One of the most interesting organisms in the cryptobiotic mix is cyanobacteria.

Cyanobacteria is a photosynthetic bacteria also known as blue-green algae.  Cyanobacteria has mucousy tendrils that hold silica and sand particles together

Some species of cyanobacteria, like Microcoleus vaginatus, do not have protection from UV rays so they hide from the sun until it rains. When Microcoleus is moistened it travels from its hiding place .2-.5 mm below the surface up to the surface. When the soil dries out it returns to its hiding place. Other cyanobacteria (Scytonema and Nostoc) that have UV screening pigments are found directly on the soil surface.

Cryptobiotic soil might “crunch” when you step on it. This is usually the dried out, darker version of the soil. All the organisms that make up cryptobiotic soil are fairly unique as they can dry out completely between waterings and not die. This is similar to the way other organisms like bears, hummingbirds, lizards, and snakes go into hibernation or dormancy.

Because cryptobiotic soil crusts hold sand and other soil components together they decrease wind and water erosion, allowing plants to grow and water to be retained. Alternatives to biological soil crusts are abiotic (physical and chemical) crusts that inhibit the infiltration of water into the soil.

USGS and Grand Staircase-Escalante National Monument scientists have been researching cryptobiotic soil crusts for years. An excellent technical paper, Biological Soil Crusts: Ecology and Management, can be downloaded from the BLM.