Predominant landward skewing of tidal meanders

Abstract

Highly sinuous, high-amplitude meander bends shaped by unidirectional, downstream-oriented flows in alluvial rivers are predominantly upstream-skewed, offering an opportunity to infer flow direction from meander planforms. In contrast,

Morphometry of Tidal Meander Cutoffs Indicates Similarity to Fluvial Morphodynamics

“…Considered alongside previous studies, our results indicate a complete morphodynamic analogy between tidal and fluvial meandering channels from meander inception to cutoff (Finotello et al., 2018, 2022; Gao, Finotello, & Wang, 2022; Leuven et al., 2018). The unification of tidal and fluvial meander morphodynamics allows for extending classical techniques for modeling meandering rivers (Bogoni et al., 2017; Howard & Knutson, 1984; Parker et al., 2011; Seminara et al., 2001) to tidal wetland contexts, where meandering is ubiquitous and yet routinely omitted.…”

“…The perceived stability of sinuous tidal channels-or at least the relative subtlety of their meandering dynamics-has often been attributed to the unique ecomorphodynamics of coastal environments, where flow bidirectionality is paramount (Fagherazzi et al, 2004;Hughes, 2012;Solari et al, 2002). However, recent studies highlighted morphodynamic commonalities between fluvial and tidal meanders, with similar planform dynamics, width-adjusted migration rates, and morphodynamic regimes in high-amplitude bends (Finotello et al, 2018(Finotello et al, , 2022Gao, Finotello, & Wang, 2022;Leuven et al, 2016Leuven et al, , 2018. This motivated us to question the perceived paucity of tidal meander cutoffs, and to further demonstrate the parallels between tidal and fluvial meandering channels.…”

Hydrodynamics of Meander Chute Cutoffs in Microtidal Mudflats

“…In fact, tidal cutoffs are much more widespread than previous thought and can be detected in various coastal wetlands with high-resolution imagery data (Figure 1, also see C. , despite that the visible evidence of meander cutoff there is extremely diminished by increased channel density and hydrological connectivity (Marani et al, 2003;Rinaldo et al, 1999aRinaldo et al, , 1999bXie et al, 2020;Z. Yang, Qiao, et al, 2022), reduced channel size (Finotello et al, 2020;C. Gao, Finotello, & Wang, 2022), as well as possible dense vegetation cover (Kearney & Fagherazzi, 2016;Schwarz et al, 2022).…”

“…To simplify the interpretation of velocity‐data time series and filter out outliers, AD2CP data were then phase averaged and subdivided into two distinct groups based on the values of the high‐tide water depth ( Y H ) observed during each tidal cycle (C. Gao, Finotello, D'Alpaos, et al., 2022; Voulgaris & Meyers, 2004; Y. P. Wang et al., 2013). According to the time series change characteristics of water depth in this research (Figures 6a–6c), the first, third, fifth, seventh, and ninth tidal cycles were classified as “high‐amplitude tides” ( HATs ), whereas all the other tidal cycles were considered as “low‐amplitude tides” ( LATs ).…”

“…Johnson, 1929). However, similar morphodynamics shared by fluvial and tidal meanders, in terms of planform geometries (Finotello et al, 2020;Marani et al, 2002), width-adjusted migration rates (Finotello et al, 2018), and hydrodynamic regimes in high-amplitude bends (Fagherazzi et al, 2004;C. Gao, Finotello, & Wang, 2022), may suggest otherwise.…”