Title: Pilot Drone Mapping of Marsh Biomass and Species for estimating Vegetation Drag

Lead Investigator / onsite-contact: Heidi Nepf

Affiliation: Civil and Environmental Engineering, Massachusetts Institute of Technology

The flow resistance provided by coastal marshes mitigates flooding by slowing storm surge and damping waves. It also controls the flooding and draining of the marsh platform during the tidal cycle. The flow resistance (drag) provided by a marsh varies with seasonal growth, marsh erosion, and marsh area gained by restoration. It would be useful to have a method that directly measures marsh drag, which would improve the prediction of flooding and inform coastal planning, risk assessment, and restoration design. The Nepf lab has developed models that estimate drag on individual plants as a function of plant shape and rigidity, velocity and flow depth. In this project, we will develop a method to measure the number of plants per bed area and the species using drones to map biomass, plant height, and identifying geometric features. Combining measured plant density (plant per bed area) with predicted drag per plant will yield a measurement of flow resistance per marsh area. MASS DOT will fly the pilot drone mission to measure the spatial distribution of biomass, species, and plant height.