Advanced

Below-ground responses of silver birch trees exposed to elevated CO2 and O-3 levels during three growing seasons

Kasurinen, A; Keinanen, MM; Kaipainen, S; Nilsson, Lars Ola LU ; Vapaavuori, E; Kontro, MH and Holopainen, T (2005) In Global Change Biology 11(7). p.1167-1179
Abstract
Field-growing silver birch (Betula pendula Roth) clones (clone 4 and 80) were exposed to elevated CO2 and O-3 in open-top chambers for three consecutive growing seasons (1999-2001). At the beginning of the OTC experiment, all trees were 7 years old. We studied the single and interaction effects of CO2 and O-3 on silver birch below-ground carbon pools (i.e. effects on fine roots and mycorrhizas, soil microbial communities and sporocarp production) and also assessed whether there are any clonal differences in these below-ground CO2 and O-3 responses. The total mycorrhizal infection level of both clones was stimulated by elevated CO2 alone and elevated O-3 alone, but not when elevated CO2 was used in fumigation in combination with elevated... (More)
Field-growing silver birch (Betula pendula Roth) clones (clone 4 and 80) were exposed to elevated CO2 and O-3 in open-top chambers for three consecutive growing seasons (1999-2001). At the beginning of the OTC experiment, all trees were 7 years old. We studied the single and interaction effects of CO2 and O-3 on silver birch below-ground carbon pools (i.e. effects on fine roots and mycorrhizas, soil microbial communities and sporocarp production) and also assessed whether there are any clonal differences in these below-ground CO2 and O-3 responses. The total mycorrhizal infection level of both clones was stimulated by elevated CO2 alone and elevated O-3 alone, but not when elevated CO2 was used in fumigation in combination with elevated O-3. In both clones, elevated CO2 affected negatively light brown/orange mycorrhizas, while its effect on other mycorrhizal morphotypes was negligible. Elevated O-3, instead, clearly decreased the proportions of black and liver-brown mycorrhizas and increased that of light brown/orange mycorrhizas. Elevated O-3 had a tendency to decrease standing fine root mass and sporocarp production as well, both of these O-3 effects mainly manifesting in clone 4 trees. CO2 and O-3 treatment effects on soil microbial community composition (PLFA, 2- and 3-OH-FA profiles) were negligible, but quantitative PLFA data showed that in 2001 the PLFA fungi : bacteria-ratio of clone 80 trees was marginally increased because of elevated CO2 treatments. This study shows that O-3 effects were most clearly visible at the mycorrhizal root level and that some clonal differences in CO2 and O-3 responses were observable in the below-ground carbon pools. In conclusion, the present data suggests that CO2 effects were minor, whereas increasing tropospheric O-3 levels can be an important stress factor in northern birch forests, as they might alter mycorrhizal morphotype assemblages, mycorrhizal infection rates and sporocarp production. (Less)
Please use this url to cite or link to this publication:
author
organization
publishing date
type
Contribution to journal
publication status
published
subject
in
Global Change Biology
volume
11
issue
7
pages
1167 - 1179
publisher
Wiley-Blackwell
external identifiers
  • wos:000230336800015
  • scopus:27744506681
ISSN
1354-1013
DOI
10.1111/j.1365-2486.2005.00970.x
language
English
LU publication?
yes
id
f8e2066b-d21b-4ea9-9295-30592fca8bf4 (old id 146771)
date added to LUP
2007-06-29 11:16:44
date last changed
2017-09-10 03:42:56
@article{f8e2066b-d21b-4ea9-9295-30592fca8bf4,
  abstract     = {Field-growing silver birch (Betula pendula Roth) clones (clone 4 and 80) were exposed to elevated CO2 and O-3 in open-top chambers for three consecutive growing seasons (1999-2001). At the beginning of the OTC experiment, all trees were 7 years old. We studied the single and interaction effects of CO2 and O-3 on silver birch below-ground carbon pools (i.e. effects on fine roots and mycorrhizas, soil microbial communities and sporocarp production) and also assessed whether there are any clonal differences in these below-ground CO2 and O-3 responses. The total mycorrhizal infection level of both clones was stimulated by elevated CO2 alone and elevated O-3 alone, but not when elevated CO2 was used in fumigation in combination with elevated O-3. In both clones, elevated CO2 affected negatively light brown/orange mycorrhizas, while its effect on other mycorrhizal morphotypes was negligible. Elevated O-3, instead, clearly decreased the proportions of black and liver-brown mycorrhizas and increased that of light brown/orange mycorrhizas. Elevated O-3 had a tendency to decrease standing fine root mass and sporocarp production as well, both of these O-3 effects mainly manifesting in clone 4 trees. CO2 and O-3 treatment effects on soil microbial community composition (PLFA, 2- and 3-OH-FA profiles) were negligible, but quantitative PLFA data showed that in 2001 the PLFA fungi : bacteria-ratio of clone 80 trees was marginally increased because of elevated CO2 treatments. This study shows that O-3 effects were most clearly visible at the mycorrhizal root level and that some clonal differences in CO2 and O-3 responses were observable in the below-ground carbon pools. In conclusion, the present data suggests that CO2 effects were minor, whereas increasing tropospheric O-3 levels can be an important stress factor in northern birch forests, as they might alter mycorrhizal morphotype assemblages, mycorrhizal infection rates and sporocarp production.},
  author       = {Kasurinen, A and Keinanen, MM and Kaipainen, S and Nilsson, Lars Ola and Vapaavuori, E and Kontro, MH and Holopainen, T},
  issn         = {1354-1013},
  language     = {eng},
  number       = {7},
  pages        = {1167--1179},
  publisher    = {Wiley-Blackwell},
  series       = {Global Change Biology},
  title        = {Below-ground responses of silver birch trees exposed to elevated CO2 and O-3 levels during three growing seasons},
  url          = {http://dx.doi.org/10.1111/j.1365-2486.2005.00970.x},
  volume       = {11},
  year         = {2005},
}