Heatwaves, elevated temperature, and insecticide-induced effects at different trophic levels of a freshwater ecosystem
Hermann, Markus Schuijt, Lara Albini, Dania Amekor, Mawuli K Belgers, Dick Boerwinkel, Marie-Claire Evarita, Ann M Huang, Anna Jackson, Michelle C Peeters, Edwin THM
Hermann, Markus
Schuijt, Lara
Albini, Dania
Amekor, Mawuli K
Belgers, Dick
Boerwinkel, Marie-Claire
Evarita, Ann M
Huang, Anna
Jackson, Michelle C
Peeters, Edwin THM
Series / Report no.
Open Access
Type
Journal Article
Article
Article
Language
en
Date of publication
2025-04-08
Year of publication
Research Projects
Organizational Units
Journal Issue
Title
Heatwaves, elevated temperature, and insecticide-induced effects at different trophic levels of a freshwater ecosystem
Translated Title
Published in
Environ Res 2025; 277:121566
Abstract
Heatwaves and increasing average temperatures associated with climate change pose severe stress on nature, including freshwater ecosystems. As these thermal stressors do not act in isolation over temporal or spatial scales, interactions with other stressors, like pesticides, may lead to unpredictable combined effects. Empirical studies investigating multiple stressor effects across different trophic levels are scarce and often lack environmental realism. Here, we performed a multiple stressor experiment using outdoor freshwater mesocosms and realistic pond assemblages including microbes, phytoplankton, macrophytes, and invertebrates. The effects of the pesticide imidacloprid at three dosings (0, 1, 10 μg/L) were examined in combination with three temperature scenarios comprising natural ambient, elevated temperatures (+4 °C), and repeated heatwaves (+8 °C). Our results reveal fast imidacloprid dissipation for all temperature treatments with the lowest average dissipation half-lives (DT: 6 days) in the heatwave treatment. Imidacloprid induced a series of significant effects on the macroinvertebrate community at 10 μg/L across the temperature treatments. Significant declines in abundance appeared throughout the experiment for the most sensitive taxa Cloeon dipterum, Caenis sp., Chironomini, and Dero sp., whereas significant imidacloprid effects on Tanytarsini, Chironomus, and Gammarus pulex occurred only after each dosing. Only Zygoptera showed an imidacloprid-related increase in abundance, whereas significantly adverse time-cumulative effects on abundance occurred for Asellus aquaticus. The zooplankton community showed imidacloprid tolerance (10 μg/L) with increasing abundances of Chydorus sphaericus, Acroperus harpae, and Ascomorpha. Heatwaves induced significantly meliorating effects on Dero sp. and adverse effects on Caenis sp., Tanytarsini, G. pulex, and A. harpae. The macroinvertebrate community demonstrated faster post-exposure recovery dynamics in the highest imidacloprid treatment when previously exposed to heatwaves and elevated temperatures compared to ambient conditions. Overall, heatwaves amplified the effects of imidacloprid on the invertebrate community, manifesting in manifold effects that adversely impacted multiple trophic levels.