TY - JOUR
T1 - Sandy beaches in low-energy, non-tidal environments
T2 - Linking morphological development to hydrodynamic forcing
AU - Ton, Anne M.
AU - Vuik, Vincent
AU - Aarninkhof, Stefan G.J.
PY - 2021
Y1 - 2021
N2 - The morphodynamic behaviour of low-energy beaches is poorly understood, compared to that of exposed coasts. This study analyses the morphological development of sandy, low-energy beaches and the steering hydrodynamic processes. Four densely-monitored study sites in the non-tidal lake Markermeer in the Netherlands offered a unique opportunity to examine the relation between their hydraulic boundary conditions and morphodynamics. Regular bathymetric surveys were executed at all locations. Furthermore, the wave climate was monitored at one of these four sites. All four sites exhibit a commonly found low-energy beach morphology, with a narrow beach face and a low-gradient, subaqueous platform. This platform reaches an equilibrium depth quickly and then stays relatively stable. The stable elevation of the platform is located near Hallermeier's depth of closure. A sediment budget analysis over time demonstrates that the beach faces at all study sites have eroded during more energetic periods, and sediment accumulated offshore. During the monitoring periods of 2 to 4 years, the elevation of the platforms reached an equilibrium, but other morphological dimensions are still developing. The new insights gained from this study enable the prediction of platform elevations along sandy beaches in low-energy, non-tidal environments, and have contributed to our insight in the underlying processes driving the morphological evolution.
AB - The morphodynamic behaviour of low-energy beaches is poorly understood, compared to that of exposed coasts. This study analyses the morphological development of sandy, low-energy beaches and the steering hydrodynamic processes. Four densely-monitored study sites in the non-tidal lake Markermeer in the Netherlands offered a unique opportunity to examine the relation between their hydraulic boundary conditions and morphodynamics. Regular bathymetric surveys were executed at all locations. Furthermore, the wave climate was monitored at one of these four sites. All four sites exhibit a commonly found low-energy beach morphology, with a narrow beach face and a low-gradient, subaqueous platform. This platform reaches an equilibrium depth quickly and then stays relatively stable. The stable elevation of the platform is located near Hallermeier's depth of closure. A sediment budget analysis over time demonstrates that the beach faces at all study sites have eroded during more energetic periods, and sediment accumulated offshore. During the monitoring periods of 2 to 4 years, the elevation of the platforms reached an equilibrium, but other morphological dimensions are still developing. The new insights gained from this study enable the prediction of platform elevations along sandy beaches in low-energy, non-tidal environments, and have contributed to our insight in the underlying processes driving the morphological evolution.
KW - Depth of closure
KW - Low-energy
KW - Morphodynamics
KW - Sandy lake beach
UR - http://www.scopus.com/inward/record.url?scp=85097057004&partnerID=8YFLogxK
U2 - 10.1016/j.geomorph.2020.107522
DO - 10.1016/j.geomorph.2020.107522
M3 - Article
AN - SCOPUS:85097057004
VL - 374
SP - 1
EP - 11
JO - Geomorphology
JF - Geomorphology
SN - 0169-555X
M1 - 107522
ER -