Biogeochemistry of Sulfur and Mercury in Soil Warming and Atmospheric CO2 Enrichment Experiments in Northern Peatlands
EMSL Project ID
48400
Abstract
We propose to utilize EMSL’s ultra high resolution mass spectrometry capabilities to determine the molecular composition of organic S-containing compounds in pore water dissolved organic matter (DOM) along three different peatland types in Northern Minnesota, The S1 bog, S3 fen and bog lake fen. Peatland watersheds are important sites of methyl mercury (Hg) production, which is a well-known neurotoxin that accumulates in aquatic organisms. It has been found that the speciation and microbial processing of sulfur (S) has a significant impact on mercury speciation and transport in northern peatlands. In this study, we therefore investigate, through the use of mass spectrometry, how organic S speciation affects net MeHg production rates in porewaters across northern peatlands with different physical, chemical, vegetation, and hydrological characteristics. A mechanistic understanding of S and Hg speciation in peatlands and pore waters is critical for predicting the response of peatlands to climate change. The results of this study will be used to better conceptualize, as well as parameterize models that project how climate change will affect the accumulation, cycling, and export of S and toxic methylmercury from peatlands. In addition, detailed S speciation will improve our mechanistic understanding of S diagenesis and burial processes in peatland watersheds for the purposes of paleoenvironmental reconstruction and petroleum formation studies.
Project Details
Start Date
2014-04-26
End Date
2014-09-30
Status
Closed
Released Data Link
Team
Principal Investigator