Spatial insurance against a heatwave differs between trophic levels in experimental aquatic communities

Vad, C. F. et al. (2023) Spatial insurance against a heatwave differs between trophic levels in experimental aquatic communities. Global Change Biology, 29(11), pp. 3054-3071. (doi: 10.1111/gcb.16692) (PMID:36946870)

Abstract

Climate change-related heatwaves are major threats to biodiversity and ecosystem functioning. However, our current understanding of the mechanisms governing community resistance to and recovery from extreme temperature events is still rudimentary. The spatial insurance hypothesis postulates that diverse regional species pools can buffer ecosystem functioning against local disturbances through the immigration of better-adapted taxa. Yet, experimental evidence for such predictions from multi-trophic communities and pulse-type disturbances, like heatwaves, is largely missing. We performed an experimental mesocosm study to test whether species dispersal from natural lakes prior to a simulated heatwave could increase the resistance and recovery of plankton communities. As the buffering effect of dispersal may differ among trophic groups, we independently manipulated the dispersal of organisms from lower (phytoplankton) and higher (zooplankton) trophic levels. The experimental heatwave suppressed total community biomass by having a strong negative effect on zooplankton biomass, probably due to a heat-induced increase in metabolic costs, resulting in weaker top-down control on phytoplankton. While zooplankton dispersal did not alleviate the negative heatwave effects on zooplankton biomass, phytoplankton dispersal enhanced biomass recovery at the level of primary producers, providing partial evidence for spatial insurance. The differential responses to dispersal may be linked to the much larger regional species pool of phytoplankton than of zooplankton. Our results suggest high recovery capacity of community biomass independent of dispersal. However, community composition and trophic structure remained altered due to the heatwave, implying longer-lasting changes in ecosystem functioning.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Spatharis, Dr Sofie
• Authors: Vad, C. F., Hanny‐Endrédi, A., Kratina, P., Abonyi, A., Mironova, E., Murray, D. S., Samchyshyna, L., Tsakalakis, I., Smeti, E., Spatharis, S., Tan, H., Preiler, C., Petrusek, A., Bengtsson, M. M., and Ptacnik, R.
• College/School: College of Medical Veterinary and Life Sciences > School of Biodiversity, One Health & Veterinary Medicine
• Journal Name: Global Change Biology
• Publisher: Wiley
• ISSN: 1354-1013
• ISSN (Online): 1365-2486
• Published Online: 22 March 2023
• Copyright Holders: Copyright © 2023 The Authors
• First Published: First published in Global Change Biology 29(11):3054-3071
• Publisher Policy: Reproduced under a Creative Commons License
• Data DOI: 10.5061/dryad.02v6wwq75