孟加拉湾中部表层沉积物有机碳分布特征及来源
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摘要
通过对孟加拉湾中部110个表层沉积物样品有机碳、氮含量及粒度进行测试分析,揭示了研究区表层沉积物平均粒径、有机碳(TOC)、总氮(TN)、有机碳/总氮(TOC/TN)的分布特征,并讨论了其有机质来源及控制因素。结果表明,研究区表层沉积物的平均粒径值为6.2~7.6Φ,平均为7.1Φ,其分布呈现出以16°N和15°N为界南北两侧海域粒度相对较细(>7Φ),中间海域相对较粗(<7Φ)的特点;研究区TOC的质量分数为0.37%~1.24%,平均为0.84%,TN质量分数为0.05%~0.15%,平均为0.10%,两者分布特点相似,大致以15°N和16°N为界表现出南北两侧海域高,中间海域低的特点;TOC/TN比值为6.05~12.88,平均为8.38,中部海域比值高,南北两侧低。根据TOC/TN比值估算研究区陆源和海洋自生有机质的贡献,结果表明研究区陆源与海洋自生有机质平均相对贡献分别为60%和40%。研究区有机质的分布主要受控于有机质来源及输运方式,其中浊流输运导致的溢流沉积是其最主要的控制因素。另外,粒度、河流悬浮体的输入沉降和有机质保存条件等因素也起着重要作用。
This study analyzed total organic carbon(TOC),total nitrogen(TN)and grain size of 110 surface samples from the mid-Bengal Bay,indicated their distributional patterns of some proxies such as mean grain size(Mz),TOC,TN and TOC/TN,and then discussed the origin of organic matter and its controlling factors.The Mz varies in a range of 6.2~7.6Φ,with an average of 7.1Φ.The distribution features of Mz,TOC,TN and TOC/TN are generally similar,and all of them show the same two " boundaries" :15°N and16°N,And,based on these two boundaries,the study area can be subdivided into the following three parts,northern,central and southern area.For Mz,it is fine-grained in the northern and southern areas(>7Φ)and coarse in the central area(<7Φ).Contents of TOC and TN vary in a range of 0.37%~1.24% with an average of 0.84% and 0.05%~0.15% with an average of 0.10%,respectively.Compared to those in the central area,the contents of both TOC and TN in the northern and southern areas are higher.TOC/TN varies in a range of 6.05~12.88 with an average of 8.38,which are higher in the central area than the northern and southern areas.According to the TOC/TN ratios,we estimated the average contributions of terrigenous and oceanic organic matter to the study area,60% and 40%,respectively.We suggested that the distribution pattern of organic matter in the study area are mainly controlled by material sources and supply paths,and the most important factor is the overflowing sediments caused by turbidity currents.In addition,some other factors such as grain size,sedimentation of suspended materials(carried by the river plume)and preservation conditions for organic matters,play important role as well.
This study analyzed total organic carbon(TOC),total nitrogen(TN)and grain size of 110 surface samples from the mid-Bengal Bay,indicated their distributional patterns of some proxies such as mean grain size(Mz),TOC,TN and TOC/TN,and then discussed the origin of organic matter and its controlling factors.The Mz varies in a range of 6.2~7.6Φ,with an average of 7.1Φ.The distribution features of Mz,TOC,TN and TOC/TN are generally similar,and all of them show the same two " boundaries" :15°N and16°N,And,based on these two boundaries,the study area can be subdivided into the following three parts,northern,central and southern area.For Mz,it is fine-grained in the northern and southern areas(>7Φ)and coarse in the central area(<7Φ).Contents of TOC and TN vary in a range of 0.37%~1.24% with an average of 0.84% and 0.05%~0.15% with an average of 0.10%,respectively.Compared to those in the central area,the contents of both TOC and TN in the northern and southern areas are higher.TOC/TN varies in a range of 6.05~12.88 with an average of 8.38,which are higher in the central area than the northern and southern areas.According to the TOC/TN ratios,we estimated the average contributions of terrigenous and oceanic organic matter to the study area,60% and 40%,respectively.We suggested that the distribution pattern of organic matter in the study area are mainly controlled by material sources and supply paths,and the most important factor is the overflowing sediments caused by turbidity currents.In addition,some other factors such as grain size,sedimentation of suspended materials(carried by the river plume)and preservation conditions for organic matters,play important role as well.
