Data from: Experimental evidence for neonicotinoid driven decline in aquatic emerging insects

There is an ongoing unprecedented loss in insects, both in terms of richness and biomass. The usage of pesticides, especially neonicotinoid insecticides, has been widely suggested to be a contributor to this decline. However, the risks of neonicotinoids to natural insect populations have remained largely unknown due to lack of field-realistic experiments. Here, we used an outdoor experiment to determine effects of field-realistic concentrations of the commonly applied neonicotinoid thiacloprid on the emergence of naturally assembled aquatic insect populations. Following application, all major orders of emerging aquatic insects (Coleoptera, Diptera, Ephemeroptera, Odonata, Trichoptera) declined strongly in both abundance and biomass. At the highest concentration (10 μg/L), emergence of most orders was nearly absent. Diversity of the most species-rich family, Chironomidae, decreased by 50% at more commonly observed concentrations (1 μg/L) and was generally reduced to a single species at the highest concentration. Our experimental findings thereby showcase a causal link of neonicotinoids and the ongoing insect decline. Given the urgency of the insect decline, our results highlight the need to reconsider the mass usage of neonicotinoids to preserve freshwater insects as well as the life and services depending on them.

当前昆虫正经历前所未有的种群衰退，无论物种丰富度还是生物量均大幅下降。农药的使用，尤其是新烟碱类杀虫剂（neonicotinoid insecticides），被广泛认为是此次衰退的重要诱因之一。但由于缺乏符合野外实际场景的实验，新烟碱类农药对自然昆虫种群的风险在很大程度上仍未明确。本研究通过室外实验，探究了常用新烟碱类药剂噻虫啉（thiacloprid）的野外实际浓度对自然聚集的水生昆虫种群羽化情况的影响。施药后，所有主要类群的羽化水生昆虫——鞘翅目（Coleoptera）、双翅目（Diptera）、蜉蝣目（Ephemeroptera）、蜻蛉目（Odonata）、毛翅目（Trichoptera）——的个体数量与生物量均显著下降。在最高浓度（10微克/升）处理组中，多数昆虫类群的羽化活动几乎完全消失。作为物种最丰富的类群，摇蚊科（Chironomidae）在常见野外浓度（1微克/升）处理下的多样性下降了50%，而在最高浓度组中其物种数仅余1种。本实验结果证实了新烟碱类农药与当前昆虫种群衰退之间存在因果关联。鉴于昆虫种群衰退的紧迫性，本研究结果呼吁重新审视新烟碱类农药的大规模使用，以保护淡水昆虫及其赖以生存的生命活动与生态系统服务功能。