Discrepant responses of the electron transfer capacity of soil humic substances to irrigations with wastewaters from different sources

Wenbing Tan; Yuan Zhang; Beidou Xi; Xiaosong He; Rutai Gao; Caihong Huang; Hui Zhang; Dan Li; Xinyu Zhao; Meng Li; Li Li; Jie Jiang; Guoan Wang

doi:10.1016/j.scitotenv.2017.08.060

Discrepant responses of the electron transfer capacity of soil humic substances to irrigations with wastewaters from different sources

Sci Total Environ. 2018 Jan 1:610-611:333-341. doi: 10.1016/j.scitotenv.2017.08.060. Epub 2017 Aug 11.

Authors

Wenbing Tan¹, Yuan Zhang², Beidou Xi³, Xiaosong He¹, Rutai Gao¹, Caihong Huang¹, Hui Zhang⁴, Dan Li⁴, Xinyu Zhao⁴, Meng Li⁴, Li Li⁵, Jie Jiang⁶, Guoan Wang⁷

Affiliations

¹ State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
² Hebei Provincial Academy of Environmental Sciences, Shijiazhuang 050037, China.
³ State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing 100012, China. Electronic address: xibeidou@yeah.net.
⁴ State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
⁵ College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China.
⁶ College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China.
⁷ College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China. Electronic address: gawang@cau.edu.cn.

PMID: 28806550
DOI: 10.1016/j.scitotenv.2017.08.060

Abstract

An increasing area of agricultural land is irrigated with wastewater worldwide due to the scarcity of fresh water resources. Whether wastewater irrigations can affect the electron transfer capacity (ETC) of natural organic matter in soils is unclear. In this study, we assess the responses of the electron-accepting capacity (EAC) and electron-donating capacity (EDC) of soil humic substances (HS) to irrigations with wastewaters from different sources. We show that the EAC of soil HS increases and the EDC of soil HS decreases after irrigation with domestic wastewater. Conversely, the EAC of soil HS decreases and the EDC of soil HS increases after irrigation with industrial wastewater. The EAC and EDC of soil HS exert no changes after irrigation with pharmaceutical wastewater. Irrigations with wastewaters from different sources can cause the distinct directions of changes in the activities of lignin peroxidase and laccase by altering the content of labile organic carbon, heavy metals or antibiotics in soils, thereby changing the chemical structures and finally the ETC of HS along different directions. These results can provide insights into the role of HS in environmentally relevant processes in agricultural soils under the context of wastewater irrigations.

Keywords: Electron accepting capacity; Electron donating capacity; Soil enzyme activity; Soil factors; Soil humic substances; Wastewater irrigation.