The quantity of sand fraction sediment in reservoirs as the basis of an assessment of the bedload transport from a reservoir catchment     

Szczepan Ludwik Dąbkowski  Łukasz Bąk 《国际泥沙研究》2018,33(4):385-394

A knowledge of the quantity of the sand fraction in the sediments deposited in reservoirs makes it easier to determine the bedload transport, which is a rarely measured parameter. The current study discusses the results of investigations into the siltation and physical properties of sediment in two small reservoirs located in the southeastern part of Poland. Also, the quantity of the bedload sand fraction was estimated.The estimation of the reservoir capacity loss after t years of operation was based on hydroacoustic measurements. The sediment density, organic matter content, and granulometric composition were evaluated by means of investigations and analyses of bottom sediment core samples. The interpolation of the parameters describing the sediment properties was done using the Kriging method. The analyses indicate that 10.80 thousand m~3 of sediment were deposited into the Zalew Kielecki Reservoir in the years 2004-2015. Their overall mass was 7320 t, of which sand fraction sediments constituted 39.7%.Between the years 2004 and 2014, the Umer Reservoir retained 11.79 thousand m~3 of sediment having a mass of 7200 t, of which sand fraction constituted 34.6%.  相似文献   

The morphodynamic responses to deposition-promoting projects in island and reef coasts of the Zhoushan Archipelago,China     

Qingzhi Hou  Zhili Wang  Yongjun Lu  Siping Mo 《国际泥沙研究》2017,32(3)

China's island and reef coasts are mainly distributed along the coasts of Zhejiang and Fujian provinces. These areas have favorable deep-water conditions and great development potential. The Zhoushan Archipelago is a typical island and reef coast. In the midst of the islands, there are many tidal channels with high water depth and high current velocity. Daishan Island is located on the northern part of the Zhoushan Archipelago. The sea north of Daishan Island can be characterized as having great water depth (generally between 10 and 20 m), high current velocity (the maximum measured value is about 2 m/s), and hyperconcentrated suspended sediment (annual average concentration under normal weather conditions is about 0.6 kg/m3). Sediment transport is influenced by the co-action of waves and currents. Land reclamation can ease the contradiction between the desire for development and the land resource shortage on island and reef coasts. Land reclamation generally starts from deposition-promoting projects on island and reef coasts with hyperconcentration of suspended sediment with the aim of reducing the reclamation cost. Based on the morphodynamic characteristics of the sea area near north of Daishan Island, a two-dimensional mathematical model was developed to analyze the co-action of current and waves and the model was verified for spring as well as neap tides in 2007 and 2012. The simulated values of tidal stages, tidal current velocities, tidal current directions, and suspended sediment concentration at 15 stations in 2007 and 9 stations in 2012 were in good agreement with the in-situ measured values. Furthermore, the simulated magnitude and pattern of erosion and sedimentation agreed well with the observations. This model was used to evaluate the effects of a proposed siltation scheme on the hydrodynamic environment and morphological change of the study area. The results of this study can inform the protection, development, and utilization of shoal-channels on island and reef coasts, as well provide a scientific basis for comprehensive maritime protection and development.  相似文献   

1976年黄河改道以来三角洲近岸区变化遥感监测   总被引：17，自引：1，他引：16  

黄海军  樊辉 《海洋与湖沼》2004,35(4):306-314

通过对黄河三角洲沿岸10个河口、潮汐汉道的23景陆地卫星影像高潮线的解译与对比,探讨自1976年黄河改道以来,三角洲岸线的变化特征;同时,利用GIS软件处理1976年和1992年滨海区水深测量数据,并与黄河利津站同期入海沙量进行对照分析。结果表明：1)目前黄河三角洲总体处于侵蚀破坏阶段,侵蚀岸线长相当于淤积岸线的2倍;2)人类活动对三角洲岸线变化的影响不断增强,人工海岸长度大幅度增加,总岸线长度缩短,岸线趋于平直;3)52．6％的黄河入海泥沙堆积于入海口附近,其中92％的泥沙堆积在15m水深线以内,向外迅速减少,20m水深线以外出现侵蚀;4)87％黄河入海泥沙往东、东南方向扩散与沉积,往南、东北方向扩散与沉积的泥沙很少,河口的北、西北方向整体上处于侵蚀状态。海岸侵蚀与河口泥沙的输移密切相关。  相似文献