# Can Vegetation Removal Successfully Restore Coastal Dune Biodiversity?
## 2 Materials and Methods
### Removal Experiments  
Three separate treatments were tested (Figure 1). For each set of treated dunes, there were paired untreated control dunes and mobile dunes were considered as the restoration reference for all treatments (Figure 1e) (other dunes were monitored under the LTER but were not included in this study). A summary table of the overall experimental design has been included in the supplementary information (Table S1).  
1. Fixed Dune Treatment: In October 2005, perennial vegetation was removed from the entire fixed dune in a grid formation using a bulldozer, to accurately reach the desired amount of remaining vegetation (Figure 1b). The removal reduced the vegetation from 31-50% to approximately 15-20% for each dune [69]. Three dunes were treated and three control dunes were monitored in parallel.
2. Semi-Fixed Treatment: In November 2012, an experiment was conducted on four semi-fixed dunes, which had a range of 16-30% average PPC prior to treatment. This time, the experiment involved removal of all vegetation from the wind-facing slope of four semi-fixed treated dunes. The vegetation remaining on the crest and slip-face was left intact (Figure 1d). This experimental  
Figure 1: Dune treatments investigated in Nizzanim Long Term Ecological Research (LTER); (**a**) Fixed untreated (control) dune; (**b**) Fixed treated (**c**) Semi-fixed untreated (control); (**d**) Semi-fixed treated; (**e**) Mobile dune (reference) dune; (**f**) Off-road vehicle disturbance. Semi-fixed and Fixed Treated dunes were paired with un-treated Semi-fixed and Fixed untreated control dunes respectively. All treated dunes were compared to their un-treated control pair and Mobile dunes as the restoration reference. Disturbed dunes were exposed to illegal, un-quantified off-road vehicle disturbance. They were compared to both Mobile and Semi-fixed untreated dunes to examine their relative composition. Frames of the different dune types shown are colour consistent throughout all figures.  
design was chosen in order to leave some vegetation needed for animal survival, while more closely emulating the distribution of natural vegetation found on mobile dunes (see 77). Four untreated semi-fixed dunes were selected as controls (Figure 1c).
3. Disturbed Dunes Treatment: Off-road vehicle (ORV) disturbance has been occurring illegally in the reserve for many years (Figure 1f), which began prior to the initiation of the experimental plots. We began monitoring these dunes in 2012, in order to study the impact of ORVs on dune biodiversity. We consider these dunes as 'treated' with an unquantified press disturbance. The exact natural state of these dunes prior to the disturbance is unknown; on the one hand, one might assume they were similar to mobile dunes based on historical aerial photos from 1965 and 1999 (69). On the other hand, most dunes in the immediate vicinity are semi-fixed. Disturbed dunes were therefore compared with both mobile and un-treated semi-fixed dunes as the reference dunes. Annual plants are almost entirely absent from disturbed dunes and as such this taxon was not monitored on these dunes.