The dynamics of microplastic pollution in coastal zones, in the context of climate change, is a crucial global environmental issue. This study investigated and analyzed changes in microplastic abundance, composition, and diversity in beach sediments in Xiamen City before and after Typhoon Haikui. The results showed that the abundance of microplastics on the beaches in Xiamen City before Typhoon Haikui was (251.5 ± 27.9) n/kg, which significantly decreased to (127.0 ± 18.8) n/kg post-typhoon. Before and after the typhoon, the composition of microplastics on the beaches exhibited distinct variations. In particular, the abundance of smaller particles (<500 μm) significantly decreased, while the proportion of fibrous particles increased. Moreover, the typhoon event led to a general decrease in the Shannon-Wiener diversity index, while the Pielou’s evenness index increased. Based on the results of this study and previous research, it is concluded that heavy rainfall is the driving factor behind the changes in microplastic abundance and composition on Xiamen’s beaches caused by Typhoon Haikui. The impact of typhoons on the dynamics of microplastic pollution in coastal zones results from the coupling of multiple physical processes, influenced by a complex combination of factors, such as dynamic conditions, sediment physical and chemical factors, and topography. In the future, it will be necessary to conduct long-term monitoring of hydrological and meteorological data, and to carry out more in-depth, systematic, and comprehensive research on the underlying mechanisms.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |