Straw return in paddy field alters photodegradation of organic contaminants by changing the quantity rather than the quality of water-soluble soil organic matter

Wu，Dongming1; Li，Min2; Du，Ling2; Ren，Dong2,3; Wang，Junjian4

2022-05-15

10.1016/j.scitotenv.2022.153371

SCIENCE OF THE TOTAL ENVIRONMENT   影响因子和分区

0048-9697

1879-1026

Straw return, an important agricultural management practice, is worldwide adopted to enhance soil carbon sequestration and soil fertility. Although water-soluble soil organic matter (WSOM) in paddy field is known to affect the photodegradation of organic contaminants, how straw return regulates the photosensitization of WSOM by changing its properties remain unclear. Here, we determined the temporal variations in the content, chemical characteristics, and photosensitizing ability of WSOM after wheat straw return in a wheat-rice rotation system using optical spectroscopy and steady-state photodegradation tests. After straw return, the WSOM content first increased to a maximum and then gradually decreased to pre-return level at day 90. Nevertheless, the relative abundance of humic-like components in WSOM was not shifted by straw return, and protein-like component in WSOM just showed a slight decrease at day 45. All the WSOM samples inhibited sulfamethoxazole (SMX) photodegradation by light filtering, reactive species quenching and other mechanisms, while promoted diuron (DIU) degradation via reacting with •OH, O and excited triplet WSOM. The photodegradation of SMX and DIU was little affected by straw return changing WSOM composition and photochemical activity. However, straw return could decelerate SMX and DIU photodegradation by elevating WSOM content in a relatively short-term. This study emphasizes that straw return may reduce the photodegradation of organic contaminants by increasing WSOM concentration instead of altering WSOM chemical characteristics.

Dissolved organic matter Organic contaminants Paddy field Photodegradation Straw return

SCI ; EI

英语

其他

National Natural Science Foundation of China[41807379,42007135] ; Applied Basic Research Foundation of Science and Technology Department of Sichuan Province[2019YJ0340] ; Guangdong Natural Science Funds for Distinguished Young Scholar[2021B1515020082] ; Key Platform and Scientific Research Projects of Guangdong Provincial Education Department["2019KZDXM028","2020KCXTD006"] ; Central Public-interest Scientific Institution Basal Research Fund for Chinese Academy of Tropical Agricultural Sciences[1630042021013]

Environmental Sciences & Ecology

Environmental Sciences

WOS:000766801100001

ELSEVIER

20220511568060

Biogeochemistry ; Contamination ; Herbicides ; Soil testing ; Soils ; Water quality

Water Analysis:445.2 ; Geochemistry:481.2 ; Soils and Soil Mechanics:483.1 ; Biochemistry:801.2 ; Organic Compounds:804.1

ENVIRONMENT/ECOLOGY

2-s2.0-85123698579

Scopus

1.Institute of Environment and Plant Protection,Chinese Academy of Tropical Agricultural Sciences,Haikou,571101,China
2.College of Environmental Science and Engineering,China West Normal University,Nanchong,637009,China
3.Chemical Synthesis and Pollution Control Key Laboratory of Sichuan Province,China West Normal University,Nanchong,637009,China
4.State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution Control,School of Environmental Science and Engineering,Southern University of Science and Technology,Shenzhen,518055,China

Wu，Dongming,Li，Min,Du，Ling,et al. Straw return in paddy field alters photodegradation of organic contaminants by changing the quantity rather than the quality of water-soluble soil organic matter[J]. SCIENCE OF THE TOTAL ENVIRONMENT,2022,821.

Wu，Dongming,Li，Min,Du，Ling,Ren，Dong,&Wang，Junjian.(2022).Straw return in paddy field alters photodegradation of organic contaminants by changing the quantity rather than the quality of water-soluble soil organic matter.SCIENCE OF THE TOTAL ENVIRONMENT,821.

Wu，Dongming,et al."Straw return in paddy field alters photodegradation of organic contaminants by changing the quantity rather than the quality of water-soluble soil organic matter".SCIENCE OF THE TOTAL ENVIRONMENT 821(2022).