Bundschuh Mirco, Zubrod Jochen P, Wernicke Theo, Konschak Marco, Werner Leon, Brühl Carsten A, Baudy Patrick, Schulz Ralf
iES Landau Institute for Environmental Sciences University of Koblenz-Landau Landau Germany.
Department of Aquatic Sciences and Assessment Swedish University of Agricultural Sciences Uppsala Sweden.
Ecol Evol. 2021 Mar 21;11(9):4353-4365. doi: 10.1002/ece3.7332. eCollection 2021 May.
Biodiversity is under pressure worldwide, with amphibians being particularly threatened. Stressors related to human activity, such as chemicals, are contributing to this decline. It remains, however, unclear whether chemicals exhibiting a fungicidal activity could indirectly affect tadpoles that depend on microbially conditioned leaf litter as food source. The indirect effect of fungicides (sum concentration of a fungicide mixture composed of azoxystrobin, carbendazim, cyprodinil, quinoxyfen, and tebuconazole: 100 µg/L) on tadpoles was assessed relative to leaf litter colonized by microbes in absence of fungicides (control) and a worst-case scenario, that is leached leaf litter without microbial colonization. The quality of leaf litter as food for tadpoles of the European common frog () was characterized through neutral lipid fatty acid profiles and microbial sum parameters and verified by sublethal responses in tadpoles (i.e., feeding rate, feces production, growth, and fatty acid composition). Fungicides changed the nutritious quality of leaf litter likely through alterations in leaves' neutral lipid fatty acid profiles (i.e., changes in some physiologically important highly unsaturated fatty acids reached more than 200%) in combination with a potential adsorption onto leaves during conditioning. These changes were reflected by differences in the development of tadpoles ultimately resulting in an earlier start of metamorphosis. Our data provide a first indication that fungicides potentially affect tadpole development indirectly through bottom-up effects. This pathway is so far not addressed in fungicide environmental risk assessment and merits further attention.
全球生物多样性正面临压力，两栖动物尤其受到威胁。与人类活动相关的压力源，如化学物质，正在导致这种减少。然而，具有杀真菌活性的化学物质是否会间接影响依赖微生物处理过的落叶作为食物来源的蝌蚪，仍不清楚。相对于在无杀菌剂情况下（对照）被微生物定殖的落叶以及最坏情况即无微生物定殖的淋溶落叶，评估了杀菌剂（由嘧菌酯、多菌灵、嘧菌环胺、喹氧灵和戊唑醇组成的杀菌剂混合物的总浓度：100 μg/L）对蝌蚪的间接影响。通过中性脂质脂肪酸谱和微生物总和参数表征了欧洲普通青蛙（）蝌蚪的落叶食物质量，并通过蝌蚪的亚致死反应（即摄食率、粪便产生、生长和脂肪酸组成）进行了验证。杀菌剂可能通过改变叶片的中性脂质脂肪酸谱（即一些生理上重要的高度不饱和脂肪酸的变化达到200%以上）以及在处理过程中可能吸附到叶片上，从而改变了落叶的营养质量。这些变化反映在蝌蚪发育的差异上，最终导致变态提前开始。我们的数据首次表明，杀菌剂可能通过自下而上的效应间接影响蝌蚪发育。到目前为止，这条途径在杀菌剂环境风险评估中尚未涉及，值得进一步关注。
