Sulfur isotopic signatures in rainwater and moss Haplocladium microphyllum indicating atmospheric sulfur sources in Nanchang City (SE China)

Sulfur source identification previously reported has been based on sulfur isotopic ratios in either rainwater or mosses. The δ34S values of rainwater sulfate and the epilithic moss Haplocladium microphyllum in Nanchang region (China) were determined for comparisons and used to delineate atmospheric sulfur sources. At the urban and rural sites, similar mean δ34S values were observed between rainwater sulfate (+ 1.6‰ and − 0.2‰, respectively) and epilithic mosses (+ 1.7‰ and + 0.6‰, respectively), suggesting that mosses acquire δ34S values similar to those found for rainwater sulfate. This has further demonstrated that moss δ34S signatures hold valuable source-specific information as rainwater δ34S values do. The δ34S values of both rainwater sulfate and epilithic mosses indicated that atmospheric sulfur in Nanchang region was mainly associated with coal combustion. The lower δ34S values at the rural site can be explained by higher contribution of local coals (lower δ34S values relative to those of north Chinese coals) and biogenic sulfur.

Research Highlights
► Mosses acquire δ34S values similar to those found for rainwater sulfate.
► Moss δ34S signatures hold valuable source-specific information.
► Atmospheric S in Nanchang region was mainly associated with coal combustion.