School of Science, Tibet University, Lhasa 850000, China; State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China.
State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China.
Sci Total Environ. 2022 Jul 1;828:154399. doi: 10.1016/j.scitotenv.2022.154399. Epub 2022 Mar 8.
Microplastics have been reported in a wide range of aquatic habitats. The wetlands are considered to be important roles in microplastic migration in water bodies. Nevertheless, knowledge about the occurrence and fate of microplastics in urban natural wetland is still limited for us to better understand how they become a sink of microplastics. In this study, the distribution and characteristics of microplastics in surface water, surface sediments, and sediment cores of the Lalu Wetland watershed, China's highest urban wetland, were investigated in August 2020 and January 2021. The abundances of microplastics in the surface water were 0.06-3.05 MPs/L. Microplastic abundance in the surface sediment and sediment core was 0.01-1.10 MPs/g and 0-16.23 MPs/g, respectively. The abundance of microplastics in the water was significantly lower in the wetland than that in the channel in the watershed. Comparing the wetland inlet and outlet water, the microplastic interception rates were 53% in January and 95% in August. The characteristics and seasonal variation of microplastics in the Lalu Wetland implied that urban natural wetlands were good at intercepting microplastics, and vegetation growth might play an important role on the interception of microplastics by the wetland. The increasing of microplastics from bottom to top in the sediment cores of Lalu Wetland also indicated that the ecological risks of microplastics accumulation in sediments of urban natural wetland required further attention.
微塑料已在广泛的水生栖息地中被报道。湿地被认为是水体中微塑料迁移的重要角色。然而，我们对城市自然湿地中微塑料的存在和归宿的了解仍然有限，无法更好地理解它们如何成为微塑料的汇。在这项研究中，于 2020 年 8 月和 2021 年 1 月调查了中国最高城市湿地——拉鲁湿地流域地表水、表层沉积物和沉积物芯中微塑料的分布和特征。地表水中微塑料的丰度为 0.06-3.05 MPs/L。表层沉积物和沉积物芯中的微塑料丰度分别为 0.01-1.10 MPs/g 和 0-16.23 MPs/g。流域湿地中的微塑料丰度明显低于河道。比较湿地进出口水，微塑料截留率在 1 月为 53%，8 月为 95%。拉鲁湿地微塑料的特征和季节性变化表明，城市自然湿地善于拦截微塑料，植被生长可能对湿地拦截微塑料起着重要作用。拉鲁湿地沉积物芯中从底部到顶部微塑料的增加也表明，城市自然湿地沉积物中微塑料积累的生态风险需要进一步关注。
