Title |
A test of critical thresholds and their indicators in a desertification‐prone ecosystem: more resilience than we thought
|
---|---|
Published in |
Ecology Letters, December 2012
|
DOI | 10.1111/ele.12045 |
Pubmed ID | |
Authors |
Brandon T. Bestelmeyer, Michael C. Duniway, Darren K. James, Laura M. Burkett, Kris M. Havstad |
Abstract |
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. Recovery occurred at the same rate irrespective of grazing history, suggesting that critical thresholds were not crossed, even at low cover levels. Grass cover, but not patch size metrics, predicted variation in recovery rates. Some transition-prone ecosystems are surprisingly resilient; management of grazing impacts and simple cover measurements can be used to avert undesired transitions and initiate restoration. |
X Demographics
Geographical breakdown
Country | Count | As % |
---|---|---|
United States | 5 | 38% |
Argentina | 1 | 8% |
Mexico | 1 | 8% |
Sweden | 1 | 8% |
Unknown | 5 | 38% |
Demographic breakdown
Type | Count | As % |
---|---|---|
Scientists | 6 | 46% |
Members of the public | 5 | 38% |
Science communicators (journalists, bloggers, editors) | 2 | 15% |
Mendeley readers
Geographical breakdown
Country | Count | As % |
---|---|---|
United States | 9 | 3% |
Brazil | 2 | <1% |
Sweden | 1 | <1% |
South Africa | 1 | <1% |
United Kingdom | 1 | <1% |
France | 1 | <1% |
Mexico | 1 | <1% |
Tunisia | 1 | <1% |
Venezuela, Bolivarian Republic of | 1 | <1% |
Other | 1 | <1% |
Unknown | 246 | 93% |
Demographic breakdown
Readers by professional status | Count | As % |
---|---|---|
Researcher | 75 | 28% |
Student > Ph. D. Student | 47 | 18% |
Student > Master | 24 | 9% |
Student > Bachelor | 18 | 7% |
Professor > Associate Professor | 18 | 7% |
Other | 47 | 18% |
Unknown | 36 | 14% |
Readers by discipline | Count | As % |
---|---|---|
Agricultural and Biological Sciences | 99 | 37% |
Environmental Science | 79 | 30% |
Earth and Planetary Sciences | 17 | 6% |
Engineering | 6 | 2% |
Medicine and Dentistry | 2 | <1% |
Other | 9 | 3% |
Unknown | 53 | 20% |