R. Miller1, David Loehlen2, Zhanna Yermakov2, Victoria Allison3, Susan Kirt2, Roser Matamala2, and Adam Langley4. (1) Argonne National Laboratory, Biosciences Div. D203-E161, 9700 S. Cass Ave.-Arg. Natl Lb, Argonne, IL 60439, (2) Environ. Res. Div. D203-E161, 9700 S. Cass Ave.-Arg. Natl Lb, Bldg 203, Argonne, IL 60439, (3) Landcare Research, Canterbury, 8152, New Zealand, (4) Smithsonian Environmental Research Center, Edgewater, MD 21037
Elevated CO2 and ozone were found to influence the growth
and allocation of extraradical ectomycorrhizal mycelia
(ERM) in Aspen
by using 30μm mesh bags. The study
took place at the FACTII FACE site near Rhinelander, WI. Mesh bags were collected at 296, 366 and 447
days after being buried to a depth of 10 cm.
We found that significant CO2 and O3 main effects were evident with elevated
CO2 demonstrating a 54 % increase in ERM, while elevated O3 showed a 40 %
decline. Fumigation with CO2 was found
to dampen the O3 effect where ERM production was decreased under the CO2 x O3
treatment by 8 % compared to 60 % for O3 by itself. Only a slight increase in ERM was evident
with elevated CO2. C-mineralization of
hyphae demonstrates a significant CO2 effect with both treatments mineralizing
mycelia at a faster rate than ambient or O3 grown mycelia. Nitrogen content of the mycelia was also
influenced by the treatments with ambient averaging 2.1 % while the fumigation
treatments demonstrated a reduced N content.
The implications of these fumigation effects will be discussed.