黄河三角洲人工放淤对环境演化的影响

在洪水季节，为使黄河更好地排洪输沙，在黄河三角洲实行人工放淤，通过放淤，使河水分流，减少河水冲垮河堤的危险性，也减少了泥沙淤积量，放淤区新沉淀的泥沙压制了盐碱，并可把盐碱地改造成为良田。     

南四湖区泥沙淤积分析

根据南四湖区各主要入湖河流径流泥沙资料，分析了河流泥沙要素变化规律以及入湖泥沙淤积情况，对掌握和了解流域水土流失状况，进行流域治理，加强生态环境建设具有一定的指导意义。     

黄河下游泥沙输沙率的预测

利用黄河利津站的精密水文泥沙测量结果对一些常用水流泥沙输沙率公式进行验证表明，Ｖａｎ Ｒｉｊｎ公式最适合于黄河泥沙输沙率的预测，对公式做部分校正则可以大大提高其预测能力。     

关于登州浅滩作用的研究

１９９０－１９９３年对蓬莱西庄海岸附近海域进行了水文、水深、地质地貌和泥沙等１３项测量和调查。整理分析实测资料并结合数值计算，首次分析研究了登州浅滩的作用并着论述了浅滩被破坏后袭击岸边的波浪增大，波能增中到５－７倍，沿岸输沙量增中到３－５倍。文中指出西庄海岸侵蚀加剧的主要原因是，登州浅滩被破坏后失去防浪消波作用而造成的。     

黄河三角洲埕岛近岸海域悬浮泥沙运动

根据1998年9月8日和1999年3月19日两次对埕北海域进行的10个站位的同步海流、悬浮泥沙观测资料，进行该海区的悬浮泥沙输运趋势分析，发现该海区含沙量较大。从整个海区来看，底层含沙量大于表层含沙量，该海区泥沙含量普遍表现为东南部的泥沙含量高于西北部的泥沙含量；由单宽输沙量的计算及有关资料分析可以得出，秋季泥沙运移趋势是由东南向到西北向，而春季泥沙的运移趋势是由东北向到西南向；含沙量是随流速的加大而增加，含沙量的峰值稍滞后于流速的峰值；该海区为冲蚀海区，悬浮泥沙产生的平均年7中刷量为2cm／a，在本海区的地形塑造中占次要地位。     

渤海海流概况及其输沙作用初析

本文讨论了渤海及黄河口附近海域的海洋动力状况，潮流和风暴急流是输送黄河入海泥沙的主要动力。     

渤海海流概况及其输沙作用初析

本文讨论了渤海及黄河口附近海域的海洋动力状况，潮流和风暴急流是输送黄河入海泥沙的主要动力。     

应用现场实测波浪资料直接计算沿岸输沙率

本文应用波能流守恒法则，导得可直接应用现场实测波浪资料计算沿岸输沙率关系式。通过两个实例计算，说明计算值与实际沿岸输沙率一致。     

砂质海岸岸滩侵蚀演变模式探讨——以山东南部海岸侵蚀岸段的岸滩演变为例

在分析山东南部海岸几十年来的地形观测资料的基础上，运用砂质海岸等深线变化预测理论，建立该区的岸滩侵蚀演变预测模型，研究了该区域岸滩演变规律。实测资料验证表明：预测结果合理，基本反映了本区岸滩演变的特征。     

舟山螺头水道悬沙数值模拟研究

建立了以舟山螺头水道海域为重点研究区域的平面二维潮流泥沙数学模型,模型对螺头水道海域2005年1月的悬沙场进行了模拟,将模拟结果与实测资料进行比较,二者吻合较好,模拟结果分析表明:螺头水道内含沙量由西至东逐渐减小,涨落潮主流流路的差异使得水道内存在两股相反的悬沙净输运趋势,但总体净输沙方向为落潮流方向;含沙量与涨落潮流过程密切相关,水道内以平流输沙作用为主,沉降及再悬浮作用小,是长江口及杭州湾向外海输沙的主要通道而非主要沉积区域.     

Numerical simulation and satellite observations of suspended matterin the North Sea

Two methods for the investigation of suspended particulate matter (SPM) transport in the North Sea are presented: numerical modeling and remote sensing by satellite. The principles and the main components of the two methods are outlined. The numerical model uses a particle tracer method for the simulation of advective transport. It takes into account the interaction with the sediment bed (deposition, erosion). Remote sensing uses data of the Coastal Zone Colour Scanner (CZCS). The physical background of remote sensing is outlined and an inverse modeling procedure for evaluation of the satellite images is described. Data obtained with the two methods are compared with each other and with ship measured data which shows the strong and the weak points of each method. The combined use of field measurements, satellite observations, numerical modeling and specific in situ process studies is recommended as the most effective way to investigate SPM transport     

Nonuniform sediment transport under non-breaking waves and currents

Empirical formulas have been developed to calculate the fractional bed-load and suspended-load transport rates and near-bed suspended-load concentration under non-breaking waves and currents for coastal applications. The formulas relate the bed-load transport rate to the grain shear stress, the suspended-load transport rate to the energy of the flow system, and the near-bed suspended-load concentration to the bed-load transport rate, velocity and layer thickness. Adequate methods are adopted to determine the bed shear stress due to coexisted waves and currents. The hiding and exposure mechanism in nonuniform bed material is considered through a correction factor that is related to the hiding and exposure probabilities and in turn the size composition of bed material. The developed formulas have been tested using a large database of single-sized sediment transport and several sets of multiple-sized sediment transport data collected from literature, and compared with several existing formulas. The developed formulas can provide reasonably good predictions for the test cases.     

