PARENT SESSION
Poster Session 32: Biogeochemistry
Thursday, August 11, 5:00 PM - 6:30 PM, Exhibit Hall 220 A-E, Level 2, Palais des congrès de Montréal
Methyl bromide emissions from fungi in different ecosystems.
Varner, Ruth1, Blanchard, Robert1, Dailey, Gail1, 1 University of New Hampshire, Durham, NH
ABSTRACT- Methyl chloride (CH3Cl) and methyl bromide (CH3Br) are methyl halide gases that contribute ozone-destroying radicals to the stratosphere. In an effort to better understand the global budget of methyl halides and their impact on the atmosphere, we need to identify their natural sources and sinks in addition to the known anthropogenic sources of these compounds. Soils and wetlands in southern New Hampshire, USA, have been identified as both sources and sinks of methyl chloride and methyl bromide. We are investigating the role of fungi in the production of these methyl halides. Our research sites include four ecosystems: an agricultural field, a temperate forest, a fresh water wetland, and coastal salt marshes. Measurements of headspace gas extracted from flasks containing fungal cultures demonstrate that a variety of fungi collected from temperate forests and wetlands in New Hampshire emit methyl bromide. Preliminary results of flux data for 24 samples range from 0.77 to 95.2 pmols CH3Br per gram of fungal biomass per day. Our goal is to extrapolate the flux data to a global estimate of methyl halide emissions.
Key words: methyl halides, methyl bromide, fungi, ozone