Response of sediment grain size composition of the Zhe-Min coastal mud to the sediment load reduction of the Changjiang River entering the sea
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摘要: 自1950年以来,长江入海输沙量呈阶段性减少趋势;作为长江远端泥,长江入海输沙量的“减沙”效应在浙闽沿岸泥质区是否有相应的沉积信号?若有,该如何进行提取和解译?为探讨以上问题,在浙闽沿岸泥质区采集柱状样5根,进行了高分辨率(2 mm)的粒度测试,并通过端元分析手段分离出4个端元。结合研究区物源及水动力的空间差异,发现各端元有其特定的指示意义:EM1组分(众数粒径约为2 μm)为长江来源的极细粒物质;EM2组分(众数粒径约为10 μm)主要为长江及浙闽沿岸中小河流的细颗粒物质,但以长江为主;EM3组分(众数粒径约为80 μm)主要为台湾暖流带来的较粗粒物质;EM4组分(众数粒径约为200 μm)为长江输运的粗颗粒物质。进一步分析发现,EM1组分对长江入海输沙量的阶段性减少有较好的响应关系:由浙闽泥质区北部至南部响应强度依次降低;在响应时间上存在滞后现象,且从北到南滞后时间增加,由北部的4~6年增加至南部的10~14年。总体来看,细颗粒组分更能反映长江流域变化信息,且泥质区的不同位置对流域变化信息的响应强度差异显著。Abstract: Since 1950, the sediment load of the Changjiang River entering the sea has been stepwise decreasing. As the distal mud of the Changjiang River, whether the signal of “sediment load reduction” was recorded in the Zhe-Min coastal mud? If so, how to extract and interpret these sedimentary information? In order to discussing this scientific problem, 5 sediment cores were collected in the Zhe-Min coastal mud; in addition, high resolution grain size analysis (2 mm) was conducted, and four end members were obtained through end-member (EM) model decomposing. Combined with the analysis of the spatial discrepancy in provenance and hydrodynamics of the study area, the specific indicative significance of each EM was revealed: EM1 (with the modal grain size about 2 μm) is originated from extremely fine-grained sediment of the Changjiang River; EM2’s (with the modal grain size about 10 μm) origin is predominated by the Changjiang River, and small part is contributed by the middle and small sized rivers of Zhe-Min coast; EM3 (with the modal grain size about 80 μm) mainly consists of coarse-grain sediment might be provided by Taiwan Warm Current; EM4 (with the modal grain size about 200 μm) is also characterized by coarse-grain sediment, and may be contributed by the Changjiang River. Further analysis indicated that, the EM1 variation was in agreement with the sediment stepwise reduction of the Changjiang River; however, the response intensity gradually decreased from the north to the south. In addition, the hysteresis existed in response time, and the retardation time increased from 4−6 years in the north to 10−14 years in the south. In general, fine-grained sediment could better reflect the Changjiang River catchment change information, and response intensity exhibited significant difference in different areas of the Zhe-Min coastal mud.
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图 1 研究区流系及采样点分布图(★为采样位置)
改绘自文献[23-24];a:浙闽沿岸流;b:台湾暖流;c:黑潮;d:黑潮入侵分支;e:台湾物质可能的影响区域
Fig. 1 Current systems and sampling distribution of the study area (★ represents the sampling position)
Modified from references [23-24]; a: Zhe-Min Coastal Current; b: Taiwan Warm Current; c: Kuroshio; d: the branch of Kuroshio intrusion; e: possible area of impact of Taiwanese material
表 1 柱状样信息
Tab. 1 The information of sample columns
柱状样编号 纬度 经度 水深/m 长度/cm S1 29.55°N 122.80°E 58 38 S2 28.47°N 122.58°E 65 43 S3 27.63°N 121.90°E 65 36 S4 26.82°N 121.23°E 65 41 S5 26.18°N 120.15°E 28 46 表 2 端元拟合结果
