杭州湾北部潮流深槽区细颗粒物质输运与再悬浮过程

杨旸; 高抒; 汪亚平

杭州湾北部潮流深槽区细颗粒物质输运与再悬浮过程

南京大学海岸与海岛开发教育部重点实验室, 江苏, 南京, 210093

基金项目: 国家自然科学基金重点资助项目(40231010)

计量
- 文章访问数: 827
- HTML全文浏览量: 4
- PDF下载量: 1175
- 被引次数: 0
出版历程
- 收稿日期: 2007-05-23
- 修回日期: 2007-10-17

Fine-grained sediment transport and resuspension process in a tidal channel of the northern Hangzhou Bay in China

Key Laboratory of Ministry of Education for Coast and Island Development, Nanjing University, Nanjing 210093, China

摘要

摘要: 于2005年5月大潮期间在杭州湾北部潮流深槽区的4个站位进行潮周期观测,获得了流速、悬沙等数据,并对其进行了分析,计算了水沙通量和再悬浮通量。分析结果表明,该深槽区涨潮流速大于落潮流速,涨潮历时小于落潮历时,潮差自湾口向湾内方向增大;悬沙的组分以粉砂为主,分选较差,偏态以负偏为主,这些特征与底质一致;深槽中部和东部的悬沙沿岸线向湾内方向输运;深槽西部和东部外侧的悬沙输运方向与余流方向一致,分别向湾内和南部输运;除转流和流速加速初期外,垂线流速分布符合Kûrmûn-Prandtl模型,摩阻流速与垂线平均流速变化趋势一致。计算得到的表观粗糙长度在涨落潮时段的水流加速或减速阶段都呈增大趋势,且数值较大,这难以把它简单地归结为床面形态的作用,表观粗糙长度的变化趋势可能是高悬沙浓度和浓度成层性共同作用的结果,但对这一假说的验证还有待于进一步的现场观测和机制分析。计算所得的再悬浮发生的周期性与实测悬沙浓度的周期性相符,而且最大悬沙浓度的出现滞后于最大再悬浮通量,说明再悬浮作用对水层中悬沙浓度的变化具有重要影响。
- 悬沙输运 /
- 再悬浮 /
- 边界层过程 /
- 潮流深槽 /
- 杭州湾
Abstract: Tidal cycle measurements of current velocities and suspended sediment concentrations were carried out at four stations in a tidal channel(Jinshan Channel)in the northern Hangzhou Bay in China during a spring tide period in May 2005,together with water and seabed sediment sampling.Data sets were analyzed to obtain suspended sediment transport rates and resuspension fluxes.The results show that the tidal channel is dominated at the flood stage,with at idalrange increasing from the bay mouth tow ards the bay-head areas.The suspended sediment consists mainly of silts,poorly sorted and mostly negatively skewed, being consistent with the bed matter.In the central part of the channel,the net sediment transport direction which directs tow ards the bayhead differs from the residual current direction.In the other parts,the two directions are consistent,being directed tow ards the south in the east and tow ards the bay head in the west.Except for the slack water stage,the vertical distribution patterns of current speed can be described by the Kûrmûn-Prandtl model,with the calculated shear velocity having a similar trend to the vertically averaged current velocity.At most stations,the calculated apparent roughness length show satrend of increase from the beginning of flow acceleration to the end of flow deceleration during both flood and ebbphases of the tide,with extremely large values.Such a pattern cannot be explained by form drag alone;it may be result from a combined effect of high suspended sediment concentration and stratification due to vertical concentration differences within the water column.Further observations and analyses of the associated mechanisms are required to examinet his hypothesis.It is shown that the occurrence of resuspension and the measured suspended sediment concentrations have the same periodicity and the maximum concentration lags behind the maximum resuspension flux,indicating that the resuspension process represents animportant factor controlling the concentration within the water column.
- suspended sediment transport /
- resuspension /
- boundary layer processes /
- tidal channels /
- Hangzhou Bay in China

HTML全文

参考文献(46)

陈吉余,陈沈良,丁平兴.等.长江口南汇咀近岸水域泥沙输移途径[J].长江流域资源与环境,2001.10(2):166-172.

