sediment size

Errors analysis of testing sediment grain size by the methods of laser way and extinction sedimentation way

激光法与消光沉降法测试泥沙粒径误差分析

By the analysis of theory, the research elaborates that the threshold condition for incipient motion of non-uniform sediment with a specific size, is directly related to flow condition, sediment size distribution, location of bed material, and income sediment from upstream.

本项研究从理论上论述了非均匀沙某级粒径的临界可动条件不仅与水流条件有关，也与泥沙级配组成有关，还与床沙位置、上游来沙条件有密切的关系。

The sediment size changes sharply in two reaches of the middle and lower Yangtze River. Sediment type changes from gravel into sand in one zone, and another from sand into mud.

长江中下游河床沉积物在两个河段出现了粒径的急剧变化和沉积物类型的转换，一个是从砾石转变为砂，另一个是从砂转变为泥。

But from the Yangtze Estuary to the southern of the study area, the sediment grain size shows an exponential fining trend. ( 2) Two abrupt transition zone of the grain size in downstream of TGD and the estuary.

而从长江口至研究海区最南面，沉积物粒径又表现出呈指数细化的特征。（2）三峡大坝下游和长江河口的两个粒径突变带。

The sharp decrease of sediment discharge results in the serious erosion of the riverbed downstream the TGD and the sediment grain size show obvious coarsening.

输沙量的急剧减少，导致三峡大坝下游河床出现了严重的侵蚀，沉积物粒径出现明显粗化。

Grain-size Variations of Terrigenous Sediment Sequences in the South Okinawa Trough

冲绳海槽南部沉积层序的粒度特征

Experimental Study on Transport Rate of Non uniform Sediment with Wide Size Distribution

宽级配非均匀推移质输沙率的实验研究

The contents of different forms of nitrogen and phosphorus in different sites were mainly influenced by terrigenous inputs, sediment grain size and hydro-dynamics.

在平面分布上，各站间不同形态氮、磷的含量差异与陆源输入、沉积物粒径及水动力条件等因素有关。

The vertical variation of Hg contents in the relic site strata are related to the regional human activities, climate conditions, vegetation status and sediment grain size, namely the regional natural environment evolution.

同时发现，汞含量在地层中呈垂直波动变化，这反映了该地区人类生产活动、气候条件、植被状况和剖面沉积物粒度大小等的影响，即与该地区人类活动以及自然环境演变有相当关系。

If the wave condition is same, with the increasing of sediment size, the scour and deposition patterns can be classified into DSD type, SDSD type and DSDS type.

在相同波浪条件下，随着泥沙相对粒径的由细变粗，堤前冲淤形态可分为DSD型、SDSD型和DSDS型。

It shows that the sediment transporting capacity not only is related to the particle size of sediment, but also mainly depends on the slope and coefficient of fluvial facies.

从公式可以看出，输沙能力的大小，除与泥沙粗细有关外，主要决定于坡降和河相系数。