Channels'shape evolution detected by UAVs in a restored salt marsh

Tidal processes that regulate sediment accretion rates strongly influence the evolution of salt marshes. The assessment of the erosion and deposition balance is therefore crucial to find out the best restoration strategies. This work presents the first results of an integrated approach for monitoring channels’ morphodynamics over a six-year time frame in a low energy restored salt marsh at Poplar Island (Maryland, USA). The combined use of an Unmanned Aerial Vehicle (UAV) and traditional GPS cross sections surveys was adopted to detect the current shape of the channels. Due to the site extent of 400 m by 400 m, three missions were performed flying at a 40 m altitude. The comparison with the initial as-built survey showed the effects of erosion and deposition phenomena. The technique provided reliable results at low cost, allowing an accurate assessment of the morphodynamics over time, thanks to both high spatial resolution and the precise imageries georeferencing.