# Can Vegetation Removal Successfully Restore Coastal Dune Biodiversity?
## 4 Discussion
### Implications for Conservation Management  
Disturbance is a fundamental part of natural coastal dune processes, and encroachment by grasses, shrubs and woody plants has most likely occurred due to the removal of this process [4; 33].  
Geomorphologists increasingly recommend that remobilization of inner dunes should consider the dune-beach system as a whole, arguing for an integrated dynamic approach that recreates the natural disturbances such as wind erosion and sand burial [15; 24; 40; 126]. Our results provide support to the growing body of evidence that restoration attempts should promote, not diminish, the degree of disturbance in coastal dune systems. e.g., [31; 38; 49].  
When comparing the pulse treatments, vegetation removal of the wind-facing slopes of semi-fixed dunes appeared to be more effective than grid formation removal of fixed dunes, but since the experiments are not equivalent this can only be inferred. An initial pulse disturbance is likely needed to remove perennial vegetation, but continued press disturbance appeared to more closely match conditions found on mobile dunes, at least for faunal taxa. While the unregulated use of ORVs as a method for maintaining dune mobility is certainly not recommended, previous evidence has demonstrated the benefit of press disturbances to plant and arthropod species [15; 31; 49], ORV disturbance has severe impacts on annual plant species, so other forms of press disturbance such as grazing could be more beneficial.  
Grazing has been successful in increasing both plant and arthropod diversity on coastal dunes [49; 127]. However, domestic grazers may affect the composition (of vegetation) differently than wild grazers [128]. A review of the effects of grazing by domestic livestock showed both positive or negative impact on diversity, often increasing diversity at the landscape level but reducing alpha diversity at the very local scale [19].  
Depending on the reference species, grazing can have a positive or negative impact on richness and composition [34; 127; 129; 130]. Ground beetles and reptiles are often negatively affected by management practices such as grazing and trampling [129; 131; 132]. That said, populations of _A. scutellatus_ or _S. striatus_ on disturbed dunes were not as low as in semi-fixed control dunes, suggesting that even recreational driving is less damaging than passive management (allowing shrub encroachment) for these species. Altum [133] showed that desert reptile specialists in the Egyptian desert did not respond favorably to heavy grazing in inland sand dunes, despite predictions that they may fare better than generalist species. Another study found arthropod assemblages were more diverse in response to disturbance by trampling, blowouts and burning in Danish dune grasslands [44]. Grazing management applied in coastal dune grasslands of France and Belgium was also able to control highly competitive plant species, and may be beneficial in maintaining mobile assemblages [134]. Grazing could be introduced either through re-wilding of the ecosystem or in the form of managed domestic grazers [49; 135].  
Mountain gazelles (_Gazella gazelle gazella_), the only mammalian grazers in NDNR, are unlikely to provide an adequate grazing impact in the near future [136]. Attempts to introduce camel grazing to Nizzanim on semi-fixed dunes had little effect on the perennial vegetation [137]. Other forms of grazing or press disturbances should be investigated. Reintroduction of small livestock herds (sheep and goats) are currently being trialed with Bedouin shepherds, and should be monitored carefully before further recommendations can be made with regarding to grazing.