Spatial early warning signals in a lake manipulation. Issue 10 (2nd October 2017)

• Record Type: Journal Article
• Authors: Butitta, Vince L.; Carpenter, Stephen R.; Loken, Luke C.; Pace, Michael L.; Stanley, Emily H.
• Is Part Of: Ecosphere. Volume 8:Issue 10(2017)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2017-10-02
• Subjects: algal bloom -- critical transition -- early warning indicators -- ecosystem experiment -- regime shift -- resilience -- spatial analysis; Ecology -- Periodicals; Ecology; Periodicals; 577.05
• DOI: 10.1002/ecs2.1941
• Languages: English
• ISSNs: 2150-8925

Abstract

Abstract: Rapid changes in state have been documented for many of Earth's ecosystems. Despite a growing toolbox of methods for detecting declining resilience or early warning indicators (EWIs) of ecosystem transitions, these methods have rarely been evaluated in whole‐ecosystem trials using reference ecosystems. In this study, we experimentally tested EWIs of cyanobacteria blooms based on changes in the spatial structure of a lake. We induced a cyanobacteria bloom by adding nutrients to an experimental lake and mapped fine‐resolution spatial patterning of cyanobacteria using a mobile sensor platform. Prior to the bloom, we detected theoretically predicted spatial EWIs based on variance and spatial autocorrelation, as well as a new index based on the extreme values. Changes in EWIs were not discernible in an unenriched reference lake. Despite the fluid environment of a lake where spatial heterogeneity driven by biological processes may be overwhelmed by physical mixing, spatial EWIs detected an approaching bloom suggesting the utility of spatial metrics for signaling ecological thresholds.