摘要

微塑料在许多海洋生境中的迅速传播引起了对海洋生物群和生态系统后果的关注。微塑料对海洋无脊椎动物的许多不利影响是摄入的后果。因此，确定促进微塑料吸收的机制对于评估对海洋生物和食物网可能产生的影响至关重要。腹足动物产生粘液用于运动。腹足动物踏板粘液自然保留以前悬浮的微生物，如细菌，微藻和海藻孢子。保留的生物被腹足动物消耗，这些腹足动物在脚蹬粘液上觅食。在这里，我们调查了腹足动物踏板粘液的潜力，以保留悬浮的微粒弹性颗粒，并使它们可以被污染的粘液上的长春花吸收。在实验室实验中，长春花（Littorina littorea）和Littorina obtusata的粘液有效地保留了微塑料。微塑料的保留在来自不同大小的同种的粘液之间变化，但在来自任一物种的粘液之间不变。粘液痕迹中的微塑料密度随着实验颗粒浓度的增加而增加，但与孵育时间无关。粘液老化，特别是干燥，影响了微塑料的保留。长春花在沾染污染的粘液时摄入微塑料。我们的研究结果揭示了微塑料的生物成因与海洋底栖食草动物向海洋食物网的营养转移之间的功能联系。

The rapid dissemination of microplastics in many habitats of the oceans has raised concerns about the consequences for marine biota and ecosystems. Many adverse effects of microplastics on marine invertebrates are consequences of ingestion. Accordingly, the identification of mechanisms that facilitate the uptake of microplastics is essential for the evaluation of possible implications for marine organisms and food webs. Gastropods produce mucus for locomotion. Gastropod pedal mucus naturally retains formerly suspended micro-organisms, such as bacteria, microalgae, and seaweed spores. The retained organisms are consumed by gastropods that forage on pedal mucus. Here, we investigated the potential of gastropod pedal mucus to retain suspended microplastic particles and make them available for ingestion by periwinkles that forage on the contaminated mucus. In laboratory experiments, mucus of the periwinkles Littorina littorea and Littorina obtusata efficiently retained microplastics. Retention of microplastics varied between mucus from conspecifics of different size but not between mucus from either species. The density of microplastics in mucus trails increased concomitantly with the experimental particle concentration but was independent of incubation time. Aging of mucus and, particularly, desiccation affected the retention of microplastics. Periwinkles ingested microplastics when foraging on the contaminated mucus. Our results reveal a functional link between biogenic accumulation of microplastics and their trophic transfer by marine benthic herbivores into marine food webs.

https://www.ncbi.nlm.nih.gov/pubmed/30616059