Modelling the accumulation of microplastics through food webs with the example Baiyangdian Lake, China.

Microplastic plastics (MPs) is an increasingly widely serious global environment problem, which severely threats aquatic organisms and even human beings. However, the potential change trend of MPs abundance over time in natural aquatic ecosystems and the cumulative effects through food webs are unclear. In this research, the model of accumulation effect of MPs through aquatic food webs was established in the example Baiyangdian Lake (China) using the contaminant tracer module Ecotracer in the Ecopath modelling software. The results indicated that the MPs spread and accumulate throughout the food-web fast, and finally to the high trophic level aquatic organisms, Snakehead. The abundance of MPs in aquatic environment and organisms varies periodically with rainfall. The abundance of MPs in snakehead, mandarin fish, common carp, crucian carp, chub, fingerling, grass carp, mollusc, microzoobenthos, zooplankton increased about 3.97, 2.87, 2.35, 1.8, 1.48, 1.8, 1.86, 1.98, 1.99, 3.49 times of the initial abundance of MPs in them, respectively. Since snakehead exists in the highest trophic level in Baiyangdian Lake ecosystem, the cumulative effect of MPs is the most serious through food web. Furthermore, the accumulation of MPs in different trophic levels has a time delay effect, and the higher the nutrient level is, the more obvious the delay effect is. The results also showed that Ecotracer is a good model to explore the enrichment effect of MPs in food web, the accumulation of MPs through food webs is serious, and the phenomenon should arouse serious attention.