title: Phosphine in paddy fields and the effects of environmental factors.
abstract: Ambient levels of phosphine (PH3) in the air, phosphine emission fluxes from paddy fields and rice plants, and the distribution of matrix-bound phosphine (MBP) in paddy soils were investigated throughout the growing stages of rice. The relationships between MBP and environmental factors were analyzed to identify the principal factors determining the distribution of MBP. The phosphine ambient levels ranged from 2.368±0.6060 ng m(-3) to 24.83±6.529 ng m(-3) and averaged 14.25±4.547 ng m(-3). The highest phosphine emission flux was 22.54±3.897 ng (m(2)h)(-1), the lowest flux was 7.64±4.83 ng (m(2)h)(-1), and the average flux was 14.17±4.977 ng (m(2)h)(-1). Rice plants transport a significant portion of the phosphine emitted from the paddy fields. The highest contribution rate of rice plants to the phosphine emission fluxes reached 73.73% and the average contribution was 43.00%. The average MBP content of 111.6 ng kg(-1)fluctuated significantly in different stages of rice growth and initially increased then decreased with increasing depth. The peak MBP content in each growth stage occurred approximately 10 cm under the surface of paddy soils. Pearson correlation analyses and stepwise multiple regression analysis showed that soil temperature (Ts), acid phosphatase (ACP) and total phosphorus (TP) were the principal environmental factors, with correlative rankings of Ts>ACP>TP.
authors.affiliation: College of Environment and Energy, South China University of Technology, Guangzhou 510006, China; The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, Guangzhou 510006, China; The Key Laboratory of Environmental Protection and Eco-Remediation of Guangdong Regular Higher Education Institutions, Guangzhou 510006, China. Electronic address: niuweizuhe@gmail.com.
authors.forename: Xiaojun
authors.initials: X
authors.lastname: Niu
authors.forename: Aishu
authors.initials: A
authors.lastname: Wei
authors.forename: Yadong
authors.initials: Y
authors.lastname: Li
authors.forename: Lina
authors.initials: L
authors.lastname: Mi
authors.forename: Zhiquan
authors.initials: Z
authors.lastname: Yang
authors.forename: Xiaofei
authors.initials: X
authors.lastname: Song
mesh_terms: D018556:Crops, Agricultural / Q000737:chemistry*; D004784:Environmental Monitoring; D012275:Oryza / Q000737:chemistry*; D010720:Phosphines / Q000032:analysis*; D010758:Phosphorus / Q000032:analysis; D012987:Soil / Q000737:chemistry; D012989:Soil Pollutants / Q000032:analysis*
chemical_list: D010720:Phosphines; D012987:Soil; D012989:Soil Pollutants; D010758:Phosphorus; C044646:phosphine
keywords: Acid phosphatase; MBP; Paddy; Phosphine