In the context of S and N pollutant remediation, this study aimed to develop a methodology to test the ability of wetland plants to reduce atmospheric pollution by S and N. A methodology using 34S and 15N-labeled Sinapsis alba compost and five species (trap plants) used to fix volatile compounds was developed. 18.66% of 34S and 40.63% of 15N produced by Sinapsis alba compost, equivalent to 67 mg of S and 1611 mg of N, were recovered in trap plants, a negligible proportion of the labeling was found in the culture substrate. 34S and 15N atom% excess were two to ten times higher in leaves than in roots. Agrostis stolonifera, Symphytum officinale, and Lythrum salicaria were more efficient to use atmospheric inorganic sources of S and N than Mentha aquatica and Carex riparia. A low concentration of sulfate in the leaf laminas, a high specific leaf area, and a low leaf dry mass content could represent trait patterns that explain higher abilities to fix pollutants. This study confirms that plants can be used to remediate inorganic atmospheric pollution and highlights the importance of plant screening for this environmental function.Novelty statementThe removal efficiency of botanical biofiltration is well-documented for Volatile Organic pollutants, but little is known concerning Volatile Inorganic pollutants, such as SO2 and NH3 which can also constitute plant nutrients.We developed a methodology based on the use of 34S and 15N-labeled mustard compost to study the ability of wetland plant species to fix volatile N and S pollutants. This methodology was effective as 19% of 34S and 41% of 15N lost by mustard compost were recovered in trap plants. Among the species used as "trap plants" Agrostis stolonifera, Symphytum officinale, and Lythrum salicaria appeared more efficient to use atmospheric inorganic sources of S and N than Mentha aquatica and Carex riparia.
Keywords: Atmospheric pollution; nitrogen; phytoremediation; sulfur; volatilization.