Primary Succession Changes the Composition and Functioning of the Protist Community on Mine Tailings, Especially Phototrophic Protists

Yongbin Li; Pin Gao; Xiaoxu Sun; Baoqin Li; Lifang Guo; Rui Yang; Xianfa Su; Wenlong Gao; Zhimin Xu; Geng Yan; Qi Wang; Weimin Sun

doi:10.1021/acsenvironau.1c00066

Primary Succession Changes the Composition and Functioning of the Protist Community on Mine Tailings, Especially Phototrophic Protists

ACS Environ Au. 2022 Jun 29;2(5):396-408. doi: 10.1021/acsenvironau.1c00066. eCollection 2022 Sep 21.

Authors

Yongbin Li¹, Pin Gao¹, Xiaoxu Sun¹, Baoqin Li¹, Lifang Guo¹, Rui Yang¹, Xianfa Su², Wenlong Gao¹, Zhimin Xu³, Geng Yan¹, Qi Wang¹, Weimin Sun^{1

2}

Affiliations

¹ National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China.
² School of Environment, Key Laboratory of Yellow River and Huai River Water Environment and Pollution Control, Ministry of Education, Henan Normal University, Xinxiang 453007, P.R. China.
³ Engineering and Technology Research Center for Agricultural Land Pollution Prevention and Control of Guangdong Higher Education Institutes, College of Resources and Environment, Zhongkai University of Agriculture and Engineering, Guangzhou 510225, China.

Abstract

Primary succession in mine tailings is a prerequisite for tailing vegetation. Microorganisms, including bacteria, fungi, and protists, play an important role in this process in the driving force for improving the nutritional status. Compared to bacteria and fungi, protist populations have rarely been investigated regarding their role in mine tailings, especially for those inhabiting tailings associated with primary succession. Protists are the primary consumers of fungi and bacteria, and their predatory actions promote the release of nutrients immobilized in the microbial biomass, as well as the uptake and turnover of nutrients, affecting the functions of the wider ecosystems. In this study, three different types of mine tailings associated with three successional stages (original tailings, biological crusts, and Miscanthus sinensis grasslands) were selected to characterize the protistan community diversity, structure, and function during primary succession. Some members classified as consumers dominated the network of microbial communities in the tailings, especially in the original bare land tailings. The keystone phototrophs of Chlorophyceae and Trebouxiophyceae showed the highest relative abundance in the biological crusts and grassland rhizosphere, respectively. In addition, the co-occurrences between protist and bacterial taxa demonstrated that the proportion of protistan phototrophs gradually increased during primary succession. Further, the metagenomic analysis of protistan metabolic potential showed that abundances of many functional genes associated with photosynthesis increased during the primary succession of tailings. Overall, these results suggest that the primary succession of mine tailings drives the changes observed in the protistan community, and in turn, the protistan phototrophs facilitate the primary succession of tailings. This research offers an initial insight into the changes in biodiversity, structure, and function of the protistan community during ecological succession on tailings.