In this study, the occurrence and distribution of microplastics in artificial reefs around the Ma’an Archipelago, a national marine ranching area in China, were investigated. The abundance of microplastics ranged from 0.2 ± 0.1 to 0.6 ± 0.2 items L −1 in surface water, 30.0 ± 0.0 to 80.0 ± 14.1 items kg −1 dry weight in the sediment, and 2.3 ± 1.5 to 7.3 ± 3.5 items individual −1 in fish. Most of the detected microplastics were fiber-shaped, blue or transparent, and smaller than 1 mm. Polyethylene, polypropylene, and poly(ethylene:propylene:diene) copolymer were the most abundant polymer types in the surface water samples, whereas cellophane was dominant in the sediment and fish. The appearance of microplastic pollution around the artificial reefs could be attributed mainly to the activities of the fisheries in the area, whereas the microplastic ingestion by fish was affected by the extent of microplastic contamination of the sediment. The results highlight the widespread presence of microplastics in the water, sediment, and biota of the artificial reefs around the Ma’an Archipelago, thereby improving understanding of the environmental risks posed by microplastics to marine artificial reef ecosystems and fisheries in general.
Y zeolite is presently used as an important active component in oil refining catalysts. The efficient synthesis of NaY zeolite still faces many huge challenges. Herein, a novel method for the rapid synthesis of nano-plate-like small crystal-sized NaY zeolite through an artificial-fish-reef-breeding negative crystal strategy is reported. It was discovered that cationic polyacrylamide (CPAM) could act as an artificial fish-reef to breed negative crystals, which promoted NaY zeolite nucleation and accelerated the crystallization of NaY zeolite. The crystallization time of NaY zeolite was shortened by 9 h. The relevant crystallization mechanism was investigated. Nano-plate-like (10–50 nm) small-sized (100–200 nm) NaY zeolite crystals with exceptional thermal stability and a large total volume (0.447 cm3 g−1) were synthesized. After steam treatment, the nano-plate-like small-sized USY-CPAM zeolites possessed reasonable acid sites distribution, endowing them with superior cracking activity for heavy reactant molecules.