沙质海岸沿岸输沙率计算方法研究进展

准确预测波浪作用下沿岸输沙率是沙质海岸研究领域的重要科学问题。根据数十年来国内外沿岸输沙率公式的研究进展,按研究方法对各项成果进行分类,并兼顾时间逻辑,回顾了各研究方法的发展历程及其代表性成果。对各项成果的理论基础、考虑因素、资料来源等方面进行了探讨,并采用现场原型沙、室内原型沙和室内轻质沙等实测资料,对国内外常用公式的预测准确性进行了检验。结果表明,孙林云公式与各项实测资料的吻合程度最高,在众多沿岸输沙率公式中具有明显的先进性。在此基础上,对未来可进一步深化研究的方向作出了展望。     

Longshore sediment transport estimation using a fuzzy inference system

Accurate prediction of longshore sediment transport in the nearshore zone is essential for control of shoreline erosion and beach evolution. In this paper, a hybrid Adaptive-Network-Based Fuzzy Inference System (ANFIS), Fuzzy Inference System (FIS), CERC, Walton–Bruno (WB) and Van Rijn (VR) formulae are used to predict and model longshore sediment transport in the surf zone. The architecture of ANFIS consisted of three inputs (breaking wave height), (breaking angle), (wave period) and one output (longshore sediment transport rate). For statistical comparison of predicted and measured sediment transport, bias, root mean square error and scatter index are used. The longshore sediment transport rate (LSTR) and wave characteristics at a 4 km-long beach on the central west coast of India are used as case studies. The CERC, WB and VR methods are also applied to the same data. Results indicate that the errors of the ANFIS model in predicting wave parameters are less than those of the empirical formulas. The scatter index of the CERC, WB and VR methods in predicting LSTR is 51.9%, 27.9% and 22.5%, respectively, while the scatter index of the ANFIS model in the prediction of LSTR is 17.32%. A comparison of results reveals that the ANFIS model provides higher accuracy and reliability for LSTR estimation than the other techniques.     

Transport rate under irregular sheet flow conditions

This paper presents the results of experiments conducted on sand transport in sheet flow conditions under nonlinear asymmetric irregular oscillations with different frequency spectrums. Two methods are proposed for estimation of the transport rate. The first method which is based on a wave by wave analysis of the irregular velocity profile gives very accurate predictions. The second method, which uses a representative single wave, is less computing time consuming and still gives satisfactory results. The measured net transport rates do not show any dependence on the spectral shape.     

A Comprehensive Lagrangian Transport Study in A Long-Narrow Bay,Xiangshan Bay,China

Study on the transport and mixing in coastal waters is of great concern to the ocean resources exploitation and ecological system protection. Lagrangian methods are direct and effective of researching mass transport. Two Lagrangian tools were adopted and combined to describe water transport in a long-narrow bay, Xiangshan Bay,China. Based on the fields of tidal velocity simulated from the 3-D hydrodynamic model, Lagrangian Coherent Structures(LCSs) and synoptic Lagrangian maps(SLMs) were calculated in the study area. Through comparison of the results, the features and relation of the two tools were discussed. The results show that the LCSs act as the separatrix of the water regions with different transport characteristics and can identify the water areas with different transport time scales. The comprehensive application of the Lagrangian tools is helpful to obtain more insight into the water transport process.     

Numerical Simulation of Local Scour Around A Large Circular Cylinder Under Wave Action

A horizontal two- dimensional numerical model is developed for estimation of sediment transport and sea bed change around a large circular cylinder under wave action. The wave model is based on an elliptic mild slope equation. The wave-induced current by the gradient of radiation stress is considered and a depth integrated shallow water equation is applied to the calculation of the current. The mass transport velocity and the bed shear stress due to streaming are considered, which are important factors affecting the sediment transport around a structure due to waves, especially in reflective areas. Wave-current interaction is taken into account in the model for computing the bed shear stress. The model is implemented by a finite element method. The results of this model are compared with those from other methods and agree well with experimental data.     

Contaminant transport modeling in marine clays

The need to develop various offshore containment systems encourages the contaminant transport study in marine clays. In the present investigation, an attempt has been made to examine six cases of contaminant transport in marine clays. Adequate literature background on the chemical diffusion of soils, and the earlier reported modeling techniques relevant to the present work have been highlighted. These methods enable a rapid examination of the impact of contaminant physical properties on the environment over a period of time. The numerical results of this study help to understand the chemicals transport phenomena in the marine environment especially at sea bed.     

Numerical experiments on estimating the accuracy of the methods of solution of the Kalman smoothing problems

The model numerical experiments on estimating the accuracy of two methods for solving the problem of Kalman smoothing, both iteration and precise, are described on the basis of a simple equation for the passive admixture transport. Some quantitative estimations are given.Translated by Mikhail M. Trufanov.     

Multitrack surveying of large bedforms

Data are presented from multitrack surveys of large, sandy bedforms in the Fraser River estuary, Canada. A detailed contour map and block diagram provide information on three-dimensional bedform geometry that could not be obtained using conventional survey methods. The technique has implications for estimation of bedload transport and for bedform classification.