Drylands are prone to desertification as human disturbances degrade desert ecosystems and limit their capacity to bio-produce. Biological soil crusts, a specialized community of lichen and cyanobacteria, are particularly vulnerable to these disturbances. To gauge the effects of anthropogenic disturbance on soil particle size and soil crust growth, Collema, a widely-distributed genus of soil lichen, was used as an indicator of overall ecosystem health. We used the visual percent cover method in

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... our "low disturbance" and four "high disturbance" sites to assess Collema health under various anthropogenic stressors. We also compared Collema presence and soil properties as distance increased away from disturbance. We found that sites with high disturbance had no Collema presence, while sites of low disturbance had Collema presence. We found that in low disturbance sites Collema abundance and density increased as we moved away from disturbance. The ecological importance of biological soil crusts is often underestimated and therefore left out of conservation and restoration efforts. Assessing optimal growing environments for Collema may shift conservation efforts to focus on preserving these valuable biological soil crusts.