Figure 19. Rhizomes help hold sand in place and spread the colonization of dune grasses. 

 Eastern Alabama near Florida/Alabama state line (March 1991) 



Because dunes are effective in sediment stabilization and trapping, dune 

 vegetative cover and form are interrelated and can be classified as such (Short 

 and Hesp 1982). Densely vegetated dunes are associated with fixed, shore- 

 parallel dune ridges. As vegetation decreases, dune patterns range from 

 discontinuous ridges to hummock dunes to small blowouts. Minimally 

 vegetated dunes show residual knolls, barchanoid forms with crescent shapes 

 and downwind horns, and transverse blowouts or hollows. 



Dune vegetation can be damaged or destroyed by various diseases and 

 natural and human-induced disturbances. Climatic and meteorologic stresses, 

 particularly droughts and storms, fire, grazing by wildlife and domesticated 



Chapter 3 Variable Coastal Features 



49 



