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Related Experiment Video

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Following the Dynamics of Structural Variants in Experimentally Evolved Populations

Following the Dynamics of Structural Variants in Experimentally Evolved Populations

Published on: February 3, 2023

Allowing variance may enlarge the safe operating space for exploited ecosystems.

Stephen R Carpenter¹, William A Brock², Carl Folke³

¹Center for Limnology, University of Wisconsin-Madison, Madison, WI 53706; srcarpen@wisc.edu.

Proceedings of the National Academy of Sciences of the United States of America

|October 7, 2015

Summary

Reducing short-term variability in ecosystem services can paradoxically increase risks and lead to undesirable ecosystem states. Sustainable management requires embracing variation to maintain resilience and adapt to change.

Keywords:

adaptive management critical transition ecosystem resilience variance

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Area of Science:

Ecosystem Management
Ecological Resilience
Environmental Planning

Background:

Variable ecosystem services complicate effective planning and resource management.
Strategies aiming to reduce short-term variability may be preferred for predictability.
Continuous short-term variance reduction can lead to adverse long-term ecosystem changes.

Purpose of the Study:

To investigate the effects of managing short-term variance on ecosystem services.
To assess the risk of crossing critical ecosystem thresholds due to variance management.
To understand the interplay between variance management and ecosystem resilience.

Main Methods:

Analysis of three well-understood ecosystem service models: lake eutrophication, wild population harvest, and rangeland herbivore yield.
Simulations and theoretical investigations into the consequences of reducing short-term variance.
Examination of how variance management impacts safe operating spaces and adaptive capacity.

Main Results:

Actions to decrease short-term variance increased the risk of crossing critical ecosystem thresholds.
Reduced variance led to less desirable ecosystem states and increased ecosystem fragility.
Variance management suppressed crucial information for adaptive strategies and cancelled resilience signals.

Conclusions:

Managing for decreased short-term variance can create ecosystem fragility and increase the risk of undesirable states.
Variance management is inseparably linked with the management of ecosystem resilience.
Allowing for variation, learning, and flexibility is key for adaptive management and sustaining capacity to deal with change.