The role of cyanobacteria in stabilization of sand dunes in Southern Israel

Sand dunes are an unstable habitat where plants suffer from cover and exposure of sand moving by wind. The establishment of higher plants leads to local decrease in wind velocity, deposition of airborne fine grained particles, and the establishment of filamentous cyanobacteria. Aggregation of clay and silt sized particles by cyanobacterial filaments and gelatinous polysaccharids excreted by their trichomes leads to trapping of these particles. Further development of cyanobacteria leads to trapping of additional fine grained particles, improves the soil's moisture regime, and presumably increases soil stability and fertility through development of nitrogen fixing cyanobacteria (i.e. Nostoc). These changes lead to development of different higher plant communities in the processes of plant succession. The microphytic crust of the climax vegetation presumably includes mosses and cyanobacteria and protects the stabilized sands, from wind erosion.