Tab. 2 The results of end member unmixing
No. of EMS EM R2 R2 Theta 2 1.742×10−6 0.956 9.650 3 9.311×10−3 0.979 6.723 4 0.0205 0.996 3.044 5 0.182 0.998 1.896 6 0.108 0.999 1.342 注:No. of EMS为拟合端元数量;EM R2为所有拟合端元之间线性平方相关性的最大值;R2为测量数据集和拟合的端元数据集之间的线性平方相关性;Theta为测量数据集和拟合端元数据集之间的角度距离。 -
[1] 高抒. 海岸与陆架沉积: 动力过程、全球变化影响和地层记录[J]. 第四纪研究, 2010, 30(5): 856−863. doi: 10.3969/j.issn.1001-7410.2010.05.01Gao Shu. Coastal and shelf sedimentation in association with dynamic processes, global change impacts, and stratigraphic records: an overview of the scientific problems[J]. Quaternary Sciences, 2010, 30(5): 856−863. doi: 10.3969/j.issn.1001-7410.2010.05.01 [2] 石学法, 刘升发, 乔淑卿, 等. 东海闽浙沿岸泥质区沉积特征与古环境记录[J]. 海洋地质与第四纪地质, 2010, 30(4): 19−30.Shi Xuefa, Liu Shengfa, Qiao Shuqing, et al. Depositional features and palaeoenvironmental records of the mud deposits in Min-Zhe coastal mud area, East China Sea[J]. Marine Geology & Quaternary Geology, 2010, 30(4): 19−30. [3] 徐方建, 李安春, 万世明, 等. 东海内陆架泥质区中全新世环境敏感粒度组分的地质意义[J]. 海洋学报, 2009, 31(3): 95−102.Xu Fangjian, Li Anchun, Wan Shiming, et al. The geological significance of environmental sensitive grain-size populations in the mud wedge of the East China Sea during the mid-Holocene[J]. Haiyang Xuebao, 2009, 31(3): 95−102. [4] 乔璐璐, 史经昊, 高飞, 等. 我国陆架泥质区沉积动力数值模拟研究进展[J]. 海洋地质与第四纪地质, 2014, 34(3): 155−166.Qiao Lulu, Shi Jinghao, Gao Fei, et al. Numerical simulation of sediment dynamic processes for mud areas on the East China Sea continental shelves: A review[J]. Marine Geology & Quaternary Geology, 2014, 34(3): 155−166. [5] 刘升发, 石学法, 刘焱光, 等. 中全新世以来东亚冬季风的东海内陆架泥质沉积记录[J]. 科学通报, 2010, 55(21): 2306−2314. doi: 10.1007/s11434-010-3215-3Liu Shengfa, Shi Xuefa, Liu Yan’guang, et al. Records of the East Asian winter monsoon from the mud area on the inner shelf of the East China Sea since the mid-Holocene[J]. Chinese Science Bulletin, 2010, 55(21): 2306−2314. doi: 10.1007/s11434-010-3215-3 [6] Gao Jianhua, Jia Jianjun, Kettner A J, et al. Reservoir-induced changes to fluvial fluxes and their downstream impacts on sedimentary processes: the Changjiang (Yangtze) River, China[J]. Quaternary International, 2018, 493: 187−197. doi: 10.1016/j.quaint.2015.03.015 [7] Gao J H, Jia J J, Wang Y P, et al. Variations in quantity, composition and grain size of Changjiang sediment discharging into the sea in response to human activities[J]. Hydrology and Earth System Sciences, 2015, 19(2): 645−655. doi: 10.5194/hess-19-645-2015 [8] Jia Jianjun, Gao Jianhua, Cai Tinglu, et al. Sediment accumulation and retention of the Changjiang (Yangtze River) subaqueous delta and its distal muds over the last century[J]. Marine Geology, 2018, 401: 2−16. doi: 10.1016/j.margeo.2018.04.005 [9] 杨阳, 高抒, 周亮, 等. 海南新村港潟湖表层沉积物粒度特征及其沉积环境[J]. 海洋学报, 2016, 38(1): 94−105.Yang Yang, Gao Shu, Zhou Liang, et al. Grain size distribution of surface sediments and sedimentary environment in the lagoon of Xincun, Hainan Island[J]. Haiyang Xuebao, 2016, 38(1): 94−105. [10] Weltje G J. End-member modeling of compositional data: numerical-statistical algorithms for solving the explicit mixing problem[J]. Mathematical Geology, 1997, 29(4): 503−549. doi: 10.1007/BF02775085 [11] Weltje G J, Prins M A. Muddled or mixed? Inferring palaeoclimate from size distributions of deep-sea clastics[J]. Sedimentary Geology, 2003, 162(1/2): 39−62. [12] 张晓东, 许淑梅, 翟世奎, 等. 