Geographical patterns of denitrifying bacterial communities associated with different urban lakes

Haihan Zhang; Zhenfang Zhao; Shengnan Chen; Yue Wang; Ji Feng; Jingyu Jia; Pengliang Kang; Sulin Li

doi:10.1039/c8ra01295d

Geographical patterns of denitrifying bacterial communities associated with different urban lakes

RSC Adv. 2018 May 9;8(31):17079-17090. doi: 10.1039/c8ra01295d.

Authors

Haihan Zhang^{1

2

3}, Zhenfang Zhao^{1

2

3}, Shengnan Chen^{1

2

3}, Yue Wang^{1

2

3}, Ji Feng^{1

2

3}, Jingyu Jia^{1

2

3}, Pengliang Kang^{1

2

3}, Sulin Li^{1

2

3}

Affiliations

¹ Key Laboratory of Northwest Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology Xi'an 710055 P. R. China zhanghaihan@xauat.edu.cn +86-29-82202729 +86-29-82202854.
² Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology Xi'an 710055 P. R. China.
³ Institute of Environmental Microbial Technology, Xi'an University of Architecture and Technology Xi'an 710055 P. R. China.

Abstract

The geographical variation of denitrifying bacterial communities and water quality parameters in urban lakes distributed across nine provinces in China were determined. The Illumina sequencing data of the denitrifying encoding gene nirS was examined in the samples collected from nine localities (pairwise geographical distance: 200-2600 km). The results showed that fundamental differences in water quality were observed among different urban lakes. The highest nitrate (2.02 mg L^-1) and total nitrogen (3.82 mg L^-1) concentrations were observed in Pingzhuang (P < 0.01). The algal cell concentration ranged from 1.29 × 10⁸ to 3.0 × 10⁹ cell per L. The sequencing data generated a total of 421058 high quality nirS gene reads that resulted in 6369 OTUs (97% cutoff), with Proteobacteria and Firmicutes being the dominant taxa. A co-occurrence network analysis indicated that the top five genera identified as keystone taxa were Dechlorospirillum sp., Alicycliphilus sp., Dechloromonas sp., Pseudogulbenkiania sp., and Paracoccus sp. A redundancy analysis (RDA) further revealed that distinct denitrifying bacterial communities inhabited the different urban lakes, and influenced by urban lake water ammonia nitrogen, manganese and algal cell concentrations. A variance partitioning analysis (VPA) also showed that geographic location was more important than water quality factors in structuring the denitrifying bacterial communities. Together, these results provide new insight into understanding of denitrifying bacterial communities associated with geographically distributed urban lakes on a larger scale, and these results also expand our exploration of aquatic microbial ecology in freshwater bodies.