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Abstract Research aimed at identifying indicators of persistent abrupt shifts in ecological communities, a.k.a regime shifts, has led to the development of a suite of early warning signals (EWSs). As these often perform inaccurately when applied to real-world observational data, it remains unclear whether critical transitions are the dominant mechanism of regime shifts and, if so, which EWS methods can predict them. Here, using multi-trophic planktonic data on multiple lakes from around the world, we classify both lake dynamics and the reliability of classic and second generation EWSs methods to predict whole-ecosystem change. We find few instances of critical transitions, with different trophic levels often expressing different forms of abrupt change. The ability to predict this change is highly processing dependant, with most indicators not performing better than chance, multivariate EWSs being weakly superior to univariate, and a recent machine learning model performing poorly. Our results suggest that predictive ecology should start to move away from the concept of critical transitions, developing methods suitable for predicting resilience loss not limited to the strict bounds of bifurcation theory.
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This content will become publicly available on February 1, 2027
Ecosystem Experiments: How Does Manipulation Rate Affect Indicators of Resilience?
<sc>Abstract</sc> Experiments on entire ecosystems have contributed knowledge on effects of atmospheric CO2and climate change, environmental pollutants, trophic cascades, response of fisheries to management, consumer interactions, ecosystem resilience and stability, and early warning indicators of critical transitions in ecosystem state. Rate of change in external drivers of an ecosystem such as climate warming, inflow of water or nutrients, or harvest of apex predators may affect signals of critical transitions but rates of change of drivers are rarely considered in whole-ecosystem studies. We studied effects of drivers’ rates of change on indicators of critical transitions using models for whole lake manipulations of nutrient enrichment, light-absorbing substances, and apex predators. Results show that times of signals from indicators relative to times of critical transitions can vary depending on the rate of external drivers, including the rate of manipulation in whole-ecosystem experiments.
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- PAR ID:
- 10667212
- Publisher / Repository:
- Ecosystems
- Date Published:
- Journal Name:
- Ecosystems
- Volume:
- 29
- Issue:
- 1
- ISSN:
- 1432-9840
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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