东海内陆架沉积气候信息的端元分析模型反演[J]. 海洋地质与第四纪地质, 2006, 26(2): 25−32.Zhang Xiaodong, Xu Shumei, Zhai Shikui, et al. The inversion of climate information from the sediment of inner shelf of East China Sea using end-member model[J]. Marine Geology & Quaternary Geology, 2006, 26(2): 25−32. [13] 张晓东, 翟世奎, 许淑梅. 端元分析模型在长江口邻近海域沉积物粒度数据反演方面的应用[J]. 海洋学报, 2006, 28(4): 159−166.Zhang Xiaodong, Zhai Shikui, Xu Shumei. The application of grain-size end-member modeling to the shelf near the estuary of Changjiang River in China[J]. Haiyang Xuebao, 2006, 28(4): 159−166. [14] 薛成凤, 贾建军, 高抒, 等. 中小河流对长江水下三角洲远端泥沉积的贡献: 以椒江和瓯江为例[J]. 海洋学报, 2018, 40(5): 75−89.Xue Chengfeng, Jia Jianjun, Gao Shu, et al. The contribution of middle and small rivers to the distal mud of subaqueous Changjiang Delta: Results from Jiaojiang River and Oujiang River[J]. Haiyang Xuebao, 2018, 40(5): 75−89. [15] 王可, 郑洪波, Prins M, 等. 东海内陆架泥质沉积反映的古环境演化[J]. 海洋地质与第四纪地质, 2008, 28(4): 1−10.Wang Ke, Zheng Hongbo, Prins M, et al. High-resolution paleoenvironmental record of the mud sediments of the East China Sea inner shelf[J]. Marine Geology & Quaternary Geology, 2008, 28(4): 1−10. [16] 赵松, 常凤鸣, 李铁刚, 等. 粒度端元法在东海内陆架古环境重建中的应用[J]. 海洋地质与第四纪地质, 2017, 37(3): 187−196.Zhao Song, Chang Fengming, Li Tiegang, et al. The application of grain-size end member algorithm to paleoenvironmental reconstruction on inner shelf of East China Sea[J]. Marine Geology & Quaternary Geology, 2017, 37(3): 187−196. [17] Paterson G A, Heslop D. New methods for unmixing sediment grain size data[J]. Geochemistry, Geophysics, Geosystems, 2015, 16(12): 4494−4506. doi: 10.1002/2015GC006070 [18] Liu J P, Li A C, Xu K H, et al. Sedimentary features of the Yangtze River-derived along-shelf clinoform deposit in the East China Sea[J]. Continental Shelf Research, 2006, 26(17/18): 2141−2156. [19] Liu J P, Xu K H, Li A C, et al. Flux and fate of Yangtze river sediment delivered to the East China Sea[J]. Geomorphology, 2007, 85(3/4): 208−224. [20] Guan Bingxian, Fang Guohong. Winter counter-wind currents off the southeastern China coast: a review[J]. Journal of Oceanography, 2006, 62(1): 1−24. doi: 10.1007/s10872-006-0028-8 [21] Yuan Dongliang, Zhu Jianrong, Li Chunyan, et al. Cross-shelf circulation in the Yellow and East China Seas indicated by MODIS satellite observations[J]. Journal of Marine Systems, 2008, 70(1/2): 134−149. [22] 于非, 臧家业, 郭炳火, 等. 黑潮水入侵东海陆架及陆架环流的若干现象[J]. 海洋科学进展, 2002, 20(3): 21−28. doi: 10.3969/j.issn.1671-6647.2002.03.004Yu Fei, Zang Jiaye, Guo Binghuo, et al. Some phenomena of the Kuroshio intrusion into shelf area and the shelf circulation of the East China Sea[J]. Advances in Marine Science, 2002, 20(3): 21−28. doi: 10.3969/j.issn.1671-6647.2002.03.004 [23] Xu Kehui, Milliman J D, Li Anchun, et al. Yangtze- and Taiwan-derived sediments on the inner shelf of East China Sea[J]. Continental Shelf Research, 2009, 29(18): 2240−2256. doi: 10.1016/j.csr.2009.08.017 [24] 刘世东, 乔璐璐, 李广雪, 等. 