林承坤.长江口泥沙的来源分析与数量计算[J].泥沙研究,1984(2):22-32.

林承坤.长江口泥沙的来源分析与数量计算的研究[J].地理学报,1989,44(1):22-31.

曹沛奎,谷国传,董永发,等.杭州湾泥沙运移的基本特征[J].华东师范大学学报(自然科学版),1985(3);75-84.

沈焕庭,李九发,朱慧芳,等.长江河口悬沙输移特征[J].泥沙研究,1986(3):1-13.

汪亚平,潘少明,WANG Harry,等.长江口水沙人海通量的观测与分析[J].地理学报,2006,61(1);35-46.

周晓静,高抒.底质粒度信息的空间分异与代表性:以杭州湾舟山岛-金山卫断面为例[J].科学通报,2004,49(21):2228-2232.

夏小明,杨辉,李炎,等.长江口-杭州湾毗邻海区的现代沉积速率[J].沉积学报,2004,22(1):130-135.

陈沈良.杭州湾口南汇咀近岸水域水沙特征与通量[J].海洋科学,2004,28(3);18-22.

时钟.杭州湾深水航道浮泥的观测[J].海洋通报,2001,20(6):40-50.

茅志昌,潘定安,沈焕庭.长江河口悬沙的运动方式与沉积形态特征分析[J].地理研究,2001,20(2):170-177.

LAND J M,KIRBY R,MASSEY J B.Developments in the combined use of acoustic Doppler current profilers and profiling siltmeers for suspended solids monitoring[M]//BURT N,PARKER R,WATTS J,ed.Cohesive Sediments.New York:John Wiley &Sons,1997 187-196.

HAMILTON L J,SHI Zhong,ZHANG Shu-yi,Acoustic backscatter measurements of estuarine suspended cohesive sediment concentration profiles[J].Journal ot Coastal Research,1998,14(4):1213-1224.

HOLDAWAY G P,THORNE P D,FLATT D,et al.Comparison between ADCP and transmissometer measurements of suspended sediment concentration[J].Continental Shelf Research,1999,19,421-441.

程鹏,高抒.ADCP测量悬沙浓度的可行性分析与现场标定[J].海洋与湖沼,2001,32(2):168-176.

SHI Zhong,REN Lai-fa,LIN Hui-tian.Vertical suspension profile in the Changjiang Estuary[J].Marine Geology,1996,130:72-81.

SHI Zhong,REN Lai-fa,ZHANG Shu-yi,et al.Acoustic imaging ot cohesive sediment resuspension and re-entrainment in the Changjiang Estuary,East China Sea[J].Geo-Marine Letters,1997,17:162-168.

汪亚平,高抒,李坤业.用ADCP进行走航式悬沙浓度测量的初步研究[J].海洋与湖沼,1999,30(6):758-763.

高建华,汪亚平,王爱军,等.ADCP在长江口悬沙输运观测中的应用[J].地理研究,2004,23(4);455-462.

李身铎,胡辉.杭州湾流场的研究[J].海洋与湖沼,1987,18(1):28-38.

曹沛奎,董永发,周月琴.杭州湾北部潮流冲刷槽演变的分析[J].地理学报,1989,44(2):157-166.

刘苍字,董永发.杭州湾的沉积结构与沉积环境分析[J].海洋地质与第四纪地质,1990,10(4):53-65.

刘阿成.杭州湾金山深槽的地貌特征及其控制因素[J].海洋通报,1992,11(5):71-77.

余祈文,符宁平.杭州湾北岸深槽形成及演变特性研究[J].海洋学报,1994,16(3):74-85.

汪亚平,高建华.河口海岸区悬沙输运量的声学多普勒流速剖面(ADCP)观测技术的初步研究[J].科学技术与工程,2003,3(5):467-470.