引文
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[11]CURRAY J R.The Bengal depositional system:from rift to orogeny[J].Marine Geology,2014,352(2):59-69.
[12]GOODBRED S L.Response of the Ganges dispersal system to climate change:a source-to-sink view since the last interstade[J].Sedimentary Geology,2003,162(1):83-104.
[13]KOLLA V,MOORE D G,CURRAY J R.Recent bottom-current activity in the deep western Bay of Bengal[J].Marine Geology,1976,21(4):255-270.
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[15]MCMANUS J.Grain size determination and interpretation[M]∥TUCKER M.Techniques in Sedimentology.Oxford:Blackwell,1988:63-85.
[16]MAYER L M.Surface area control of organic carbon accumulation in continental shelf sediments[J].Geochimica et Cosmochimica Acta,1994,58(4):1271-1284.
[17]CURRAY J R,EMMEL F J,MOORE D G.The Bengal Fan:morphology,geometry,stratigraphy,history and processes[J].Marine&Petroleum Geology,2002,19(10):1191-1223.
[18]REDFIELD A C.The influence of organisms on the composition of sea water[J].The Sea,1963,2:26-77.
[19]MEYERS P A.Organic geochemical proxies of paleoceanographic,paleolimnologic,and paleoclimatic processes[J].Organic Geochemistry,1997,27(97):213-250.
[20]GAO J H,WANG Y P,PAN S M,et al.Source and distribution of organic matter in seabed sediments of the Changjiang river estuary and its adjacent sea area[J].Acta Geographica Sinica,2007,62(9):981-991.高建华,汪亚平,潘少明,等.长江口外海域沉积物中有机物的来源及分布[J].地理学报,2007,62(9):981-991.
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[22]JIA G D,PENG P A,FU J M.Sedimentary records of accelerated eutrophication for the last 100years at the Pearl River Estuary[J].Quaternary Science,2002,22(2):158-165.贾国东,彭平安,傅家谟.珠江口近百年来富营养化加剧的沉积记录[J].第四纪研究,2002,22(2):158-165.
[23]LX X,ZHAI S K,NIU L F.Study on the C/N ratios of organic matters in the core sediments of the Yangtze River Estuary[J].Environmental Chemistry,2005,24(3):255-259.吕晓霞,翟世奎,牛丽凤.长江口柱状沉积物中有机质C/N比的研究[J].环境化学,2005,24(3):255-259.
[24]RAMESH R,PURVAJA G R,SUBRAMANIAN V.Carbon and phosphorus transport by the major Indian rivers[J].Journal of Biogeography,1995,22(2/3):409-415.
[25]BALAKRISHNA K,PROBST J L.Organic carbon transport and C/N ratio variations in a large tropical river:Godavari as a case study,India[J].Biogeochemistry,2005,73(3):457-473.
[26]ANAWAR H M,YOSHIOKA T,KONOHIRA E,et al.Sources of organic carbon and depositional environment in the Bengal delta plain sediments during the Holocene period[J].Limnology,2010,11(2):133-142.
[27]GEIDER R,ROCHE J L.Redfield revisited:Variability of C∶N∶P in marine microalgae and its biochemical basis[J].European Journal of Phycology,2002,37(1):1-17.
[28]TAKAHASHI T,BROECKER W S,LANGER S.Redfield ratio based on chemical data from isopycnal surfaces[J].Journal of Geophysical Research,1985,90(4):6907-6924.
[29]MINSTER J F,BOULAHDID M.Redfield ratios along isopycnal surfaces-a complementary study[J].Deep Sea Research Part A:Oceanographic Research Papers,1987,34(12):1981-2003.
[30]BOULAHDID M,MINSTER J F.Oxygen consumption and nutrient regeneration ratios along isopycnal horizons in the Pacific Ocean[J].Marine Chemistry,1989,26(2):133-153.
[31]ANDERSON L A,SARMIENTO J L.Redfield ratios of remineralization determined by nutrient data-analysis[J].Global Biogeochemical Cycles,1994,8(1):65-80.
[32]FRANCE L C,DERRY L A.δ13C of organic carbon in the Bengal Fan:Source evolution and transport of C3and C4plant carbon to marine sediments[J].Geochimica et Cosmochimica Acta,1994,58(21):4809-4814.
[33]CURRAY J R,MOORE D G.Growth of the Bengal deep-sea fan and denudation in the Himalayas[J].Geological Society of America Bulletin,1971,82(3):563-572.
