Understanding the response of the intertidal dunes to the varying hydrodynamic conditions in mixed wave-tide environments is of high complexity. Field measurement is one of the most useful approaches to investigate the dune dynamics at different time (semi-diurnal and lunar cycles) and spatial (dunes and associated superimposed bedforms) scales. High-resolution laser scanner data for five successive surveys over a full neap-spring cycle (27 January – 9 February 2014), together with hydrodynamic measurements, have been explored to investigate the morphodynamics of dunes, their superimposed bedforms and their migration in a mixed wave-tide environment (case of the Baie de Somme, Eastern of the English Channel), by the use of a stochastic-physical coupling approach. The dunes are ~12 m wavelength, 0.4 height and oriented orthogonally to the shoreline with angles varying between - 45° and + 45° corresponding to clockwise and counter-clockwise changes, respectively.

A stochastic approach, based on spectral analysis, exhibits a series of morphological defects modulating the dune changes following several scale ranges in response to various energy conditions. Such defects can be classified into four categories: (1) limited structures of ~1.6 m wavelengths locally developed along the dune during flood drainage; (2) small-scale superimposed bedforms of ~3.2 m wavelengths built-up across the dunes after high hydrodynamics and proliferated when the energy deceases; (3) large-scale superimposed bedforms of ~6.4 m resulting from the morphological growth of the smaller bedforms; (4) crestline sinuosity with ~25 m wavelength and induced by changes in the orientation of the dunes when they are exposed to high tide-wave activity. The evolving dune defects over the neap-spring cycle is strongly related to the physical mechanisms of sediment transport supplying the migrating dunes and favorable for their self-organization.

The physical study of the migrating dunes with the wave-tide driven sediment transport highlights that the long-dune migration components are significantly important during high-energy episodes with a mean explained variance of 65% of the total migration while they decrease to 32% for moderate wave-tide conditions. Good matches of the cross- and long-migration components with the along-shore and the cross-shore sediment transport quantities are recorded with R² coefficients higher than 70%. These coefficients increase for the offshore dunes where their morphological response to the time-averaged sediment transport is faster while onshore dunes respond at slower timescales resulting in lower R² coefficients.

了解潮汐沙丘对潮汐混合环境中变化的水动力条件的响应非常复杂。野外测量是研究沙丘在不同时间（半日和月球周期）和空间（沙丘和相关叠加的床形）尺度的动态的最有用的方法之一。已探索了在整个小泉周期（2014年1月27日至2月9日）中进行的五次连续调查的高分辨率激光扫描仪数据以及流体动力学测量结果，以研究沙丘的形态动力学，它们的叠加床形以及它们在混合环境中的迁移波浪-潮汐环境（贝吉·德·索姆（Baie de Somme），英吉利海峡东部），采用了一种随机物理耦合方法。沙丘的波长约为12 m，0。

基于频谱分析的随机方法会出现一系列形态学缺陷，这些缺陷会根据各种能量条件在几个尺度范围内调节沙丘变化。这些缺陷可分为四类：（1）在排洪期间沿沙丘局部发育的约1.6 m波长的有限结构；（2）沙丘在高水动力作用之后在沙丘上堆积了约3.2 m波长的小规模叠加床形，并在能量减少时扩散了；（3）〜6.4 m的大型叠加床形，是由较小床形的形态生长所致；（4）由于沙丘在高潮波作用下的方向变化而引起的波峰线弯曲度约为25 m。

潮汐驱动下的沙丘的迁移研究表明，在高能事件中，沙丘迁移分量非常重要，平均解释方差占总迁移量的65％，而下降到32％。中等潮汐条件。记录了跨岸迁移和长期迁移成分与沿岸和跨岸沉积物的运输量的良好匹配，R ²系数高于70％。这些系数对于近海沙丘增加，其中它们对时间平均沉积物迁移的形态学响应更快，而陆上沙丘以较慢的时间尺度响应，从而导致较低的R ²系数。