U CrossRef Google Scholar
[36]	Luo M, Algeo T J, Tong H P, et al. More reducing bottom-water redox conditions during the Last Glacial Maximum in the southern Challenger Deep (Mariana Trench, western Pacific) driven by enhanced productivity [J]. Deep Sea Research Part II:Topical Studies in Oceanography, 2018, 155: 70-82. doi: 10.1016/j.dsr2.2017.01.006 CrossRef Google Scholar
[37]	Jacobsen S B, Wasserburg G J. Sm-Nd isotopic evolution of chondrites [J]. Earth & Planetary Science Letters, 1980, 50(1): 139-155. Google Scholar
[38]	Williams N S, Dixon M F, Johnston D. Reappraisal of the 5 centimetre rule of distal excision for carcinoma of the rectum: A study of distal intramural spread and of patients' survival [J]. British Journal of Surgery, 1983, 70(3): 150-154. Google Scholar
[39]	赵万苍. 东亚沙漠粘粒地球化学研究: 矿物尘来源、传输及其示踪[D]. 南京大学博士学位论文, 2015. Google Scholar ZHAO Wancang. Geochemistry characteristics of clay-sized fractions from East Asian deserts: Mineral dust provenance, transport and tracer[D]. Doctor Dissertation of Nanjing University, 2015. Google Scholar
[40]	Jiang F Q, Frank M, Li T G, et al. Asian dust input in the western Philippine Sea: Evidence from radiogenic Sr and Nd isotopes [J]. Geochemistry, Geophysics, Geosystems, 2013, 14(5): 1538-1551. doi: 10.1002/ggge.20116 CrossRef Google Scholar
[41]	Luo M, Algeo T J, Chen L Y, et al. Role of dust fluxes in stimulating Ethmodiscus rex giant diatom blooms in the northwestern tropical Pacific during the Last Glacial Maximum [J]. Palaeogeography, Palaeoclimatology, Palaeoecology, 2018, 511: 319-331. doi: 10.1016/j.palaeo.2018.08.017 CrossRef Google Scholar
[42]	Jiang Z Z, Sun Z L, Liu Z Q, et al. Rare-earth element geochemistry reveals the provenance of sediments on the southwestern margin of the Challenger Deep [J]. Journal of Oceanology and Limnology, 2019, 37(3): 998-1009. doi: 10.1007/s00343-019-8046-8 CrossRef Google Scholar
[43]	Feng J L, Zhu L P, Zhen X L, et al. Grain size effect on Sr and Nd isotopic compositions in eolian dust: Implications for tracing dust provenance and Nd model age [J]. Geochemical Journal, 2009, 43(2): 123-131. doi: 10.2343/geochemj.1.0007 CrossRef Google Scholar
[44]	Defant M J, Maury R C, Joron J L, et al. The geochemistry and tectonic setting of the northern section of the Luzon arc (the Philippines and Taiwan) [J]. Tectonophysics, 1990, 183(1-4): 187-205. doi: 10.1016/0040-1951(90)90416-6 CrossRef Google Scholar
[45]	Honda M, Yabuki S, Shimizu H. Geochemical and isotopic studies of aeolian sediments in China [J]. Sedimentology, 2004, 51(2): 211-230. doi: 10.1111/j.1365-3091.2004.00618.x CrossRef Google Scholar
[46]	Woodhead J D, Fraser D G. Pb, Sr and ¹⁰Be isotopic studies of volcanic rocks from the Northern Mariana Islands. Implications for magma genesis and crustal recycling in the Western Pacific [J]. Geochimica et Cosmochimica Acta, 1985, 49(9): 1925-1930. doi: 10.1016/0016-7037(85)90087-0 CrossRef Google Scholar
[47]	Woodhead J D. Geochemistry of the Mariana arc (western Pacific): Source composition and processes [J]. Chemical Geology, 1989, 76(1-2): 1-24. doi: 10.1016/0009-2541(89)90124-1 CrossRef Google Scholar
[48]	Chen J, Li G J, Yang J D, et al. Nd and Sr isotopic characteristics of Chinese deserts: Implications for the provenances of Asian dust [J]. Geochimica et Cosmochimica Acta, 2007, 71(15): 3904-3914. doi: 10.1016/j.gca.2007.04.033 CrossRef Google Scholar
[49]	Rao W B, Chen J, Yang J D, et al. Sr-Nd isotopic characteristics of eolian deposits in the Erdos Desert and Chinese Loess Plateau: Implications for their provenances [J]. Geochemical Journal, 2008, 42(3): 273-282. doi: 10.2343/geochemj.42.273 CrossRef Google Scholar
[50]	Nakano T, Yokoo Y, Nishikawa M, et al. Regional Sr-Nd isotopic ratios of soil minerals in northern China as Asian dust fingerprints [J]. Atmospheric Environment, 2004, 38(19): 3061-3067. doi: 10.1016/j.atmosenv.2004.02.016 CrossRef Google Scholar
[51]	Seo I, Lee Y I, Yoo C M, et al. Sr-Nd isotope composition and clay mineral assemblages in eolian dust from the central Philippine Sea over the last 600 kyr: Implications for the transport mechanism of Asian dust [J]. Journal of Geophysical Research:Atmospheres, 2014, 119(19): 11492-11504. doi: 10.1002/2014JD022025 CrossRef Google Scholar
