EGU25-11902, updated on 15 Mar 2025
https://doi.org/10.5194/egusphere-egu25-11902
EGU General Assembly 2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
Spatial and temporal evolution of tidal channels' submarine geomorphology in the northern Venice Lagoon, Italy
Taha Lahami1,2, Irene Guarneri2, Daphnie Galvez2, Antonio Petrizzo2, Mariacristina Prampolini2, Valentina Grande2, Giorgio Castellan2, Federica Rizzetto2, Federica Foglini2, and Fantina Madricardo2
Taha Lahami et al.
  • 1Department of Biology, University of Naples Federico II, Naples, Italy
  • 2National Research Council, Institute of Marine Sciences (CNR-ISMAR), Italy

Tidal environments are highly dynamic systems whose evolution is shaped by a complex interplay of natural and anthropogenic factors. These systems respond to intricate hydrodynamic processes such as tidal asymmetry, sedimentation, and channel morphodynamics. These environments are characterised by the presence of tidal channels, which are critical for ecosystem functioning as they facilitate the exchange of water, sediments, and nutrients. Despite their importance, the spatial and temporal evolution of tidal channels remains insufficiently studied, particularly in terms of their morphological and sedimentological characteristics. Information on their evolution is particularly relevant in densely populated areas, where natural processes are closely connected with anthropogenic pressures.

This study aims to explore the tidal channel seafloor characteristics and spatiotemporal evolution focussing on a case study from the northern Venice Lagoon.

With this aim, high-resolution MultiBeam Echo-Sounder (MBES) bathymetry and backscatter data were acquired over an eight-year period, in 2013 and 2021. Ground truth sediment samples and seabed video footage were collected to characterize the substrate and validate the maps produced from the MBES acoustic data. Morphological features were analyzed in a GIS environment using bathymetric data.  The analysis identified both erosional and depositional features, finding depositional features dominating the study area. A seafloor sediment map was generated by classifying backscatter data using the unsupervised Jenks Natural Breaks algorithm. To assess changes over time, data from 2013 were compared to those gathered in 2021. Our findings suggest that deposition processes were predominant, with an overall net sediment accumulation of 542.7 · 10³ m³, strongly influenced by anthropogenic activity, related to the recent operation of mobile barriers at the lagoon inlets and salt marsh restauration efforts in the area.

In the context of rising mean sea levels and associated adaptation measures, this work not only enhances understanding of highly valuable and vulnerable transitional environments but also helps to assess the long-term impact of anthropogenic interventions.

Aknowledgements

This work was partially carried out within the Research Program Venezia 2021, with the contribution of the Provveditorato for the Public Works of Veneto, Trentino Alto Adige and Friuli Venezia Giulia, provided through the concessionary of State Consorzio Venezia Nuova and coordinated by CORILA. The authors acknowledge the facilities of the International Centre for Advanced Studies on River-Sea Systems DANUBIUS-RI (https://www.danubius-ri.eu/ ) in undertaking this research.

How to cite: Lahami, T., Guarneri, I., Galvez, D., Petrizzo, A., Prampolini, M., Grande, V., Castellan, G., Rizzetto, F., Foglini, F., and Madricardo, F.: Spatial and temporal evolution of tidal channels' submarine geomorphology in the northern Venice Lagoon, Italy, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-11902, https://doi.org/10.5194/egusphere-egu25-11902, 2025.