Fig 1.
The composition of storm wrack in experimental plots and eastern Florida coastline.
Proportions of different components of storm wrack A) collected from experimental removal plots (see S5 Fig for proportions in each block) and B) from surveys of wrack observed at 21 coastal dune sites along the north-east Florida coastline following hurricane Irma. C) Mean (± standard error; n = 15) C:N ratio of organic materials from experimental wrack removal plots.
Fig 2.
Changes in the abundance of grass species in control plots during the first 16 months of the experiment.
Mean (± se) cover of P. amarum, S. virginicus and U. paniculata in control plots (March 2018 –July 2019).
Fig 3.
Effects of wrack removal on plant variables.
All plots show the partial residuals from linear models accounting for experimental block as a function of treatment type. The variables shown are: log-transformed cover of all plants (A), all grasses (B), P. amarum (C), S. virginicus (D), and U. paniculata (E)I. Plant variables were taken after 16 months. Grey area are the 95% confidence intervals.
Fig 4.
Effects of wrack on geomorphological variables.
Laser scan images of control (A) and removal (B) plots from initial and final geomorphological data collection time points and respective heat maps showing changes in elevation between the two time points. Blue edge to heat map represents seaward side of dune. C- E: All plots show the partial residuals from linear models accounting for experimental block as a function of treatment type. The variables shown are: mean elevation above sea level at initial data collection point (C) and final data collection point (D), and difference of elevation between first and final time point (elevational change).I (E). Grey areas are the 95% confidence intervals.