Contrasting responses to long-term climate change of carbon flows to benthic consumers in two different sized lakes in the Baltic area

Abstract

The study of lake sediments and archived biological remains is a promising approach to better understand the impacts of climate change on aquatic ecosystems. Small lakes have been shown to be strongly sensitive to past climate change, but similar information is lacking for large lakes. By identifying responses to climate change of carbon flows through benthic food web in two different sized lakes, we aimed to understand how lake morphometry can mediate the effects of climate change. We reconstructed the dynamics of phytoplankton community composition and carbon resources sustaining chironomid biomass during the Holocene from the combined analysis of sedimentary pigment quantification and carbon stable isotopic composition of subfossil chironomid head capsules (delta C-13(Hc)) in a large lake in the Baltic area (Estonia). Our results showed that chironomid biomass in the large lake was mainly sustained by phytoplankton, with no significant relationship between delta C-13(Hc) values and temperature fluctuations. We suggest that lake morphometry (including distance of the sampling zone to the shoreline, and lake volume for primary producers) mediates the effects of climate change, making large lakes less sensitive to climate change. Complementary studies are needed to better understand differences in organic matter dynamics in different sized lakes and to characterize the response of the aquatic carbon cycle to past climate change. 2018 Elsevier Ltd. All rights reserved.

Keywords

Climate change; Benthic food web; Large lake; Carbon stable isotope; Subfossil chironomid

Published in

Quaternary Science Reviews
2018, Volume: 187, pages: 168-176
Publisher: PERGAMON-ELSEVIER SCIENCE LTD

SLU Authors

• Belle, Simon

  • Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences
    
  • Estonian University of Life Sciences

Sustainable Development Goals

SDG13 Climate action


UKÄ Subject classification

Oceanography, Hydrology, Water Resources


Publication identifier

DOI: https://doi.org/10.1016/j.quascirev.2018.03.027

Permanent link to this page (URI)

https://res.slu.se/id/publ/95107