东海内陆架悬浮体输运、通量及季节变化[J]. 海洋与湖沼, 2018, 49(1): 24−39.Liu Shidong, Qiao Lulu, Li Guangxue, et al. Transport and flux of suspended sediment and its seasonal variation over the inner shelf of the East China Sea[J]. Oceanologia et Limnologia Sinica, 2018, 49(1): 24−39. [25] Goldberg E D, Koide M. Rates of sediment accumulation in the Indian Ocean[M]//Earth Science and Meteoritics. Amsterdam: North-Holland Publishing Company, 1963: 90−102. [26] 李帅, 杨胜利, 梁敏豪, 等. 青藏高原东部黄土粒度分布的端元模型研究[J]. 地球与环境, 2018, 46(4): 331−338.Li Shuai, Yang Shengli, Liang Minhao, et al. The end member model analysis on grain size of loess in the Eastern Tibetan Plateau[J]. Earth and Environment, 2018, 46(4): 331−338. [27] Gao Jianhua, Jia Jianjun, Sheng Hui, et al. Variations in the transport, distribution, and budget of 210Pb in sediment over the estuarine and inner shelf areas of the East China Sea due to Changjiang catchment changes[J]. Journal of Geophysical Research: Earth Surface, 2017, 122(1): 235−247. doi: 10.1002/2016JF004130 [28] 张晓东, 季阳, 杨作升, 等. 南黄海表层沉积物粒度端元反演及其对沉积动力环境的指示意义[J]. 中国科学: 地球科学, 2016, 59(2): 258−267. doi: 10.1007/s11430-015-5165-8Zhang Xiaodong, Ji Yang, Yang Zuosheng, et al. End member inversion of surface sediment grain size in the South Yellow Sea and its implications for dynamic sedimentary environments[J]. Science China Earth Sciences, 2016, 59(2): 258−267. doi: 10.1007/s11430-015-5165-8 [29] 杨作升, 郭志刚, 王兆祥, 等. 黄东海陆架悬浮体向其东部深海区输送的宏观格局[J]. 海洋学报, 1992, 14(2): 81−90.Yang Zuosheng, Guo Zhigang, Wang Zhaoxiang, et al. Basic pattern of transport of suspended matter from the Yellow Sea and East China Sea to the eastern deep seas[J]. Haiyang Xuebao, 1992, 14(2): 81−90. [30] 郭志刚, 杨作升, 张东奇, 等. 冬、夏季东海北部悬浮体分布及海流对悬浮体输运的阻隔作用[J]. 海洋学报, 2002, 24(5): 71−80.Guo Zhigang, Yang Zuosheng, Zhang Dongqi, et al. Seasonal distribution of suspended matter in the northern East China Sea and barrier effect of current circulation on its transport[J]. Haiyang Xuebao, 2002, 24(5): 71−80. [31] 范德江, 杨作升, 孙效功, 等. 东海陆架北部长江、黄河沉积物影响范围的定量估算[J]. 青岛海洋大学学报, 2002, 32(5): 748−756.Fan Dejiang, Yang Zuosheng, Sun Xiaogong, et al. Quantitative evaluation of sediment provenance on the north area of the East China Sea Shelf[J]. Journal of Ocean University of Qingdao, 2002, 32(5): 748−756. [32] Li Congxian, Chen Gang, Yao Ming, et al. The influences of suspended load on the sedimentation in the coastal zones and continental shelves of China[J]. Marine Geology, 1991, 96(3/4): 341−352. [33] Liu J P, Liu C S, Xu K H, et al. Flux and fate of small mountainous rivers derived sediments into the Taiwan Strait[J]. Marine Geology, 2008, 256(1/4): 65−76. [34] 李家彪. 东海区域地质[M]. 北京: 海洋出版社, 2008.Li Jiabiao. Regional Geology of the East China Sea[M]. Beijing: China Ocean Press, 2008. [35] 曾定勇, 倪晓波, 黄大吉. 冬季浙闽沿岸流与台湾暖流在浙南海域的时空变化[J]. 中国科学: 地球科学, 2012, 42(7): 1123−1134. doi: 10.1360/zd-2012-42-7-1123Zeng Dingyong, Ni Xiaobo, Huang Daji. Temporal and spatial variability of the ZheMin Coastal Current and the Taiwan Warm Current in winter in the southern Zhejiang coastal sea[J]. Science Sinica Terrae, 2012, 42(7): 1123−1134. doi: 10.1360/zd-2012-42-7-1123 [36] 阮美娜, 李炎, 陈一宁, 等. 