Electronic Supplementary Material s21

ELECTRONIC SUPPLEMENTARY MATERIAL

Bacterial community composition at anodes of microbial fuel cells for paddy soils: the effect of soil properties

Ning Wang, Zheng Chen, Hong-Bo Li, Jian-Qiang Su, Feng Zhao, and Yong-Guan Zhu*

*Correspondence author

Ning Wang, Zheng Chen, Yong–Guan Zhu

State Key Laboratory of Urban and Regional Ecology, Research Center for Eco– Environmental Sciences, Chinese Academy of Sciences, Beijing, China. Email: [email protected]

Ning Wang

University of Chinese Academy of Sciences, Beijing, China.

Zheng Chen

Department of Environmental Science, Xi’an Jiaotong-Liverpool University, Suzhou, China.

Hong-Bo Li

State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, China.

Jian-Qiang Su, Feng Zhao, Yong-Guan Zhu

Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, China. Table S1. Sampling information and basic properties of the used five types of paddy soils. Pad Sampling site Soil type Soil parent Soil Water pH TC (%) dy material texture Content (%) soil LZ Yingli town, Leizhou Humid-thermo Basalt Silty 36.5 ± 2.72a 5.40 ± 0.01b 1.27 ± 0.02 peninsula, Guangdong ferralitic clay province JX Jinxin village, Xuxin Yellow River-sea Silty 36. 1 ± 3.54a 5.95 ± 0.06a 1.69 ± 0.02 town, Nanhu district, mottled soil two-phase loam Jiaxing city, Zhejiang alluvia province YT Red Soil Station, Red soil Quaternary Silty 38.9 ± 3.91a 5.24 ± 0.04c 1.23 ± 0.03 Chinese Academy red clay soil Institute, Yingtan city, Jiangxi province

CA Gushi village, Red soil Yuanjiang Silty 28.4 ± 2.75b 5.94 ± 0.03a 2.61 ± 0.04 Chehuwan town, River loam Taoyuan country, alluviun Changde city, Hunan province CR Baodongyu village, Red soil Quaternary Silty 26.7 ± 1.26b 5.17 ± 0.01d 2.25 ± 0.02 Zhangjiang town, red clay loam Taoyuan country, Changde city, Hunan province Table S2. pH and EC of the overlying water, total carbon and nitrogen contents in soil near anode, and anode potential at day 58 for the used 5 paddy soils with MFC treatment. –1 Paddy soils pH EC(s cm ) TC (%) TN (%) Eah (mV) LZ 6.40 ± 0.15b 642 ± 16b 1.13 ± 0.05d 0.15 ± 0.01d –145 ± 7.2b

JX 8.00 ± 0.10a 423 ± 98c 1.65 ± 0.04c 0.22 ± 0.01c –127 ±14.3b – YT 7.80 ± 0.30a 423 ± 99c 1.10 ± 0.12d 0.15 ± 0.02d 138 ± 10.3b CA 7.89 ± 0.34a 806 ± 59a 2.37 ± 0.03a 0.29 ± 0.01a –254 ± 8.2a

CR 7.76 ± 0.23a 438 ± 59c 2.11 ± 0.11b 0.26 ± 0.01b –231 ± 6.3a Data were given as mean ± standard deviation (n = 3) in MFC soil. Different upper letters indicated significant (p < 0.05) differences in soil characteristics among paddy soils MFC.

Abbreviations refer to: TC, total carbon; TN, total nitrogen; EC, electrical conductivity; Eah, anode potential; JX, Jiaxing soil; LZ, Leizhou soil; YT, Yingtan soil; CA, Changde Alluvium soil; CR, Changde Red soil. Figure Captions

Fig. S1 Temporal change of current density in the used 5 types of paddy soils with MFC treatments during 58 days.

Fig. S2 Genus distribution of bacterial community composition at MFC anodes for paddy soils. Each treatment had 3 MFC replicates. Other, include the low abundance bacteria

(<0.2%) and the taxonomically-unassigned sequences at genus level.

Fig. S3 Principle component analysis (PCA) of bacterial community composition at anodes for paddy soils without and with MFC treatments. Each treatment had 3 replicates. Fig. S1 Fig. S2 Fig. S3