A test of critical thresholds and their indicators in a desertification-prone ecosystem (Sciences Indexed Since 1998)

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A test of critical thresholds and their indicators in a desertification-prone ecosystem: more resilience than we thought

submitted by tozzaka

Theoretical models predict that drylands can cross critical thresholds, but experimental manipulations to evaluate them are non-existent. We used a long-term (13-year) pulse-perturbation experiment featuring heavy grazing and shrub removal to determine if critical thresholds and their determinants can be demonstrated in Chihuahuan Desert grasslands. We asked if cover values or patch-size metrics could predict vegetation recovery, supporting their use as early-warning indicators. We found that season of grazing, but not the presence of competing shrubs, mediated the severity of grazing impacts on dominant grasses.

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