Author(s): Francesco Caponi; Daniel A. S. Conde; David F. Vetsch

Linked Author(s): David Vetsch

Keywords: Lagrangian model; Plant seed dispersal; Hydrochory; Alpine floodplain; Field experiment

Abstract: Fluvial seed dispersal is a key factor controlling riparian vegetation dynamics along river margins. Seeds and vegetative propagules are transported by water flow along river channels, allowing plants to colonize new sites and favoring plant biodiversity. However, the specific relationship between river discharge, river morphology and seed dispersal remain largely unexplored. To fill this gap, we combine a new numerical model deploying a Eulerian-Lagrangian approach to track plant seed trajectories and deposition and a series of outdoor field experiments using seed mimics. Here we present the workflow and preliminary observations from the experiments conducted in an alpine floodplain in Switzerland. By linking deposition location and transport time of seed mimic with the spatial and temporal distribution of hydro-morphological units, we can provide a quantification of the role played by river hydro-morphology on seed dispersal. This quantification may support river managers in mitigating impacts of flow diversions and design better e-flows regulations favoring plant biodiversity and ecosystem resilience.

DOI: https://doi.org/10.3850/978-90-833476-1-5_iahr40wc-p0413-cd

Year: 2023