Xinjiang Key Laboratory of Environmental Pollution and Bioremediation, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, 830011, China; University of Chinese Academy of Sciences, Beijing, 100049, China.
Xinjiang Key Laboratory of Environmental Pollution and Bioremediation, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, 830011, China.
Environ Pollut. 2020 Oct;265(Pt A):114641. doi: 10.1016/j.envpol.2020.114641. Epub 2020 Apr 21.
Plastic debris provides a stable substrate and novel ecological niche for microorganisms in the aquatic environment, which was referred to as "Plastisphere". Little is known about distribution patterns and responses of ecological function and structure of microbial communities in the plastisphere along rivers which usually have antibiotics pollution gradient. In this study, the differences in the community structure between the plastisphere and the planktonic bacteria, and their spatial variation of the community structure and function along a river with increased antibiotics pollution gradient was investigated at the watershed scale. The diversity of bacteria colonized on most plastic debris was higher than in surrounding water. Plastic debris could accumulate a higher abundance of some potential pathogens than surrounding water even at high antibiotics concentrations. The source tracking results showed that downstream plastisphere inherited much higher proportions of bacterial taxa from upstream than planktonic bacteria. About 92.3-99.7% of bacteria communities in downstream water were not from upstream but from the input of downstream human activities. On the contrary, high proportions of bacterial taxa in downstream plastisphere were closely connected to upstream. The plastisphere possesses higher ecological functional diversity than the planktonic bacteria. Seventy nine functional groups across plastisphere were predicted using functional annotation of prokaryotic taxa and only 65 functional groups were found in the planktonic bacteria. Plastisphere also acts as hotspot for biogeochemical cycling of nutrients such as N and S. Intensive human activities of urban and downstream agriculture and aquaculture had great effects on microbial community structure and functional groups of the Urumqi River. Pastisphere communities are much more resistant to human disturbance than planktonic bacteria. Compared to surrounding water, plastisphere increased inheritance from upstream microbial structure and function and also increased survival and propagation of pathogens in the downstream water with high concentrations of antibiotics.
塑料碎片为水生环境中的微生物提供了稳定的基质和新的生态位，这被称为“塑料表层”。然而，关于河流中塑料表层微生物群落的生态功能和结构的分布模式及其响应，我们知之甚少，因为这些河流通常存在抗生素污染梯度。在本研究中，我们在流域尺度上研究了抗生素污染梯度增加的河流中，塑料表层和浮游细菌之间的群落结构差异，以及它们的空间变异。与周围水体相比，附着在大多数塑料碎片上的细菌多样性更高。即使在高抗生素浓度下，塑料碎片也可以积累更高丰度的一些潜在病原体。来源追踪结果表明，下游塑料表层比浮游细菌从上游继承了更高比例的细菌分类群。下游水中约 92.3%-99.7%的细菌群落不是来自上游，而是来自下游人类活动的输入。相反，下游塑料表层中高比例的细菌分类群与上游密切相关。塑料表层比浮游细菌具有更高的生态功能多样性。通过对原核分类群的功能注释，预测了塑料表层的 79 个功能群，而在浮游细菌中仅发现了 65 个功能群。塑料表层也是氮和硫等营养物质生物地球化学循环的热点。城市和下游农业和水产养殖业的人类活动对乌鲁木齐河的微生物群落结构和功能群产生了巨大影响。与浮游细菌相比，过去表层群落对人类干扰的抵抗力更强。与周围水体相比，塑料表层增加了对上游微生物结构和功能的遗传，同时也增加了抗生素浓度高的下游水中病原体的存活和繁殖。
