title: Assessment of the air-soil partitioning of polycyclic aromatic hydrocarbons in a paddy field using a modified fugacity sampler.
abstract: Rice, one of the most widely cultivated crops, has received great attention in contaminant uptake from soil and air, especially for the special approaches used for its cultivation. The dry-wet alternation method can influence the air-soil partitioning of semivolatile organic compounds (SVOCs) in the paddy ecosystem. Here, we modified a fugacity sampler to investigate the air-surface in situ partitioning of ubiquitous polycyclic aromatic hydrocarbons (PAHs) at different growth stages in a suburban paddy field in South China. The canopy of rice can form a closed space, which acts like a chamber that can force the air under the canopy to equilibrate with the field surface. When we compared the fugacities calculated using a fugacity model of the partition coefficients to the measured fugacities, we observed similar trends in the variation, but significantly different values between different growing stages, especially during the flooding stages. However, the measured and calculated fugacity fractions were comparable when uncertainties in our calculations were considered, with the exception of the high molecular weight (HMW) PAHs. The measured fugacity fractions suggested that the HMW PAHs were also closed to equilibrium between the paddy field and atmosphere. The modified fugacity sampler provided a novel way of accurately determining the in situ air-soil partitioning of SVOCs in a wet paddy field.
authors.affiliation: Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology , Dalian 116024, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Wang
authors.forename: Chunling
authors.initials: C
authors.lastname: Luo
authors.forename: Shaorui
authors.initials: S
authors.lastname: Wang
authors.forename: Junwen
authors.initials: J
authors.lastname: Liu
authors.forename: Suhong
authors.initials: S
authors.lastname: Pan
authors.forename: Jun
authors.initials: J
authors.lastname: Li
authors.forename: Lili
authors.initials: L
authors.lastname: Ming
authors.forename: Gan
authors.initials: G
authors.lastname: Zhang
authors.forename: Xiangdong
authors.initials: X
authors.lastname: Li
mesh_terms: D000388:Air / Q000032:analysis*; D000393:Air Pollutants / Q000737:chemistry*; D002681:China; D012275:Oryza / Q000502:physiology*; D011084:Polycyclic Aromatic Hydrocarbons / Q000737:chemistry*; D012987:Soil / Q000737:chemistry*; D012989:Soil Pollutants / Q000737:chemistry*
chemical_list: D000393:Air Pollutants; D011084:Polycyclic Aromatic Hydrocarbons; D012987:Soil; D012989:Soil Pollutants