Surficial sediment erodibility from time-series measurements of suspended sediment concentrations: development and validation
Surficial sediment erodibility from time-series measurements of suspended sediment concentrations: development and validation
复制标题
悬浮沉积物浓度时间序列测量的表层沉积物侵蚀性：开发和验证
DOI：
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发表时间：
2017
期刊：
影响因子：
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通讯作者：
J. Winterwerp
中科院分区：
文献类型：
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作者：
R. Mathew;J. Winterwerp
细颗粒泥沙输运的数值模型依赖于不同的方法来参数化表层泥沙地层的侵蚀特性。这些属性，即侵蚀的临界剪切应力和侵蚀速率系数，是至关重要的再现系统的短期和长期的沉积动力学。参数化这些属性的方法涉及对沉积物样品的专门实验室测量或通过模型校准进行优化。基于对小而窄的河口悬沙浓度（SSC）随潮汐周期变化规律的观测，提出了一种用于定量分析表层侵蚀特性的方法，即卷吸通量法。这种方法的结果被证明是类似的侵蚀数据，用于制定标准的线性侵蚀制定由不同的作者。从夹带通量法推断的侵蚀特性也比较直接测量的可蚀性沉积物样品从同一地点使用阵风微观系统装置。这两种方法的有利比较表明，卷吸通量方法可以用来推断和量化类似的小而窄的河口表层沉积物地层的可蚀性。这一方法有某些优点，主要是易于实施，而且它使用的SSC时间序列通常预期可用于特定地点的研究或模型应用。还提出了选择适当的数据集的方法的应用指南。
Numerical models of fine sediment transport depend on different approaches to parameterize the erosion properties of surficial sediment strata. These properties, namely the critical shear stress for erosion and the erosion rate coefficient, are crucial for reproducing the short-term and long-term sediment dynamics of the system. Methods to parameterize these properties involve either specialized laboratory measurements on sediment samples or optimization by model calibration. Based on observations of regular patterns in the variation of suspended sediment concentrations (SSC) over the tidal cycle in a small, narrow estuary, an alternate approach, referred to as the entrainment flux method, for quantifying the erosion properties of surficial bed strata is formulated and applied. The results of this method are shown to be analogous to the erosion data used to formulate the standard linear erosion formulation developed by various authors. The erosion properties inferred from the entrainment flux method are also compared to direct measurements of erodibility on sediment samples from the same site using the Gust microcosm apparatus. The favorable comparison of the two approaches suggests that the entrainment flux method can be used to infer and quantify the erodibility of surficial sediment strata in similar small and narrow estuaries. This method has certain advantages, chiefly its ease of implementation and the fact that it uses SSC time series which would typically be expected to be available for the study of or for model application at a given site. Guidelines for selecting the appropriate dataset for the application of the method are also presented.