[34]CURRAY J R.Possible greenschist metamorphism at the base of a 22-km sedimentary section,Bay of Bengal[J].Geology,1991,19(11):1097.
[35]CURRAY J R,EMMEL F J,MOORE D G,et al.Structure,tectonics,and geological history of the northeastern Indian Ocean[M]∥The Ocean Basins and Margins.US:Springer,1982:399-450.
[36]EMMEL F J,CURRAY J R.Submarine Fans and Related Turbidite Systems[M].New York:Springer,1985.
[37]GOODBREAD JR S L,KUEHL S A.Holocene and modern sediment budgets for the Ganges-Brahmaputra river system:evidence for highstand dispersal to flood-plain,shelf and deep-sea depocenters[J].Geology,1999,27(6):559-562.
[38]WEBER M E,WIEDICKE M H,KUDRASS H R,et al.Active growth of the Bengal Fan during sea-level rise and highstand[J].Geology,1997,25(4):315-318.
[39]ITTEKKOT V,NAIR R R,HONJO S,et al.Enhanced particle fluxes in Bay of Bengal induced by injection of fresh water[J].Nature,1991,351(6325):385-387.
[40]JENNERJAHN T C,ITTEKKOT V.Changes in organic matter from surface waters to continental slope sediments off the Sao Francisco River,eastern Brazil[J].Marine Geology,1999,161(2-4):129-140.
[41]CONTRERAS-ROSALES L A,JENNERJAHN T,THARAMMAL T,et al.Evolution of the Indian Summer Monsoon and terrestrial vegetation in the Bengal region during the past 18ka[J].Quaternary Science Reviews,2014(102):133-148.
[42]CHEN J F.Biogeochemistry of settling particles in the South China Sea and its significance for paleo-environment studies[D].Shanghai:Tongji University,2005:58-73.陈建芳.南海沉降颗粒物的生物地球化学过程及其在古环境研究中的意义[D].上海:同济大学,2005:58-73.
[43]UNGER D,ITTEKKOT V,SCHAFER P,et al.Seasonality and interannual variability of particle fluxes to the deep Bay of Bengal:Influence of riverine input and oceanographic processes[J].Deep Sea Research Part II:Topical Studies in Oceanography,2003,50(5):897-923.
[44]JIANG H H.Study on biogenic elements in sediments of the Bohai Sea[D].Qingdao:Ocean University of China,2012:54-59.江辉煌.渤海沉积物中生源要素的研究[D].青岛:中国海洋大学,2012:54-59.
[45]FANG N Q,CHEN P,WU L,et al.Contour currents in deep-water records from Bay of Bengal and its environmental implication[J].Earth Science-Journal of China University of Geosciences,2004,27(5):570-575.方念乔,陈萍,吴琳,等.孟加拉湾深海记录中的等深流活动特征及其环境意义初探[J].地球科学,2004,27(5):570-575.
[46]HAN B,LI X J,L J R,et al.Petroleum exploration potential in the Bay of Bengal deep water basin[J].Marine Geology Frontiers,2012(4):50-56.韩冰,李学杰,吕建荣,等.孟加拉湾深水盆地油气勘探潜力[J].海洋地质前沿,2012(4):50-56.
[2]HU D X,YANG Z S.Key process of ocean flux in the East China Sea[M].Beijing:Ocean Press,2001:1-10.胡敦欣,杨作升.东海海洋通量关键过程[M].北京:海洋出版社,2001:1-10.
[3]HU L M,GUO Z G,FENG J L,et al.Distributions and sources of bulk organic matter and aliphatic hydrocarbons in surface sediments of the Bohai Sea,China[J].Marine Chemistry,2009,113(3):197-211.
[4]GALY V,FRANCE L C,BEYSSAC O,et al.Efficient organic carbon burial in the Bengal fan sustained by the Himalayan erosional system[J].Nature,2007,450(7168):407-410.
[5]FRANCE L C,DERRY L A.Organic carbon burial forcing of the carbon cycle from Himalayan erosion[J].Nature,1997(6655):65-67.
[6]DATTA D K,GUPTA L P,SUBRAMANIAN V.Distribution of C,N and P in the sediments of the Ganges-Brahmaputra-Meghna river system in the Bengal basin[J].Organic Geochemistry,1999,30(98):75-82.
[7]CHAUHAN O S,VOGELSANG E.Climate induced changes in the circulation and dispersal patterns of the fluvial sources during late Quaternary in the middle Bengal Fan[J].Journal of Earth System Science,2006,115(3):379-386.