贾建军,高抒,薛允传.图解法与矩法沉积物粒度参数的对比[J].海洋与湖沼,2002,33(6):576-582.

THEVENOT M M,KRAUS N C.Comparison of acoustical and optical measurements of suspended material in the Chesapeake Estuary[J].Journal of Marine Environment Engineering,1993(1):65-79.

WANG Ya-ping,CHU Yong Shik,LEE Hee Jun,et al.Estimation of suspended sediment flux from acoustic Doppler current profiling along the Jinhae Bay entrance[J].Acta Oceanologica Sinica,2005,24(2):16-27.

刘红,何青,孟翊,等.长江口表层沉积物分布特征及动力响应[J].地理学报,2007,62(I);81-92.

DYER K R.Coastal and Estuarine Sediment Dynamics[M].Chichester:Wiley,1986..50,62.

WANG Ya-ping,GAO Shu,XIANKUN K E.Measurements of boundary layer parameters and suspended sediment transport over the intertidal flats of northern Jiangsu,China[J].Acta Oceanologica Sinica,2004,23(3):437-448.

PARTHENIADS E.Erosion and deposition of cohesive soil[J].Journal of the Hydraulics Division,ASCE,1965,91 (HY1):105-139.

KRONE R B.Flume studies of the transport of sediment in estuarial shoaling processes.Final Report[R]//Hydrologieal Engineering Laboratory and Sanitary Engineering Research Laboratory.Berkeley:University of California,1962t110-112.

SOULSBY R.Dynamics of marine sands[M]//A Manual for Practical Applications.London:Thomas Telford Publication,1997:104-107.

JIA Jian-jun,GAO Shu,XUE Yun-chuan.Sediment dynamic processes of the Yuehu inlet system,Shandong Peninsula,China[J].Estuarine,Coastal and Shelf Science,2003,57:783-801.

SOULSBY R.The bottom boundary layer of shelf seas[M]//JOHNS B,ed.Physical Oceanography of Coastal and Shelf Seas.1983:189-266.

CHENG R T,LING C H,GARTNER J W,et al.Estimates of bottom roughness length and bottom shear stress in South San Francisco Bay,California[J].Journal of Geophysical Research[J].1999.104:7715-7728.

LI Yan,GAO Shu,WANG Zheng-fang,et al.Settling velocity of fine sediments in estuarine environment[C]//YU Guo-hui,MARTIN J-M,ZHOU Jia-yi,eds.Biogeochemistry Study of the Changjiang Estuary.Beijing:China Ocean Press,1990:99-109.

冯应俊,李炎,谢钦春,等.杭州湾地貌及沉积界面的活动性[J].海洋学报,1990,12(2):213-223.

陈吉余,罗祖德,陈德昌,等.钱塘江河口沙坎的形成及其历史演变[J].地理学报,1964,30(2):109-122.

高抒,张立人.金塘水道潮流一悬沙相关性及其与再悬浮作用的关系[J].海洋通报,1989,8(4):51-58.

李占海,高抒,沈焕庭.金塘永道的悬沙输运和再悬浮作用特征[J].泥沙研究,2006(3):55-62.

GUST O.Observations on turbulent-drag reduction in a dilute suspension of clay in sea-water[J].Journal of Fluid Mechanics,1976,75 (1):29-47.

VINZON S B,METHA A J.Boundary layer effects due to suspended sediment transport in the Amazon River estuary[M]//MCANALLY W H,MEHTA A J,eds.Coastal and Estuarine Fine Sediment Processes.Amsterdam:Elsevier,2001:359-372.

ADAMS C E,WEATHERLY G L.Some effects of sediment stratification on an oceanic bottom boundary layer[J].Journal of Geophysical Research,1981,86(C5):4161-4172.

SHENG Y P,VILLARET C.Modeling the effect of suspended sediment stratification on bottom exchange processes[J].Journal of Geophysical Research,1989,94(C10):14429-14444.

施引文献

资源附件(0)

访问统计