[52]	Allegre C J, Othman D B, Polve M, et al. The Nd-Sr isotopic correlation in mantle materials and geodynamic consequences [J]. Physics of the Earth & Planetary Interiors, 1979, 19(4): 293-306. Google Scholar
[53]	Xiong Z F, Li T G, Algeo T, et al. The silicon isotope composition of Ethmodiscus rex laminated diatom mats from the tropical West Pacific: Implications for silicate cycling during the Last Glacial Maximum [J]. Paleoceanography, 2015, 30(7): 803-823. doi: 10.1002/2015PA002793 CrossRef Google Scholar
[54]	Xu Z K, Wan S M, Colin C, et al. Enhanced terrigenous organic matter input and productivity on the western margin of the Western Pacific Warm Pool during the Quaternary sea-level lowstands: Forcing mechanisms and implications for the global carbon cycle [J]. Quaternary Science Reviews, 2020, 232: 106211. doi: 10.1016/j.quascirev.2020.106211 CrossRef Google Scholar
[55]	Yu Z J, Wan S M, Colin C, et al. ENSO-like modulated tropical Pacific climate changes since 2.36 Myr and its implication for the middle Pleistocene transition [J]. Geochemistry, Geophysics, Geosystems, 2018, 19(2): 415-426. doi: 10.1002/2017GC007247 CrossRef Google Scholar
[56]	Xiong Z F, Li T G, Jiang F Q, et al. Millennial-scale evolution of elemental ratios in bulk sediments from the western Philippine Sea and implications for chemical weathering in Luzon since the Last Glacial Maximum [J]. Journal of Asian Earth Sciences, 2019, 179: 127-137. doi: 10.1016/j.jseaes.2019.04.021 CrossRef Google Scholar
[57]	Xiong Z F, Li T G, Chang F M, et al. Rapid precipitation changes in the tropical West Pacific linked to North Atlantic climate forcing during the last deglaciation [J]. Quaternary Science Reviews, 2018, 197: 288-306. doi: 10.1016/j.quascirev.2018.07.040 CrossRef Google Scholar
[58]	张富元, 李安春, 林振宏, 等. 深海沉积物分类与命名[J]. 海洋与湖沼, 2006, 37(6):517-523 doi: 10.3321/j.issn:0029-814X.2006.06.007 CrossRef Google Scholar ZHANG Fuyuan, LI Anchun, LIN Zhenhong, et al. Classification and nomenclature of deep sea sediments [J]. Oceanologia et Limnologia Sinica, 2006, 37(6): 517-523. doi: 10.3321/j.issn:0029-814X.2006.06.007 CrossRef Google Scholar
[59]	刘华华. 中新世以来奄美三角盆地沉积物中粘土矿物的来源[D]. 中国科学院海洋研究所硕士学位论文, 2016. Google Scholar LIU Huahua. Provenance of clay minerals in the sediments from the Amami Sankaku Basin since Miocene[D]. Master Dissertation of the Institute of Oceanology, Chinese Academy of Sciences, 2016. Google Scholar
[60]	王银, 吕士辉, 苏新, 等. 西北太平洋多金属结核区沉积物黏土矿物特征[J]. 中国有色金属学报, 2021, 31(10):2696-2712 Google Scholar WANG Yin, LÜ Shihui, SU Xin, et al. Assemblage of clay minerals at polymetallic nodules contract area in Northwest Pacific Ocean [J]. The Chinese Journal of Nonferrous Metals, 2021, 31(10): 2696-2712. Google Scholar
[61]	Liu Z F, Zhao Y L, Colin C, et al. Chemical weathering in Luzon, Philippines from clay mineralogy and major-element geochemistry of river sediments [J]. Applied Geochemistry, 2009, 24(11): 2195-2205. doi: 10.1016/j.apgeochem.2009.09.025 CrossRef Google Scholar
[62]	Biscaye P E, Grousset F E, Revel M, et al. Asian provenance of glacial dust (stage 2) in the Greenland Ice Sheet Project 2 Ice Core, Summit, Greenland [J]. Journal of Geophysical Research:Oceans, 1997, 102(C12): 26765-26781. doi: 10.1029/97JC01249 CrossRef Google Scholar
[63]	German C R, Elderfield H. Rare earth elements in Saanich Inlet, British Columbia, a seasonally anoxic basin [J]. Geochimica et Cosmochimica Acta, 1989, 53(10): 2561-2571. doi: 10.1016/0016-7037(89)90128-2 CrossRef Google Scholar
[64]	German C R, Holliday B P, Elderfield H. Redox cycling of rare earth elements in the suboxic zone of the Black Sea [J]. Geochimica et Cosmochimica Acta, 1991, 55(12): 3553-3558. doi: 10.1016/0016-7037(91)90055-A CrossRef Google Scholar
[65]	Alibo D S, Nozaki Y. Rare earth elements in seawater: particle association, shale-normalization, and Ce oxidation [J]. Geochimica et Cosmochimica Acta, 1999, 63(3-4): 363-372. doi: 10.1016/S0016-7037(98)00279-8 CrossRef Google Scholar
[66]	Nozaki Y. Rare Earth Elements and their Isotopes in the Ocean[M]//Encyclopedia of Ocean Sciences. San Diego: Academic Press, 2001: 2354-2366. Google Scholar
[67]	Luo M, Gieskes J, Chen L Y, et al. Sources, degradation, and transport of organic matter in the New Britain shelf-trench continuum, Papua New Guinea [J]. Journal of Geophysical Research:Biogeosciences, 2019, 124(6): 1680-1695. doi: 10.1029/2018JG004691 CrossRef Google Scholar