夏季台湾海峡的悬浮颗粒通道: 现场粒度端元分析的证据[J]. 科学通报, 2012, 57(36): 3522−3532. doi: 10.1360/972012-429Ruan Meina, Li Yan, Chen Yining, et al. Summer pathways for suspended particles across the Taiwan Strait: evidence from the end-member analysis of in-situ particle size[J]. Chinese Science Bulletin, 2012, 57(36): 3522−3532. doi: 10.1360/972012-429 [37] Milliman J D, Lin S W, Kao S J, et al. Short-term changes in seafloor character due to flood-derived hyperpycnal discharge: typhoon Mindulle, Taiwan, July 2004[J]. Geology, 2007, 35(9): 779−782. doi: 10.1130/G23760A.1 [38] Kao S J, Milliman J D. Water and sediment discharge from small mountainous rivers, Taiwan: the roles of lithology, episodic events, and human activities[J]. The Journal of Geology, 2008, 116(5): 431−448. doi: 10.1086/590921 [39] Tian Yuan, Fan Dejiang, Zhang Xilin, et al. Event deposits of intense typhoons in the muddy wedge of the East China Sea over the past 150 years[J]. Marine Geology, 2019, 410: 109−121. doi: 10.1016/j.margeo.2018.12.010 [40] 李长安, 张玉芬, 袁胜元, 等. 江汉平原洪水沉积物的粒度特征及环境意义——以2005年汉江大洪水为例[J]. 第四纪研究, 2009, 29(2): 276−281. doi: 10.3969/j.issn.1001-7410.2009.02.11Li Chang’an, Zhang Yufen, Yuan Shengyuan, et al. Grain size characteristics and environmental significance of Hanjiang 2005 flood sediments[J]. Quaternary Sciences, 2009, 29(2): 276−281. doi: 10.3969/j.issn.1001-7410.2009.02.11 [41] Gao Juanhua, Shi Yong, Sheng Hui, et al. Rapid response of the Changjiang (Yangtze) River and East China Sea source-to-sink conveying system to human induced catchment perturbations[J]. Marine Geology, 2019, 414: 1−17. doi: 10.1016/j.margeo.2019.05.003 [42] 万世明, 李安春, Stuut J B W, 等. 南海北部ODP1146站粒度揭示的近20 Ma以来东亚季风演化[J]. 中国科学D辑: 地球科学, 2007, 37(6): 761−770.Wan Shiming, Li Anchun, Stuut J B W, et al. The evolution of East Asian monsoon since nearly 20 Ma revealed from granularity of ODP1146 station in the north of the South China Sea[J]. Science in China Series D: Earth Science, 2007, 37(6): 761−770. [43] 肖尚斌, 李安春. 东海内陆架泥区沉积物的环境敏感粒度组分[J]. 沉积学报, 2005, 23(1): 122−129. doi: 10.3969/j.issn.1000-0550.2005.01.016Xiao Shangbin, Li Anchun. A study on environmentally sensitive grain-size population in inner shelf of the East China Sea[J]. Acta Sedimentologica Sinica, 2005, 23(1): 122−129. doi: 10.3969/j.issn.1000-0550.2005.01.016 [44] 郑洪波, 陈国成, 谢昕, 等. 南海晚第四纪陆源沉积: 粒度组成、动力控制及反映的东亚季风演化[J]. 第四纪研究, 2008, 28(3): 414−424. doi: 10.3321/j.issn:1001-7410.2008.03.005Zheng Hongbo, Chen Guocheng, Xie Xin, et al. Grain size distribution and dynamic control of late quaternary terrigenous sediments in the South China Sea and their implication for East Asian monsoon evolution[J]. Quaternary Sciences, 2008, 28(3): 414−424. doi: 10.3321/j.issn:1001-7410.2008.03.005 [45] 石勇, 高建华, 刘强, 等. 陆架环流作用下的北黄海中北部细颗粒物质输运[J]. 海洋学报, 2019, 41(4): 53−63.Shi Yong, Gao Jianhua, Liu Qiang, et al. Fine sediment transport in north-central of Yellow Sea: the role of continental shelf circulation[J]. Haiyang Xuebao, 2019, 41(4): 53−63.