[8]RAMAGE C S.Monsoon Meteorology[M].New York:Academic Press,1971:296.
[9]WYRTKI K.Physical Oceanography of the Indian Ocean[M]∥The Biology of the Indian Ocean.Berlin:Springer Berlin Heidelberg,1973:18-36.
[10]BURDIGE,DAVID J.Burial of terrestrial organic matter in marine sediments:A re-assessment[J].Global Biogeochemical Cycles,2005,19(4):922-932.
[11]CURRAY J R.The Bengal depositional system:from rift to orogeny[J].Marine Geology,2014,352(2):59-69.
[12]GOODBRED S L.Response of the Ganges dispersal system to climate change:a source-to-sink view since the last interstade[J].Sedimentary Geology,2003,162(1):83-104.
[13]KOLLA V,MOORE D G,CURRAY J R.Recent bottom-current activity in the deep western Bay of Bengal[J].Marine Geology,1976,21(4):255-270.
[14]ZHANG Z F.Sedimentary records and paleoclimate evolution of Bay of Bengal since Pliocene time[D].Beijing:China University of Geosciences,2002.张振芳.孟加拉湾上新世以来沉积记录及古气候演化[D].北京:中国地质大学,2002.
[15]MCMANUS J.Grain size determination and interpretation[M]∥TUCKER M.Techniques in Sedimentology.Oxford:Blackwell,1988:63-85.
[16]MAYER L M.Surface area control of organic carbon accumulation in continental shelf sediments[J].Geochimica et Cosmochimica Acta,1994,58(4):1271-1284.
[17]CURRAY J R,EMMEL F J,MOORE D G.The Bengal Fan:morphology,geometry,stratigraphy,history and processes[J].Marine&Petroleum Geology,2002,19(10):1191-1223.
[18]REDFIELD A C.The influence of organisms on the composition of sea water[J].The Sea,1963,2:26-77.
[19]MEYERS P A.Organic geochemical proxies of paleoceanographic,paleolimnologic,and paleoclimatic processes[J].Organic Geochemistry,1997,27(97):213-250.
[20]GAO J H,WANG Y P,PAN S M,et al.Source and distribution of organic matter in seabed sediments of the Changjiang river estuary and its adjacent sea area[J].Acta Geographica Sinica,2007,62(9):981-991.高建华,汪亚平,潘少明,等.长江口外海域沉积物中有机物的来源及分布[J].地理学报,2007,62(9):981-991.
[21]CHEN B,HU L M,DENG S G,et al.Organic carbon in surface sediments of the Bohai Bay,China and its contribution to sedimentation[J].Marine Geology&Quaternary Geology,2011,31(5):37-42.陈彬,胡利民,邓声贵,等.渤海湾表层沉积物中有机碳的分布与物源贡献估算[J].海洋地质与第四纪地质,2011,31(5):37-42.
[22]JIA G D,PENG P A,FU J M.Sedimentary records of accelerated eutrophication for the last 100years at the Pearl River Estuary[J].Quaternary Science,2002,22(2):158-165.贾国东,彭平安,傅家谟.珠江口近百年来富营养化加剧的沉积记录[J].第四纪研究,2002,22(2):158-165.
[23]LX X,ZHAI S K,NIU L F.Study on the C/N ratios of organic matters in the core sediments of the Yangtze River Estuary[J].Environmental Chemistry,2005,24(3):255-259.吕晓霞,翟世奎,牛丽凤.长江口柱状沉积物中有机质C/N比的研究[J].环境化学,2005,24(3):255-259.
[24]RAMESH R,PURVAJA G R,SUBRAMANIAN V.Carbon and phosphorus transport by the major Indian rivers[J].Journal of Biogeography,1995,22(2/3):409-415.
[25]BALAKRISHNA K,PROBST J L.Organic carbon transport and C/N ratio variations in a large tropical river:Godavari as a case study,India[J].Biogeochemistry,2005,73(3):457-473.
[26]ANAWAR H M,YOSHIOKA T,KONOHIRA E,et al.Sources of organic carbon and depositional environment in the Bengal delta plain sediments during the Holocene period[J].Limnology,2010,11(2):133-142.
[27]GEIDER R,ROCHE J L.Redfield revisited:Variability of C∶N∶P in marine microalgae and its biochemical basis[J].European Journal of Phycology,2002,37(1):1-17.
