潮汐河口断面悬沙通量组分模式及其在长江口的应用  

Fractional model of crosssectional suspended sediment flux and its application in the Changjiang (Yangtze) Estuary

作　　者：吴加学[1] 沈焕庭[2] 吴华林[2] 

机构地区：[1]同济大学海洋地质教育部重点实验室,上海200092 [2]华东师范大学河口海岸国家重点实验室,上海200062

出　　处：《海洋学报》2002年第6期49-58,共10页

基　　金：国家自然科学基金重点项目"长江河口通量研究"资助项目(49736220).

摘　　要：断面泥沙通量估算的误差主要来源于计算方法、测点布局等,通量模式应该建立在通量估算统计误差最小的原则基础之上.在断面网格设计中采用统计误差最小的等面积单元网格,在泥沙通量估算中采用泥沙组分浓度,在流速变量插值上垂向采用对数函数插值,横向采用第一边界三次方样条函数插值.这样建立的潮汐河口悬沙断面通量组分模式较以往的任何模式更完善,断面通量估算的误差最小.将该模式应用于长江河口南港断面悬沙通量估算及其输移机制分析,断面泥沙通量表现为大潮期大进大出、大出大于大进;小潮期小进小出、小出大于小进;主要输移机制是拉格朗日输移和潮泵.The errors of the crosssectional sediment flux estimation mainly origin from survey site layout and flux calculation method. The flux model should copy with the principle of the minimum statistical errors of flux estimation. A grid with equal cell area is designed since only this type of grid introduces the fewest statistical errors in the flux estimation. Considering the sediment of different grainsizes has different properties and transport behaviors, fractional concentration of suspended sediment is taken to estimate the various fractional fluxes. Vertical interpolation of the variables takes a logarithmic method and horizontal interpolation takes a cubic spline method. The crosssectional fractional flux model of suspended sediment in a tidal estuary is further developed and applied to the estimation of fractional sediment fluxes and sediment transport mechanism in the Changjiang Estuary The crosssectional sediment fluxes in the spring tide are characterized by larger inwards and larger outwards transportations with the latter being larger than the former, while sediment fluxes in the neap are characterized by smaller inwards and smaller outwards transports with the latter being larger than the former The principal transport mechanisms of residual fluxes are Lagrangian transport and tidal pumping. 

关 键 词：断面悬沙通量 泥沙通量 潮汐河口 长江河口 营养元素 悬移质 

分 类 号：TV148.1[水利工程—水力学及河流动力学]