Survival patterns and population stability of cliff plants suggest high resistance to environmental variability

Cliffs are marginal and poorly studied habitats that are home to a high proportion of endemic or threatened species. Here, we review the survival patterns and population dynamics of plants growing on vertical cliffs and compare them to other plants with similar life histories that grow on the ground. To this end, we have compiled studies of cliff and ground plants from two main sources: MONITO and COMPADRE. The resulting data set includes a total of 242 populations of 139 plant species of similar life forms monitored for several years in the northern hemisphere. We tested whether survival rates (Sx), population growth rates, and their temporal variability (lambda: λ±SD) showed similar patterns between cliff and ground plants, and the relationship between them. The review indicates that cliff plants have higher survival rates for both seedlings and older life stages and more stable and less variable population trends over time. Only the survival of post-seedling stages is highly correlated with population dynamics. Altogether, these results suggest that cliff plants may be better equipped to withstand environmental variability than non-specialized plants in more competitive environments.