[28]TAKAHASHI T,BROECKER W S,LANGER S.Redfield ratio based on chemical data from isopycnal surfaces[J].Journal of Geophysical Research,1985,90(4):6907-6924.
[29]MINSTER J F,BOULAHDID M.Redfield ratios along isopycnal surfaces-a complementary study[J].Deep Sea Research Part A:Oceanographic Research Papers,1987,34(12):1981-2003.
[30]BOULAHDID M,MINSTER J F.Oxygen consumption and nutrient regeneration ratios along isopycnal horizons in the Pacific Ocean[J].Marine Chemistry,1989,26(2):133-153.
[31]ANDERSON L A,SARMIENTO J L.Redfield ratios of remineralization determined by nutrient data-analysis[J].Global Biogeochemical Cycles,1994,8(1):65-80.
[32]FRANCE L C,DERRY L A.δ13C of organic carbon in the Bengal Fan:Source evolution and transport of C3and C4plant carbon to marine sediments[J].Geochimica et Cosmochimica Acta,1994,58(21):4809-4814.
[33]CURRAY J R,MOORE D G.Growth of the Bengal deep-sea fan and denudation in the Himalayas[J].Geological Society of America Bulletin,1971,82(3):563-572.
[34]CURRAY J R.Possible greenschist metamorphism at the base of a 22-km sedimentary section,Bay of Bengal[J].Geology,1991,19(11):1097.
[35]CURRAY J R,EMMEL F J,MOORE D G,et al.Structure,tectonics,and geological history of the northeastern Indian Ocean[M]∥The Ocean Basins and Margins.US:Springer,1982:399-450.
[36]EMMEL F J,CURRAY J R.Submarine Fans and Related Turbidite Systems[M].New York:Springer,1985.
[37]GOODBREAD JR S L,KUEHL S A.Holocene and modern sediment budgets for the Ganges-Brahmaputra river system:evidence for highstand dispersal to flood-plain,shelf and deep-sea depocenters[J].Geology,1999,27(6):559-562.
[38]WEBER M E,WIEDICKE M H,KUDRASS H R,et al.Active growth of the Bengal Fan during sea-level rise and highstand[J].Geology,1997,25(4):315-318.
[39]ITTEKKOT V,NAIR R R,HONJO S,et al.Enhanced particle fluxes in Bay of Bengal induced by injection of fresh water[J].Nature,1991,351(6325):385-387.
[40]JENNERJAHN T C,ITTEKKOT V.Changes in organic matter from surface waters to continental slope sediments off the Sao Francisco River,eastern Brazil[J].Marine Geology,1999,161(2-4):129-140.
[41]CONTRERAS-ROSALES L A,JENNERJAHN T,THARAMMAL T,et al.Evolution of the Indian Summer Monsoon and terrestrial vegetation in the Bengal region during the past 18ka[J].Quaternary Science Reviews,2014(102):133-148.
[42]CHEN J F.Biogeochemistry of settling particles in the South China Sea and its significance for paleo-environment studies[D].Shanghai:Tongji University,2005:58-73.陈建芳.南海沉降颗粒物的生物地球化学过程及其在古环境研究中的意义[D].上海:同济大学,2005:58-73.
[43]UNGER D,ITTEKKOT V,SCHAFER P,et al.Seasonality and interannual variability of particle fluxes to the deep Bay of Bengal:Influence of riverine input and oceanographic processes[J].Deep Sea Research Part II:Topical Studies in Oceanography,2003,50(5):897-923.
[44]JIANG H H.Study on biogenic elements in sediments of the Bohai Sea[D].Qingdao:Ocean University of China,2012:54-59.江辉煌.渤海沉积物中生源要素的研究[D].青岛:中国海洋大学,2012:54-59.
[45]FANG N Q,CHEN P,WU L,et al.Contour currents in deep-water records from Bay of Bengal and its environmental implication[J].Earth Science-Journal of China University of Geosciences,2004,27(5):570-575.方念乔,陈萍,吴琳,等.孟加拉湾深海记录中的等深流活动特征及其环境意义初探[J].地球科学,2004,27(5):570-575.
[46]HAN B,LI X J,L J R,et al.Petroleum exploration potential in the Bay of Bengal deep water basin[J].Marine Geology Frontiers,2012(4):50-56.韩冰,李学杰,吕建荣,等.孟加拉湾深水盆地油气勘探潜力[J].海洋地质前沿,2012(4):50-56.