Laboratory study on biophysicochemical improvement of desert sand

Losses of soil biodiversity, stability, and fertility are primary factors causing degradation in drylands; therefore, finding a sustainable conservation practice is a critical issue for reversing desertification in these areas. By inoculation of two filamentous cyanobacteria, i.e., Nostoc punctiforme and Microcoleus vaginatus, on infertile desert sand, this study examined the component, structure, permeability, and strength of the created biocrusts. Moreover, wind erodibility of the biocrusts was tested by a wind tunnel, equipped with a sand particle counter (SPC). With having higher amounts of polysaccharide and Chl-a contents after 21 days of cultivation, the M. vaginatus-formed biocrust showed comparatively higher values of nutrients and strength and lower values of permeability and erodibility. Concerning wind erosion of the sand samples, both biocrusts reduced surface erosion of the sand several thousand times, in conditions without saltating particles. Nevertheless, in the presence of saltating particles, the erosion resistance of the treated samples decreased significantly.