Hysteresis in an experimental phytoplankton population

TY - JOUR

T1 - Hysteresis in an experimental phytoplankton population

AU - Faassen, Elisabeth J.

AU - Veraart, Annelies

AU - Van Nes, E.H.

AU - Dakos, V.

AU - Lürling, M.

AU - Scheffer, M.

N1 - 5809; AqE; ME; Data Archiving: Data archived at Datadryad

PY - 2015

Y1 - 2015

N2 - The road to recovery of a deteriorated system is often different, and fraught with more barriers, than the path to the system's deterioration. This phenomenon is called hysteresis, and is inherent to systems presenting alternative stable states. In such systems, the stability of a given state is the product of positive feedback loops. A broad range of natural systems have been predicted to show hysteretic behaviour, but hysteresis has so far only been unambiguously demonstrated at cellular or metabolic levels, not yet at the population or ecosystem level. To extend our understanding of hysteresis at the population level, we performed an experiment on light-stressed cyanobacteria and found hysteresis between alternative stable states. Furthermore, during the experiment, the cyanobacteria adapted physiologically to high light levels, and deviated from their theoretically predicted pathway of hysteresis, therewith also avoiding extinction. Our experiment confirmed that a population that loses resilience due to deteriorating external conditions can show a delayed – hysteretic – recovery-response when conditions are improved. This population-level study also indicates that the slowness of these systems may obscure the true state they are in, which is important to factor into ecosystem monitoring. Additionally, we show that adaptation can drastically alter the systems’ predicted behaviour to ecosystem management. Flexibility of species and slowness should, therefore, be included in the monitoring and prediction of ecosystem responses to environmental changes.

AB - The road to recovery of a deteriorated system is often different, and fraught with more barriers, than the path to the system's deterioration. This phenomenon is called hysteresis, and is inherent to systems presenting alternative stable states. In such systems, the stability of a given state is the product of positive feedback loops. A broad range of natural systems have been predicted to show hysteretic behaviour, but hysteresis has so far only been unambiguously demonstrated at cellular or metabolic levels, not yet at the population or ecosystem level. To extend our understanding of hysteresis at the population level, we performed an experiment on light-stressed cyanobacteria and found hysteresis between alternative stable states. Furthermore, during the experiment, the cyanobacteria adapted physiologically to high light levels, and deviated from their theoretically predicted pathway of hysteresis, therewith also avoiding extinction. Our experiment confirmed that a population that loses resilience due to deteriorating external conditions can show a delayed – hysteretic – recovery-response when conditions are improved. This population-level study also indicates that the slowness of these systems may obscure the true state they are in, which is important to factor into ecosystem monitoring. Additionally, we show that adaptation can drastically alter the systems’ predicted behaviour to ecosystem management. Flexibility of species and slowness should, therefore, be included in the monitoring and prediction of ecosystem responses to environmental changes.

KW - national

UR - http://dx.doi.org/10.5061/dryad.8gr58

U2 - 10.1111/oik.02006

DO - 10.1111/oik.02006

M3 - Article

SN - 0030-1299

VL - 124

SP - 1617

EP - 1623

JO - Oikos

JF - Oikos

IS - 12

ER -