This is a good reason to carry a lightweight trowel. Keep wastes at least 300 feet away from any water source. If you carry something into the backcountry, consume it or carry it out. Thousands of people coming behind you are thanking you for your courtesy and good sense. One footprint can destroy decades of growth.
Crypotobiotic crust is the foundation of life in the high desert.
It provides a seedbed for the desert plant community and serves as a sponge, retaining the precious moisture of a dry climate. The crust is also the primary source for fixation of nitrogen which is critically to all life in the desert. This crust is a complex community of microorganisms, the most important of which are called cyanobacteria. When mature, cryptobiotic soil has a lumpy, black-tinged crust. In earlier stages, the crust is almost invisible.