Taxonomic Composition Change after Environmental Levels Addition of Polyethylene Microplastic (PE-MPs) to Mediterranean Sediment: Case Study of Bizerte Lagoon Nematodes Communities

The current study examined the meiobenthic populations’ response, to the influence of the most detected micro-sized microplastics polyethylene (PE-MPs) in aquatic system. Three concentrations [PE1 (0.1 μg/g Dry weight (DW)), PE2 (1 μg/g DW), and PE3 (10 μg/g DW)] were progressively applied and the experiment was run for a month in the existence or lack of meiofauna. Our results showed that PE-MPs declined meiofauna taxa abundance, as well as, marine nematodes univariate indices were significantly affected. A change in taxonomic structure has been recorded leading to an increase in the mean difference between nematode genera with increasing doses of PE-MPs. Differences in nematodes sensitivities to this polymer occurred. Cyatholaimus, Paracomesoma, Oncholaimus, Oncholaimellus, Ascolaimus, Synonchiella were present in all conditions and categorized as tolerant to PE-MPs. Nematodes detected only in control compartments, including Microlaimus, Desmodora, Paramonohystera, and Metoncholaimus were considered the most sensitive compared to Terschellingia, Calomicrolaimus, Paramonohystera, Daptonema, Metalinhomoeus, Odontophora.

Keywords: Pe-Mps Enriched Sediment, Meiobenthic Taxa, Nematodes Genus, Population Response, Taxonomic Structure.